Johan... I hope this will help... I'm pasting in a couple of pictures of my set up:
Here's a shot of the latest backing plate I made, this was for a forward riser Hill style bow I just finished. Normally, my backing plates are in two pieces, since the riser separates the limbs and laminations. In this case, the laminations were all forward of the riser so I built the bow with full length lams and used this backing plate.
Here's a close up of the layers: masonite, mud flap rubber, 1/8" aluminum
Obviously, I use metal clamps while you plan on rubber bands, but here is a shot of the layup
Be sure to use plastic sheet between the form and the laminations, and again between the laminations and the backing plate. It will save you a lot of clean up and prolong the life of your form. I have two forms made of aluminum and wood. I have taken 23 bows off of them and they are like new!
If I can be of further help to you, email me direct at:
[email protected]