Black locust

[MulchMaker]

I love this stuff, black locust is easy to get the bark off in winter time, it grows everywhere and strait! It roughs out easier as well. I've seen beautiful heartwood bows on this site and I've seen beautiful heartwood/sapwood bows. You can use it if it's dead or alive. Cool wood. So black locust fans what are your tips and tricks? If doing a mostly sapwood with little heartwood sapling style bow what should I look out for? When doing full on ring chasing big stave style bow anything I should do different than say hickory?  Can you do a green reduction to bow blank then fast dry? I just reduced a sapling down and took the bark off limbs are 1 1/4 inches wide half an inch thick and 6 foot 5 inches in length. I have 4 nice 8 foot  staves drying bark on as I don't know if I should take it off. Thanks for taking the time to read/respond
Zach

[burtonridr]

I will be interested to hear some replies, and hopefully you don't mind me adding a few more questions about this wood.

I have a log about 4 or 5 inches round by 6ft long drying at the moment, I cut it early last spring(feb 2016). I cant wait to start working on it when it dries. From what I read a while back, it is best to slow dry this wood... But I'm hoping someone with experience with quick dry chimes in.

Do you find the staves with bark rust work ok? I have a lot of black locust around here, but they are all covered in like a rusty color on the bark.

Do smaller 1 1/2" to 2" trees work ok for bows? I imagine these have a very rounded back?

[Jim Davis]

I've made a dozen or so locust bows. It seemed to work bestid to make them at least 2" wide at the fades in order to get a bow in the mid #40s. That's if you want to avoid as much set as possible. I always made pyramid bows, which gets you close to good tiller by just keeping the limb a little over 1/2 thick for the full length and only tapering the sides--from the fades to the tips.

I agree that locust has a very nice growth pattern and is often straight and without twist. Much better about that than Osage.

[---GUTSHOT--->]

I'm a huge fan of BL. Once I get my bows to floor tiller I heat heat heat those bellies on a caul and put 2" of reflex in them. Then start tillering. I o my use the heart wood. Don't like the sap.

[Springbuck]

I love the stuff and have done all kinds of things to it and made all kinds of bows from it.  It can take a high crown on the back.  I have poor success with sapwood, but a sapwood back is fine.  It can be tricky to chase a ring because it can wiggle and roller-coaster and have knots like osage, and while the ring texture is distinct, the colors often change, run out, or are all the same.   Chasing down sapwood rings and leaving one sapwood ring or whatever, it is hard to see the early ring.


Locust warps less than a lot of other woods while drying, but can check if you try to dry it too fast..  I like staves from bigger trees with locust, like 6-8" in diameter, while I prefer white woods like elm to come from 3-5" saplings.  I like thick growth rings and thin early rings, and dense wood.  You can back it with bamboo or hickory.  It takes heat treating well.

NOW, the endless jam you hear about BL is that it is weak in compression.  I'm in the camp that says "no" to that, but with some caveat.  Black locust (0.66-0.77 SG) is lighter than osage (0.76-0.86 SG).  BUT it is slightly STIFFER (M.E. is 2,050,000 ft lbs/square inch for locust, 1,689,000 ft lbs/square inch for osage) and has higher crushing strength (10,200 ft lbs/square inch vs 9,380 for osage) BUT, BUT, BUT it's janka hardness is much lower (1700 vs 2760 to osage) and it is a tad less elastic. 

All that adds up to a wood that feels extremely stiff and strong, but is STIFFER than it is ELASTIC.  I can't call that "weak", but a locust bow will be thinner back to front than you expect and still be very stiff.  If you bend it too much too early this stiffness WILL fret the belly.  It's definitely less forgiving of being overstrained, and "overstrained" feels like a design should be able to get away with.  It's not weak, but it is so stiff it'll feel like it should be treated like osage, and you can't do that.  You must count on it being thinner when finished, and wider. 

Osage doesn't grow where I live, and I've only used it a few times.  Locust in my favorite locally available bow wood.

[Jim Davis]

...NOW, the endless jam you hear about BL is that it is weak in compression.  I'm in the camp that says "no" to that, but with some caveat.  Black locust (0.66-0.77 SG) is lighter than osage (0.76-0.86 SG).  BUT it is slightly STIFFER (M.E. is 2,050,000 ft lbs/square inch for locust, 1,689,000 ft lbs/square inch for osage) and has higher crushing strength (10,200 ft lbs/square inch vs 9,380 for osage) BUT, BUT, BUT it's janka hardness is much lower (1700 vs 2760 to osage) and it is a tad less elastic. 

All that adds up to a wood that feels extremely stiff and strong, but is STIFFER than it is ELASTIC.  I can't call that "weak", but a locust bow will be thinner back to front than you expect and still be very stiff.  If you bend it too much too early this stiffness WILL fret the belly.  It's definitely less forgiving of being overstrained, and "overstrained" feels like a design should be able to get away with.  It's not weak, but it is so stiff it'll feel like it should be treated like osage, and you can't do that.  You must count on it being thinner when finished, and wider. 

Osage doesn't grow where I live, and I've only used it a few times.  Locust in my favorite locally available bow wood.

Springbuck, I agree with your conclusions 100%. I do want to point out, however, that every set of mechanical properties numbers for Osage  available ANYWHERE is only the set for green samples. the Forest Products Laboratories did the only extensive tests on American woods and they did not record the numbers for oven-dry Osage, though they did for every other wood they tested. Numbers found anywhere else are merely copied from the FPL tests. Nobody has done any new tests, although some try to make it look as though THEY are the authority.

The result is, that it is impossible to make a realistic comparison between the numbers for Osage and those for any other wood. We are left to our experience.

[JonW]

Have used it quite a bit. My favorite design is a 64"-66" R/D. I have not seen it neccesary to go more than 1 5/8" wide for locust. I have made some short bendy pyramids and have gone up to 2" wide. Heat bends well and likes to be heat treated. Good wood.

[BowEd]

It's many a bow makers' favorite type wood or at least right up there.Including me.Saplings make great flat bellied D bows.Flat bows make excellent bows too.A little wider than osage at the same lengths.No tricks just the basic rules of careful tillering.It's a very quick wood on it's own I'd say without any stressful design put on it.Takes heat treatment well but turns dark the quickest of any wood I've heat treated.
One of my favorite bows I've got is a BL bow puling 54#'s @ 28".63"TTT mild R/D stiff handled lever bow.Only weighed 13.00 ounces after heat treatment.A quick bow even without much set back of the limb tips. Not your usual handle pop off[fix & pics added][finish & pics added]
Many from the Pa love this wood.Just me but your staves I would chase a ring and shellac the back and ends.It'll dry faster for ya too.

[Mo_coon-catcher]

I love black locust. Like everyone has said, it takes heat treat very well. After heat treat it usually set my tiller back by 5-6" at the same weight. I make most of mine 1.5" wide to about 55# unless I make the limbs short and high stress, then I bump up to 1.75". I've never done a fully sapwood backed bow, but I love going to to transition ring. Sometimes you'll get mostly heart wood with streaks of lighter sapwood.. Might be worth trying a flat bellied ELB style with your narrow stave.

Kyle

[George Tsoukalas]

I learned on BL. It is a very good bow wood and one of my favorites.
As a side note it also heat treats well.
Jawge

[MulchMaker]

Thanks for your replies, should I urathane the back of the mostly sapwood bow or since it's reduced enough just let it dry?

[JonW]

A light coat won't hurt a thing.

[Springbuck]

A light coat won't hurt a thing.

Always better safe than sorry.  Slower drying prevents SOME warping, as well as checking.

Asharrrow, I did not know that, or had forgotten it.  Thanks.  That would change the hardness and crush strengths a LOT, along with everything else.  I'm shocked that the US government data base folks couldn't get their hands on a dry sample, when they have so many woods from all over the world.

[MulchMaker]

Thanks guys, hopefully soon I'lll have some beautiful bows to show you, love this locust so far, sure easy to split. Thanks again and good luck on all your endeavors.

[MulchMaker]

Ah ha I found it!!! Jimmy made it and now I want one too! I thought the thread was on another site but it is right here http://www.primitivearcher.com/smf/index.php?topic=35601.0 this was my whole idea for the sapling bow