Stus-List Re: [EXTERNAL] Re: Balsa core history - problems and fixes

[CHARLES SCHEAFFER via CnC-List]

Hey Steve,
Found a guy who is replacing damaged core in his hull, but it's a huricane 
damaged catamaran.  YouTube channel, "Parley Revival"

Episode 94 and 95, 96 show some good techniques.  You can fast forward through 
the goofy parts.  His videos are meant more to have fun, be funny, and 
entertain, than to be instructional.  Enjoy:

https://www.youtube.com/watch?v=EpgjUZoIzvc=322s

https://www.youtube.com/watch?v=2D7g57ptKAI=170s



Chuck S


> On 09/17/2021 4:34 PM Steve Thomas via CnC-List  
> wrote:
> 
> 
> All,
> Much has been written about the problem of wet balsa when and if it 
> happens and I have seen many methods better and worse for deck repairs. What 
> I have not seen are examples of how people have gone about repairing wet 
> cored areas of the hull. Any pointers other than "forget about it" would be 
> appreciated.
> 
> Steve Thomas
> 
> 
> > > 
> > -- Original Message --
> > From: cnc-list@cnc-list.com
> > To: cnc-list@cnc-list.com
> > Cc: joe.della.ba...@ssa.gov; strig...@eastlink.ca
> > Sent: Friday, September 17, 2021 1:32 PM
> > Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history
> > 
> > 
> > Yes that old foam is crap. The new Coosa 
> > https://coosacomposites.com/the-coosa-advantage/ and equivalents do not 
> > soak up water and are put together under tons of pressure.
> > 
> > 
> > From: Della Barba, Joe via CnC-List 
> > Sent: September-17-21 11:21 AM
> > To: Stus-List 
> > Cc: Della Barba, Joe 
> > Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history
> > 
> > 
> > Typo
> > 
> > Water migrates slowly through end-grain balsa but really tears foam 
> > up
> > 
> > ---
> > 
> > Snip snip snip
> > 
> > 
> > 
> > Great info and research; so, how did balsa go from "wonder" 
> > material to; "bad stuff don't touch..."?
> > 
> > 
> > -
> > 
> > 
> > > 
> Thanks to all of the subscribers that contributed to the list to help 
> with the costs involved. If you want to show your support to the list - use 
> PayPal to send contribution -- https://www.paypal.me/stumurray Thanks - Stu
> 
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: [EXTERNAL] Re: Balsa core history - problems and fixes

[CHARLES SCHEAFFER via CnC-List]

Hi Steve,

I saw a detailed hull repair done on a C designed Northeast 39 a few years 
back.

A hull repair is done the same way as a deck.  Cutting below the waterline, 
there are less fittings to work around, but the repair is upside down so vacuum 
bagging would really improve the result, the look and the strength of the job 
as it would pull any air trapped inside.

First step is to use a light hammer to tap the hull and locate the wet core and 
mark where to cut. 

I'll try and find those pictures for you.

Chuck



> On 09/17/2021 4:34 PM Steve Thomas via CnC-List  
> wrote:
> 
> 
> All,
> Much has been written about the problem of wet balsa when and if it 
> happens and I have seen many methods better and worse for deck repairs. What 
> I have not seen are examples of how people have gone about repairing wet 
> cored areas of the hull. Any pointers other than "forget about it" would be 
> appreciated.
> 
> Steve Thomas
> 
> 
> > > 
> > -- Original Message --
> > From: cnc-list@cnc-list.com
> > To: cnc-list@cnc-list.com
> > Cc: joe.della.ba...@ssa.gov; strig...@eastlink.ca
> > Sent: Friday, September 17, 2021 1:32 PM
> > Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history
> > 
> > 
> > Yes that old foam is crap. The new Coosa 
> > https://coosacomposites.com/the-coosa-advantage/ and equivalents do not 
> > soak up water and are put together under tons of pressure.
> > 
> > 
> > From: Della Barba, Joe via CnC-List 
> > Sent: September-17-21 11:21 AM
> > To: Stus-List 
> > Cc: Della Barba, Joe 
> > Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history
> > 
> > 
> > Typo
> > 
> > Water migrates slowly through end-grain balsa but really tears foam 
> > up
> > 
> > ---
> > 
> > Snip snip snip
> > 
> > 
> > 
> > Great info and research; so, how did balsa go from "wonder" 
> > material to; "bad stuff don't touch..."?
> > 
> > 
> > -
> > 
> > 
> > > 
> Thanks to all of the subscribers that contributed to the list to help 
> with the costs involved. If you want to show your support to the list - use 
> PayPal to send contribution -- https://www.paypal.me/stumurray Thanks - Stu
> 
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: [EXTERNAL] Re: Balsa core history - problems and fixes

[dwight veinot via CnC-List]

I cut the outer fibreglass skin off with a rotary grinder. Nice straight
cuts and under the handrails after removing them.  I found the bad spots by
tapping with a hammer. Get a dull thud on tapping probably a wet rotten
spot. Dig out all the rotten stuff let dry and fill in with new half inch
thick end grain balsa matt. Use thickened polyester resin to apply and fill
like putty. Reinstall the fibreglass skin or just make a new one with
polyester resin and glass matt. Fill to surface with lightweight auto body
polyester filler and sand with a long sander. Paint with International
Brightside. Reinstall deck fittings. Good to go.

On Fri, Sep 17, 2021 at 5:34 PM Steve Thomas via CnC-List <
cnc-list@cnc-list.com> wrote:

> All,
> Much has been written about the problem of wet balsa when and if it
> happens and I have seen many methods better and worse for deck repairs.
> What I have not seen are examples of how people have gone about repairing
> wet cored areas of the hull. Any pointers other than "forget about it"
> would be appreciated.
>
> Steve Thomas
>
>
>
>
> -- Original Message --
> From: cnc-list@cnc-list.com
> To: cnc-list@cnc-list.com
> Cc: joe.della.ba...@ssa.gov; strig...@eastlink.ca
> Sent: Friday, September 17, 2021 1:32 PM
> Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history
>
> Yes that old foam is crap. The new Coosa
> https://coosacomposites.com/the-coosa-advantage/ and equivalents do not
> soak up water and are put together under tons of pressure.
>
> *From:* Della Barba, Joe via CnC-List 
> *Sent:* September-17-21 11:21 AM
> *To:* Stus-List 
> *Cc:* Della Barba, Joe 
> *Subject:* Stus-List Re: [EXTERNAL] Re: Balsa core history
>
> Typo
>
> Water migrates slowly through end-grain balsa but really tears foam up
>
> ---
> Snip snip snip
>
> 
>
> Great info and research; so, how did balsa go from "wonder" material to;
> "bad stuff don't touch..."?
> --
>
>
>
> Thanks to all of the subscribers that contributed to the list to help with
> the costs involved.  If you want to show your support to the list - use
> PayPal to send contribution --   https://www.paypal.me/stumurray  Thanks
> - Stu

-- 
Sent from Gmail Mobile
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List 1980 40 Cheetah needs TLC

[Tom Buscaglia via CnC-List]

I senior member of our Yacht club has pretty much 
abandoned his 1980 C 40.  He is very motivated 
to sell her but not willing to do much to get her 
sold.  She is not listed anywhere yet...


Cheetah was raced for years and has a decent 
complement of both racing and cruising 
sails.  The westbrook diesel was disassembled to 
clean some salt crystals out of the exit area 
from the exchanger and not reassembled.  So, she 
has not been run in 2-3 years along with 
everything else that goes with letting a boat sit 
for that long.  But she is a C and he may be 
willing to sell her to the right buyer for cheap!


If you are interested his name is Pete Clarke and 
he can be reached at pgr...@comcast.net.


Tom B

.¤º°`°º¤,¸¸,¤º°`°º¤¤º°`°º¤,¸¸,¤º°`°º¤.
Tom & Lynn Buscaglia
SV Alera
C 37+/40
Vashon Island WA
(206) 463-9200
www.sv-alera.com


Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: [EXTERNAL] Re: Balsa core history - problems and fixes

[Bill Coleman via CnC-List]

Matt can co-lead that discussion with Rob!

 

 

Bill Coleman

Entrada, Erie, PA

 

 

 

From: Steve Thomas via CnC-List [mailto:cnc-list@cnc-list.com] 
Sent: Friday, September 17, 2021 4:35 PM
To: cnc-list@cnc-list.com
Cc: Steve Thomas
Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history - problems and fixes

 

All,

Much has been written about the problem of wet balsa when and if it happens and 
I have seen many methods better and worse for deck repairs. What I have not 
seen are examples of how people have gone about repairing wet cored areas of 
the hull. Any pointers other than "forget about it" would be appreciated. 

Steve Thomas

 



-- Original Message --
From: cnc-list@cnc-list.com
To: cnc-list@cnc-list.com
Cc: joe.della.ba...@ssa.gov; strig...@eastlink.ca
Sent: Friday, September 17, 2021 1:32 PM
Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history

Yes that old foam is crap. The new Coosa 
https://coosacomposites.com/the-coosa-advantage/ and equivalents do not soak up 
water and are put together under tons of pressure.

From: Della Barba, Joe via CnC-List  
Sent: September-17-21 11:21 AM
To: Stus-List 
Cc: Della Barba, Joe 
Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history

Typo

Water migrates slowly through end-grain balsa but really tears foam up

--- 

Snip snip snip



Great info and research; so, how did balsa go from "wonder" material to; "bad 
stuff don't touch..."? 


  _  


 

 

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: [EXTERNAL] Re: Balsa core history - problems and fixes

[Steve Thomas via CnC-List]

All,
Much has been written about the problem of wet balsa when and if it 
happens and I have seen many methods better and worse for deck repairs. 
What I have not seen are examples of how people have gone about 
repairing wet cored areas of the hull. Any pointers other than "forget 
about it" would be appreciated.


Steve Thomas




   -- Original Message --
   From: cnc-list@cnc-list.com
   To: cnc-list@cnc-list.com
Cc: joe.della.ba...@ssa.gov; strig...@eastlink.ca
   Sent: Friday, September 17, 2021 1:32 PM
   Subject: Stus-List Re: [EXTERNAL]   Re: Balsa core history


Yes that old foam is crap.  The new Coosa 
https://coosacomposites.com/the-coosa-advantage/ 
  and equivalents do 
not soak up water and are put together under tons of pressure.



From: Della Barba, Joe via CnC-List 
Sent: September-17-21 11:21 AM
To: Stus-List 
Cc: Della Barba, Joe 
Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history


Typo
Water migrates slowly through end-grain balsa but really tears foam up
---
Snip snip snip



Great info and research; so, how did balsa go from "wonder" material to; 
"bad stuff don't touch..."?





Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Cancelled again

[Chuck Gilchrest via CnC-List]

I’ll volunteer to lead the first one.  Who wants to talk about rope?
Chuck

Sent from my iPhone

> On Sep 17, 2021, at 4:07 PM, Bill Coleman via CnC-List 
>  wrote:
> 
> 
> Sounds like a great idea, would probably put a little structure in the 
> discussion, and keep that part of it from meandering.
> You know Chuck, when you come up with a great idea, you also get a job!  . .  
> .
>  
> Bill Coleman
> Entrada, Erie, PA
>  
>  
>  
> From: Novabraid via CnC-List [mailto:cnc-list@cnc-list.com] 
> Sent: Friday, September 17, 2021 3:09 PM
> To: 'Stus-List'
> Cc: csgilchr...@comcast.net
> Subject: Stus-List Re: Cancelled again
>  
> Hey Stu,
> Just a thought: having the virtual rendezvous is a great idea and its always 
> good to see who shows up for any number of random discussions about our 
> boats, but perhaps we’d get more interest if the meet up was a bit more 
> focused, like when John Kelly Cuthbertson was able to talk about his dad’s 
> archives on C items.  We’ve had some lively chats in the email exchange 
> recently about A-4 engines and the choices available for charging systems and 
> electrical storage. Perhaps in each of the rendezvous, we could spend a bit 
> of time on a particular topic first and then open up the floor for other 
> discussions, maybe even inviting an outside source (Balmar, Beta Marine, an 
> AGL battery guy, etc) to be a guest “expert” on the focal subject.
> Given the wealth of knowledge that our owners have accumulated, putting a 
> monthly schedule of topics, perhaps seasonal in nature, might yield a bit 
> more participation.  And folks like Rob Mazza, John Kelly Cuthbertson, Rob 
> Ball, and others could also be scheduled in to field questions or lead 
> discussions.
> While this all may be a bit much from a planning standpoint, it wouldn’t be 
> difficult to start a list of topics that seem to be hot buttons for 
> discussion and take it from there…
> Suggestions for topics are welcome…
> Cheers,
> Chuck Gilchrest
> S/V Half Magic
> 1983 Landfall 35
> Padanaram, MA
>  
>  
> From: Stu via CnC-List  
> Sent: Thursday, September 16, 2021 12:09 PM
> To: C Email List 
> Cc: Stu 
> Subject: Stus-List Cancelled again
>  
> Since there appears to be little interest in tonite’s virtual zoom 
> rendezvous, I have cancelled it.
>  
> Maybe we will have more interest once the sailing season has slowed down.
>  
> Stay safe ‘n’ healthy.
>  
> Stu
> Thanks to all of the subscribers that contributed to the list to help with 
> the costs involved.  If you want to show your support to the list - use 
> PayPal to send contribution --   https://www.paypal.me/stumurray  Thanks - Stu
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Cancelled again

[Bill Coleman via CnC-List]

Sounds like a great idea, would probably put a little structure in the 
discussion, and keep that part of it from meandering.

You know Chuck, when you come up with a great idea, you also get a job!  . .  .

 

Bill Coleman

Entrada, Erie, PA

 

 

 

From: Novabraid via CnC-List [mailto:cnc-list@cnc-list.com] 
Sent: Friday, September 17, 2021 3:09 PM
To: 'Stus-List'
Cc: csgilchr...@comcast.net
Subject: Stus-List Re: Cancelled again

 

Hey Stu,

Just a thought: having the virtual rendezvous is a great idea and its always 
good to see who shows up for any number of random discussions about our boats, 
but perhaps we’d get more interest if the meet up was a bit more focused, like 
when John Kelly Cuthbertson was able to talk about his dad’s archives on C 
items.  We’ve had some lively chats in the email exchange recently about A-4 
engines and the choices available for charging systems and electrical storage. 
Perhaps in each of the rendezvous, we could spend a bit of time on a particular 
topic first and then open up the floor for other discussions, maybe even 
inviting an outside source (Balmar, Beta Marine, an AGL battery guy, etc) to be 
a guest “expert” on the focal subject.

Given the wealth of knowledge that our owners have accumulated, putting a 
monthly schedule of topics, perhaps seasonal in nature, might yield a bit more 
participation.  And folks like Rob Mazza, John Kelly Cuthbertson, Rob Ball, and 
others could also be scheduled in to field questions or lead discussions.

While this all may be a bit much from a planning standpoint, it wouldn’t be 
difficult to start a list of topics that seem to be hot buttons for discussion 
and take it from there…

Suggestions for topics are welcome… 

Cheers,

Chuck Gilchrest

S/V Half Magic

1983 Landfall 35

Padanaram, MA

 

 

From: Stu via CnC-List  
Sent: Thursday, September 16, 2021 12:09 PM
To: C Email List 
Cc: Stu 
Subject: Stus-List Cancelled again

 

Since there appears to be little interest in tonite’s virtual zoom rendezvous, 
I have cancelled it.

 

Maybe we will have more interest once the sailing season has slowed down.

 

Stay safe ‘n’ healthy.

 

Stu

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Cancelled again

[Novabraid via CnC-List]

Hey Stu,

Just a thought: having the virtual rendezvous is a great idea and its always 
good to see who shows up for any number of random discussions about our boats, 
but perhaps we’d get more interest if the meet up was a bit more focused, like 
when John Kelly Cuthbertson was able to talk about his dad’s archives on C 
items.  We’ve had some lively chats in the email exchange recently about A-4 
engines and the choices available for charging systems and electrical storage. 
Perhaps in each of the rendezvous, we could spend a bit of time on a particular 
topic first and then open up the floor for other discussions, maybe even 
inviting an outside source (Balmar, Beta Marine, an AGL battery guy, etc) to be 
a guest “expert” on the focal subject.

Given the wealth of knowledge that our owners have accumulated, putting a 
monthly schedule of topics, perhaps seasonal in nature, might yield a bit more 
participation.  And folks like Rob Mazza, John Kelly Cuthbertson, Rob Ball, and 
others could also be scheduled in to field questions or lead discussions.

While this all may be a bit much from a planning standpoint, it wouldn’t be 
difficult to start a list of topics that seem to be hot buttons for discussion 
and take it from there…

Suggestions for topics are welcome… 

Cheers,

Chuck Gilchrest

S/V Half Magic

1983 Landfall 35

Padanaram, MA

 

 

From: Stu via CnC-List  
Sent: Thursday, September 16, 2021 12:09 PM
To: C Email List 
Cc: Stu 
Subject: Stus-List Cancelled again

 

Since there appears to be little interest in tonite’s virtual zoom rendezvous, 
I have cancelled it.

 

Maybe we will have more interest once the sailing season has slowed down.

 

Stay safe ‘n’ healthy.

 

Stu

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: [EXTERNAL] Re: Balsa core history

[Rod Stright via CnC-List]

Yes that old foam is crap.  The new Coosa 
https://coosacomposites.com/the-coosa-advantage/ and equivalents do not soak up 
water and are put together under tons of pressure.

 

From: Della Barba, Joe via CnC-List  
Sent: September-17-21 11:21 AM
To: Stus-List 
Cc: Della Barba, Joe 
Subject: Stus-List Re: [EXTERNAL] Re: Balsa core history

 

Typo

Water migrates slowly through end-grain balsa but really tears foam up

 

From: Della Barba, Joe via CnC-List mailto:cnc-list@cnc-list.com> > 
Sent: Friday, September 17, 2021 10:18 AM
To: Stus-List mailto:cnc-list@cnc-list.com> >
Cc: Della Barba, Joe mailto:joe.della.ba...@ssa.gov> >
Subject: [EXTERNAL] Stus-List Re: Balsa core history

 

Time: I doubt anyone really thought through what balsa core would be like when 
it was 50-60-70 or more years old. A lot of things can go wrong with a lot of 
materials when past the half-century mark and headed towards 100.*

Bad Builders:  Some builders, mostly NOT C, were or are infamous for doing 
things wrong and having issues with relatively new boats.

Bad Owners: One unsealed thru-hull can eventually do a lot of damage.

 

* Our club uses Boston Whalers and we go through them. They eventually get 
saturated and weak, we send them to the dumpster, and get another one. Boston 
Whaler is a top builder and builds good boats, but decades of having the crap 
beat out of them eventually does them in, especially if any hull penetrations 
are not fixed ASAP. My Whaler is 51 years old and is still dry, it has never 
been a club boat and thus not beat like a rented mule by teenaged instructors. 
Note that the foam core in Whalers is MUCH WORSE than balsa once it gets wet. 
Water migrated through end-grain balsa, but it really tear up foam. I once went 
to put a thru-hull in a foam-core Krogen 42 and I got more than 50 gallons out 
of the core draining from the hole! That boat was essentially beyond repair, so 
it essentially got restricted to sheltered waters from then on.

 

Joe

Coquina

 

 

 

From: Richard Bush via CnC-List mailto:cnc-list@cnc-list.com> > 
Sent: Friday, September 17, 2021 9:18 AM
To: cnc-list@cnc-list.com  
Cc: cscheaf...@comcast.net  ; Richard Bush 
mailto:bushma...@aol.com> >
Subject: [EXTERNAL] Stus-List Re: Balsa core history

 

Great info and research; so, how did balsa go from "wonder" material to;  "bad 
stuff don't touch..."? 

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[John Irvin via CnC-List]

Really interesting and thorough explanation. Thank you!

Sent from my iPhone

On Sep 17, 2021, at 1:07 PM, CHARLES SCHEAFFER via CnC-List 
 wrote:


Thanks Rob for your detailed response.  I would love to learn more on the topic 
if you can provide links to any of the testing or procedures described for 
installing Baltek Balsa, I'd be most grateful.

My boatyard fiberglass guy works weekends fixing Sea Rays.  Mostly problems 
with brand new boats.

I'd also love to hear stories regarding your time at Hunter.  Different market 
than C but their designs were so inovative with their step up transom w 
storage lockers and aft head and aft cabin interiors and interior liner that 
formed a wiring chase.  Construction in Forida must have presented a different 
challenge than building in Canada.

Thanks,
Chuck Scheaffer, Resolute, 1989 C 34R, Annapolis
On 09/17/2021 12:09 PM Robert Mazza via CnC-List  wrote:


Interesting conversation, and thank you for asking for my input. Apologies for 
a late reply though, I've been up to my eyebrows, on behalf of the Marine 
Museum, in organizing the upcoming Canadian Sailing Hall of Fame Inductions on 
October 3rd in Kingston.

I started my career in the marine industry designing with C in the late '60s, 
and finished it in sales and marketing with Baltek in New Jersey from 2003 to 
2011. I thought it was appropriate to wrap up my career with Baltek, since 
balsa core was such an integral part of my design work with C It felt like 
closing a circle. However,the Baltek offices at the time being only 45 minutes 
from Manhattan was also a consideration.  What has been discussed to date is 
essentially accurate.  The Kohn family did escape from France in the early days 
of the 2nd WW and established business in New York City. Jacque Kohn spent time 
among their balsa plantations in Ecuador increasing the production of balsa 
wood, which at the time was considered a "strategic material" for the war 
effort, specifically for use in Navy carley floats and liferafts, and as 
mentioned previously for the Mosquito fighter/bomber, the wooden wonder. 
However, it was planks of flat-grain balsa that were used as a coring material 
in the fuselage between laminated birch skins, not end-grain. The fuselage was 
laid up over male molds in two halves then joined together after the electrical 
and hydraulics had been run down each side of the fuselage interior. Most of 
this work was done by women.

After the war, of course, demand for basa plummeted, resulting in a search for 
new markets other than model airplanes and fishing floats. One large market 
that developed was for insulation in LNG tankers, but that too died out with 
the development of new shipping methods. The story of Everet Pearson and the 
invention of end-grain balsa through Alex Lippay  is essentially true, but 
others were also experimenting with end-grain balsa as a core, specifically in 
the aircraft industry. Adding a scrim to blocks of end-grain balsa allowed the 
material to be applied in 2'x4' sheets and allowed the sheet to contour to the 
shape of the deck initially and then hulls. The advantage of end-grain over 
flat-grain as a core material, of course, is the exceptional increase in both 
compression strength and shear strength. End-grain balsa is essentially a 
honeycomb. The use of end-grain balsa between two load bearing skins created an 
engineered panel not unlike a three dimensional I-beam. It greatly increased 
stiffness and reduced weight compared to a single skin glass panel of the same 
strength. Initially it was used extensively in decks only. The first use in a 
hull laminate was with the building of Red Jacket in 1965 (see latest issue of 
Good Old Boat). It was Alex Lippay who guided Cuthbertson & Cassian and Erich 
Bruckmann in the building of Red Jacket. Bruckmann, of course, had never built 
a fiberglass boat in his life, let alone the most advanced composite laminate 
todate! Back in 2003 when I told George Cuthbertson that I was joining Baltek 
he asked me if Alex Lippay was still there. Alex, of course, had passed away 
many years ago, but was still  immortalized at Baltek in the designation for 
the precoating on balsa which was known as AL-600. Jacque and Margot Kohn, then 
in their '80s, were also still there, but had recently sold the company to 
Alcan, and were phasing out of the operations. Both Jacque and Margot, too, 
have since passed away. Working at Baltek was an amazing experience and I still 
maintain close friendships with the people who were there, most having worked 
their whole careers with the company. It was literally a family run business. 
The Alcan acquisition, and subsequent later acquisitions, of course, changed 
that, and the company suffered because of management by people who often did 
not understand the lumber business.

With the success of Red Jacket, C Yachts was created in 1969, and all three 
builders (Bruckmann, Hinterhoeller, and Morch) embraced balsa core 

Stus-List Re: Balsa core history

[CHARLES SCHEAFFER via CnC-List]

Thanks Rob for your detailed response.  I would love to learn more on the topic 
if you can provide links to any of the testing or procedures described for 
installing Baltek Balsa, I'd be most grateful.

My boatyard fiberglass guy works weekends fixing Sea Rays.  Mostly problems 
with brand new boats.

I'd also love to hear stories regarding your time at Hunter.  Different market 
than C but their designs were so inovative with their step up transom w 
storage lockers and aft head and aft cabin interiors and interior liner that 
formed a wiring chase.  Construction in Forida must have presented a different 
challenge than building in Canada.

Thanks,
Chuck Scheaffer, Resolute, 1989 C 34R, Annapolis

> On 09/17/2021 12:09 PM Robert Mazza via CnC-List  
> wrote:
> 
> 
> Interesting conversation, and thank you for asking for my input. 
> Apologies for a late reply though, I've been up to my eyebrows, on behalf of 
> the Marine Museum, in organizing the upcoming Canadian Sailing Hall of Fame 
> Inductions on October 3rd in Kingston. 
> 
> I started my career in the marine industry designing with C in the late 
> '60s, and finished it in sales and marketing with Baltek in New Jersey from 
> 2003 to 2011. I thought it was appropriate to wrap up my career with Baltek, 
> since balsa core was such an integral part of my design work with C It 
> felt like closing a circle. However,the Baltek offices at the time being only 
> 45 minutes from Manhattan was also a consideration.  What has been discussed 
> to date is essentially accurate.  The Kohn family did escape from France in 
> the early days of the 2nd WW and established business in New York City. 
> Jacque Kohn spent time among their balsa plantations in Ecuador increasing 
> the production of balsa wood, which at the time was considered a "strategic 
> material" for the war effort, specifically for use in Navy carley floats and 
> liferafts, and as mentioned previously for the Mosquito fighter/bomber, the 
> wooden wonder. However, it was planks of flat-grain balsa that were used as a 
> coring
  material in the fuselage between laminated birch skins, not end-grain. The 
fuselage was laid up over male molds in two halves then joined together after 
the electrical and hydraulics had been run down each side of the fuselage 
interior. Most of this work was done by women. 
> 
> After the war, of course, demand for basa plummeted, resulting in a 
> search for new markets other than model airplanes and fishing floats. One 
> large market that developed was for insulation in LNG tankers, but that too 
> died out with the development of new shipping methods. The story of Everet 
> Pearson and the invention of end-grain balsa through Alex Lippay  is 
> essentially true, but others were also experimenting with end-grain balsa as 
> a core, specifically in the aircraft industry. Adding a scrim to blocks of 
> end-grain balsa allowed the material to be applied in 2'x4' sheets and 
> allowed the sheet to contour to the shape of the deck initially and then 
> hulls. The advantage of end-grain over flat-grain as a core material, of 
> course, is the exceptional increase in both compression strength and shear 
> strength. End-grain balsa is essentially a honeycomb. The use of end-grain 
> balsa between two load bearing skins created an engineered panel not unlike a 
> three dimensional I-beam. It grea
 tly increased stiffness and reduced weight compared to a single skin glass 
panel of the same strength. Initially it was used extensively in decks only. 
The first use in a hull laminate was with the building of Red Jacket in 1965 
(see latest issue of Good Old Boat). It was Alex Lippay who guided Cuthbertson 
& Cassian and Erich Bruckmann in the building of Red Jacket. Bruckmann, of 
course, had never built a fiberglass boat in his life, let alone the most 
advanced composite laminate todate! Back in 2003 when I told George Cuthbertson 
that I was joining Baltek he asked me if Alex Lippay was still there. Alex, of 
course, had passed away many years ago, but was still  immortalized at Baltek 
in the designation for the precoating on balsa which was known as AL-600. 
Jacque and Margot Kohn, then in their '80s, were also still there, but had 
recently sold the company to Alcan, and were phasing out of the operations. 
Both Jacque and Margot, too, have since passed away. Working at Baltek was an 
 amazing experience and I still maintain close friendships with the people who 
were there, most having worked their whole careers with the company. It was 
literally a family run business. The Alcan acquisition, and subsequent later 
acquisitions, of course, changed that, and the company suffered because of 
management by people who often did not understand the lumber business. 
> 
> With the success of Red Jacket, C Yachts was created in 1969, and all 
> three builders (Bruckmann, Hinterhoeller, and Morch) embraced balsa core 
> construction for hulls and decks. 

Stus-List Re: Balsa core history

[Robert Mazza via CnC-List]

Interesting conversation, and thank you for asking for my input. Apologies
for a late reply though, I've been up to my eyebrows, on behalf of the
Marine Museum, in organizing the upcoming Canadian Sailing Hall of Fame
Inductions on October 3rd in Kingston.

I started my career in the marine industry designing with C in the late
'60s, and finished it in sales and marketing with Baltek in New Jersey from
2003 to 2011. I thought it was appropriate to wrap up my career with
Baltek, since balsa core was such an integral part of my design work with
C It felt like closing a circle. However,the Baltek offices at the time
being only 45 minutes from Manhattan was also a consideration.  What has
been discussed to date is essentially accurate.  The Kohn family did
escape from France in the early days of the 2nd WW and established business
in New York City. Jacque Kohn spent time among their balsa plantations in
Ecuador increasing the production of balsa wood, which at the time was
considered a "strategic material" for the war effort, specifically for use
in Navy carley floats and liferafts, and as mentioned previously for the
Mosquito fighter/bomber, the wooden wonder. However, it was planks of
flat-grain balsa that were used as a coring material in the fuselage
between laminated birch skins, not end-grain. The fuselage was laid up over
male molds in two halves then joined together after the electrical and
hydraulics had been run down each side of the fuselage interior. Most of
this work was done by women.

After the war, of course, demand for basa plummeted, resulting in a search
for new markets other than model airplanes and fishing floats. One large
market that developed was for insulation in LNG tankers, but that too died
out with the development of new shipping methods. The story of Everet
Pearson and the invention of end-grain balsa through Alex Lippay  is
essentially true, but others were also experimenting with end-grain balsa
as a core, specifically in the aircraft industry. Adding a scrim to
blocks of end-grain balsa allowed the material to be applied in 2'x4'
sheets and allowed the sheet to contour to the shape of the deck initially
and then hulls. The advantage of end-grain over flat-grain as a core
material, of course, is the exceptional increase in both compression
strength and shear strength. End-grain balsa is essentially a honeycomb.
The use of end-grain balsa between two load bearing skins created an
engineered panel not unlike a three dimensional I-beam. It greatly
increased stiffness and reduced weight compared to a single skin glass
panel of the same strength. Initially it was used extensively in decks
only. The first use in a hull laminate was with the building of *Red Jacket*
in 1965 (see latest issue of Good Old Boat). It was Alex Lippay who guided
Cuthbertson & Cassian and Erich Bruckmann in the building of *Red Jacket*.
Bruckmann, of course, had never built a fiberglass boat in his life, let
alone the most advanced composite laminate todate! Back in 2003 when I told
George Cuthbertson that I was joining Baltek he asked me if Alex Lippay was
still there. Alex, of course, had passed away many years ago, but was
still  immortalized at Baltek in the designation for the precoating on
balsa which was known as AL-600. Jacque and Margot Kohn, then in their
'80s, were also still there, but had recently sold the company to Alcan,
and were phasing out of the operations. Both Jacque and Margot, too, have
since passed away. Working at Baltek was an amazing experience and I still
maintain close friendships with the people who were there, most having
worked their whole careers with the company. It was literally a family run
business. The Alcan acquisition, and subsequent later acquisitions, of
course, changed that, and the company suffered because of management by
people who often did not understand the lumber business.

With the success of* Red Jacket*, C Yachts was created in 1969, and all
three builders (Bruckmann, Hinterhoeller, and Morch) embraced balsa core
construction for hulls and decks. Most of my time at Baltek was teaching
builders, even as late as the 2000s how to install core correctly - fillet
all edges, prewet before installing, fill all kerfs, isolate the core from
all openings, vacuum bag or infuse if possible, etc,. etc. If installed
properly, balsa core will last forever.* Red Jacket's* hull is a testament
to that. Her deck, not so much! People will willy-nilly drill holes in
decks, but not hulls.*  Red Jacket*, of course, has recently been donated
to the Marine Museum of the Great Lakes at Kingston. Her arrival has been
delayed due to the complications of Covid.

Reference has been made to Dan Spurr's excellent book Heart of Glass. Dan
is a long time friend and my editor at both Professional Boatbuilder
magazine and Good Old Boat magazine. Anyone interested in the history of
fiberglass boat building needs to have a copy of that book in their
library. It even has a chapter on Canadian 

Stus-List Re: Balsa core history

[Rod Stright via CnC-List]

Coosa is an excellent product for a core.  Expensive  it worth every penny

Sent from my iPhone

> On Sep 17, 2021, at 11:55 AM, Neil Andersen via CnC-List 
>  wrote:
> 
> 
> Some of the new coring material (divinicell??) is supposed to address the 
> balsa/foam issues.
> 
> Anyone with specific knowledge??
> 
> Neil Andersen
> Rock Hall, MD 21661
> 484-354-8800
> From: CHARLES SCHEAFFER via CnC-List 
> Sent: Friday, September 17, 2021 10:39:29 AM
> To: Stus-List 
> Cc: CHARLES SCHEAFFER 
> Subject: Stus-List Re: Balsa core history
>  
> That's a great story about Pearson starting the end grain orientation.  I 
> wonder if that's 100% true.  I'll bet several others would have thought of 
> that as well.  Anyone who works with wood knows the compression strength is 
> best when wood grain is oriented that way.  Honeycomb cores are end grain 
> oriented for the same reason. 
> 
> I read an article I can't seem to find again, that compared balsa to foam as 
> coring and they determined the balsa was better; stronger bond because the 
> end grain wicks up resin, lower cost, better for the environment too, as it's 
> a renewable source.  Coosa board has better water resistance but it's so much 
> more expensive; it comes in sheets that add to shipping costs.  ContourKore 
> Balsa is a series of cut squares, attached to a scrim that can be rolled so 
> it packs into a smaller package and ships for less.  I used balsa to replace 
> wet core on my boat.  Some of the wet balsa still had a very strong hold on 
> the fiberglass, and I had to use a chisel to pry it loose and an angle 
> grinder to smooth the remnants off.  Pretty amazing stuff.
> 
> Chuck S
> 
> 
>> On 09/16/2021 6:21 PM Lisle Kingery, PhD via CnC-List 
>>  wrote:
>> 
>> 
>> FWIW, this prompted me to take a look at the book "Heart of Glass: 
>> Fiberglass boats and the men who made them": and some info on Balsa is on 
>> p122,
>> 
>> "Balsa Core. The Baltek Corporation was the exclusive supplier to powerboat 
>> builders of balsa planks for stiffening hull sides and bottoms. When balsa 
>> was originally supplied in lengths with the grain running longitudinally, 
>> Pearson had problems with water migrating away from the point of entry at 
>> the deck hardware fasteners, causing delamination. Everett Perason recalls 
>> that "We were using pieces 3 feet long by 1/2 inch thick by 2 inches wide. 
>> We had some leaks at the fittings, which didn't make any sense. So I started 
>> stacking this stuff up and cutting it on the bandsaw and making end-grain 
>> balsa. I was doing that on Constitution Street when Alex Lippay and Bob 
>> Levine came in from Baltek. They said "What are you doing". I sadi "I got to 
>> turn this stuff the other way to stop the water from spreading. They said 
>> "Jeez, this is what we should be doing." I said "You're right". That's how 
>> Contourkore started. They took the end-grain idea and made samples that we 
>> evaluated. They came up with a method of putting scrim on it and so forth. 
>> In hindsight, I should have applied for a patent. I think we were probably 
>> one of the first to use Contourkore, as early as 1963 in a race boat hull. 
>> THe new product was brought to market in 1963 and 1964, with Pearson as one 
>> of the its first few users and most vocal supporters. Indeed, in 1981, 
>> Pearson sank a 2-square-foot basl cored panel in Narragansett Bay, attached 
>> by change to his dock. After three years he removed the panel from the water 
>> and had it analyzed. The results? No water penetrated the balso more than 4 
>> mils."
>> 
>> Best,
>> 
>> Lisle
>> 
>> On Thu, Sep 16, 2021 at 4:23 PM CHARLES SCHEAFFER via CnC-List 
>>  wrote: 
>> "Balsa core" gets some bad press and I was interested in how it came into 
>> boating, especially C
>> 
>> After some research, I learned:
>> Making things with a core was first used by Egyptians three thousand years 
>> ago.  Veneers of precious wood over a core of cheaper wood extended the use 
>> of precious materials.  The practice was lost in the middle ages and 
>> re-imagined in the 1700's when furniture makers wanted to make things from 
>> scarce woods.  
>> 
>> Later in the 1920's and 30's, balsa core was being harvested in Equador by a 
>> French company trying to market it in France in the 20's and 30's.  The 
>> Jewish French owners fled the Nazi takeover and emigrated to the US.  Their 
>> balsa was later used by DeHaviland in England to build the famous Mosquito 
>> two engine bombers in 1941.  Dehavilland built over 7700 of these 400+ mph 
>> planes using two Spitfire engines each.   They used a plywood vaneer over an 
>> endgrain balsa core.  https://www.youtube.com/watch?v=JTsnMKzmdWs=613s 
>> 
>> The balsa industry lost a market after WWII but in the 70's, they convinced 
>> fiberglass boat builders to use balsa core and Hatteras sportfishing yachts 
>> were their first big client.  Almost all boat builders eventually started 
>> using balsa soon after, 

Stus-List Re: Balsa core history

[Neil Andersen via CnC-List]

Some of the new coring material (divinicell??) is supposed to address the 
balsa/foam issues.

Anyone with specific knowledge??

Neil Andersen
Rock Hall, MD 21661
484-354-8800

From: CHARLES SCHEAFFER via CnC-List 
Sent: Friday, September 17, 2021 10:39:29 AM
To: Stus-List 
Cc: CHARLES SCHEAFFER 
Subject: Stus-List Re: Balsa core history

That's a great story about Pearson starting the end grain orientation.  I 
wonder if that's 100% true.  I'll bet several others would have thought of that 
as well.  Anyone who works with wood knows the compression strength is best 
when wood grain is oriented that way.  Honeycomb cores are end grain oriented 
for the same reason.

I read an article I can't seem to find again, that compared balsa to foam as 
coring and they determined the balsa was better; stronger bond because the end 
grain wicks up resin, lower cost, better for the environment too, as it's a 
renewable source.  Coosa board has better water resistance but it's so much 
more expensive; it comes in sheets that add to shipping costs.  ContourKore 
Balsa is a series of cut squares, attached to a scrim that can be rolled so it 
packs into a smaller package and ships for less.  I used balsa to replace wet 
core on my boat.  Some of the wet balsa still had a very strong hold on the 
fiberglass, and I had to use a chisel to pry it loose and an angle grinder to 
smooth the remnants off.  Pretty amazing stuff.

Chuck S


On 09/16/2021 6:21 PM Lisle Kingery, PhD via CnC-List  
wrote:


FWIW, this prompted me to take a look at the book "Heart of Glass: Fiberglass 
boats and the men who made them": and some info on Balsa is on p122,

"Balsa Core. The Baltek Corporation was the exclusive supplier to powerboat 
builders of balsa planks for stiffening hull sides and bottoms. When balsa was 
originally supplied in lengths with the grain running longitudinally, Pearson 
had problems with water migrating away from the point of entry at the deck 
hardware fasteners, causing delamination. Everett Perason recalls that "We were 
using pieces 3 feet long by 1/2 inch thick by 2 inches wide. We had some leaks 
at the fittings, which didn't make any sense. So I started stacking this stuff 
up and cutting it on the bandsaw and making end-grain balsa. I was doing that 
on Constitution Street when Alex Lippay and Bob Levine came in from Baltek. 
They said "What are you doing". I sadi "I got to turn this stuff the other way 
to stop the water from spreading. They said "Jeez, this is what we should be 
doing." I said "You're right". That's how Contourkore started. They took the 
end-grain idea and made samples that we evaluated. They came up with a method 
of putting scrim on it and so forth. In hindsight, I should have applied for a 
patent. I think we were probably one of the first to use Contourkore, as early 
as 1963 in a race boat hull. THe new product was brought to market in 1963 and 
1964, with Pearson as one of the its first few users and most vocal supporters. 
Indeed, in 1981, Pearson sank a 2-square-foot basl cored panel in Narragansett 
Bay, attached by change to his dock. After three years he removed the panel 
from the water and had it analyzed. The results? No water penetrated the balso 
more than 4 mils."

Best,

Lisle

On Thu, Sep 16, 2021 at 4:23 PM CHARLES SCHEAFFER via CnC-List 
mailto:cnc-list@cnc-list.com>> wrote:
"Balsa core" gets some bad press and I was interested in how it came into 
boating, especially C

After some research, I learned:
Making things with a core was first used by Egyptians three thousand years ago. 
 Veneers of precious wood over a core of cheaper wood extended the use of 
precious materials.  The practice was lost in the middle ages and re-imagined 
in the 1700's when furniture makers wanted to make things from scarce woods.

Later in the 1920's and 30's, balsa core was being harvested in Equador by a 
French company trying to market it in France in the 20's and 30's.  The Jewish 
French owners fled the Nazi takeover and emigrated to the US.  Their balsa was 
later used by DeHaviland in England to build the famous Mosquito two engine 
bombers in 1941.  Dehavilland built over 7700 of these 400+ mph planes using 
two Spitfire engines each.   They used a plywood vaneer over an endgrain balsa 
core.  https://www.youtube.com/watch?v=JTsnMKzmdWs=613s

The balsa industry lost a market after WWII but in the 70's, they convinced 
fiberglass boat builders to use balsa core and Hatteras sportfishing yachts 
were their first big client.  Almost all boat builders eventually started using 
balsa soon after, including C, Pearson, Santana, Cape Dory, Columbia, 
Catalina, Hunter, Olsen, Saber, Schock, J-Boats, Beneteau, Jeanneau, as well as 
all the power boat builders, too.  
https://www.company-histories.com/Baltek-Corporation-Company-History.html

Core comparisons:
https://www.cruisingworld.com/how/inner-layer-core-materials-sailboat-construction/

I personally think C 

Stus-List Re: Balsa core history

[Richard Bush via CnC-List]

 Joe, thanks, that makes perfect sense to me! 
 
Richard
 s/v Bushmark4: 1985 C 37, Ohio River, Mile 584;
Richard N. Bush Law Offices 
2950 Breckenridge Lane, Suite Nine 
Louisville, Kentucky 40220-1462 
502-584-7255 
 
-Original Message-
From: Della Barba, Joe via CnC-List 
To: Stus-List 
Cc: Della Barba, Joe 
Sent: Fri, Sep 17, 2021 10:18 am
Subject: Stus-List Re: Balsa core history

 Time: I doubt anyone really thought through what balsa 
core would be like when it was 50-60-70 or more years old. A lot of things can 
go wrong with a lot of materials when past the half-century mark and headed 
towards 100.* Bad Builders:  Some builders, mostly NOT C, were or are 
infamous for doing things wrong and having issues with relatively new boats. 
Bad Owners: One unsealed thru-hull can eventually do a lot of damage.    * Our 
club uses Boston Whalers and we go through them. They eventually get saturated 
and weak, we send them to the dumpster, and get another one. Boston Whaler is a 
top builder and builds good boats, but decades of having the crap beat out of 
them eventually does them in, especially if any hull penetrations are not fixed 
ASAP. My Whaler is 51 years old and is still dry, it has never been a club boat 
and thus not beat like a rented mule by teenaged instructors. Note that the 
foam core in Whalers is MUCH WORSE than balsa once it gets wet. Water migrated 
through end-grain balsa, but it really tear up foam. I once went to put a 
thru-hull in a foam-core Krogen 42 and I got more than 50 gallons out of the 
core draining from the hole! That boat was essentially beyond repair, so it 
essentially got restricted to sheltered waters from then on.    Joe Coquina     
     From: Richard Bush via CnC-List 
Sent: Friday, September 17, 2021 9:18 AM
To: cnc-list@cnc-list.com
Cc: cscheaf...@comcast.net; Richard Bush 
Subject: [EXTERNAL] Stus-List Re: Balsa core history    Great info and 
research; so, how did balsa go from "wonder" material to;  "bad stuff don't 
touch..."? Thanks to all of the subscribers that contributed to the list to 
help with the costs involved.  If you want to show your support to the list - 
use PayPal to send contribution --  https://www.paypal.me/stumurray  Thanks - 
StuThanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[CHARLES SCHEAFFER via CnC-List]

That's a great story about Pearson starting the end grain orientation.  I 
wonder if that's 100% true.  I'll bet several others would have thought of that 
as well.  Anyone who works with wood knows the compression strength is best 
when wood grain is oriented that way.  Honeycomb cores are end grain oriented 
for the same reason.

I read an article I can't seem to find again, that compared balsa to foam as 
coring and they determined the balsa was better; stronger bond because the end 
grain wicks up resin, lower cost, better for the environment too, as it's a 
renewable source.  Coosa board has better water resistance but it's so much 
more expensive; it comes in sheets that add to shipping costs.  ContourKore 
Balsa is a series of cut squares, attached to a scrim that can be rolled so it 
packs into a smaller package and ships for less.  I used balsa to replace wet 
core on my boat.  Some of the wet balsa still had a very strong hold on the 
fiberglass, and I had to use a chisel to pry it loose and an angle grinder to 
smooth the remnants off.  Pretty amazing stuff.

Chuck S



> On 09/16/2021 6:21 PM Lisle Kingery, PhD via CnC-List 
>  wrote:
> 
> 
> FWIW, this prompted me to take a look at the book "Heart of Glass: 
> Fiberglass boats and the men who made them": and some info on Balsa is on 
> p122,
> 
> "Balsa Core. The Baltek Corporation was the exclusive supplier to 
> powerboat builders of balsa planks for stiffening hull sides and bottoms. 
> When balsa was originally supplied in lengths with the grain running 
> longitudinally, Pearson had problems with water migrating away from the point 
> of entry at the deck hardware fasteners, causing delamination. Everett 
> Perason recalls that "We were using pieces 3 feet long by 1/2 inch thick by 2 
> inches wide. We had some leaks at the fittings, which didn't make any sense. 
> So I started stacking this stuff up and cutting it on the bandsaw and making 
> end-grain balsa. I was doing that on Constitution Street when Alex Lippay and 
> Bob Levine came in from Baltek. They said "What are you doing". I sadi "I got 
> to turn this stuff the other way to stop the water from spreading. They said 
> "Jeez, this is what we should be doing." I said "You're right". That's how 
> Contourkore started. They took the end-grain idea and made samples that we 
> evaluated. They cam
 e up with a method of putting scrim on it and so forth. In hindsight, I should 
have applied for a patent. I think we were probably one of the first to use 
Contourkore, as early as 1963 in a race boat hull. THe new product was brought 
to market in 1963 and 1964, with Pearson as one of the its first few users and 
most vocal supporters. Indeed, in 1981, Pearson sank a 2-square-foot basl cored 
panel in Narragansett Bay, attached by change to his dock. After three years he 
removed the panel from the water and had it analyzed. The results? No water 
penetrated the balso more than 4 mils."
> 
> Best,
> 
> Lisle
> 
> On Thu, Sep 16, 2021 at 4:23 PM CHARLES SCHEAFFER via CnC-List 
> mailto:cnc-list@cnc-list.com > wrote:
> 
> > > "Balsa core" gets some bad press and I was interested in 
> how it came into boating, especially C
> > 
> > After some research, I learned:
> > Making things with a core was first used by Egyptians three 
> > thousand years ago.  Veneers of precious wood over a core of cheaper wood 
> > extended the use of precious materials.  The practice was lost in the 
> > middle ages and re-imagined in the 1700's when furniture makers wanted to 
> > make things from scarce woods.  
> > 
> > Later in the 1920's and 30's, balsa core was being harvested in 
> > Equador by a French company trying to market it in France in the 20's and 
> > 30's.  The Jewish French owners fled the Nazi takeover and emigrated to the 
> > US.  Their balsa was later used by DeHaviland in England to build the 
> > famous Mosquito two engine bombers in 1941.  Dehavilland built over 7700 of 
> > these 400+ mph planes using two Spitfire engines each.   They used a 
> > plywood vaneer over an endgrain balsa core.  
> > https://www.youtube.com/watch?v=JTsnMKzmdWs=613s
> > 
> > The balsa industry lost a market after WWII but in the 70's, they 
> > convinced fiberglass boat builders to use balsa core and Hatteras 
> > sportfishing yachts were their first big client.  Almost all boat builders 
> > eventually started using balsa soon after, including C, Pearson, Santana, 
> > Cape Dory, Columbia, Catalina, Hunter, Olsen, Saber, Schock, J-Boats, 
> > Beneteau, Jeanneau, as well as all the power boat builders, too.  
> > https://www.company-histories.com/Baltek-Corporation-Company-History.html
> > 
> > Core comparisons:
> > 
> > https://www.cruisingworld.com/how/inner-layer-core-materials-sailboat-construction/
> > 
> > I personally think C did an industry leading job to perfect the 
> > process using fiberglass and 

Stus-List Re: Balsa core history

[Joe Della Barba via CnC-List]

Some fiberglass AIRPLANES have suffered from blistering and these are 
landplanes, not flying boats sitting on a mooring. Even humid air can 
eventually do it.

I am glad my 35 is a solid hull now she is headed for 50 years old. It would be 
nice to have the stiffness and insulation of balsa, but I worry less about hull 
issues.

Speaking of tanks, the wood supporting my fuel tank rotted due to condensation 
from the tank. It now rests on starboard.

 

 

Joe Della Barba

Coquina C 35 MK I

Kent Island MD USA

 

 

 

From: Matthew via CnC-List  
Sent: Friday, September 17, 2021 10:25 AM
To: 'Stus-List' 
Cc: Matthew 
Subject: Stus-List Re: Balsa core history

 

That is not a safe assumption.  We did extensive repairs to the core below the 
waterline on my Custom 42, including from the keel back and the keel forward.  
Arguably, water in these areas resulted from failing to isolate thru-hulls and 
the prop shaft strut.  Two areas we did not consider, because there is no 
access point like a thru-hull, was amidships (port and starboard).  When we 
completed the work, we put over 10 coats of barrier coat on the bottom.

 

About four years ago I noticed blistering amidships, both port and starboard.  
You would think this is impossible – there is no way water got through all 
those barrier coats.  To access these areas, we needed to remove the water 
tanks on both sides and the diesel fuel tank (starboard).  Our conclusion, 
after scratching our heads, was that constant condensation under the tanks for 
45 years resulted in the core getting wet from the inside.  The inside glass 
was very thin in much of these areas.

 

There may be no bad balsa, but construction techniques can be a factor.  And 
there is water, and there is time.

 

Matt

 

From: Hoyt, Mike via CnC-List mailto:cnc-list@cnc-list.com> > 
Sent: Friday, September 17, 2021 9:21 AM
To: 'Stus-List' mailto:cnc-list@cnc-list.com> >
Cc: Hoyt, Mike mailto:mike.h...@impgroup.com> >
Subject: Stus-List Re: Balsa core history

 

There is no bad balsa.  Only bad owners (or prior owners)

 

I think it is safe to say that pretty much all water saturation of balsa is 
caused by poor bedding of  fittings

 

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[Matthew via CnC-List]

That is not a safe assumption.  We did extensive repairs to the core below the 
waterline on my Custom 42, including from the keel back and the keel forward.  
Arguably, water in these areas resulted from failing to isolate thru-hulls and 
the prop shaft strut.  Two areas we did not consider, because there is no 
access point like a thru-hull, was amidships (port and starboard).  When we 
completed the work, we put over 10 coats of barrier coat on the bottom.

 

About four years ago I noticed blistering amidships, both port and starboard.  
You would think this is impossible – there is no way water got through all 
those barrier coats.  To access these areas, we needed to remove the water 
tanks on both sides and the diesel fuel tank (starboard).  Our conclusion, 
after scratching our heads, was that constant condensation under the tanks for 
45 years resulted in the core getting wet from the inside.  The inside glass 
was very thin in much of these areas.

 

There may be no bad balsa, but construction techniques can be a factor.  And 
there is water, and there is time.

 

Matt

 

From: Hoyt, Mike via CnC-List  
Sent: Friday, September 17, 2021 9:21 AM
To: 'Stus-List' 
Cc: Hoyt, Mike 
Subject: Stus-List Re: Balsa core history

 

There is no bad balsa.  Only bad owners (or prior owners)

 

I think it is safe to say that pretty much all water saturation of balsa is 
caused by poor bedding of  fittings

 

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: [EXTERNAL] Re: Balsa core history

[Della Barba, Joe via CnC-List]

Typo
Water migrates slowly through end-grain balsa but really tears foam up

From: Della Barba, Joe via CnC-List 
Sent: Friday, September 17, 2021 10:18 AM
To: Stus-List 
Cc: Della Barba, Joe 
Subject: [EXTERNAL] Stus-List Re: Balsa core history

Time: I doubt anyone really thought through what balsa core would be like when 
it was 50-60-70 or more years old. A lot of things can go wrong with a lot of 
materials when past the half-century mark and headed towards 100.*
Bad Builders:  Some builders, mostly NOT C, were or are infamous for doing 
things wrong and having issues with relatively new boats.
Bad Owners: One unsealed thru-hull can eventually do a lot of damage.

* Our club uses Boston Whalers and we go through them. They eventually get 
saturated and weak, we send them to the dumpster, and get another one. Boston 
Whaler is a top builder and builds good boats, but decades of having the crap 
beat out of them eventually does them in, especially if any hull penetrations 
are not fixed ASAP. My Whaler is 51 years old and is still dry, it has never 
been a club boat and thus not beat like a rented mule by teenaged instructors. 
Note that the foam core in Whalers is MUCH WORSE than balsa once it gets wet. 
Water migrated through end-grain balsa, but it really tear up foam. I once went 
to put a thru-hull in a foam-core Krogen 42 and I got more than 50 gallons out 
of the core draining from the hole! That boat was essentially beyond repair, so 
it essentially got restricted to sheltered waters from then on.

Joe
Coquina



From: Richard Bush via CnC-List 
mailto:cnc-list@cnc-list.com>>
Sent: Friday, September 17, 2021 9:18 AM
To: cnc-list@cnc-list.com
Cc: cscheaf...@comcast.net; Richard Bush 
mailto:bushma...@aol.com>>
Subject: [EXTERNAL] Stus-List Re: Balsa core history

Great info and research; so, how did balsa go from "wonder" material to;  "bad 
stuff don't touch..."?
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[Della Barba, Joe via CnC-List]

Time: I doubt anyone really thought through what balsa core would be like when 
it was 50-60-70 or more years old. A lot of things can go wrong with a lot of 
materials when past the half-century mark and headed towards 100.*
Bad Builders:  Some builders, mostly NOT C, were or are infamous for doing 
things wrong and having issues with relatively new boats.
Bad Owners: One unsealed thru-hull can eventually do a lot of damage.

* Our club uses Boston Whalers and we go through them. They eventually get 
saturated and weak, we send them to the dumpster, and get another one. Boston 
Whaler is a top builder and builds good boats, but decades of having the crap 
beat out of them eventually does them in, especially if any hull penetrations 
are not fixed ASAP. My Whaler is 51 years old and is still dry, it has never 
been a club boat and thus not beat like a rented mule by teenaged instructors. 
Note that the foam core in Whalers is MUCH WORSE than balsa once it gets wet. 
Water migrated through end-grain balsa, but it really tear up foam. I once went 
to put a thru-hull in a foam-core Krogen 42 and I got more than 50 gallons out 
of the core draining from the hole! That boat was essentially beyond repair, so 
it essentially got restricted to sheltered waters from then on.

Joe
Coquina



From: Richard Bush via CnC-List 
Sent: Friday, September 17, 2021 9:18 AM
To: cnc-list@cnc-list.com
Cc: cscheaf...@comcast.net; Richard Bush 
Subject: [EXTERNAL] Stus-List Re: Balsa core history

Great info and research; so, how did balsa go from "wonder" material to;  "bad 
stuff don't touch..."?
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[Hoyt, Mike via CnC-List]

There is no bad balsa.  Only bad owners (or prior owners)

I think it is safe to say that pretty much all water saturation of balsa is 
caused by poor bedding of  fittings

From: Richard Bush via CnC-List 
Sent: September 17, 2021 10:18 AM
To: cnc-list@cnc-list.com
Cc: cscheaf...@comcast.net; Richard Bush 
Subject: Stus-List Re: Balsa core history

Great info and research; so, how did balsa go from "wonder" material to;  "bad 
stuff don't touch..."?

Richard
s/v Bushmark4; 1985 C 37 CB; Ohio River, Mile 584;
Richard N. Bush Law Offices
2950 Breckenridge Lane, Suite Nine
Louisville, Kentucky 40220-1462
502-584-7255


-Original Message-
From: CHARLES SCHEAFFER via CnC-List 
mailto:cnc-list@cnc-list.com>>
To: Stus-List mailto:cnc-list@cnc-list.com>>
Cc: CHARLES SCHEAFFER mailto:cscheaf...@comcast.net>>
Sent: Thu, Sep 16, 2021 6:06 pm
Subject: Stus-List Re: Balsa core history
Hey JohnKelly,
Hopefully, Rob Mazza will share some info on this.

I imagine C did considerable testing to determine the strength of their 
construction to evaluate laminate schedules and optimum core thickness.  Do you 
remember seeing any letters in your binders explaining the testing done, data 
collected, etc?

Chuck S


On 09/16/2021 5:34 PM JohnKelly Cuthbertson via CnC-List 
mailto:cnc-list@cnc-list.com>> wrote:


Rob Mazza is the expert in this specific topic

JK
Motion Designs Limited
647 990 7752

, but that is better covered by John Kelly Cuthbertson or others with more 
personal knowledge.



Chuck Scheaffer, Resolute, 1989 C 34R, Annapolis
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved. If you want to show your support to the list - use PayPal to 
send contribution -- https://www.paypal.me/stumurray Thanks - Stu
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --  https://www.paypal.me/stumurray Thanks - Stu
Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[Richard Bush via CnC-List]

 Great info and research; so, how did balsa go from "wonder" material to;  "bad 
stuff don't touch..."? 
 
Richard
 s/v Bushmark4; 1985 C 37 CB; Ohio River, Mile 584; 
Richard N. Bush Law Offices 
2950 Breckenridge Lane, Suite Nine 
Louisville, Kentucky 40220-1462 
502-584-7255 
 
-Original Message-
From: CHARLES SCHEAFFER via CnC-List 
To: Stus-List 
Cc: CHARLES SCHEAFFER 
Sent: Thu, Sep 16, 2021 6:06 pm
Subject: Stus-List Re: Balsa core history

  Hey JohnKelly, 
   Hopefully, Rob Mazza will share some info on this.
   
   I imagine C did considerable testing to determine the strength of their 
construction to evaluate laminate schedules and optimum core thickness.  Do you 
remember seeing any letters in your binders explaining the testing done, data 
collected, etc?
   
   Chuck S
   
   
  
  On 09/16/2021 5:34 PM JohnKelly Cuthbertson via CnC-List 
 wrote:   
   
 Rob Mazza is the expert in this specific topic   
   JK 
 
  Motion Designs Limited  647 990 7752
   , but that is better covered by John Kelly Cuthbertson or others with more 
personal knowledge.  

   
   
   
   Chuck Scheaffer, Resolute, 1989 C 34R, Annapolis   

 Thanks to all of the subscribers that contributed to the list to help with the 
costs involved. If you want to show your support to the list - use PayPal to 
send contribution -- https://www.paypal.me/stumurray Thanks - Stu 
 Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --  https://www.paypal.me/stumurray  Thanks - StuThanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

Stus-List Re: Balsa core history

[Matthew via CnC-List]

Unfortunately, I’ve become somewhat of an expert myself.

 

From: JohnKelly Cuthbertson via CnC-List  
Sent: Thursday, September 16, 2021 5:34 PM
To: Stus-List 
Cc: JohnKelly Cuthbertson 
Subject: Stus-List Re: Balsa core history

 

Rob Mazza is the expert in this specific topic 

 

JK

Motion Designs Limited

647 990 7752

Thanks to all of the subscribers that contributed to the list to help with the 
costs involved.  If you want to show your support to the list - use PayPal to 
send contribution --   https://www.paypal.me/stumurray  Thanks - Stu