[Tillering Finished!!!] Well, here goes nothing! (First build)

[hobbyaccumulator]

Thanks for the advice OneBowonder.

Regarding tillering, do you have to take the bow off every time and clamp it down to take wood off? Do do most people just do it with the bow in hand/lap?

Also i think i'm going to do a pulley tillering setup since it seems not only easier to build but also more useful as you can see it bending from the distance. Can i just not put notches in the wood and simply have the rope+pulley hold the string in position at a certain distance down?

How long should my paracord be to tiller with? And how much bending in the bow do you need to start tillering? Right now my bow bends about an inch with the force of my arm (maybe 30-40 pounds? maybe less?); is that enough to begin the tillering process or should it bend more?

[loon]

Based on what I've read, I'd go straight to a very short brace after floor tillering.. the paracord will stretch anyway.

Do you want a string? If so PM me your address..

[Eric Krewson]

No, no, no, never go to brace after floor tillering if you are a newbie, you will probably hinge the heck out of one part of your limbs because you won't recognise the proper bend from floor tillering alone. On limb may be weak and one extra strong and you may over stress the weak limb, been there done that.

Spend some time on the long string adjusting the bend with your gizmo.

I don't recommend para cord for tillering but if that is all you have go with it, it is too stretchy. Make your tillering string as tight to the belly as you can and still get it on the bow.

If you make bows you have to make strings, not much to it and there are plenty of instructions out there. You could start by making a proper tillering string.

[hobbyaccumulator]

@loon I don't think brace is right for me yet, i definitely don't think it's ready at all i just know it bends a little bit. Plus i just bought a pulley to set up my tillering tree so i want to use it Thank you so much for the offer, i will PM you my address! I really appreciate how kind this community is to newbies, this community is definitely unique to most online communities i've joined.

@Eric Krewson
Thanks fort he advice, i agree i definitely want to tiller on the tree to see how it bends and get the real bow making experience.

When you say "tight to the belly" do you mean it should be parallel with the belly and up against it? Essentially the string should ideally be exactly the nock-to-nock length?

I was told earlier that paracord is an okay string to tiller with but not brace, so i got some since it was cheap. If i can't use it to tiller i can find some other uses for it (like the string to pull on for the pulley system). What's the difference between a tillering string and a real bow string used to shoot with? Is it just the length?

[Mo_coon-catcher]

The difference is the amount of stretch. Paracord stretches a lot, whereas a good bowstring essentially doesn't stretch at all. The string stretching will rob the energy that should be going to the arrow, in addition to adding shock and a very high possobility of wrist slap with every shot. Even with proper brace. That stretch also makes bracing more difficult since you will have to bend te limbs much further to allow for the string to stretch and settle at te proper brace height. That's why paracord, even though strong, isn't a good bowstring. Plus it's very thick for the same tensile strength.

Kyle

[hobbyaccumulator]

@Mo_coon-catcher thanks for the clarification. So i definitely would never want to use paracord for bowstring, but for tillering purposes it's somewhat okay - the difference being that it probably won't give you super accurate view of the bows curvature at each length since it stretches and lets go a bit. Thus if you pull the paracord out to 26" and look at the curvature, that might be the curvature of the bow at 24" with a real bowstring since the paracord is stretching to loosen the bow a bit.

What is a good idiot-proof guide to making bowstrings? both for tillering and shooting? I know it's made of B50 Dacron.

Also should i bother with attempting to make arrows as a first-timer? I feel like making arrows would require a lot more tools than making the bow. If I want the bow to be a 28" draw then do i need 28" arrows or even longer? Seems REALLY long for an arrow, but then again i don't have any intuition for what it should be since the last time i shot a bow i was 11 years old and it was a compound bow so probably doesn't have very similar arrows to a traditional wood bow.

[DC]

I like this one   https://www.youtube.com/watch?v=C07evRZT_PQ&feature=youtu.be

[hobbyaccumulator]

Also regarding arrow rests, am I supposed to cut into both the bow and riser? I feel like making a notch in the side of the bow for the arrow rest will make it less structurally stable in the handle and cause it to break.

[hobbyaccumulator]

 Been reading some more and I came across this Reddit user who made the same red board bow and his broke because he rough fed the belly and not the back. I'm confused what parts need to be rounded and which parts need to be flat.

Here is the Reddit thread with comments

[loon]

Would you want to do pin nocks? (Check PMs) because of the way I made this string...

I think the belly should be flat. Should a beginner 'trap' the back?

[hobbyaccumulator]

@loon, I think for my first bow I don't want to try pin nocks, also my tips might already be too narrow for pins unless I shorten the total length by just chopping off the tips of the limbs. I sent you a PM

I don't know what trapping means but when you say the belly should be flat does that imply the back should be rounded? How round should it be? Also why is one side flat and the other rounded? Why does this matter?

[Strichev]

My understanding is that when the wood is tension strong you can trap the back, making a smaller area of wood do more work - which is then not a problem as the wood is tension strong anyway.

Quite often the wood is rather strong in tension and somewhat weak in compression. Thus you want to maximize the area of wood that is the farthest from the neutral plane and undergoes the most compression - the belly. This prevents damage on the belly that results in set (or even worse - chrysals).

One obviously doesn't want to exceed the limiting parameters of the material. The stresses are greatest on the outermost fibers of the bow. That's why it's important to keep the back in one growth ring. A flat belly just increases the area on that the stresses (not sure about the correctness of the expressions I'm using, but I guess it convey the point) can then be distributed so that the cell walls don't collapse.


Probably all of this could be calculated in the confines of the bending a slender beam equation. However, with the nature of wood it's more of a guideline, but a doubtlessly helpful one at that, as it helps with understanding the principles of bow design.

As far as I know it's not obligatory to trap the back of the bow if you keep the belly flat. As a fellow beginner I'd suggest you leave the back alone (apart from the rounded edges) and keep the belly rather flat, thus making your bow's cross section akin to a rectangle. This helps with preventing set due to tillering errors that greatly compromise the  belly resulting is set and finally sluggish, disappointing bows.

In general, sharp edges are not good, getting edges down to a nice radius helps a lot. Gradual transitions are very important when (if) you decide to make a bow with a stiff handle. The fades need to be gradual, in a radius.

Edit: I might be overexplainining things

[hobbyaccumulator]

@strichev thanks so much for the explanation, i don't think i fully understand it but i get the gist.

Sam Harper's guide, then, seems innacurate as he clearly tells the reader to round the belly to get the cross section belly-rounded and back-flat. He doesn't even mention rounding the edges of the back side so right now my bow has sharp 90 degree back edges. Luckily I held off on rounding the belly, today i plan to do more work on the bow and hopefully get it on the tillering tree (which will just be a pulley connected to a 2x4 with a small piece of 2x4 as a ledge and pen marked inch points). I will keep this info in mind and round the belly and back very slightly (only getting a smooth transition instead of 90 degree edges).

[DC]

There should be no sharp edges. Round everything off to the radius of a pea. Sharp edges concentrate forces and a split or crack can start there. Sam may have rounded the belly a bit to take some load off the back. Rounding the belly has a similar function to trapping. If the wood is a little weak in tension(Red Oak may be, I've never used it) rounding the belly may relieve that a bit. Somebody please correct me if I'm out to lunch here.

[Strichev]

I'd like to add that if Sam Harper says that rounding the belly is better with red oak, then he's probably right. I was generalizing too much and somehow started thinking that you're making your bow out of ash or something. But the point is the same, it's just that oak might indeed be tension weak and a rounded belly is preferable. Never worked with it.

Hopefully I didn't do much harm by spreading half-truths.