Trad Gang

Main Boards => The Bowyer's Bench => Topic started by: Mad Max on August 03, 2022, 05:10:49 PM

Title: Warped form
Post by: Mad Max on August 03, 2022, 05:10:49 PM
How do you straighten your form?

This is a 64" R/D form 1 piece.
I have used 3/16" and 1/4" thick angle iron but sometimes it takes 1 on each side.

Holding a straight edge to the form there was a gap about 3/16" in the middle.
I needed a 3rd hand, picture did not turn out good.

(https://i.imgur.com/e80mCiG.jpg)

Sometimes I use 1" x 3/16" flat bar, drill three 1/4" holes, one on each end and one in the middle.
Tighten the outside ones flat to the form, All thread with a nut on the inside and screw it out until flat, 2nd nut to lock it down.
Very little tension on this one, I turned the all thread by hand. :thumbsup:

(https://i.imgur.com/9TqJxlX.jpg)
Title: Re: Warped form
Post by: mmattockx on August 04, 2022, 10:23:46 AM
Now that's a problem. Is it flexible enough that you can force it back straight and then fasten another layer of plywood or a steel angle to brace it in that position? Maybe even a piece of plywood on each side to significantly increase the thickness after being put straight?


Mark
Title: Re: Warped form
Post by: Stagmitis on August 04, 2022, 05:38:56 PM
Curious what material the form is made of.
Title: Re: Warped form
Post by: Mad Max on August 04, 2022, 06:17:36 PM
Now that's a problem. Is it flexible enough that you can force it back straight and then fasten another layer of plywood or a steel angle to brace it in that position? Maybe even a piece of plywood on each side to significantly increase the thickness after being put straight?


Mark

Plywood is high $, the form is made with 7 ply. plywood, If I push on it with the screw past flat and leave it like that after a few months it may become straight, I did that on a different one and it worked.
Title: Re: Warped form
Post by: Roy from Pa on August 05, 2022, 07:30:11 AM
The form isn't the only thing in your shop that's warped:)

 :laughing: :wavey:

Title: Re: Warped form
Post by: Mad Max on August 05, 2022, 07:42:35 AM
Form isn't the only thing in your shop that's warped:)

 :laughing: :wavey:

It's me It's me Ernest T :laughing:
Title: Re: Warped form
Post by: Buggs on August 05, 2022, 08:51:27 AM
Have you thought about glueing it up while clamped to a flat, level surface and sealing it with bar top epoxy.

You must live in a humid climate?
Title: Re: Warped form
Post by: Mad Max on August 05, 2022, 09:27:49 AM
Have you thought about glueing it up while clamped to a flat, level surface and sealing it with bar top epoxy.

You must live in a humid climate?

Yes It was flat years ago, I have a dehumidifier running for years and it sat on a rack for years also, I make Recurve mostly
Title: Re: Warped form
Post by: Kirkll on August 11, 2022, 10:42:33 PM
I'm not sure whether it will work on your plywood or not, but i have sanded the wood to raw wood both sides and wet down the crown side and put weights on it. it may take a few days in warm weather, but it should come back with moisture introduced. You are basically warping it back to straight again.

 i've fixed many warped doors using this technique and solid wood planks too.  With your form, once you get it straight again, edge band it with oak or even use the flat iron, or angle iron. Then seal it really well.     Kirk
Title: Re: Warped form
Post by: Mad Max on August 12, 2022, 07:43:44 AM
I finished the bow Yesterday with the form, I have several that I did this way. :bigsmyl:
That one I have not used in a while.
Title: Re: Warped form
Post by: Mad Max on August 12, 2022, 08:09:47 AM
I'm not sure whether it will work on your plywood or not, but i have sanded the wood to raw wood both sides and wet down the crown side and put weights on it. it may take a few days in warm weather, but it should come back with moisture introduced. You are basically warping it back to straight again.

 i've fixed many warped doors using this technique and solid wood planks too.  With your form, once you get it straight again, edge band it with oak or even use the flat iron, or angle iron. Then seal it really well.     Kirk

We use to pour water under cupped stacked 1 x 6 yellow pine back in the day :thumbsup:
Title: Re: Warped form
Post by: Kirkll on August 12, 2022, 09:39:19 AM
You can excellerate the process using a wet cloth and an iron too. Steam infused…

The slightly bent forms are not a big deal. It’s the twisted ones that will give you the blues….   Kirk
Title: Re: Warped form
Post by: Mad Max on August 12, 2022, 11:09:29 AM
Yep