Making a template for RD riser.

[Buemaker]

I do not know if this is of any interest, but here goes.When forming the backside of the riserblock in order for it to fit your bowform including the laminates that go on the backside of a RD bow, I have found out the following: The contour of the riser block may fit your bowform perfectly, but once a quarter inch of laminates is stacked on the form the riserblock may not fit so perfect anymore, depending a bit on your form`s shape.So here is what I came up with: I shape the back of the riserblock on the spindle sander (the belly side is still in block form)so it fits the bowform perfectly or near so. Then I place the metalstrip, laminates and glassfiber on the form, the glass is placed on the top so I have a smooth surface showing. The riser is placed on top of the stack and clamped in place, if adjustments is necessary I mark it and fix it on the spindle sander or by hand sanding. Now the riser is actually good enough for gluing, but sometimes I tend to be a stickler for accuracy, so here is what I do. I cover the stacked laminates with Saran Wrap, put a good layer of Epoxy glue on the shaped riser and clamp it onto the stack. When the Epoxy has cured, the blank cleaned up and jointed and planed or sanded you have a very exact template that can be used on a pattern sander or for marking.If the combined thickness of your laminate stack is changed a bit it does not matter much or one could make a couple more templates. Works for me. Bue--.

[kennym]

Good idea!! That would save trouble in the long run of shaping risers!

[Buemaker]

Another thread bought this issue up so i'll bring this to the top. Bue--.

[kennym]

Still a great idea Bue!!

[kennym]

TTT

[Trux Turning]

Great tip- I fit my riser the same way with the glass and lams- never tried the glue trick yet.

[LC]

Intresting thread. I'm just getting started on building my first one piece bow. I've always made TD's in the past. So when you get a riser pattern to fit your form what exactly are you using as a pattern sander to follow the template?

[LC]

TTT I'm curious how most folks are making templates and following them with sanding machines. I can see doing it with pattern making router bits on bow forms but considering glue up on risers and such I'd think that is too smooth a finish. I've heard enough  negative reviews on the Robo sander that I'm hesitant on going that route.  So how do you do it?

[Walt Francis]

2X What Kenny said.  A great idea Blue.

[LC]

OK perfect way to make a EXACT template I agree. So how are you duplicating it?

[Bow-n-Head]

When using tapered lams between your riser & your form, you are "high centering" your rise& lams. This will cause gaps on the end of your riser when glued up.  I use parallel lams between the riser & form & put the tapers on the top. Make any sense?? Ray

[Crooked Stic]

another thing you can do if you have a drum sander is after you get your lam joined in the center is carefully run then thru and make the area over the riser almost paralell. You make a mark on each side where the ends of the riser will be. thickness sand untill you just start to remove the mark so not to get into the bendy part of the bow.

[Buemaker]

LC. Take a look at Crooked Stick`s setup in the other thread 1pc riser-fitting to form. Myself I did it a little different. I have a shaper with a 30 mm diameter spindle that revolves at 3000rpm. A little slower would have been better, but that is what I have. I had a machine shop turn a solid aluminum  roller with a 90 mm diameter and a 80 mm height that fits on the 30 mm spindle(actually I had them make two of them)I use water based contact glue to fasten 40 grit cloth backed sanding paper to the drum, use a short haired roller to apply the glue. The paper sticks in place even with such high revolutions. Below the drum on the spindle I place a bearing wheel with the same diameter as the drum. I bought the bearing wheel before i had the drum turned. This setup eats wood fast,fingers also so be carefull    When I have to change sandpaper I soak the drum with sandpaper in White Spirit or aceton.
A bit time consuming, but is OK. That is why I have two drums. Bue--.

[LC]

Thanks for the replies. It's all starting to make sense now. Like I said this is my first ever one piece and  sincerely appreciate the advice. I do have a drum sander and would have never thought of that "trick" Crooked Stic.

[Mad Max]

Quote bue"I cover the stacked laminates with Saran Wrap, put a good layer of Epoxy glue on the shaped riser and clamp it onto the stack."
I do the same but use 3/4" plywood so I have a pattern for the pattern sander