First attempt at tillering

PLEASE HELP TO FUND ARCHERY INTERCHANGE

osprey

Member
This is my first attempt at tillering. The bow is Ash/Greenheart/Ash laminate.

It has ended up about 38lbs at 28". I think I've managed to get the whole limb beyond the handle to bend, but leaving slightly stiff tips, which I've read are a good thing. What does it look like to experts? Anything needing adjustment? or does it look about right to start finishing?

bow28inch2.jpg
 

Del the Cat

Well-known member
Pretty good, :) (Sorry I've been slow responding, only just seen it!)
slightly stiff on the inner 1/3 of the right limb. Another way to look at it, the right limb is slightly weak just right of its middle.
Easing off the inner 1/3 will take some load off the slightly weak point... it's all interconnected and that's something that some find difficult to grasp.
You don't have to actually strive for stiff tips, they are automatically stiff due to the reduced leverage . e.g if you clamp a bit of 5/16 arrow shaft in a vice using soft jaws with just an inch or two sticking out you will struggle to break it. But if you have 10" of shaft to give leverage it will easily break.

Hold something round like a CD or saucer up in front of the screen and move it until it fits nicely to the curve of the right limb. Do the same on the left limb and you'll see that you have to move the CD closer to your eye as it's a smoother larger radius curve on the left limb.
Try it and you should see what I see, but fiddle around and draw your own conclusions too.
I've used MS paint to draw a couple of ellipses to try and get a best fit for each limb which shows what I mean. It may be slightly exaggerated as I did it a bit quick.
Some observations:-
Generally you do want the lower limb a little stiffer. I'm talking about subtle changes, a few stokes of a bastard file or cabinet rasp, then exercise the bow. Better to do too little and repeat than to overdo it. Another way to focus your eye and your thinking is to look at it and ask... if I drew that back until it broke, where would it break? (I'd say 2/3 of the way along the right limb, measured from the grip).
Another small consideration, always best to support the bow just below the arrow pass, near centre where the hand will support it, but pull the string from where the fingers will pull (this is more critical on short bows).
A tiller arrangement with a pulley and rope is better as it allows you to watch the dynamic movement of the bow. I always video the bow being pulled back and forth so I can watch how it moves.
You've done well, but a little attention to the tiller now will give a better shooting, longer lasting bow :)

Del tiller.jpg
 
Last edited:

oldnut

Supporter
Supporter
that's an impressive eye you have the del, even knowing where to look I still cant see it!
 

geoffretired

Supporter
Supporter
Del, lovely post!
I very nearly posted something earlier but thought I would wait for you, so I could post it and you could tell me what you think.
I read somewhere that some bowmakers draw with chalk under the limbs then turn the bow left to right and see how well the two curves match one another. Does that make any sense and is it worthwhile?
 

Del the Cat

Well-known member
Del, lovely post!
I very nearly posted something earlier but thought I would wait for you, so I could post it and you could tell me what you think.
I read somewhere that some bowmakers draw with chalk under the limbs then turn the bow left to right and see how well the two curves match one another. Does that make any sense and is it worthwhile?
Yes makes sense... but like all these things it needs some caution as a bow (when being drawn by an archer) isn't symmetrical. If it is tillered and drawn from dead centre, the lower limb will likely be a tad weak.
Where I've drawn ellipses for each limb, one can try to do a best fit for the whole bow, but that only really works for full compass tiller (see pic)... but it does show the stiff grip/ mid limb bend. It really just shows that with a stiff grip you need to to try and fit the curves to the individual limbs.
I often see people having drawn some semi random poorly fitting ellipse or circle and then trying to draw a conclusion from that... much of it is down to the difference between looking and actually seeing!
Del tiller 2.jpg
 
Last edited:

4d4m

Active member
Wow! I'd be made up with that as a first attempt, you should be proud of that!

Making my own bow is something I'd really like have a go at someday. Getting hold of suitable wood is the biggest barrier to me; I just don't know where to go.
 

geoffretired

Supporter
Supporter
Thanks, Del.
I guess the more I read about these things, the more I realise that mass production( as in one shape fits all) just doesn't work for a one piece bow.
Or put another way; mass production requires all the bits to be sliced up to make each piece as similar as possible to its counterpart. That way, the " equal" bits can be assembled in the same way for every bow.
It also seems to me that there is a huge amount of knowledge that has to be discovered by trying and improving, before a bowyer can stand a decent chance of a successful end product. It's not just skills with tools; it's knowing how to find the bow that is inside the piece of wood you start with.
 

osprey

Member
Thanks Del
Most appreciated. I'll have another go getting the curve right on the weekend and let you know how I get on.
 

Del the Cat

Well-known member
Thanks Del
Most appreciated. I'll have another go getting the curve right on the weekend and let you know how I get on.
Don't do too much at a time, maybe just a cabinet scraper on the crown of the belly on the inner 1/3 of the right limb :)
Remember it's easy to take it off... but very hard to put it back on!
Del
 

osprey

Member
Wow! I'd be made up with that as a first attempt, you should be proud of that!

Making my own bow is something I'd really like have a go at someday. Getting hold of suitable wood is the biggest barrier to me; I just don't know where to go.
I know exactly what you mean, I'm really struggling to get suitable wood at a sensible price for a beginner. I got this one as a set of two on ebay as partially made bows. They "just" need tillering and finishing. That is a big "just" though :). As I'm new to this I'm happy to take one step at a time.

I managed to get what looks like a suitable piece of Ash from Axminster Tools. They have some wood on display, but getting bits with straight grain is a challenge. You may be lucky to get one piece in the whole store. The board I got was quite big, about 7' x 2" and looks a bit ominous at the moment. I've debarked it, but it is testing 15 - 16% humidity on the meter so I probably won't do much with it until the weather warms up and dries it out a little.
I'm still looking for a source of fresh Hazel. That will be a real challenge making a bow from a tree trunk.
 
Top