Trad Gang

Main Boards => The Bowyer's Bench => Topic started by: Vgo750 on January 19, 2014, 11:44:00 AM

Title: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on January 19, 2014, 11:44:00 AM
White oak bow I steamed for 40 minutes and bent and clamped to a caul.  Bow bent really easily but i ended up with a crack and a fret.  Does this look terminal?  I think the fret will be tillered out as I did leave a little bit of extra meat on the tips.  Now the crack I'm thinking I can get around from thinning and rounding the tips as they are still like 3/4" wide.  Those with experience in this situation am I right in thinking I can get past this?
   (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo3.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo3.jpg.html)

Crack
   (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1.jpg.html)

Fret
   (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo2.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo2.jpg.html)
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: mwosborn on January 19, 2014, 01:58:00 PM
Looks like your tips are still pretty beefy - like you said as you reduce the tips down you may get rid of both.

Couple of suggestions for the next one - I would wait to file in string grooves until after you have the tips bent.  Also, I use piece of aluminum strap between my clamps and wood - reduces the chance of splinters.

I have never tried to bend oak (which might not be as easy as some other woods), but to get the wood good and hot I wrap a wet rag around the area to be bent and then steam for 45 minutes or so depending on thickness.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Bowjunkie on January 19, 2014, 03:30:00 PM
That's not a fret(compression failure) my friend, that is a break due to tension resistance failure. It looks like it started at the string groove, then ran up and then across. I would shorten the bow enough to remove the damage if possible, or if not, then I would shape that limb tip real quick, removing all of the damage in the process, and see if there was enough wood left for it to work.

You have a clamp to either side of the string groove... one right on the tip, and one a little farther down the limb. Next time, put your first clamp right ON that string groove area, not right on the tip, with a plywood pad to distribute force between the bow and the clamp, then work your way down he limb. I never clamp directly down on the bow wood. I keep a bucket full of pads made with 1/2" plywood of various lengths to distribute both the crushing force and clamping area pressure. It might have helped greatly in this instance.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Eric Krewson on January 20, 2014, 08:00:00 AM
I would cut the bad wood off flat and glue on an underlay to strengthen the wood in that area.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: LittleBen on January 20, 2014, 08:23:00 AM
X2 what Eric said. I've done that in the past.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on January 20, 2014, 09:58:00 AM
i went ahead and flipped the other side as well...if anything at least for practice...and It went perfectly no cracks or tics or anything.  I'm going to try to shape out those cracks and add an over or under lay...hopefully that will be strong enough.  this bow is 64" ttt and i am not wanting to take it down to ~60"
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1-1.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1-1.jpg.html)
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: KellyG on January 20, 2014, 01:57:00 PM
I would just file it down and see how much wood I have left and do the other side to match. It does not look too deep in the pics.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on January 26, 2014, 06:48:00 PM
Well I attempted to file and sand out the cracks and low and behold...they SEEM to have sanded out!
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo4.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo4.jpg.html)

 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo5.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo5.jpg.html)

I have continued on with the build and thus far I am at a very short brace, like an inch, and here is where I stand.
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1-2.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1-2.jpg.html)

Now this is my first bow with any bend in it and I'm just looking for any helpful tips.  I'm at ~50lbs right here and aiming for ~60@28.  How do yall think she is looking so far?  Any tillering advice?

As always, thanks very much for the help.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: mwosborn on January 26, 2014, 06:58:00 PM
Glad it sanded out for you.   Looks like the right limb has a flat spot in it maybe 6" out to just past mid limb.  Let's see what the tillering experts say.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: takefive on January 26, 2014, 08:13:00 PM
I agree with Mitch, but a tillering expert I am not.  Two things that have helped me in my ongoing quest for even tillering are a Gizmo and an inexpensive dial calipers.  Good luck on your bow!
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on January 26, 2014, 10:15:00 PM
Thanks for the advice...somehow i totally forgot about the gizmo...busted it out and it told me, just as mentioned, a flat spot on the right and also too much bend in the outer third in the left...i carved and pulled it out another inch or so...better but still need more. I will keep posting as i go along. Thanks everybody!
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: LittleBen on January 27, 2014, 11:11:00 AM
Just a tip on steam bending, the closer you are to floor tiller the easier it is. Problem usually arise when you try to steam bend a piece of wood which is too thick.

Try getting the tips reduced in thickness well before steaming. That will help. Remember, if you get them too thin, you can always add an underlay of very thin wood. even .060 will turn a bending tip into a very stiff one.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on January 28, 2014, 08:42:00 AM
another short carving, gizmo'ing, pulling session...at 50lbs again.
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1-3.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1-3.jpg.html)
For those of you that have done flipped tips or very minor recurves before, are yall thinning the tips as thin as you would a straight profile bow?  I'm wondering if I shouldn't leave tips slightly wider and thicker or just thicker than I would a straight profile bow.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on January 28, 2014, 08:59:00 PM
Continuing on.  Here I sit 50@24.  
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1-4.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1-4.jpg.html)

I am shooting for 60@28 so I think I will just keep carving and pulling for another couple of inches...and then really spend a lot of time sanding and rounding edges and finishing this bow.  On my previous bows I haven't really spent that much time on really make them look nice but I think I will try on this one.  I have been using the gizmo since about 20" but I ALWAYS appreciate help.  As always, thanks for looking.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: John Scifres on January 29, 2014, 06:45:00 AM
Work the midlimb on the right a bit more.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: LittleBen on January 29, 2014, 01:18:00 PM
Just a heads up, once you're done tillering, you can whack off about half the length between the string nocks and the limb tip. You need very little beyond the string groove. Just enough for a stringer on one end, and less on the other end.

I usually leave no more than an inch on one end and probably 1/2" on the other.Easy way to reduce tip mass.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: takefive on January 29, 2014, 01:34:00 PM
I try to keep the reflexed tips stiff by leaving the wood a little thicker.  I still narrow them (3/8" is as narrow as I go and then add an overlay) but keep them thick enough to hold the reflex.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on February 20, 2014, 01:27:00 PM
Pretty much finished with tillering I think.  I am at 28 inches & 52lbs and the bow draws really smooth and shoots pretty good...does have some wrist slap for sure though.  I still have several things to do to finish up but what do yall think of the tiller?  A question...I wanted just a few more lbs @28.  Now I have heard white oak takes to heat treating really well.  Would a decent heat treating this far along change the tiller at all or would it maybe just add a few lbs and a few fps?  I am ok with the tiller of this bow from a looks perspective...but not thrilled...I like a little bit more bend in the fades I think.  I probably should have been more patient and scraped less at a time before re-checking.  OH YEA...one thing I was going to mention...So the last time I worked on the bow...i was actually at ~60@28 roughly.  I went to rounding and sanding pretty aggressively and tried my first attempt at trappin the back.  Well I didn't think I trapped so much but MAN the next time I checked I was a full 5lbs lighter!  I didn't realize trapping removed so much draw weight.  Anyways..pics
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/28.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/28.jpg.html)

in hand:
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo4-1.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo4-1.jpg.html)
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: John Scifres on February 20, 2014, 05:47:00 PM
That looks great.  Nice job!
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: takefive on February 20, 2014, 09:49:00 PM
Tiller looks great.  Congrats    :thumbsup:   If I remember right, Marc St. Louis wrote about toasting the belly of a bow that he'd done the final tillering on in TBB 4 with good results.  He said that it improved cast, but I don't remember what kind of wood it was.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: LittleBen on February 21, 2014, 09:25:00 AM
I have heat treated red oak with suprisingly positive results ... makes a real bow wood out of it. I'd imagine white oak will also respond very well.

It is likely to change the tiller though, because it's nearly impossible to heat treat it uniformally, but the tillering should be really minor.

You could potentially gain ALOT of weight with heat tempering oak. I wouldn't be suprised if you gained 10lbs ... probably more like 5-7lbs.

If you do decide to heat treat, make sure you do it with the bow clampsed to a form so it doesn't twist etc. Also be casreful not to let the back get toasted, it can cause tension failure if the back is heat treated at all.

Good luck.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on February 28, 2014, 01:10:00 PM
I went ahead and did me some heat treating.  One limb at a time like so:
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo2-5.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo2-5.jpg.html)

I was very conservative with the reflex I bent the bow into and...complete success!  left limb finished and right limb for comparison:
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1-5.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1-5.jpg.html)

The right limb turned out pretty good also but didn't quite hold as much reflex/straightening.  What a learning experience this bow has been!  I never realized how simple 1) steam bending a bow is and 2) heat treating bows is.  I will probably do both to all my builds going forward.
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: Vgo750 on March 19, 2014, 10:15:00 PM
Well while shooting the bow in I noticed a crack on the back.  
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo1-6.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo1-6.jpg.html)
 (http://i777.photobucket.com/albums/yy54/91mr2_album/White%20Oak%20Flipped%20Tips/photo-1.jpg) (http://s777.photobucket.com/user/91mr2_album/media/White%20Oak%20Flipped%20Tips/photo-1.jpg.html)

It's really not all that deep so i'm thinking I can still save her.  After picking up some good weight via heat treating I am currently sitting at 52@28.  I have a couple good hickory backing strips I cut a while back...good grain.  Can I sand down the back of the bow all the way past the crack and then glue up one of those backings?  I would be fine with a high 50's or low 60's bow but I don't want to pick up TOO much weight.  I figure that I will drop several lbs by sanding down past the crack before glue up.  Has anyone ever experienced a crack like this and remedied with a backing?
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: mwosborn on March 19, 2014, 11:24:00 PM
I have had bows develop splinters similar to that - I super glued them back down and backed with rawhide.  I suppose you would be able to sand down and back with a strip of hickory too.  What is that cute little thing in the back ground?    ;)
Title: Re: W.O. Pyramid flipped tips board bow...another crack :(
Post by: red hill on March 19, 2014, 11:49:00 PM
Looks like part of his tribe, Mitch.  LOL!

I've glued a splinter down and then glued a hickory backing on with success.  I'd do it again if the splinter isn't too deep.

Good luck. It's a nice looking bow