I Beams in TD risers

[Bryan Adolphe]

Iam just cutting up some walnut for my first take down riser, and my question is when installing an I-beam from back to belly if I centre it should it be wide enough to except the limb bolt insert 1/2”+ , I was planning on using 3/8 “ hard maple on this one just because its my first go at it and it may get  this will be a long bow riser, so it will be an inch and a half wide.

My other question is, is there a way to strengthen a riser by plunge cutting into the back of the riser either with the tablesaw or a router and installing say G 10 or a hardwood then put overlays over top ? I welcome your ideas. Thanks guys. Bryan

[Kirkll]

You can go from 1/4" to 3/8" I-beam thickness no problem & rock hard maple will make a good stiff I beam for walnut. Bloodwood is another great I-beam material

As far as using a plunge router and inserting a G-10 tendon in the riser..... Well.... I suppose it would work for stiffening things up, but you still need to consider the compression forces on the belly side of the shelf. I'm not certain how that would work using walnut. 

 I did something similar a couple times and used lead to add mass weight to a long bow riser, but i did it on the belly side ramps and covered it with an overlay. I just drilled holes and used buck shot pellets and silicone. The lead shot suspended in the silicone acted as a vibration/hand shock dampener too. But.... the hand shock portion of these bows are better regulated with string tension or preload at brace, than mass weight.

G-10 is great stuff and i use it a lot in risers. You cant beat the strength.... But.... There is a down side to using this stuff.  The moisture content in your wood needs to be bone dry when laying it up with G-10. Many times i've used G-10 I beams and sent them to dry climates, only to have wood shrinkage issues, and have slight separation on the glue lines resulting in me having to refinish the riser.....

The secret to success using this stuff is laying up the riser, and getting it shaped and sanded, then put it in your spray booth or hot box at about 90 degrees over night. If that wood is going to shrink, it will do so before finishing, and can be filled with super glue and sawdust prior to finishing.  I have a real Love/Hate thing going on with G-10, but i continue to use it.

Realistically...For trouble free bow building you would be better off sticking to all wood for riser accents, I-beams, and footings.     .03 cents worth.    Kirk

[Crooked Stic]

I know there are a couple of top end guys that slot out the front of the risers and use G10 but am not sure of how to do it properly. .But like Kirk said using G10  your wood needs to be very dry. I use wood to wood  mostly. If I use G10  say in a two piece whatever wood I use usually is stabilized.

[Stagmitis]

Good point with the stabilized wood crooked! I might break down this year and get a pump and some juice 

[Longcruise]

I think Big Jim does some of those in solid G10.

[Crooked Stic]

You might be able to buy the stabilized wood already done cheaper than getting a pump juice and everything it takes to get setup. In the past I could get about 3 riser size blocks of maple out of a gallon of juice.

[Nicholi]

Stic,

Do you have a source for stabilized blocks? Most places I look are usually out of stock, or only really do knife scales.

[Crooked Stic]

Big Jim's should have some ready to use.