I am seeing things in your tiller that need to be addressed before you go further than brace height.
You need to make a tillering gizmo and straighten out the flat places in your limbs.
I had a how to make one and use it tutorial to here but got banned one time and it was deleted. I have another over at the primitive archer site in the how to section that is still up.
Pretty simple, a 6" block of wood with a 5/16 hole drilled in the middle and a 1/2" hole drilled halfway through the block on top of the 5/16" hole. Knock a 5/16 nut down in the bottom of the 1/2" hole and screw a pencil in the nut.
Lets see if this works for a copy and paste the pictures probably won't be there.
USING THE TILLERING GIZMO
After floor tillering your bow, bend the bow slightly on your tillering tree or tillering stick, I start at about 3” of bend using the long string. Retract the pencil in the Gizmo and run the wood block up the bow’s belly and find the widest gap. Screw the pencil in the block to a point it is almost touching the bow’s belly at the point where you found the widest gap. It is best to start with a little wider gap between the pencil and limb than what is shown in the picture or you may mark the whole limb instead of just the highest spots. I change the angle the pencil has been sharpened to a very short angle and sand the tip of the pencil flat for the best results in marking the limb. This lets you work very slight bends.
Run the Gizmo up the belly making sure it is centered on the limb. The
pencil will mark non bending areas that need wood removed. Start on the long string; continue at brace and up to about 20” of draw. You do need to have a way to hold your bow string while you mark the limbs with the Gizmo.
I have holes in my tillering tree and insert a 3” piece of dowel in one of the holes to hold the string with the limbs slightly bent while I mark the limbs with the gizmo.
Go slow, no more than ten scrapes on the marked areas of the limb, flex the limb 30 times and recheck. My bow limbs tend to be slightly round belly so the Gizmo only marks the top of the crown on the limbs belly. I scrape the marked area as well as the rest of the limb side to side to keep things even. You can get the limb bending perfectly this way. You will still have to eyeball bending in the fades but the rest of the limb will be perfectly tillered, hinges will be a thing of the past.
I adjust the gizmo one time on the long string and set it to the deepest bend on the weakest limb. I use this setting for both limbs. If you continually adjust the gizmo you will chase weak spots up and down your limb. One adjustment and hold this adjustment until you have removed enough wood to the point that can run the gizmo up both limbs without making a mark. As you increase draw length readjust the gizmo.
Make a few passes with the gizmo on your limb and the areas that need attention will be perfectly obvious. You can fine tune the tillering by closing the gap between the pencil and limb to almost nothing. At this point I like to use a cheap orbital sander to remove both wood and any tool marks that are left. With course sand paper, the sander will leave tiny swirls in the wood so I like 220 grit for my final tillering work and follow with a light hand sanding.
The gizmo doesn’t work in the fade out area of the riser so you will have to eyeball the bend in this area or put a flat board across the back of the bow in your tillering tree and watch the gap between the back of the bow and the board to see where the limb is bending.
Tillering that once took me hours to get close takes me about 45 minutes with the Gizmo and the end result is close to perfect.
Remember the key thing to proper tillering is using a scraper or sand paper for SLOW wood removal, no rasps or belt sanders.
Here is Roy's;
Topic: Selfbow build along. (Read 6095 times)
