Feedback on Box and Form

[Trad Dad]

I would like to get some feedback on the Box and Form I'm making. Mostly the Form since the Box is half built.  

Here are some renderings and a drawing.
 http://www.shemah.net/bowForm1.jpg
 http://www.shemah.net/bowForm2.jpg
 http://www.shemah.net/bowForm3.jpg

When I finish, I'll post some photos.
Thanks,

[Roy from Pa]

Nice, but I would make the difference between the center post and mid limb posts one inch, instead of 1/2. My center post is 3 3/4, mid limb posts are 2 3/4 and end posts are 6 inches. The box specs are perfect.

[Trad Dad]

Thanks Roy. I thought it looked a little shallow but wasn't sure. Here are a couple of updated images.

 http://www.shemah.net/bowForm1a.jpg
 http://www.shemah.net/bowForm3a.jpg

[Roy from Pa]

Much better I think.

[macbow]

If your going to use a 2x4 for the base you could add a couple of pieces of 1/4 plywood on each side of the posts to help them stay in place.

If going for 50 pound plus bows might need to double up on the 2x4 base.
I think Roy has steel in his.

[Trad Dad]

Thanks macbow. I noticed the steel in Roy's and was wondering if I would need to do that.

On the plywood, do you mean pieces that would extend down on each side of the base?

[Roy from Pa]

My form base is 1 inch thick Oak plus 1 inch steel angles on both long sides. You exert a lot of force clamping bows into r/d, so you don't want your form flexing causing you to lose reflex. Plus the angle iron gives me a little lip along both sides keeping my blocks snug in place. Also on the very ends of the form I have a little block of wood glued down, this keeps the end blocks from sliding out, because the force of the bow bending down exerts pressure outwards and will push the end block sometimes. Click on the picture below, it's a video.
   

[macbow]

Yes  that is what I meant with the plywood.
Mine started,with just a 2x4 and it flexed too much.
I then added  a 2x6 with some notches cut where 3 clamps will fit.

[Trad Dad]

Thanks for the info guys.

Roy, that video really helps.

macbow, I have the base as a 2x6 with a couple of strips of wood down each side.

These images show all the changes.
 http://www.shemah.net/bowForm1b.jpg
 http://www.shemah.net/bowForm2b.jpg
 http://www.shemah.net/bowForm3b.jpg

[Tom Leemans]

Q: How many PBR's does it take to build a bow?
A: All of them

The great thing about this type of form is that you can exchange the center support to build a straight reflex bow. I'm gonna make recurve end supports for mine. My next BBO will be a R/D recurve!