This morning I took the bow out of the oven and unwrapped it. It felt just like Christmas. The next step is to rough it out, clean it up, and get it ready to tiller.
Roughing, cleaning, and preparing for tiller
Here's a before and after shot from the time I took it out of the oven until I had it all cleaned up.
Cleaning it up involves cutting it out with the band saw and then using the belt sander to sand the sides until there's no more tool marks or glue. Don't worry so much about the handle since you're going to wait until the end to give it its final shape anyway.
I also radius all four corners on the limbs. Having rounded corners reduces the chances of lifting a splinter or anything like that.
Whenever I do a bamboo bow, there's always one node on the back of the handle that is not centered. I always make the end with the node the top limb, so I cut the arrow rest accordingly.
Usually, when I cut an arrow rest, I don't measure a certain distance from the center. I just hold the bow in my hand like I'm going to shoot it and mark with a pencil where I want the rest. But since I'm doing a build along, I decided to measure and put the arrow rest 1.25" above center.
I cut the fades 3 inches from the ends of the handle with the band saw and then rounded them out and got them closer to the limb with the elbow of the belt sander.
See how I still have some glue on the belly of the bow just after the fades? That's because I like to leave that area alone for now. It allows me to work on the fades later without causing a hinge.
To radius my arrow shelf, I use my disk sander. It comes with a plastic cover over it that gets in the way. I cut part of the cover off with a dremel tool so I can get the bow on there.
Having a radiused shelf reduces drag on the arrow by limiting contact. Notice how there's no sanding belt on the belt sander. That's to protect me while I radius the shelf.
Next, I cut the nocks. First, I round out the tip overlays and grind the tip fades with the belt sander. Then I start cutting the nock one inch from the end. I actually measure this, because you can't make a string for a bow if you don't know exactly how long it is. I start the cut with a triangle file because if I use a rattail file without first having a little groove, it will slip and slide all over the place, and I can't cut accurately. So first I make a groove with the triangle file. Then I start cutting with the rattail file.
Everybody has their own way of getting even nocks. I used to do all kinds of intricate measurements, but I came up with an easier way that seems to work pretty well. After I cut that initial groove in the tip overlay, I round it over and cut at an angle on one side. Once I get it cut, I round it toward the belly, too. Then when I flip it over, I can see both the groove on the back and the groove on the belly from the other side at the same time.
Isn't that cool? Now it's easy to cut the new groove to match the one on the other side because I can see it while I'm filing. Here's the result:
I don't cut these grooves too deep because I may need to adjust them later to get the tips aligned. I just cut them deep enough to hold a string.
The only thing left to do before I start tillering is to prepare the back. I used to put masking tape on the bamboo before glue up to keep the glue off the back, but that turned out to be unnecessary. It made it hard to cut the bow out because I couldn't see a clear line between the bamboo and the wood. Besides, the glue that gets on the bamboo isn't much of a problem. If there are big chucks, it's easy to pry them off with a pocket knife. Everything else can be sanded or scraped off with the rind.
I used to leave the rind on and just sand it smooth. One time, I lifted a splinter that was only rind deep, and I've been sanding the rind off ever since. I think most people scrape the rind off, but I use this handy dandy pneumatic drum sander.
It's got a 1 HP motor and an inflatable sanding drum. I love that thing. It's a good tool to tiller fiberglass bows with, too. Since it's inflatable, you can easily sand the rounded surface on the back of the bamboo. I first sand between the nodes leaving a little bit of rind around the nodes. Then I make a few quick passes over nodes so as to get the sharp edge off but not sand them down too much.
Once I've got the rind off, I want to get the back of the bow as smooth as an android's butt. I do that with 100, 150, 250, 400, and 1000 grit sand paper. After the 1000 grit, it's pretty smooth. Having a smooth surface like that reduces any chance of lifting a splinter. I couldn't find 1000 grit at Home Depot or anything like that, so I got it at an auto parts store.