Question on tillering

[Carson (CMB)]

In general, is it best to strive for equal bend throughout length of limbs throughout tillering process , or do some find less set results when getting the fades working first and then outward, or starting with getting mid-limbs moving first, or working out then in...or just do what you can and hope limbs are equal in the end? 

In my first two bows, I feel like the 2 inches of set resulting from tillering process is mostly due to my inexperience.  Trying to take my time and avoid straining limbs before they are ready to move, and trying to keep limbs equal throughout the process, but still seem to get a bit more set than I would like. I know flipping the tips and relflex can offset set, but I would like to first minimize what results from the tillering process, so that reflex or flipped tips are maximized.

[Del the cat]

Maybe I missunderstand the Q, but here's how I see it.
First get the limbs equal by measurement and by floor tiller.
Then onto the tiller and work on the curve of the whole of bow.
You can't just tiller one limb at a time or say the roots first then the tips.
You will doubtless need to work on one area at a time or one limb at a time but only to get the whole bow evenly tillered.
E.G You work on the area that isn't bending as much as the rest. typically that may well be near the grip, but it depends how accurately you have roughed it out.
The aim of tillering is to get the whole bow as even as possible as early in the process as possible, and then to slowly increase the draw whilst adjusting the weight until you hit target.
If you don't get it pretty evenly tillered by the time you reach a good brace height you are in danger of leaving it too late... as a good brace height is about 75-80% done IMO.
Have a look at the little tillering videos on my website to see how I do it and hear my thought processes as I do it. (google delsbows to find the site).
Del

[mikekeswick]

Put simply tillering is the 'art' of get a stave to bend correctly.
Just as Del says you must strive for perfect bend (depends on the layout of the front profile) as soon as possible.
When you get set its because that area has been over strained at some point and it's been over strained because it was too weak.
When an area of limb is too weak it is getting forced to bend too much a) because it is thinner than the rest and b) because the rest of the limb that is too stiff isn't being bent as much as if there was no weak spot in the limb. So it's like a double hit. You really need to have the limb as even as possible in strength and with a suitable taper before it is bent much at all.
It is also possible that your tiller was ok but you tried to brace it too early. I often see people with a barely floor tillered stave braced! I normally take the bow to at least 20 inch on the long string before thinking about a low brace height. The long string is where the majority of tillering should occur because the bow is under a fair bit less stress than when braced. Once braced you should only be fine tuning the bends.
But hey it's not easy and it took me a long time to fully appreciate these things.

[Badger]

   Years ago n this sight DCM posted, " Never bend the limb any further than what it takes to see a correction" It was real good advice.

[PEARL DRUMS]

Floor tillering can get your tiller VERY close if you use your good eye to view down your leg as you flex it, close one eye it helps. My last bow needed about 5 minutes of work on a short string to get a good tiller. It ALL starts with the taper you work into the limbs before you ever bend them. If that taper is even you will have very few flat spots to work out. Tillering is truly an art. Anybody can build a bow, but tillering a bow is another thing.

Flipping tips will increase set because your essentially shortening the limb and making it work harder. Flipping tips will move your tips forward after set has occurred and increase performance some. Unlike Mike, I dont use a long string anymore. I floor tiller to very,very close and brace it short. But that is something I picked up after a bunch of builds. You start to know how thick the limbs should be, you start to know how a perfect floor tiller looks and you start to know how a 50-55# bow should feel on the floor. All that comes with experience and adds up to good tillering practices. SET HAPPENS by the way, dont get overly upset about it. We are working with wood, not a fiberglass sandwich with a sliver of wood. Have fun and sorry for my long winded blowhard!

[johnston]

The previous posts have told you all you need to know about tillering. But it wont come clear to
you until you have done it a few times(and Pearl's floor tillering is at the master level and lord
only knows how many that takes).

Cutting out and shaping a bow, even doing the finish work, is a matter of hand skills which get
better with time. Tillering, as has been said , is an art and it gets better through repetition. I just
finished my 12th bow but have tillered a hundred or more pieces of wood. I picked up fallen limbs,
cut green ones,pulled broken broom handles out of trash, cut strips off scrap lumber and tried to
make'em all bend. You play like you practice so I was serious about it and it really helped me.
Two feet is a good practice piece.

One last thing, set is not a bow killer so do not obsess about it.

Lane