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Main Boards => The Bowyer's Bench => Topic started by: Lee Lobbestael on March 28, 2017, 12:11:00 PM

Title: pressure strip
Post by: Lee Lobbestael on March 28, 2017, 12:11:00 PM
So i'm building a laminated r/d bow using Kenny's glass, lams and plans. He has been a huge help and I plan to start a build along here soon. I'm using the rubber innertube method for clamping and it was suggested to me that I use a pressure strip beneath the inner tubes. I'm planning to use thin strips of wood or something like that and I ordered 1/8" thick  adhesive backed rubber to stick to them. I feel this will even out the clamping pressure even more. My question is, should I also put thin rubber on the actual form or would this cause more problems than it would fix? I believe I have my form very smooth and square.
Thanks
Title: Re: pressure strip
Post by: Kamn on March 28, 2017, 12:44:00 PM
The thing to remember with the rubber band method is the pressure strip is flat which means the bands will exert most of the pressure on the outer edges of the strip, so you need something on top of the pressure strip that makes a high point in the middle of the pressure strip......I hope that makes sense?

I know that there are a few guys out there using rubber on the base of the form for the bow to sit on, maybe they will chime in on this for you
Title: Re: pressure strip
Post by: Buemaker on March 28, 2017, 12:59:00 PM
Something like this works.
 http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=125;t=012642#000000
Title: Re: pressure strip
Post by: Kamn on March 28, 2017, 01:32:00 PM
There yeah go ^^^
Title: Re: pressure strip
Post by: Lee Lobbestael on March 28, 2017, 04:10:00 PM
Thats a good idea Buemaker. I will add something to the middle of the pressure strip to get more even pressure. I have long strips of fairly hard rubber just over an inch wide. I think if I lay that on top of my pressure strips that should do the trick.
Title: Re: pressure strip
Post by: KenH on March 28, 2017, 04:26:00 PM
As a "rubber band guy", I agree with Bue -- use a pressure strip that is higher in the center than at the edges. I've never needed rubber under the lams and ontop of the form...
Title: Re: pressure strip
Post by: Bvas on March 28, 2017, 05:56:00 PM
I've only done two bows thus far. So am not an expert by any means. But this is what I used and worked for me.
No rubber on the form side. 1/16" aluminum on top of the stack with a strip of two wire lamp cord glued down the middle. If you use metal strips, make sure you round the top edges so they don't cut your bands under pressure.
Also make sure you do a dry run (or two) with the pressure strips to make sure you can pull them tight into all your curves.
Title: Re: pressure strip
Post by: kennym on March 28, 2017, 09:12:00 PM
I remember somebody using a pc of 12-3 romex for the center, said it worked good...