For not in my bow do I trust, nor can my sword save me. But you have saved us from our foes and have put to shame those who hate us. – Psalm 44:6-7
Dominic Bender on Youtube issued a challenge he called, “The Challenge Tree.” The basic premise is that the woodworker would grab some log or live edge piece of wood which was not taller than the participant and such that they could carry it, and then make something with it. As far as challenges go, it seemed pretty simple to keep within the guidelines and spirt of it.
The last couple years we’ve been leasing out some of our property to a local farmer. And on that land there is a small stand of poplar tree which we affectionally call the “Quarter Acre Wood” a la Winnie The Pooh. The farmer cleared a couple of the smaller trees around the stand digging them up and pushing them into the others. I found one that seemed like it would be large enough to get the material I needed from and cut it down and moved it to the basement to thaw for the night.
It took some doing, but with a reciprocating saw, duct tape, and a couple more or less dangerous cuts I managed to get the root bundle off the tree. The log was then cut in half into about 3′ sections. I processed both on the jointer to create two square and flat edges. With one I ripped thin slats for the limb lamination and the other I ripped another parallel edge for the stave of the bow.
The profile of the stave was drawn onto one of the sides and the face was drawn onto the back. Then I used the bandsaw to rough out the profile saving the off cuts as I went. The off cuts were then taped back onto the log and it was turned 90º to cut the face of the stave on the bandsaw. The next step was to use rasps and files to do the basic shaping. The handle and arrow support was where most of the work was done and everything was just rounded over some. I then sanded the rough marks with some high grit sand paper and worked up through to 220 grit sand paper.
To do bent lamination I needed a form. I cut some scrap plywood down to equal sizes which would hold the laminations. The plywood sheets were then laminated up with glue and clamps. I traced the shape of a limb on the form and brought it over to the bandsaw. When the form was cut I took two passes, one along the top line and the second cut along the bottom line. This allowed the form to handle the thicker bottom of the limb. I then sanded the insides of the form and taped some padding on each side of the form.
The slats for the limbs were pretty rough when they came off the bandsaw. I used a block plane to take out the highest spots and bring them close to flat. The jack plane was used to create a smooth taper of 3mm to 1mm along the length of the slat. I mixed the epoxy and applied it to both sides of the slats for 3 slats. Once sandwiched together I pressed them into the form with clamps and tightened them down with additional clamps. After two days the forms were released and I drew the shape of the limb and brought it over to the bandsaw. A couple quick cuts and I had the basic rough shape of the limb. Two were clamped together and a block plane was used to bring them both to the same shape. I then sanded the limbs remove any sharp edges and make them flex more evenly, so as to not twist.
I used a forstner bit to make a smooth spot for the flange nut, which would be used to secure the limbs on the stave. I had to then widen the first 3/8″ with another drill bit for the barrel of the flange nut. Next the hole was bored for the shaft of the of the bolt which would hole the limb. The final part of the operation was to duct tape the limb in place while drilling the holes through the limb.
I attached each limb separately one at a time. One issue became apparent with the flange nut and bolt I was using. The nut would keep spinning, despite the tightness around of the nut in the wood and I planned in the future I would epoxy that in place to keep it from spinning. However, when I was testing the limb for flex I found another fatal flaw. The limb just snapped beyond a point. Investigation found that it was along a knot in one of the plys in the limb. I used the last remaining slat that I had, which had originally been rejected, to attempt a replacement limb. The replacement limb suffered the same fate as the original.
Lessons learned: poplar is far too weak of a wood to use for bow limbs. Knots are incredibly weak compared to straight grain.