I have the binghams plans for the 68" pronounced takedown longbow. It has a template for a 17" riser. What happens if I use the same length limbs and make the riser 15". Will the poundage go up?
Also without a joiner how do I square up a riser block and make sure the fades are perfectly flat?
Thanks
Terry
Your bow will come out about 7# lighter than the target weight if you shorten the riser two inches, maybe more. It will not go up in weight. If you add length to the riser it should go up in weight by around 3.5# per inch.
I use a 4 x 36 belt sander and a steady hand to square up a riser block. My riser blocks are close to square on at least two sides before I start though by using 8/4 lumber stock.
Just to be clear my bow would now be 66" long,
still the same answer? I would loose about 7#s
IMO the draw weight will increase a bit, but not very much. The length of the working part of the limbs is still the same, but the string angle will be steeper. This will cause a higher increase of the draw weight towards to end of the draw.
----------
Andy
Without a jointer, I sometimes use a sheet of sandpaper on a flat surface (e.g. glass or your tablesaw) and sand the intended surface flat. This is how I treated my limb pad angle cuts on the last couple T/D's I made.
OK, I thought you were building a 68" bow. I didn't pay attention to your details. I think Swissbow has it right for shortening the bow. Two inches is very small change that you may not notice. What are you trying to accomplish with the change? Just a shorter bow?