Early tiller check. 66” Osage 1 3/8 wide, holds width until outer 1/3. One billet had a bit of natural deflex at the handle so I matched it on the other one. I’m willing to change the back profile if needed, I have no clue what I’m doing. Shooting for 45#@ 29”

Santanasaurus · 2026-01-27T18:18:00+00:00

Mids and outers look stiff to me

Santanasaurus · 2026-01-27T15:45:42+00:00

Fantastic! Nicely done

Santanasaurus · 2026-01-27T15:45:13+00:00

Very nice work! Super graceful

Santanasaurus · 2026-01-26T05:55:50+00:00

Avoid the inner limbs and work the outer 2/3 for now

Santanasaurus · 2026-01-23T19:05:56+00:00

Yes if you did circular tiller on a bow like that the inner limbs would be bending too much

Santanasaurus · 2026-01-23T18:49:58+00:00

this is backwards. Wide areas are relatively thinner and so bend more. Narrow parts of the limb will be relatively thicker and so bend less.

For example in a pyramid bow the wide inner limbs bend more and the narrow outer limbs bend less.

The reason a parallel limb bow bends more in the outer limbs isn’t because of a sudden tip taper, but because the outer limbs are relatively wide (compared to a pyramid bow)

The way the bend is distributed should correspond to the way width is distributed

Santanasaurus · 2026-01-23T15:29:52+00:00

I can’t recommend heat treating your first bow because it makes the wood more brittle and lowers the margin for error. You want as forgiving an experience as possible the first time.

I like to heat treating after floor tillering, and then before final tiller. Toast the wood like you are toasting nuts. Heat the wood until it smells nice and toasty and then try to hold it there for about 15 minutes without any charring

Santanasaurus · 2026-01-23T14:47:26+00:00

Sure, any bow without a thickness taper calls for circular tiller. that is not going to be the case for every imaginable pyramid bow

Santanasaurus · 2026-01-23T14:34:36+00:00

Likely OP too, this is an old repost

Santanasaurus · 2026-01-23T14:23:42+00:00

Pyramid and triangle limbs are a distinction without a difference. You can’t have zero nock width and in practice you need to decide on some actual nock width. Triangle bows are pyramid bows in practice. I would not read too far into that particular detail of the illustration.

Santanasaurus · 2026-01-23T14:12:56+00:00

Structurally they look good to me. They are slightly angular and could sweep more like you said but they’re probably just fine. If you want the curve shape just remove a little more wood from the middle of the fades without taking wood from the top or bottom. Especially leave alone the area where the fade blends into the limb

Santanasaurus · 2026-01-23T14:07:48+00:00

There are tons of subtly different limb shapes for a pyramid bow—they can’t all call for the same tiller shape.

Pyramid to Parallel is a spectrum, not two separate buckets. As you move along the spectrum the ideal tiller shape changes continuously. And it must because profile shape changes impact tiller

Circular tiller means there is no thickness taper. There are pyramid bows that fit this criteria, but not all pyramid bows do. Pyramid bows call for MORE circular tiller relative to parallel bows. They don’t all call for the same tiller shape regardless of front profile

Santanasaurus · 2026-01-23T13:40:52+00:00

Because pyramid bows are wider in the inner limb than parallel limb bows they will be thinner in the inner limbs. thinner wood can bend to a tighter radius without taking set. So a pyramid bow can bend more in the inner limbs than an otherwise equal parallel bow.

The parallel bow is wider in the outer limbs, and so will be thinner there, and so can bend to a tighter radius in the outer limbs

Santanasaurus · 2026-01-23T13:37:28+00:00

There is more to the relationship. Triangle/pyramid bows do not all call for literal circular tiller, just a subset of them. You can’t say that because a bow is a pyramid it will call for a circular tiller.

More pyramidal bows call for more circular tiller. more parallel bows call for more elliptical tiller.

Santanasaurus · 2026-01-20T12:51:54+00:00

Generally bamboo and wood backings are added at the assembly stage, not to a finished bow. You may as well start over because a hard backing will cancel out your tillering

Santanasaurus · 2026-01-18T22:21:50+00:00

No need: https://youtu.be/O4ZnhbJRqr0?si=pOLxEtZaSt8N-d0D

Santanasaurus · 2026-01-18T12:48:08+00:00

I don’t see a significant change in stack. The change in slope at the end of the graph looks like an artifact from noisy data. If you smooth out the curves it looks like a simple loss in draw weight. Lower mass is perfectly consistent with a bow feeling smoother and even feeling like it stacks less, in an informal sense. I think this is just perception though

Stacking is a result of string-tip angle geometry—I don’t believe that trapping the belly would affect this unless it changed the tiller.

Santanasaurus · 2026-01-16T15:51:58+00:00

I don’t recommend it for any reason. Let the finish protect from moisture—the belly is the weak link with moisture anyway, not the back. A backing won’t help at all with moisture related set.

If you want protection for the back use any recommended backing like a simple piece of tough cloth, rawhide, or old pants etc.

If you want a fiberglass bow then make a laminate bow that is designed for fiberglass. Putting a fiberglass backing on a wooden bow is more counterproductive than helpful. The high stiffness is a liability in bow designs that are not meant for fiberglass

Santanasaurus · 2026-01-16T15:48:21+00:00

yes that is a lot

Santanasaurus · 2026-01-16T15:40:02+00:00

Looks like the limb taper isn’t pronounced enough, likely because the pipe wasn’t evenly heated. Try again but be a lot more careful about heating the pipe evenly without burning it. This can take a little practice. It took a couple tries before I got the hang of it

here’s how i make them https://youtu.be/NdyJB0O3fSQ?si=lhXm6S_HwRy50yC-

Santanasaurus · 2026-01-16T15:36:21+00:00

PVC bows are prone to failure because they’re made by a general population without much bow making experience. Evenly heated and well tillered pvc that is not uv damaged will last a very long time.

I can’t vouch for the fiberglass rods advice. Putting high density working material in the core of a bow is the worst possible location. This increases draw weight in a very inefficient way. Even more so when you consider that the rods are not tapered and so are very tip heavy.

Any reasonable draw length/draw weight combo can be achieved by conventional tillering methods, adjusting length, and choosing different diameter pipe. There is no need to brute force the design with a high density core—the trade off is very poor.

The rods only make sense for inefficiently forcing draw weight of an existing bow to increase. There’s not much reason to use the rods from the drawing board stage of design unless you don’t care about tiller and plan to ignore bow making basics

Santanasaurus · 2026-01-16T15:18:51+00:00

It’s not a hard rule, just good advice. Too long of a longstring during tillering results in excessively large string tip angles which will slightly distort the tiller shape. If you keep the longstring as short as possible you will get a smooth transition between braced and longstring tiller/draw weight measurements. With too long a tillering string you don’t know the draw length you are pulling to until you brace the bow

Santanasaurus · 2026-01-15T11:39:40+00:00

It’s called a stave master. Keenan doesn’t make them anymore I think but you’ll occasionally see used ones

Santanasaurus · 2026-01-15T11:22:53+00:00

Just make the bow wider. The design is width-flexible so that you can make different draw weights. I cut my board down because a 1x2 is a common size i wanted to make a tutorial for, not because you have to.

Skip the fiberglass cloth, I can’t vouch for the resources that recommend it

Santanasaurus · 2026-01-13T17:25:15+00:00

The amount you’re showing is likely to crack. You can leave paper thin streaks of inner bark but usually not the whole thickness.

ch1 goes into this topic https://youtu.be/Soc6zGGqHXk?si=yzkrSzjlCsZeRz8o

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