I'm loving your input gentleman,

I agree completely. I come from a construction background so plan on using a 
cement type of mortar used for anchoring large industrial equipment. Once fully 
cured it has a load rating of 8100 lbs/sq in, doesn't shrink and is unaffected 
by water. I was certain the loads wouldn't exceed that but wanted to make sure. 
 My plan going forward once excavated was to pour 4-5 " of the mortar to level 
up the base and then fabricate a steel post with a bottom and top plate with a 
hole for the forward keel bolt to hold everything in place and then glass in 
the top. I was tempted to just fill the entire cavity with the mortar and move 
on but thought the compression post was a better plan.........until I read what 
your father said. Maybe he's right, top it up and call it a day.

The mortar I plan to use is called Sikagrout 212 but states that after 6" of 
depth you need an aggregate filler. Maybe something with less weight could be 
used to retain strength in the grout and filling the cavity would definitely be 
the way to go.
Thought?

Greg


On Jun 28, 2017, at 7:35 AM, Dave S via CnC-List 
<cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>> wrote:

Greg - agreed with Russ (and Joe.)  When I did mine I briefly went down the 
calculation rabbit hole, looking at the properties of materials etc and I 
realized there was no way for me to calculate the hypothetical combined load of 
keel bolt torque, mast/rig, and one bolt's worth of bashing a rock at 4kts.   
My brain elected to look at the original construction and make it stronger 
(compression posts, epoxy, carbon fibre....) and move on to other projects.   I 
used glass and carbon fibre (recommended by the local composites purveyor) 
instead of AL as others have done, but,  same idea.   My dad (builder of many 
boats- now in NS) suggested concrete as fill and he was probably right.

Dave



---------- Forwarded message ----------
From: "Russ & Melody" <russ...@telus.net<mailto:russ...@telus.net>>
To: cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>
Cc:
Bcc:
Date: Tue, 27 Jun 2017 21:52:15 -0700
Subject: Re: Stus-List 33 mk2 Mast step loads

Hi Dave,

Watch those units.
4000 PSI on a 6" x 8" mast step plane is out of this world for a 33 foot boat.
When I did the mast loading while designing the rig of my old 60' cruiser it 
was 100,000 lbs and he's telling you it's twice that??

I would go with Joe's suggestion of 1/2" aluminum plate and move on to other 
projects.

        Cheers, Russ
        Sweet 35 mk-1

At 08:24 AM 27/06/2017, you wrote:
Content-Language: en-CA
Content-Type: multipart/alternative;
         
boundary="_000_BY2PR02MB458E0206231C27457085F24B1DC0BY2PR02MB458namprd_"

Thanks everyone for the info. I spoke with Danny from Klacko spars yesterday 
and he's certain that he would have installed my original mast in '87. He 
figures even when falling into a wave with full sails the forces wouldn't 
exceed 4000 psi. Seems light to me but who am I to argue with him.
I thought I notice Mr. Knowles at the club on the weekend so I'll definitely 
run it past him - thanks for mentioning that.

I have the entire mast step "excavated" to the keel and am starting the 
rebuild. Can't wait for this one to be finished!

Thanks!
Greg
33 mk2
Halifax

On Jun 27, 2017, at 10:52 AM, Della Barba, Joe via CnC-List 
<cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>> wrote:

I used a total of ½†  aluminum on mine when I rebuilt it. It looks about 20 
times stronger than the original was too.

Joe
Coquina
CC&C 35 MK I
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