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Ideal bar length of home made cam clamps?
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Author:  Jimmyjames [ Tue Mar 24, 2015 10:19 pm ]
Post subject:  Ideal bar length of home made cam clamps?

I'm going to make all of my cam clamps and the bar will also be made of wood. Obviously, I'm making these specifically for acoustic guitar making and would like to know how much sliding length is needed?

What's the ideal number of clamps:

8"?

6"?

4"?

Is there also an ideal width of the clamping points?

Thanks,

-jj

Author:  Tom West [ Wed Mar 25, 2015 2:03 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

Jimmy: Not in the workshop right now so can't give you a measurement. The largest gap I need is for the depth of the sound box. Saying that one adds extra for the use of cauls. I also have clamps with shorter bars for brace clamping. My longest bars are certainly longer then your longest quote. However many clamps you are making.............DOUBLE IT.......you can't have too many clamps, at least I can't.
Tom

Author:  Jimmyjames [ Wed Mar 25, 2015 2:18 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

I was going to start with 16 total cam clamps:

Eight 4"

Four 6"

Four 8"

It really adds up to a staggering amount of material.

Author:  edstrummer [ Wed Mar 25, 2015 6:44 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

Rockler has their eight inch cam clamps on sale for half price this month. Under eight bucks each. They work fine. Buying two more today. Four inch clamps were on sale last month. Also under eight bucks each.


Sent from my iPhone using Tapatalk

Author:  Glenn_Aycock [ Wed Mar 25, 2015 6:53 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

$8 is pretty reasonable for the time involved. I think I used 12" because I bought a 4' stick and made 4.

Image

http://glennaycockwoodworking.blogspot.com/2010/02/deep-throat-guitar-makers-clamps.html

Author:  Hesh [ Wed Mar 25, 2015 7:02 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

Welcome Jimmy: Be sure to check out the idea of using a go-bar deck for clamping and when and if you do it may impact how many cam clamps you need. It most certainly did with me.

Author:  Jimmyjames [ Wed Mar 25, 2015 10:05 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

The Rockler sale is remarkably cheap. I'm spending sooo much money already. Cutting every corner I can I'm already at $1,500 in materials and tools for what will potentially be a poor quality guitar due to inexperience. Plus at least $10,000 worth of hand tools, equipment, making my bench, et cetera. Building a guitar is expensive.

My shop has a shed roof (slanted) but I could potentially use go bars. I'll have to investigate.

Thanks for the heads up.

-jj

Author:  DennisK [ Wed Mar 25, 2015 11:57 am ]
Post subject:  Re: Ideal bar length of home made cam clamps?

IMO, bare minimum for gluing an X brace is 7 clamps total.

I have three 4", four 6", three 8", and am pretty happy. But I have been thinking about making a go-bar deck as well.

Bar length on mine is 12" (9" maximum distance between jaws), but I hardly ever need that much, and long bars are heavy, which can be a problem if you have the clamp hanging from a flexible guitar part (e.g. gluing a bridge).

But I would like to have a couple really long ones that can reach all the way across a guitar for squeezing out binding gaps. Squeezing gaps on ukuleles is one of the places I do need the reach of my current clamps.

Author:  Jimmyjames [ Wed Mar 25, 2015 12:04 pm ]
Post subject:  Re: Ideal bar length of home made cam clamps?

Thanks Dennis. I think I'll make eight to that spec. What's an ideal width of the clamp? I was just going to do half inch wide as we're talking about low clamping pressures but I don't really know what's required.

I'm reasonably certain you can get a longer bar, pop out the pins, in your shorter clamp and change the bar. Voila!

Author:  Glenn_Aycock [ Wed Mar 25, 2015 2:10 pm ]
Post subject:  Re: Ideal bar length of home made cam clamps?

JJ,

I feel your pain. My first acoustic cost me about $5k, but I already had most of the tools. :-(

Go-bar deck can be made for about $35 http://glennaycockwoodworking.blogspot.com/2010/02/go-bar-deck.html

Author:  DennisK [ Wed Mar 25, 2015 3:05 pm ]
Post subject:  Re: Ideal bar length of home made cam clamps?

Jimmyjames wrote:
Thanks Dennis. I think I'll make eight to that spec. What's an ideal width of the clamp? I was just going to do half inch wide as we're talking about low clamping pressures but I don't really know what's required.

I suppose ideal depends on the task and personal preference. Mine are a little under 1" wide, and I wouldn't change it if I was making my own. I like having plenty of contact area regardless of the direction I'm clamping from. But if you think you'd prefer 1/2", by all means go with it. The lighter weight would be nice, plus it's less material to make them :) And a narrower jaw can clamp in concave spots where a wide jaw would need a curved caul.

Author:  Ruby50 [ Wed Mar 25, 2015 9:16 pm ]
Post subject:  Re: Ideal bar length of home made cam clamps?

We made 20 for my daughter's new repair shop a year ago, and at that time S-M had just come out with their mini-clamps. The big guys have 1" wide jaws, but the mini's have 1/2". We did some of each. We also made a couple of them with 24" bars (1/2 of a 48" hardware store aluminum bar) to reach across the top or back of an instrument. We also varied the length of the jaws. Don't make the smaller ones (1/8" X 3/4" aluminum bar) longer than about 12" because the bar has too much flex for them to tighten up.

Here is what the small ones look like compared to the big ones:

https://www.flickr.com/photos/ruby1638/11143067386/in/set-72157638227649784

Ed

Author:  Bob Shanklin [ Thu Mar 26, 2015 4:55 pm ]
Post subject:  Re: Ideal bar length of home made cam clamps?

+1 what Hesh said. And check out Kathy Matsushita's swivel deck.
http://www.theamateurluthier.com/movies/gobarswivel.mov

Bob

Author:  RustySP [ Thu Mar 26, 2015 6:01 pm ]
Post subject:  Re: Ideal bar length of home made cam clamps?

I've bought Dubuque, Stew-Mac, and Klemmsia, if I buy more cam clamps they will be Klemmsia. I just like them better.

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