Primitive Archer

Main Discussion Area => Bows => Topic started by: DC on September 12, 2017, 11:39:15 am

Title: Detecting set
Post by: DC on September 12, 2017, 11:39:15 am
There are a few threads discussing the nuances of tillering for no(or little) set. I can pretty much follow the logic of the tillering methods talked about here but they usually say something like "stop when you see set". A few have mentioned using a tracing of the unbraced bow. I have tried that and it does work pretty good but there must be others. You can't all have photographic memories. So, how do you see the set in time?
Title: Re: Detecting set
Post by: Badger on September 12, 2017, 11:59:55 am
DC, I don't use a visual method, I measure the weight of the bow at bench marks I establish and if I see it dropping I know I am getting set. You can have a bow take almost no visual set but still have taken a lot of internal damage.
Title: Re: Detecting set
Post by: PEARL DRUMS on September 12, 2017, 12:22:59 pm
I don't pay that much attention until I'm done. I hold it up against my shop wall when I start and when I'm done. That's how I know. I probably sound like a sloppy builder, and maybe I am. I just build the bow that comes off my saw. It takes whatever set it takes. Its not like I'm going to stop on the dime and toss it in the junk can because I notice its taking some set. If I see too much too soon, I will usually stop and sit on top of the register to dry down more.
Title: Re: Detecting set
Post by: DC on September 12, 2017, 12:52:12 pm
DC, I don't use a visual method, I measure the weight of the bow at bench marks I establish and if I see it dropping I know I am getting set.

Then what is your next step? What do you do about it?

Quote
You can have a bow take almost no visual set but still have taken a lot of internal damage.

So, if there is no particular location that the set is happening, then that means you are trying to get too much weight out of that bow?
Title: Re: Detecting set
Post by: DC on September 12, 2017, 12:55:30 pm
I don't pay that much attention until I'm done. I hold it up against my shop wall when I start and when I'm done. That's how I know. I probably sound like a sloppy builder, and maybe I am. I just build the bow that comes off my saw. It takes whatever set it takes. Its not like I'm going to stop on the dime and toss it in the junk can because I notice its taking some set. If I see too much too soon, I will usually stop and sit on top of the register to dry down more.
Well, it works. I got to shoot the Elm bow you gave Goat. The word "covet" springs to mind ;D ;D It sure felt like more than 32#.
You always seem to suspect wet wood for set. Do you live in a damp climate?
Title: Re: Detecting set
Post by: PEARL DRUMS on September 12, 2017, 01:10:30 pm
I live in a moderate climate where our average is around 45-50%, Michigan. I have come to suspect wet wood as the culprit because it is more often than not, providing all other aspects are covered.
Title: Re: Detecting set
Post by: PEARL DRUMS on September 12, 2017, 01:12:10 pm
I'm glad you liked that elm bow, Don. I told goat I was never totally happy with it, but couldn't decide why so I shipped it off "as is" :)

And PS, that's Olivia's bow!
Title: Re: Detecting set
Post by: SLIMBOB on September 12, 2017, 03:02:03 pm
+1 PD. If I get the tiller right from the moment it starts bending, and never let it get over stressed, then set should be minimal assuming my design is proper for that bow.  Too short or narrow for that bow will result in set, exacerbated by uneven tiller. Good design is where it starts.
Title: Re: Detecting set
Post by: DC on September 12, 2017, 04:04:30 pm
Maybe to clarify a bit. I can tell when a bow has taken set and I pretty much know what causes it. What I have trouble with is seeing where the set is coming from. Like what inch or so is too stressed and should be left alone.
Title: Re: Detecting set
Post by: SLIMBOB on September 12, 2017, 04:18:56 pm
Straight edge tells me that.
Title: Re: Detecting set
Post by: sleek on September 12, 2017, 04:19:12 pm
Perhaps a good way is to compare it to the outline you draw on the wall every inch of draw length you gain?
Title: Re: Detecting set
Post by: George Tsoukalas on September 12, 2017, 04:45:47 pm
I take the stave and put the handle up against a wall and measure the tip deflection from the back of the tip to the wall.

Set cannot be avoided but it can be minimized starting long before the stave's first stringing and even before the first sharp instrument cuts into the stave.

Jawge
Title: Re: Detecting set
Post by: willie on September 12, 2017, 04:51:29 pm
use a gage block with a hole for your pencil. I think that eric has recently illustrated the embedded nut feature he incorporated into the gizmo.

A sharp pencil point lets you see small differences
Title: Re: Detecting set
Post by: DC on September 12, 2017, 06:32:22 pm
Most of my staves have some wiggle. Gizmo doesn't work on wiggles. Don't think a straight edge would either. Comparing it to the outline, I mentioned that in the first post, I don't think that's the only way. How many use an outline? I got the impression there are only a few.
Title: Re: Detecting set
Post by: sleek on September 12, 2017, 06:39:45 pm
Most of my staves have some wiggle. Gizmo doesn't work on wiggles. Don't think a straight edge would either. Comparing it to the outline, I mentioned that in the first post, I don't think that's the only way. How many use an outline? I got the impression there are only a few.

I use an outline when I am making short bows. You have less room for error. Lingerbkws, eh, dont care.
Title: Re: Detecting set
Post by: SLIMBOB on September 12, 2017, 06:52:31 pm
The straight edge will work on bows with a bit of waggle.  I typically heat that out as I prefer a flat level belly.  But even with odd areas, you just account for them.  On areas that are bending too much, I put an X through that area on the belly.  I take wood off the areas outside the X, leaving it alone.  Somewhat of an eyeball thing, but just monitor the gap.  I have used the outline many times and it works fine.  It's just quicker for me to use the straight edge.  I do like Jawge mentioned in that I put the tips against the wall and measure to the back of the handle.  With any reflex your tips are forward the handle.  If I see that measurement start to drop I know I need to assess where.  That's when I use the straight edge and compare it against what I had earlier.
Title: Re: Detecting set
Post by: willie on September 12, 2017, 07:09:49 pm
DC

I should have been more explicit about the gage block. the pencil holder can be like the one in the gizmo.

the block it's self can be round, about the size of a loonie, flat on the bottom, but  about an inch or so tall, so that it always contacts the same point on the back when the bow is laid on it's side on the bench.
Title: Re: Detecting set
Post by: DC on September 12, 2017, 07:35:26 pm
Do you have a picture Willie? I'm not following you.