Riser question

[mzombek]

I am in the process of making my first D/R longbow and need help on dry run on my form.
When making my riser, I cannot get a perfect curve so when I lay it on my fiberglass and lams, there are gaps between. Is what I tried to do is place tape on my form so it takes up the gap between the lams and fiberglass.
Is this acceptable?
Thanks,
Z

[kennym]

That will depend on how picky you are. Is the form a perfect curve? If so, I run the outside of riser on a disc sander in long gentle swipes, you can get a very even curve doing this.

Otherwise you just have to fit it to the form.

If you shim with tape, you will most likely be able to see it wiggle, especially if you know its there.

Some guys put a piece of rubber on the form to help squeeze it all together. Dry run with that too if you try it....

[Buemaker]

Perhaps something for you here.
 http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=125;t=007584#000000

[jsweka]

Part of the reason why I prefer my Hill style bows with a straight riser over my r/d bows is this very issue.  It can be frustrating getting it to perfectly match.

[Mad Max]

I do the same thing with half the Stack but I use my Riser Template
On this build I did a footed riser.
I clamped my templates together with the stripe and buttered up both templates with smooth on


   

[Bvas]

The above is good advice and a great idea. But if you don't have a pattern sander or a template bit for a router here is my advice.
With your riser on the form, mark and sand the humps and bumps that are lowest near center on the riser first. Then work your way up and out on the riser towards the fades.  And always use a long sanding block. Sanding freehand or with a short block can result in making the dips deeper.

[Wagstaff]

I guess it depends on how much you like the curve you built into the riser section of your form..  

Here's another thing you might try..  If you slice your riser into .100-.125" pieces, you can glue, stack, and bend them, so the back of your riser will precisely to fit the form.  

Pictures might help..

Start with the sliced Riser pieces..

 

Re-assemble them with epoxy. inside your pressurized form.

 

After removal, the back of the riser is an exact fit to your form.

 

Work on the fades on the belly side only..!

 

Makes a nice bow.. Just another approach.

 

[die_dunkelheit]

Jeff what wood is that in your first pic?

[Mad Max]

Nice way to go Jeff

[Roy from Pa]

Very nice, Jeff..

[goobersan]

Great tips Bue & Jeff ! Using both methods you would get more risers with less wasted wood