No Set Tillering

[Badger]

No Set Tillering
     No set tillering is a simple way of monitoring the condition of your bow that does not rely on a sense of feel. Instead we use our scales. Whenever a bow starts to take on set or takes on permanent deformation in compression we will have a corresponding drop in draw weight. Your scales will pick up on this before it becomes visually apparent. When we are bringing our unfinished bow down to its target draw weight we want 100% of its reduction in weight to come from wood removal and 0 % of its weight reduction to come from breaking in the bow which is just another word for set. No set tillering can be used on the long string as well as the braced bow.

    This is how it is done. ( long string method) We get the bow bending as evenly as possible with only a small amount of tip movement. We install the long string lets say it hangs down about 6“. Assuming the bow is bending evenly we pull the bow to about 25# and carefully note where on the yardstick it was when we hit the 25#. Lets say we hit 25# at 14“. We move down one inch at a time drawing it further each time as we inch toward our target draw weight (50#). As we move down we also are looking for spots on the limb that need adjusting.

     Each time we advance an inch on the long string and exercise it there we go back to our benchmark at 14“ to see if it has changed. If it has dropped that means the bow is taking set and we need to take action. Lots of reasons a bow might be taking set. Wood is high in moisture, not enough limb bending, bending too much in one place, design is too narrow for the weight you are asking of it. The obvious remedy is to figure out what the problem is. Too little mass is the most common tip off for an under designed bow.

    Suppose once you get to 18“ you see a few spots that need attention and you decide to scrape some wood off. Once you are done scraping the wood go back and start over resetting your benchmark weight at 14“. Every time you remove wood you will need to reset your benchmark weight. If I am using a long string I usually do this until I hit my target weight at about 24“ and then I brace the bow and start the same process over. If your bow is taking set and you keep going with this same procedure don’t blame the procedure. The idea is that this system will tip you off as soon as set starts happening and give you an opportunity to remedy the situation.

   Feel free to ask questions I may not have been real clear.

[PatM]

If you are  noticing a drop and then re-set your benchmark a couple of times and likely repeat, aren't you accumulating set anyway?

[Badger]

  If you loose weight because of wood removal you are not accumalating set. You have to reset everytime you remove wood.

[PatM]

I mean that you won't really know if the drop is from set or wood removal. If you scrape a bit and the weight has dropped a pound at the benchmark it could be half set and half wood removal unless you really know your scrape to weight ratio.

 

[PEARL DRUMS]

Minimal set tillering may be a better descriptive.

[scp]

There will no set until you bend the bow. 

[Swamp Thang]

Ahhh so basically if you notice the lbs aren't stacking right or make and or limbs not bending ect. Any changes made restart to process....and whatever your new lbs are at the 14" mark is your new beginning

[arachnid]

Thanks a lot Steve. Now I got it.

[willie]

Steve
your no set tillering has worked well for me, and I appreciate the help you have given me when putting it into practice a while back.

I would like to share a slighty different way of applying your method, that works well for me.

Instead of pulling to an inch mark and reading off a weight scale, then going back to the previous benchmark,

I have a series of weights that I hang on the string, and a tape measure mounted on the tiller tree that I can view. I start by measuring the draw length with a 25# weight. the weight only needs to be hung on the string long enough for the tape to be read. Then I repeat with the 25# plus a 2# weight for measuring a new draw length, then repeat with the first benchmark weight. I can observe differences as small as 1/16th of an inch, which equate to approx.  2 oz change in pull weight. I find it easier, as I can work directly in front of the tiller tree, rather than trying to pull from a distance and make the scale settle on a "rougher mark.
 
For me anyways, I can see the the beginnings of set much sooner and watch its development.

swamp thing- yes, at least the way i do it, every time wood is removed, I have to establish a new benchmark. I don't necessarily go all the way back to beginning though, a new benchmark at the draw length previously attained seems to work. 

[bushboy]

Steve do you account for heat treating in your formula?

[Badger]

Steve do you account for heat treating in your formula?

      I don't but it does help make the mas formula work for sure.

[Badger]

Steve
your no set tillering has worked well for me, and I appreciate the help you have given me when putting it into practice a while back.

I would like to share a slighty different way of applying your method, that works well for me.

Instead of pulling to an inch mark and reading off a weight scale, then going back to the previous benchmark,

I have a series of weights that I hang on the string, and a tape measure mounted on the tiller tree that I can view. I start by measuring the draw length with a 25# weight. the weight only needs to be hung on the string long enough for the tape to be read. Then I repeat with the 25# plus a 2# weight for measuring a new draw length, then repeat with the first benchmark weight. I can observe differences as small as 1/16th of an inch, which equate to approx.  2 oz change in pull weight. I find it easier, as I can work directly in front of the tiller tree, rather than trying to pull from a distance and make the scale settle on a "rougher mark.
 
For me anyways, I can see the the beginnings of set much sooner and watch its development.

swamp thing- yes, at least the way i do it, every time wood is removed, I have to establish a new benchmark. I don't necessarily go all the way back to beginning though, a new benchmark at the draw length previously attained seems to work.

   I like that method, more precise.

[BowEd]

arachnid....Using that type of tillering bottom line to me is that a person has to slow down while tillering.Mistakes are nipped in the bud before further progress.It has worked well for me too.
Using the scale along with it weighing mass does help me to know exactly how much poundage is lost to the amount of material removed.Say 1/10th of an ounce removed reduces poundage 2#'s as an example,or 1/10th of an ounce removed gives me 1/8th inch positive tiller from even tiller.It really slows a person down tillering.Getting familiar with the type and condition of wood a person is working with.
I think Marc St Louis mentioned up to a 10% reduction in mass weight from heat treating.Most times at least with hickory here that happens side tillering.

[Badger]

arachnid....Using that type of tillering bottom line to me is that a person has to slow down while tillering.Mistakes are nipped in the bud before further progress.It has worked well for me too.
Using the scale along with it weighing mass does help me to know exactly how much poundage is lost to the amount of material removed.Say 1/10th of an ounce removed reduces poundage 2#'s as an example,or 1/10th of an ounce removed gives me 1/8th inch positive tiller from even tiller.It really slows a person down tillering.Getting familiar with the type and condition of wood a person is working with.
I think Marc St Louis mentioned up to a 10% reduction in mass weight from heat treating.Most times at least with hickory here that happens side tillering.

  Beadman, you are not using the scale to track mass here. You are using the scale to track draw weight loss due to wood damage. 1/8" of set will show a loss in draw weight.

[BowEd]

You took my statement out of context and related it to your mass weight formula badger.Removing wood for a lesser draw weight is'nt removing damaged wood.