Tillering on Warbows?

[D. Tiller]

Well, I've done a couple now but hope I'm not doing it wrong. Maybe you all can tell me if I'm doing it right. I first start by getting the tips to bend untill I can get the bow to a braced height then start pulling it back further and taking wood off the inner limbs till it comes full compass at its draw length. Is this how you all do it? If not how do you tiller your bows?

David T

[Marc St Louis]

Just the opposite for me David. Tips come last

[D. Tiller]

hmm! I would think that would make the bow whip tillered. Or am I wrong? Maybe I should just be more conserned on eavenning up the bend at the beginning and worrying about the tiller as I go?

[alanesq]

I have only made 3 bows so not really qualified to post
but anyway ;-)

I tend to leave the last 10" stiff and forget about that (until the very end anyway)
and concentrate on just getting the rest of the bow to bend even if only by a very slight amount (i.e. no completely stiff areas)
i.e. pull it on the tiller, look for any area which doesnt seem to be bending then remove a bit of wood from that area and repeat
the mid section tends to always be totally stiff to start with
once it is starting to bend along the entire length then its just fine tuning to get the tiller as you want it

I find it tends to bend too much around 1/3 in from the tips mostly, so keep that bit on the stiff side to start with


Keep a very close eye out for any sign of a hinge - I suspect most broken bows on the tiller are caused by carrying on when there is one as its very tempting

[D. Tiller]

Thanks Alan! I was under the impresion that the warbows where first tillered out at the end untill they ended up at brace height and then as you pulled the string back they where tillerd to bring it full compass. I will try it your way and see how it goes!

David T

[alanesq]

I am completely self taught so its quiet possible this is the correct technique ?
but this is how I did mine and it seemed to work well for me

I tend to keep the tips pretty stiff (probably mainly because I am scared they will snap off)
but if they are on the stiff side you can always claim its done on purpose to prevent the bow stacking ;-)

[markinengland]

On the "warbows" I have made I have aimed for a completely even bend and I like to get it even e arly one and keep it even to avoid getting localised set. I think this gets about the maximum performance per weight/length and it's easy! My feel is that this may have been the approach taken by bowyers of old. If it is easy and repeatable and make sense from a "comercial production" point of view it may have been used for mass producing warbows. This perhaps explaines why Ascham talked about whip tillering a bow once shot in. Obviously bowyer hadn't.
Anyway, I like to tiller the bow to an absolutely even bend at brace height, perhaps leaving the handle slightly stiff. Once the bend is even at brace height the bow can be worked back, keeping the bend even (still checked at brace height) and working to draw weight. Working the bow back at say 20 to 50 pulls per inch, keeping the bend even, avoiding weak and strong spots, pulling after every wood removal with scraper and file, keeping the bow basically looking like a finished bow ready for final sanding gives me the weight I want, the bend I want and minimal set. If the bow is just slightly too powerfull taking the bend a little more into the handle can make it easier to pull and drop the weight just that little bit without re-touching the imbs themselves.
On a laminated bow I basically pre-tiller the belly which makes life a lot easier later on. I avoid long string tillering as it can really throw you off. Get it cut out and shaped right, get it just about evenly bending floor tillering and get it to a slightly low brace height and even bend as soon as possible seems to work for me.
One thing I did find out today is that diamond honing paste on a leather as used for fine sharpening blades works a real treat on getting a mirror finish on horn and well as finely sanded Ipe.
Mark in England

[D. Tiller]

Thanks Mark! I have been doing that in the past too. Seems to work right. I will try the paste too!

David T

[Marc St Louis]

David
I can't see how you can tiller the tips first. Doing it that way would stress the tips more than necessary since they only do a very small amount of bending compared to the rest of the limb. The widest part of a limb is the part that can take the most bending without taking any set. That is why it should be that part of the bow that should be tillered to bend evenly first.

[D. Tiller]

Thanks Mark! That should save me from snapping some limbs!!!

[adb]

Hi,
In my opinion, if you tiller the tips first, your bow ends up whip tillered, and your set will be exaggerated. Leave the last 8 or so inches alone until the end, if at all. Get it bending evenly in the middle first, full compass for a proper warbow.

[D. Tiller]

Been working on it this evenning. Got it to brace height  and the bloody thing just about hinged on me in the lower limb.  Turns out there was a tiny pin knot just where it hinged. Got it evened out and think I may still reach my #45 draw weight at arround 27". It's a lighter bow in the Warbow design since it is for my mother who showed and interrest in the bows I  was building. May have to lighten it up a bit more for her though.

David T

[sagitarius boemoru]

I have only made couple of hundreds and not that much warbows. Though - with any bow it is beneficial to tiler tips in the end. Its the area where smallest loss of material does greatest difference. Also with warbow it is beneficial to keep the middle tad stiff for what it takes and scrap it also in the end since this is easy to overdo and end up with a bow which just bends too much through handle.

What I find nice about MR pattern is that it gives you good idea how the bow was layd out initially and what sucession of steps it took to make it.
For example - the tips were initially layd out wide  to get enough wood in midlimb to achieve heavy weight. That is also benefitial for you have enough tip thickness for cutting tilering nocks in.
Then once you approach the moment you need to put the nocks on, you narrow the last portion of the limb (say the tip), which can be done without loss of stifness.
They can be tilered all the way down and the nocks put on in the end, but I find beneficial to have the nock on the moment I want to string it, since there is still enough time and material for correction of any mischief.

Its not that difficult to make big honking bow, but to make one which will perform well for its parameters and also looks well in the terms of proportions is much more difficult.
And to do it with any other material than high quality yew for this particular pattern is entirelly different story. (No wonder when the pattern is intended for yew)

Jaro

[markinengland]

Jaro,
I think that many people have different methods to make bows and what works for one person may not work for another.
I think whether you use a long string or even an initla low brace height for initial tillering makes a big difference in this as it really does influence the tips.
Mark.

[D. Tiller]

Got the hing out guys and finnished tillering the bow in. Unfortunatly it took a bit of set in the lower limb and just a tad in the upper. Think the hing overstressed the wood a bit. But, it does shoot well for its draw weight so I'm prety happy with it.

Unfotunatly, my mother will not shoot it until I put and arrow shelf on the bow and a leather wrapped handle. Real bummer since I dont often like putting anything on a bow of this design. Just cant seem to get her to shoot off her index finger for some reason.

Now I will be starting on the heavybow in the 80-90# range. Just need to glue up the stave and start carving away at it. I think one of the problems with set is that I have been using yellowheart as a center lamb. Pretty weak wood if you ask me, I think I will stay away from it on the next bows I build.

David T