A bit of a problem - take down recurve

[Bradford]

So I have slowly been working on this bow.  Had some scraps of wood in the shop and figured it would be a good way to get some ideas worked out.

After HOURS of work.. I was going to do a quick tiller and noticed this:





You can see the gap at the glue line when pulled back half way (about 22 in draw)  I played with it a bit and it looks like the Walnut is flexing to much.



So any ideas?  It is only pulling about 35 lbs.. it is a 64"..  I am sooooo bummed.  I have not had a problem like this before.  I am just worried that maybe the walnut is not strong enough wood.

[Bradford]

Here are some pics of the bow.  I was trying out some new design ideas on this bad bow







So.. looks like I am going to have to build another riser.  Maybe using maple as the main and walnut as the accent.

If anyone has any ideas of a repair, let me know.

Thanks,
Brad

[StoneAK]

I snapped a walnut riser not to long ago but I had the lam thickness wrong so I am sure I over stressed the wood. What kind of glue did you use?

[Dmaxshawn]

I built a walnut riser bow and it failed to.  So from now on if I use walnut it gets a I-beam with phenolic.  Sorry for your bow she's a beauty.  

Shawn

[John Lipinski]

I wouldn't use walnut in such a load bearing role; I've had it fail on me before as well. In decorations and accent strips, it seems fine, but it's a bit brittle and doesn't like flexing too much. At least, that's been my experience with it.

beautiful bow, shame it's giving trouble.

edit: same goes for mahogany.

[Bradford]

Thanks guys.. I used smooth on.  I always cut a center rest shelf, so the maple I beam portion got cut away.. leaving only walnut.

Live and learn  (NOTE to self .. DONT use walnut as main wood!  LOL

I have used maple, ash, dymond wood, walnut/maple laminate, purple heart and yellow heart.. with no problems (as the main wood)

Well.. at least the limbs are still good.

[Glunt]

Second bow I saw on here today with a failure at the reverse swoop on a footed riser.  Tons of stress trying to pull that joint apart when the bow is drawn.  

Very cool bow though!

[Shaun]

Total amount of wood at the area of the separation is small, real small, looks like about 1/2 inch by maybe 2 inches. You have a huge site window cut out that looks like well past center cut and very tall. If you cut clear through the "I" beam it no longer functions. It is a fine line between a "clunky" riser and a weak one. The good news is you can build another riser for those limbs.

[recurvericky]

I just had a riser crack in the site window a few weeks ago. I used CA that is the consistancy of water and is made to fill cracks. I have shot it several times and left it strung with no problems.

[Bow-n-Head]

Yehbut Ricky, U had "professional" help.

[Bradford]

you hit the nail on the head Shaun.. .55 wide and only 1.45 deep.  I knew this was only going to be around 30 to 35 lbs, so I pressed the limits.  Just was not aware of the walnut being so week.

All the smooth on in the world can not keep a softer wood and a harder wood together with the stress difference.

I will super glue the bad parts and put a couple coats of tung oil on her.. use it for show and tell.  I like the lines of the riser.. she looked sexy!  So will repeat with another but with the stronger woods.  And will give a little more beef at the window line.  I like the large windows personally... so has everyone that shoots my bows.

[Aznboi3644]

why not glue a lam on the riser cut out for the arrow shelf...that should thicken it up and make it no flex at all.

May not be "centershot" anymore but it shouldn't break

[Bradford]

but it is bending at both ends?  So what is your thought.. just in the window?.. or elsewhere as well

Thanks for the idea... I am all ears, but don't follow just yet

[Mike Most]

This comes under the not normally done category for bow risers,

but why not put a 2 inch screw from the light into the dark and plug it, (drill a screw hole, fill it with smooth on run the screw in (counter sunk of course) and then put a plug in each end, Might save your 35 lb bow

unless I misread something.

Nice looking work.

[Bradford]

I actually was thinking something along those lines.. but I am still worried that the thin part of the walnut will give way.  Maybe drill straight down and glue in a steel rod?  strengthening the walnut.  Might work.. I will give it some thought when I get home

[Crooked Stic]

You got the riser way too thin there in the crack area plus walnut two bads. Make another riser loose the walnut except maybe for accents. beef it up a bit more in the thin areas. Not a biggy just part of learning.

[T Folts]

I wouldnt try and fix it unless you are the only one shooting it then its on you if you get hurt if/when it fails. .02
Terry

[SEMO_HUNTER]

You might try drilling a hole and pegging it with some dowl material and Urac? Since it's a project bow anyway, may not look all that great but I bet it would hold it together. Just a thought.

I see Mike was already headed in the direction I was thinking. Great minds think alike.

I'd get some good quality dowel or make your own and make the hole just a few thousandths bigger than the dowl so you have plenty of room for the epoxy and peg that sucker.

My bow is doing great by the way, I love it!  

[Bradford]

It is a bit thin (and I knew I was pushing the envelope), but I think it would have held with maple. Especially since it is low poundage.

Just never thought walnut would have acted this way.  But it is all good.

I will just finish up the riser for show and tell. I will use the limbs with another riser.  Gives me something to do.

Semo.. glad to hear it bud!

That is why this bow was NOT a commissioned bow.. had some scraps and figured I would try some new tricks.. I still have my standard pattern for any bows going to others.

[Mike Mecredy]

With those 3 pc take downs, it's best to limit the glue lines in the riser as much as possible.