Primitive Archer
Main Discussion Area => Bows => Topic started by: Prarie Bowyer on April 28, 2012, 12:25:42 pm
-
I chrysaled a limb on a bow I've spent WAY too much time on to pitch. I confes I began to have BOM thoughts.
http://www.bowyersedge.com/patch.html
The belly wood is Ipe. Should I use a scrap of Yew, Osage? or more Ipe?
The discussion that I'm hoping will unfold is "Yes I use that patch al the time and it works like a charm. I'm having trouble fathoming how it can work because I'd think the mechanics of the bow would send the plug shooting back at the archer.
-
There was a bow on here not very long ago fixed like that.
-
I fixed a bow using that techique about 3 years ago. The patch is still holding fine.
I would use Ipe in your case.
-
Oh I have Hickory also which I think is a bit more flexable in that respect. Why must it be quarter sawn? I'm not certain I can get patch in Ipe that is quarter sawn.
Thanks again.
PB
-
Ipe is so dense it won't make any difference what grain orientation you use.
-
3 years ago :) How often is it shot?
-
Oh, I've probably put about 1000 arrows through it since.
-
Awesome.
-
I've done a couple like that. You certainly don't want to use hickory, as it's weak in compression. Ipe would be the ticket, as would osage. I always use URAC for this application, as it has gap-filling properties that glues like Titebond don't. Titebond and the like therefore require the surfaces to mate perfectly, which can be tricky in this instance.
-
The first one of those I did was probably 10-ish years ago. I was meticulous in fitting the patch perfectly and clamped it solidly, as if it were a backing strip. I couldn't bear to fit anything that wasn't absolutely perfect, as Dean's article recommends against. Soon after, the patch started to crack along the glue joint. I showed it to Dean at a rendezvous, who told me the feathering angle was too severe and that my clamping starved the glue joint. He said something to the effect of, "This is the only case where sloppy craftsmanship pays dividends." I listened to his advise and have done several more of those patches over the years, exactly as he describes. All have held fine.
-
You guys are making me happy!
Well I used Ipe. I cut the piece so that the "belly" in terms of ring growth was the belly of the bow. I got lucky and got a great fit. I scrapped it up with my grooving scraper and clamped it with little hobby clamps and Urac. It sucks that Urac is soon to be no more. But he discusses another option.
I'm so stoked over this fix. I was about to serve the string and put in the arrow passes.
-
No clamps! Or at least no more pressure than it takes just to hold the patch in place. That's one of the key successful elements.
-
the little hobby clamps slip and don't hold "tight". mostly holding it in place with light pressure.
I'm so stoked over this patch. I hope it works out. It's a great excuse to keep the bow for me :laugh: I seem to wind up giving, trading or selling my bows away almost as fast as I can make them. Now I'll be like "Patched that one, not certain about it's future, testing/observation in process, can't hav it". >:D Or give it to my brother... ;)
-
I use a similar method but I use a hole say to cut my patch out of the raw stock and a sanding drum that just fits inside the hole saw on the bow, will give you a perfect fit. I have been doing them with tightbond. Have only done a few but they work, I have a plum bow I am getting ready to do.
-
Oooo Plum! I'd like to see a pic of this. I serriously consider using a contrasting color just for the sake of it. Wonder how maple would do in this situation?
-
I'll try to get a pic up tomorrow. My patch came out almost invisible save where I grooved it and the glue trench shows in a few places. Oh and the patch is standing slightly proud of the belly as per the instructions.
In the future I'll try and make a grain matching template. You just take a piece of paper and mark some grain lines from the belly on it. then move that around on the piece that scrap will be cut from till you find a spot where most of the grain lines line up with the tick marks.
-
I haven't strung it yet but here are pics of the pach after carving it down. Carving Ipe and Urac is a great way to dull a good chissel. I realized that the quartersawn grain recomendation for for ease of carving. Fortunately I'm a carver of some tallent so it wasn't a problem. The ohnly thing I'd add is that it can be scrapped with micro scrapers made from broken hacksaw blades. Pics of the patch.
(http://i235.photobucket.com/albums/ee59/scottnlena/IMG_3601.jpg)
(http://i235.photobucket.com/albums/ee59/scottnlena/IMG_3602.jpg)
-
Lookin good,
How did you make micro scrapers from hacksaw blades?
-Billy
-
Grind the teeth off. That is the best edge but the back works also. The radius section on the ends is handy for detailing. You can use a Dremel and a small grinding wheel to regrind them into different shapes.
Scraping usualy gets a better finish than sanding faster. IN some woods like maple and boxwood it's the only efficient proposition. Maple for example makes it difficult to skip sanding grits because the previous grit scratches will show unless you use power sanding or are prepared to make a career of it.
Take for example the carving in the video below. There was zero sanding on that. It is self harvested Rock Maple from NJ. Yes it took along time, BUT it goes faster if you use a mallot for everything AND scrape not sand. I did grind some areas with 80 Grit sanding belt pieces glued to a shapped stick. Then right to the scrapers and sharp chissels for final finishing and polishing.
http://www.youtube.com/watch?v=dyBWrlobktw&feature=plcp