Advice on ash stave suitability?

[Ruddy Darter]

I got this ash stave with has tight growth rings and have read that's not a good thing, I thought I'd post some pics after I've roughed it down and squared it up and was hoping for some advice on its suitability for 100 sort of draw weight or if I'll be wasting my time. I got 36mm x 30mm at the centre and roughly 73" ntn. I had to remove top two growth rings because of bug activity and some spalting at the ends which is now mostly removed.
I'd appreciate any advice.

R.D.

[peacefullymadewarbows]

The only thing spooking me a bit is that it's 73" long. With big ringed ash that'd be no problem for 100#. But those thin rings would like a bit more length BUT ash is very good in tension. I'd say a light belly toasting and a round arc tiller are worth a shot for 100#. Keep your cross section rectangular with rounded corners for stress distribution. You can also burnish the back to add a bit reassurance in tension. I've only done it on cedar and yew but the science works on all wood in theory. I think Dean Torges has positive experience with it on osage. Hope this helps.

[Ruddy Darter]

OK, thank you peacefullymadewarbows, I'll give it a shot then. I may settle for  a 30" draw if I can get away with it and may also downsize some as not to squander the chance of a lighter Elb of sorts.

 R.D.

[Del the cat]

I'm sceptical that burnishing achieves anything on wood.

Ah just found a technical journal article on the subject...
It does increase the hardness but unfortunately they don't consider the tension properties.
I only skim read the article.
Maybe it is worth study, maybe it implies that burnishing the belly would be of more value especially as woods are generally better in tension anyway?!
https://journals.sagepub.com/doi/pdf/10.1177/0954406216641711
Del

[peacefullymadewarbows]

Thank you for that article Del. It made me think I might try some samples of sapwood that were directly adjacent to each other in a stave and make them the exact same dimensions and burnish one and leave the other alone and do bend tests. Although at the very least it sounds like burnishing can protect from denting on the back of a bow via making it harder. Kinda like pre-denting the whole bow back already.

[meanewood]

I don't think burnishing the back would help the first couple of rings to stretch and return undamaged, which is what is needed!

You would be increasing the surface tension on the fibres, decreasing elasticity.

It may be beneficial to burnish the belly however for the same reasons, but to 'damage' the natural integrity of the wood is probably not a good idea.

Heat treating is less radical and probably just hardens the belly by forcing moisture from the outer rings.

[ksnow]

I don't have any experience with 100# plus bows, but plenty with ash. Bug activity, spalting and thin rings for me spells disaster in ash. Others may feel differently.

Hope this works out for you.

Kyle

[Ruddy Darter]

Thanks ksnow, seems worthy of a try.... I worked on it some more and I'll post on how it  progresses.

 R.D.

[WillS]

For what it's worth, I've made two ash bows with heavy bug damage on the back, going through a number of rings.  One at 120lb and one at 145lb. 

Personally, I wouldn't bother with burnishing, I'd focus instead on a very good heat treat (målming is even better if you have the time and patience) and a perfect tiller.  Ash won't let you get away with hinges, or even traces of hinges, once you're over 100lb. Make sure you heat treat at around 20", and again at full draw.  It's no use heat treating once the bow is taking set, you want to get in there beforehand.

[Ruddy Darter]

Thank you WillS,
That's the sort of game plan I had in mind. The stave has cleaned up pretty good and feels solid, just got little remnants of some spalting in the last 5-6" of one outer limb.
Hopefully a little session sometime soon and I'll be ready for tillering.
 R.D.

[Ruddy Darter]

Have I got the grain on adequately?, it moved about a bit, mainly top limb 1st picture, when squaring up. It's pretty much on final dimensions and wanted to check before I round the belly. Thanks for any opinion.

R.D.

[Pat B]

I'd round those back edges too before stressing the bow...but you know that anyway. 
Gonna be an interesting build. 

[Ruddy Darter]

Thanks Pat B, yep, I'm aiming to put an angled trap on the back a fair bit too.
 
 R.D.
...just added a pic of the trap I put on the back, and one of the belly view now rounded.

[Ruddy Darter]

Started tillering the bow, I got it 70@20". Thought I'd show how I'm getting on, hopefully get a 100 drawweight.
Some work on the tiller, some heat treating and a fiinished bow soon hopefully. (pics removed)
 R.D.

[peacefullymadewarbows]

Nice progress. Hope it finishes up well. Excited to see it.