The Trouble with Ebony

[Sonya R]

I'm fairly new to the world of penturning and woodworking, in general. I'm trying to make a pen out of ebony, but no sooner do I get it made than it develops a crack. I'll tell you how I've worked it, and maybe you have some suggestions on how to do this differently/better to avoid the cracking. After shaping, I've sanded smooth to a 600 grit, added a coat of thin CA, followed by four - sometimes five - coats of medium CA. Lightly sanded back to a 1500 grit to give it a matte finish. I'm certain that I didn't sand back through THAT many coats of CA. Any insights? I've already checked previous posts, and about all I really get is that I'm not too far off the mark, but I'm just dealing with the nature of the beast.

 

[plantman]

Sonya; Ebony is a diffucult wood to work with in the first place when turned very thin. I don't know if this is the answer you are looking for or not, but this is how I treat my Ebony pens or turnings. On the pens, after I drill them, I coat the inside with thin CA then redrill. Make sure the blank has cooled off before glueing in the tubes. I have never used CA finish on any Ebony items I have made, I always use 5-6 coats of buffing polish in three different grades. I have faucet handles I have made for the bathrooms almost 20 years ago that have never cracked. Jim S

 

[tim self]

The only thing you didn't mention is heat. How WARM is the wood getting. It doesn't stand up well to it while sanding. It's probably the most unforgiving of all the woods in that aspect. Well that and snake wood.

 

[Sonya R]

The wood is getting warm to the touch, but never hot. I thought heat might be playing a factor, but the cracking is happening several hours after turning and sealing. Do you think heat might still be a factor?

 

[BRobbins629]

There are a few things that you can do to minimize the chances of cracking with woods like ebony. Not foolproof, but definitely increases your chances.

1) Drill with sharp bits and keep cool
2) After drilling and before gluing to tube, let it sit for a couple of days or even a week to stabilize to its new shape without the constraints of glue and tube. If it doesn't fit the tube because it changed shape, take a round file and file the inside of the wood until it fits again. Repeat if necessary.
3) Before assembling the pen, either file out the inside of the tube or sand off some of the fittings so they are now a slip fit instead of a press fit. Glue the tube to the fittings rather than pressing them in. When you press them in, the brass tube stretches and puts considerable force on the wood. Woods like ebony don't like stress.

 

[Sonya R]

I wonder if I'm battling a moisture content issue, and if I am how to deal with it? I say that because the stock from which I cut the blanks was very well coated in wax when I purchased it, but within 8 hours of cutting, it too was cracking - without any shaping or introduction or glue or other stresses. (I doused the exposed ends in a thick layer of thin CA to prevent further damage.) This said, wouldn't the inside of the blank, now exposed to air, start cracking as it stablizes to its new shape? If I am dealing with a moisture content issue, how to deal with it?

 

[PenMan1]

Sonya:
I'd just make something else. Ebony isn't all that special, it doesn't look all that great (even with masterful finishing), AND it may be today, it may be 6 months from now, BUT EBONY IS GOING TO CRACK AT SOME POINT.

Quit beating yourself up! It's just ebony....IMHO, it AIN'T special, it Ain't all that pretty and it's a P.I.T.A to work. There IS a reason they make alternate Ebony.

 

[plantman]

Sonya; I agree with PenMan1, switch to African Blackwood. Its hard to tell the difference between it and Ebony. Look up my new thread Zulu Warrior, I have a pen in Blackwood there. Jim S

 

[PenMan1]

Another reason to switch to African blackwoid is because you can quit looking at the soles of your shoes to see if you stepped in something.

Turned Ebony ranks right up there on "pee youuuu" scale with Desert Iron Wood. IMHO, the results of DIW (desert iron wood) IS WORTH the sensory assault, Ebony is NOT!

Respectfully submitted.

 

[76winger]

I've made several pens with Ebony and as yet haven't had any problems with them (that's been reported anyway). Most all of them however have been comfort pens, where the thickness is greater than slims and many other pens. I also, like Bruce mentioned, drilled them out slowly to keep cool and let them set for a couple weeks before gluing tubes in.

After turning and sanding, I never use CA on harder woods like Ebony, using Shellawax instead. This is other wax based finishes lets the wood breath instead of sealing it a plastic shell, and since the wood is REALLY hard, you don't need the protective coating on them as much.

Also, most of the ebony I've gotten has been sealed in wax as well. And some of it sat in the blank box for a couple years before I used it, which also allowed it to stabilize some more.

Just as a Heads-Up: Snakewood is another one prone to cracking, even more-so than Ebony, so same rules apply.

 

[76winger]

Another reason to switch to African blackwoid is because you can quit looking at the soles of your shoes to see if you stepped in something.

Turned Ebony ranks right up there on "pee youuuu" scale with Desert Iron Wood. IMHO, the results of DIW (desert iron wood) IS WORTH the sensory assault, Ebony is NOT!

Respectfully submitted.

That's interesting Andy, I never noticed any smell with the Ebony I've turned. Maybe because it had aged longer than most people let it???

 

[KenV]

I wonder if I'm battling a moisture content issue, and if I am how to deal with it? I say that because the stock from which I cut the blanks was very well coated in wax when I purchased it, but within 8 hours of cutting, it too was cracking - without any shaping or introduction or glue or other stresses. (I doused the exposed ends in a thick layer of thin CA to prevent further damage.) This said, wouldn't the inside of the blank, now exposed to air, start cracking as it stablizes to its new shape? If I am dealing with a moisture content issue, how to deal with it?

Sounds like wet wood!!!! or at least high moisture wood.

I do a fair amount of ebony -- tops for shell casing pens, (and finials) but I am using ebony that has been in my inventory uncoated for considerable time (2-4 years depending on the piece). It does move as it dries an I lose some before it gets there -- but always need little pieces for bird house ornament perches.

Moisture and movement are not your friend, and ebony takes longer to stabilize for moisture than most (except snakewood and some desert ironwood).

I like to work with it --- and dry African blackwood is very similar, and may be more black.

(had a few bowl blanks come apart while getting to a dry condition though)

 

[Sonya R]

All good feedback. Thank you all very much.

 

[sbell111]

Another reason to switch to African blackwoid is because you can quit looking at the soles of your shoes to see if you stepped in something.

Turned Ebony ranks right up there on "pee youuuu" scale with Desert Iron Wood. IMHO, the results of DIW (desert iron wood) IS WORTH the sensory assault, Ebony is NOT!

Respectfully submitted.

That's interesting Andy, I never noticed any smell with the Ebony I've turned. Maybe because it had aged longer than most people let it???

You probably have your dust control system working properly.

 

[Jgrden]

My Ebony has split. At a out door show the sun krept over the canvas and hit several pens made out of Ebony, six of them split. When I use Ebony, Epoxy is my choice, dry the Ebony in a microwave, 30 secs. X 4, and then after drilling let set for a few days. If it cracks it is easy to fill and move on.