Lesson learned with Gabon Ebony

Hengelo_77 said:
1) why stabilise ebony
2) there are still scales inbetween the cracks
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Yeah, it's my mistake for not looking up whether or not it needs to be stabilized. I've only worked with Black and White Ebony, and I stupidly assumed they were similar in regards to stabilizing.

I'll be able to get a couple scales out of it, but it was intended for a hidden tang handle, which it won't work for now!
 
Is that really gabon ebony? How and when did it crack, what was your procedure?

I have a lot of african blackwood that looks similiar to this and it will sink in water without stabilizing. With normal (home) set up you will not be able to stabilize and/or there will be no gains from stabilizing dense/oily tropical wood.
 
Some issues to know abut with ebony:
1) IMHO, Cactus Juice isn't a good stabilizer for many things It can cause cracking.
2) Ebony does not like a sudden change in moisture content. It does not tolerate soaking it in anything. Even wiping the surface with alcohol or acetone too heavily can cause surface crazing.
3) Any heat will cause internal stress. If buffed hard, it will shine like glass, and then a day or two later it will be covered with spider web cracks.
4) Use on sharp tools and saw blades, and sharp fresh abrasives. Go slow in sawing and in sanding. If it builds up heat it will usually ruin the piece.
5) Ebony needs to dry for many years, even decades, to become stable. Most online ebony is far too fresh to use. It often ones covered in wax to "protect" it. When the wax is removed, cracks form soon due to the fact that the wood is still pretty green inside.

Ebony is more trouble that it is worth for many people. African blackwood is a more popular substitute.

When someone points out that ebony was used on folders, musical instruments, and other things for centuries I reply that is was properly cured and aged before those things were done. Also, that was ebony that had grown for as much as a century before harvest. Much modern ebony is farmed and forced to grow as fast as possible, then harvested at a much younger age than in the past.
 
Stacy E. Apelt - Bladesmith said:
Some issues to know abut with ebony:
1) IMHO, Cactus Juice isn't a good stabilizer for many things It can cause cracking.
2) Ebony does not like a sudden change in moisture content. It does not tolerate soaking it in anything. Even wiping the surface with alcohol or acetone too heavily can cause surface crazing.
3) Any heat will cause internal stress. If buffed hard, it will shine like glass, and then a day or two later it will be covered with spider web cracks.
4) Use on sharp tools and saw blades, and sharp fresh abrasives. Go slow in sawing and in sanding. If it builds up heat it will usually ruin the piece.
5) Ebony needs to dry for many years, even decades, to become stable. Most online ebony is far too fresh to use. It often ones covered in wax to "protect" it. When the wax is removed, cracks form soon due to the fact that the wood is still pretty green inside.

Ebony is more trouble that it is worth for many people. African blackwood is a more popular substitute.

When someone points out that ebony was used on folders, musical instruments, and other things for centuries I reply that is was properly cured and aged before those things were done. Also, that was ebony that had grown for as much as a century before harvest. Much modern ebony is farmed and forced to grow as fast as possible, then harvested at a much younger age than in the past.
Click to expand...
You are like a library, in every post by you there is something I havent read or heard yet. Thanks!
 
FredyCro said:
Is that really gabon ebony? How and when did it crack, what was your procedure?

I have a lot of african blackwood that looks similiar to this and it will sink in water without stabilizing. With normal (home) set up you will not be able to stabilize and/or there will be no gains from stabilizing dense/oily tropical wood.
Click to expand...

Well, it was advertised as such. It's my first time working with it.

I kept it under vacuum for about 4 days, and let it sit another 8. I cured it in the oven overnight at 200F. It cracked as it cooled when I took it out of the oven.

Stacy E. Apelt - Bladesmith said:
Some issues to know abut with ebony:
1) IMHO, Cactus Juice isn't a good stabilizer for many things It can cause cracking.
2) Ebony does not like a sudden change in moisture content. It does not tolerate soaking it in anything. Even wiping the surface with alcohol or acetone too heavily can cause surface crazing.
3) Any heat will cause internal stress. If buffed hard, it will shine like glass, and then a day or two later it will be covered with spider web cracks.
4) Use on sharp tools and saw blades, and sharp fresh abrasives. Go slow in sawing and in sanding. If it builds up heat it will usually ruin the piece.
5) Ebony needs to dry for many years, even decades, to become stable. Most online ebony is far too fresh to use. It often ones covered in wax to "protect" it. When the wax is removed, cracks form soon due to the fact that the wood is still pretty green inside.

Ebony is more trouble that it is worth for many people. African blackwood is a more popular substitute.

When someone points out that ebony was used on folders, musical instruments, and other things for centuries I reply that is was properly cured and aged before those things were done. Also, that was ebony that had grown for as much as a century before harvest. Much modern ebony is farmed and forced to grow as fast as possible, then harvested at a much younger age than in the past.
Click to expand...

Thanks for all the info. Honestly, I doubt I will bother with it again!
 
If you do want to use ebony check the moisture content 1st. You want it to be around 10%. If it is higher than that put it on a shelf out of direct light for a few years then check the moisture content again. DO NOT TRY TO SPEED UP THE DRYING.
Best ebony will come from a deceased woodworker estate because it has probably dried for a couple decades or more.
If you have dry (under 10% mc) ebony send it to k&g for stabilizing. They have a thinner formula that they use for ebony and rosewood. With ebony the stabilizing will darken the wood a bit. That is a good thing with ebony.
 
The old knife companies that used ebony used stuff from old growth trees that were cut and aged for a very long time. Then the logs were sawn and aged for a very long time. I have a late 1800's C.F. Wolfertz & Co. two blade jack (folder) with ebony scales. It has been used hard for over a century and only has one small crack at the butt pin. It has never been refinished/oiled/waxed/varnished and the ebony has a lovely shine from hand wear.
 
when ends are exposed, wood will check along its entire length. The lesson in this case is that you can cut the scale parts to size wet and seal the ends and probably not have any issues, but if you have small very dense wood that's wet and the ends are unsealed, the chance of checking is high.

If you want to stabilize ebony in the future, see what wood turners, too. Pencils are stabilized with wax, which is probably delivered with something like mineral spirits (dissolving paraffin wax in mineral spirits, for example, allows the mix to soak into the wood leaving the wax behind when the mineral spirits dissolve). That affects ability to glue, though.
 
Well, in this case I can't cut it down, because it's for a hidden tang knife and thus was already cut down to size. But you are saying I should have sealed the ends when I treated it? I just worry that doing that wouldn't allow the stabilizing resin to penetrate.

I doubt I will use it again, but I do have one piece left that I haven't stabilized. I just planned on using it without stabilizing, at this point.
 
Mobius1 said:
Well, in this case I can't cut it down, because it's for a hidden tang knife and thus was already cut down to size. But you are saying I should have sealed the ends when I treated it? I just worry that doing that wouldn't allow the stabilizing resin to penetrate.

I doubt I will use it again, but I do have one piece left that I haven't stabilized. I just planned on using it without stabilizing, at this point.
Click to expand...

I'm not sure that it needs to be stabilized if it's more than a year or two old and cut small with the ends sealed. Turners tend to come up with processes for microwaving or alcohol or some combination (I don't do that) with ebony, and if there is concern about stability, you can continue to dry it further than ambient, but I've found it good as long as the ends are sealed.

I don't make knife handles, but rather tool handles and guitars, so my needs may be different (in terms of the need for stabilizing to get a polish on a handle or something). Ebony polishes to a grand level coming off of a lathe for a tool handle, like it already has finish on it, but I haven't belt ground a handle, etc.

All that said, if wood cracks with the ends exposed, it will generally crack all over because the ends are letting moisture out (sometimes leaves people feeling like the moisture is leaving from the sides when the sides are cracking, but that's only the case if the grain actually runs out on the sides).

It's nice to get old ebony and rosewood as some are mentioning above, but I also find a high incidence of bug holes in stuff like that. I had a billet of bois de rose at one point years ago when I was a beginner that i thought was cocobolo. It was more than 50 years old and the size of a lunch box (this is unobtainable at any price now) and got it cheap. However, what would be an almost priceless piece of wood now was ruined by having a bunch of bug holes in it. They could be "features" if you're artistic and want to fill them with colored resin or some such thing, but I used it to make an infill plane and that's a no-go there.
 
A while back, Don and my pile of spalting persimmon logs got invaded by termites. I quickly cut it up into good size blocks and put it in a steel barrel with an airtight lid. After about a year I opened it and dumped it all out. Some cleanup and re-cutting showed that there were termite tunnels all through it. Most of the tunnels were packed tight with wood dust and termite poop. I dried it for another year, and because the saplting was really nice, I sent it to K&G for stabilizing. When it came back the stabilizing resin had filled the wood/poop in the tunnels and made them attractive looking and dark. It had a look like large scale Masur Birch. I use it on big knives for a rustic look..
 
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