Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Kirk Wallace 

On 07/31/2017 02:59 PM, Chris Albertson wrote:

Someone here might know where to get the thin heater wire (insulated

nichrome?) to rebuild the linked gauge CVR?



Locally, try "smoke shops"   People into e-cirgaretts use this wire.  It
comes in different gauges.Amazon sells the same wire for the same use


It seems that Kanthal A series (FeCrAl) forms an aluminum oxide skin 
which is an electrical insulator.

https://en.wikipedia.org/wiki/Kanthal_(alloy)

From the size and number of turns, 30 on the bi-metal arm @ .125" wide 
= 7.5", and measuring a 0.004" diameter or 38 gauge and 53 Ohms per 
foot, I get 33 Ohms which matches what I measured while troubleshooting 
the instruments early on. This should do it:

http://www.ebay.com/itm/282229270564

with a lot left over.


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http://www.wallacecompany.com/E45/

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Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Todd Zuercher 
My dad had a Scout II when I was a kid.  I thought it was pretty cool back 
then.  I've heard most of their rust problems stemmed from the insides of the 
body panels not even being painted.  Very durable trucks otherwise.  I also 
heard a story, an IH line worker said to a co-worker as he finished his can of 
pop "This will drive someone crazy" then threw the can into the body and 
screwed the panel shut. 

- Original Message -
From: "Kirk Wallace" 
To: emc-users@lists.sourceforge.net
Sent: Monday, July 31, 2017 9:54:34 PM
Subject: Re: [Emc-users] Fwd: Way OT: Heater Wire

On 07/31/2017 04:04 PM, Dave Cole wrote:
> That Scout probably has that half a V8 engine..  its a slant 4 engine
> with about 200 cu inches?
> I believe that was made not too far from my house in Fort Wayne, IN.
> I almost bought one of those back in the late 70's.
> They rusted like crazy in the midwest.  Rust prevention was an after
> thought back then.
> There are still a few of those running around here.
> I'd ditch that device.   Otherwise you will be rebuilding it again.
>
> Dave

Part of my thinking is that what's the point of having an old car if one 
upgrades all of the parts. The owner prefers using the upgrade, but I 
thought if I could figure out the restoration issues without too much 
trouble it might be fun to restore the CVR and have the option. To 
totally upgrade the CVR it might be fun to use something like a Teensy 
to simulate the old one.

This IH Scout has a V8, but I don't know any of the particulars. I'll 
ask the owner what kind it is and maybe link some pictures if that is 
alright.


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http://www.wallacecompany.com/E45/

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Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Kirk Wallace 

On 07/31/2017 04:04 PM, Dave Cole wrote:

That Scout probably has that half a V8 engine..  its a slant 4 engine
with about 200 cu inches?
I believe that was made not too far from my house in Fort Wayne, IN.
I almost bought one of those back in the late 70's.
They rusted like crazy in the midwest.  Rust prevention was an after
thought back then.
There are still a few of those running around here.
I'd ditch that device.   Otherwise you will be rebuilding it again.

Dave


Part of my thinking is that what's the point of having an old car if one 
upgrades all of the parts. The owner prefers using the upgrade, but I 
thought if I could figure out the restoration issues without too much 
trouble it might be fun to restore the CVR and have the option. To 
totally upgrade the CVR it might be fun to use something like a Teensy 
to simulate the old one.


This IH Scout has a V8, but I don't know any of the particulars. I'll 
ask the owner what kind it is and maybe link some pictures if that is 
alright.



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http://www.wallacecompany.com/machine_shop/
http://www.wallacecompany.com/E45/

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Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Dave Cole 
That Scout probably has that half a V8 engine..  its a slant 4 engine 
with about 200 cu inches?

I believe that was made not too far from my house in Fort Wayne, IN.
I almost bought one of those back in the late 70's.
They rusted like crazy in the midwest.  Rust prevention was an after 
thought back then.

There are still a few of those running around here.
I'd ditch that device.   Otherwise you will be rebuilding it again.

Dave


On 7/31/2017 5:43 PM, Kirk Wallace wrote:

On 07/31/2017 02:00 PM, andy pugh wrote:
On 31 July 2017 at 21:47, Kirk Wallace  
wrote:



Someone here might know where to get the thin heater wire (insulated
nichrome?) to rebuild the linked gauge CVR?


How hot does it get? Could you wrap the part in Kapton tape and use
uninsulated wire?


I don't think it normally should get exceptionally hot, just enough to 
bend the bi-metal spring. Here is a link of a decent overview of CVR 
units:

http://www.minimania.com/Smiths_Voltage_Stabilizers

less elegant:
https://www.youtube.com/watch?v=0qVfKiujK5A
https://www.youtube.com/watch?v=a1ou2WHdylY=2s

The unit I'm working on is for a International Harvester Scout from 
the 60s. The bi-metal arm got too (blue) hot due to a dead short to 
ground on the CVR output which melted the supply wire (should have had 
a 14amp fuse according to the schematic).


We opened the can on this one and got it working again until the 
heater wire melted from shorting to the bi-metal spring.


The plan so far is to use a 5 Volt buck converter instead:
http://www.ebay.com/itm/45520202

It may not matter, but the temperature characteristics of the CVR are 
supposed to match the temperature characteristics of the gauges and 
with the proper heater wire it should be easy to rewind.





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Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Chris Albertson 
Someone here might know where to get the thin heater wire (insulated
> nichrome?) to rebuild the linked gauge CVR?
>

Locally, try "smoke shops"   People into e-cirgaretts use this wire.  It
comes in different gauges.Amazon sells the same wire for the same use

Here is one
https://www.amazon.com/Nichrome-Wire-Sample-Pack-Gauge/

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Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Kirk Wallace 

On 07/31/2017 02:00 PM, andy pugh wrote:

On 31 July 2017 at 21:47, Kirk Wallace  wrote:


Someone here might know where to get the thin heater wire (insulated
nichrome?) to rebuild the linked gauge CVR?


How hot does it get? Could you wrap the part in Kapton tape and use
uninsulated wire?


I don't think it normally should get exceptionally hot, just enough to 
bend the bi-metal spring. Here is a link of a decent overview of CVR units:

http://www.minimania.com/Smiths_Voltage_Stabilizers

less elegant:
https://www.youtube.com/watch?v=0qVfKiujK5A
https://www.youtube.com/watch?v=a1ou2WHdylY=2s

The unit I'm working on is for a International Harvester Scout from the 
60s. The bi-metal arm got too (blue) hot due to a dead short to ground 
on the CVR output which melted the supply wire (should have had a 14amp 
fuse according to the schematic).


We opened the can on this one and got it working again until the heater 
wire melted from shorting to the bi-metal spring.


The plan so far is to use a 5 Volt buck converter instead:
http://www.ebay.com/itm/45520202

It may not matter, but the temperature characteristics of the CVR are 
supposed to match the temperature characteristics of the gauges and with 
the proper heater wire it should be easy to rewind.



--
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http://www.wallacecompany.com/machine_shop/
http://www.wallacecompany.com/E45/

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Re: [Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread andy pugh 
On 31 July 2017 at 21:47, Kirk Wallace  wrote:

> Someone here might know where to get the thin heater wire (insulated
> nichrome?) to rebuild the linked gauge CVR?

How hot does it get? Could you wrap the part in Kapton tape and use
uninsulated wire?


-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916

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[Emc-users] Fwd: Way OT: Heater Wire

2017-07-31 Thread Kirk Wallace 




 Forwarded Message 
Subject: Way OT: Heater Wire
Date: Mon, 31 Jul 2017 13:36:59 -0700
From: Kirk Wallace 
To: Enhanced Machine Controller (EMC) 

Someone here might know where to get the thin heater wire (insulated 
nichrome?) to rebuild the linked gauge CVR?


link:
http://wallacecompany.com/IH_Scout/

--
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http://www.wallacecompany.com/machine_shop/
http://www.wallacecompany.com/E45/


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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Gregg Eshelman via Emc-users 
Look up the Dollo 3D printer. All the files are free to download. It 
includes pieces of herringbone rack and matching gears. Could have some 
examples printed then make molds and cast in high strength resin. Could 
also use the 3D files to 3D mill steel racks and gears.


-- Original Message --
From: "andy pugh" 
To: "Enhanced Machine Controller (EMC)" 


Sent: 7/31/2017 5:53:04 AM
Subject: Re: [Emc-users] Rack and pinion - tension or not


On 31 July 2017 at 12:13, Tomaz T.  wrote:
For my future project (cnc router) I will have to use helical rack and 
pinion system on two longer axis (2 and 3.5m). There are some designs 
where pinion is forced against rack with spring tensioner


It ocurred to me a while ago that if using a double-helical rack and
pinion then you can achieve zero backlash with an axial displacement
of the pinion/gear relative to the rack.
I don't know if anyone has ever done that.



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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Les Newell 



If they are pre-loading to full contact, I fail to  see the diff between
a spring load and a pre-load. With a spring, it might have enough give
to ride over a wood chip falling on the pinion.


The problem is that racks produce a significant force pushing the pinion 
out of mesh. If I remember it is about a third of the thrust. If you 
have a spring preload the pinion tends to end up climbing out of the 
rack teeth unless you use a really big spring. In that case you end up 
with wear problems or even broken teeth.


Les

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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread andy pugh 
On 31 July 2017 at 18:12, Gene Heskett  wrote:

>> http://nexengroup.com/nxn/products/prod-nav/lp/Roller+Pinion+System
>
> That I like.

It reminds me uncomfortably of:
http://c8.alamy.com/comp/F4RMG7/netherlands-europe-holland-westzaan-noord-holland-windmill-interior-F4RMG7.jpg

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916

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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Gene Heskett 
On Monday 31 July 2017 08:02:54 Reggie Crane wrote:

> Have you considered Nexen linear positioning systems?
>
> http://nexengroup.com/nxn/products/prod-nav/lp/Roller+Pinion+System

That I like. And I'd not be surprised to find that the racks can be 
butted together to get the effective lengths you would need for a 4x8 
working envelop. You would need 2 for that 4' width, you would have more 
than half of the 2nd in the cutoff, which would serve as the last 
extension filler for the 8' needed the long way.  Thats 4 for the 4', 
and 4 for the 8' run using the leftovers from the 4'. 8 racks total.

My $0.02. :)

> On Mon, Jul 31, 2017 at 6:53 AM, andy pugh  wrote:
> > On 31 July 2017 at 12:13, Tomaz T.  wrote:
> > > For my future project (cnc router) I will have to use helical rack
> > > and
> >
> > pinion system on two longer axis (2 and 3.5m). There are some
> > designs where pinion is forced against rack with spring tensioner
> >
> > It ocurred to me a while ago that if using a double-helical rack and
> > pinion then you can achieve zero backlash with an axial displacement
> > of the pinion/gear relative to the rack.
> > I don't know if anyone has ever done that.
> >
> > --
> > atp
> > "A motorcycle is a bicycle with a pandemonium attachment and is
> > designed for the especial use of mechanical geniuses, daredevils and
> > lunatics."
> > — George Fitch, Atlanta Constitution Newspaper, 1916

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Gene Heskett 
On Monday 31 July 2017 07:13:05 Tomaz T. wrote:

> For my future project (cnc router) I will have to use helical rack and
> pinion system on two longer axis (2 and 3.5m). There are some designs
> where pinion is forced against rack with spring tensioner, on the
> other side, if I follow Atlanta's installation manual for their
> system, they forbid tensioning pinion against rack as it would cause 
> wear and tear or rupture of teeth (they suggest pre-load pinion
> shaft).

If they are pre-loading to full contact, I fail to  see the diff between 
a spring load and a pre-load. With a spring, it might have enough give 
to ride over a wood chip falling on the pinion.

> In my case this will be used for woodworking cnc router, so I'm not
> looking for very high precision, but anyway if there is anyone heaving
> experience with this would be nice to hear.

Not with this per sei, but I found precise in woodcarving was a matter of 
taste, in my case when carving some green and green style box joints in 
mahogany.

In order to get a fit I could finish sand and draw or hammer together, I 
had to cheat on the fit by telling the machine the 1/4" bit I was using, 
was only about .247" in diameter, otherwise the fit was so tight it 
wiped all the glue off in front of it as I drove the joint together, and 
as the carbide bit dulled, I had to increase the clearance by telling 
the software the bit was as small as .245".  This was using the max 
speed the G0704's spindle could muster, about 2750 revs with my 
controller. A genuine router motor doing 25k rpms probably wouldn't have 
needed the extra clearance.

> Example of tensioned pinion:
>
> https://www.google.si/search?q=rack+pinion+cnc=lnms=isch
>=X=0ahUKEwi8g8ziqrPVAhVE6xoKHf02A3gQ_AUICigB=1536=735#imgrc
>=Yrj6s6vvjL--WM:

Looks good to me. I might use a longer, softer spring, or a tension 
spring, if adjustment needed, adjust the springs anchoring hook. One of 
the other pix at that link shows that IIRC.


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Bari 00000 
http://www.machinedesign.com/linear-motion/go-long-pros-and-cons-rack-and-pinion-systems

Another option are master and slave pinion drives:
https://servotak.eu/products/custom-products/zero-backlash-rack-pinion-gearbox-systems

On Mon, Jul 31, 2017 at 6:13 AM, Tomaz T.  wrote:

> For my future project (cnc router) I will have to use helical rack and
> pinion system on two longer axis (2 and 3.5m). There are some designs where
> pinion is forced against rack with spring tensioner, on the other side, if
> I follow Atlanta's installation manual for their system, they forbid
> tensioning pinion against rack as it would cause  wear and tear or rupture
> of teeth (they suggest pre-load pinion shaft).
>
> In my case this will be used for woodworking cnc router, so I'm not
> looking for very high precision, but anyway if there is anyone heaving
> experience with this would be nice to hear.
>
> Example of tensioned pinion:
>
> https://www.google.si/search?q=rack+pinion+cnc=lnms;
> tbm=isch=X=0ahUKEwi8g8ziqrPVAhVE6xoKHf02A
> 3gQ_AUICigB=1536=735#imgrc=Yrj6s6vvjL--WM:
>
> 
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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Les Newell 
Tensioning the gear against the rack works reasonably well for plasma 
cutters as they are lightly loaded. One problem is that gears generate a 
force that is trying to push them apart. If I remember correctly the 
generated force is about a third of the linear thrust. You end up having 
to use a lot of tension otherwise they lose accuracy or jump teeth.


 A router sees relatively high cutting forces so I wouldn't recommend 
tensioning. Assuming you are using fairly accurate rails, such as 
profile rails I would hard mount the pinion and adjust it so you can 
just feel a tiny amount of backlash. Check it over the whole travel. 
This will give long life while retaining reasonable accuracy. I have 
worked on plenty of commercial routers using this setup and they run all 
day for years with very few problems. You can use various preload 
techniques such as anti-backlash gears or two gears slightly out of 
phase but to be honest for a router I think they just increase wear with 
no noticeable improvement in part accuracy.


Les

On 31/07/2017 12:13, Tomaz T. wrote:

For my future project (cnc router) I will have to use helical rack and pinion 
system on two longer axis (2 and 3.5m). There are some designs where pinion is 
forced against rack with spring tensioner, on the other side, if I follow 
Atlanta's installation manual for their system, they forbid tensioning pinion 
against rack as it would cause  wear and tear or rupture of teeth (they suggest 
pre-load pinion shaft).

In my case this will be used for woodworking cnc router, so I'm not looking for 
very high precision, but anyway if there is anyone heaving experience with this 
would be nice to hear.



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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread andy pugh 
On 31 July 2017 at 13:42, Tomaz T.  wrote:
> Something like this would reduce backlash to "zero" (without gearbox):

> https://www.damencnc.com/products/mechanical-components/rack-pinion/r-p-drive-antibacklash-diy-includes-gears15t/_404_w_74_554_GB_1

Or 
http://www.hpcgears.com/n/products/8.anti-backlash_gears/anti_backlash_gears.php

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designed for the especial use of mechanical geniuses, daredevils and
lunatics."
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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Tomaz T . 
Something like this would reduce backlash to "zero" (without gearbox):


https://www.damencnc.com/products/mechanical-components/rack-pinion/r-p-drive-antibacklash-diy-includes-gears15t/_404_w_74_554_GB_1




>It ocurred to me a while ago that if using a double-helical rack and
>pinion then you can achieve zero backlash with an axial displacement
>of the pinion/gear relative to the rack.
>I don't know if anyone has ever done that.

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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread andy pugh 
On 31 July 2017 at 13:02, Reggie Crane  wrote:
> Have you considered Nexen linear positioning systems?
>
> http://nexengroup.com/nxn/products/prod-nav/lp/Roller+Pinion+System

I rather like the Servobelt idea. It should be much stiffer than a
conventional belt, for practially no extra cost. It is also
self-covering so should have good dust resitance.
http://www.bell-everman.com/products/linear-positioning/servobelt-linear-sbl


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designed for the especial use of mechanical geniuses, daredevils and
lunatics."
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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Reggie Crane 
Have you considered Nexen linear positioning systems?

http://nexengroup.com/nxn/products/prod-nav/lp/Roller+Pinion+System



On Mon, Jul 31, 2017 at 6:53 AM, andy pugh  wrote:

> On 31 July 2017 at 12:13, Tomaz T.  wrote:
> > For my future project (cnc router) I will have to use helical rack and
> pinion system on two longer axis (2 and 3.5m). There are some designs where
> pinion is forced against rack with spring tensioner
>
> It ocurred to me a while ago that if using a double-helical rack and
> pinion then you can achieve zero backlash with an axial displacement
> of the pinion/gear relative to the rack.
> I don't know if anyone has ever done that.
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1916
>
> 
> --
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> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Re: [Emc-users] Rack and pinion - tension or not

2017-07-31 Thread andy pugh 
On 31 July 2017 at 12:13, Tomaz T.  wrote:
> For my future project (cnc router) I will have to use helical rack and pinion 
> system on two longer axis (2 and 3.5m). There are some designs where pinion 
> is forced against rack with spring tensioner

It ocurred to me a while ago that if using a double-helical rack and
pinion then you can achieve zero backlash with an axial displacement
of the pinion/gear relative to the rack.
I don't know if anyone has ever done that.

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atp
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[Emc-users] Rack and pinion - tension or not

2017-07-31 Thread Tomaz T . 
For my future project (cnc router) I will have to use helical rack and pinion 
system on two longer axis (2 and 3.5m). There are some designs where pinion is 
forced against rack with spring tensioner, on the other side, if I follow 
Atlanta's installation manual for their system, they forbid tensioning pinion 
against rack as it would cause  wear and tear or rupture of teeth (they suggest 
pre-load pinion shaft).

In my case this will be used for woodworking cnc router, so I'm not looking for 
very high precision, but anyway if there is anyone heaving experience with this 
would be nice to hear.

Example of tensioned pinion:

https://www.google.si/search?q=rack+pinion+cnc=lnms=isch=X=0ahUKEwi8g8ziqrPVAhVE6xoKHf02A3gQ_AUICigB=1536=735#imgrc=Yrj6s6vvjL--WM:

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