Ebony blank cracking

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socdad

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I've run into a problem with an ebony blank cracking a couple weeks after completing the pen. This is on a Navigator kit w/ CA finish. Any hints on how to avoid the problem?
 
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DotDoc

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I have had several crack on me. I also have one that is just fine after 6 months. I don't understand what is causeing the problem but if you find out pls post. I do rmember someone posting that ebony can't take temp changes very well.
 

aggromere

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Ebony is prone to cracking, I really don't know why. I have made ebony pens that looked perfect and a couple weeks later or month later they had cracks. I have made a few that so far no cracks. But it is a common complaint about ebony.

The only suggestion I can think of is drill it a little at a time so that it never gets even slightly hot. Let it sit for a few hours or a day before gluing the tube and when you turn do so with light passes so you get no heat buildup. A real pain, and I'm not sure that will keep them from cracking. The wood is so dense I don't think trying to soak it in thin CA would help, but it might, I never tried it.

Good luck.

Exotic Blanks sells an alternative ebony that is man made and looks pretty good.

I have some fairly old pool cues with ebony butts that have never cracked, but they don't have holes drilled all the way through the center either.
 

KenV

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Only wood more crack prone than ebony is Snakewood -- that which has cracked and that which will crack - One develops skill in working/restoring these woods if one is using them.

Love ebony and snakewood and plan on repair and refinish.
 

jttheclockman

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I've run into a problem with an ebony blank cracking a couple weeks after completing the pen. This is on a Navigator kit w/ CA finish. Any hints on how to avoid the problem?


How are you gluing in the tubes??? I would use epoxy. With epoxy you have a better chance of getting complete coverage and it will get in all the nooks. Also as mentioned after drilling let the blank sit so it will now acclimate to the surround temp. Good luck. There are alternatives that look just as good especially if you are just putting a CA finish on it. If just friction polishing then that is a different story. Just because wood is cut drilled and finished does not mean it is dead. It will move and different spieceies have different rates of movement. When you lock wood to a metal tube it does not have the chance to expand or contract however small this movement is. That is why I frown on wood pens. I make a few but the thinner you make the blank the more problems arise. That is my 2¢
 

BRobbins629

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You can minimize (but not eliminate) the chance of cracking with some or all of the following:

1) Drill very slowly with very sharp bits. Do not let the wood heat up. Some do this over a hour or more per blank.

2) After drilling, test the fit of the tube. If it is tight, ream it our with a file until it is loose. Let it sit for at least a day and check again. If it is tight, ream it again until loose. Repeat process until it doesn't shrink any more.

3) Now glue tube to blank, turn and finish - again with sharp tools and do not let the material get hot.

4) Before inserting components in pen, either ream out the tube or sand/file down the parts so they are a slip fit in the tube rather than a press fit. Glue them in rather than pressing them in which will expand the tube and stress the wood.
 

socdad

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Thanks for all the info ... sounds like this will be several pens for my self. (and very understanding friends)
 

Rifleman1776

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Ebony is shipped fresh (wet) from it's source countries.
It is then milled and sold as blanks or just sold in chunks. There is no time for it to dry.
If you buy your ebony then put away for several years before trying to make into pens, or anything else, then the cracking problems will be minimal to none.
Who wants to wait?
Don't wait? Expect cracking.
 

penmanship

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what I found works for me is to turn the blank(s) proud of the bushings then leave them alone for about a week. They usually do what they're gonna do by then.

Get them back on the lathe, finish turning them & sand, polish, & finish as normal......so far it's worked for me.

Good luck with them,
Tim
 

ThomJ

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I've gone to blackwood. I made a snakewood pen 2 years ago & its fine still, but have made others that cracked in a week
 

its_virgil

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Wichita Falls, TX, USA.
Ebony is a cracker. The problem can be avoided by not using ebony. I've stopped using it. African blackwood is a much better choice. We have been conditioned to think that ebony is some special exotic expensive wood when in reality it is no more special, rare or exotic than any other rare, exotic, special wood. I hear some woods extolled as being rare but I've never had any problem purchasing those woods...which ever they are. There are too many other nice exotic "rare" woods to use that do not crack to use those that do.
Do a good turn daily!
Don

I've run into a problem with an ebony blank cracking a couple weeks after completing the pen. This is on a Navigator kit w/ CA finish. Any hints on how to avoid the problem?
 

Wayne

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Problem Cracking

Some woods (Ebony, Pink Ivory & Snakewood) are more prone to cracking after turning. These woods are more unstable than most and rather than taking the stress they crack to release the stresses. I've been successful with a method that I got from this forum with some adaptations.

- Drill your blanks as normal.
- Coat the inside of the blanks with thin CA.
- Let the blanks set aside for at least a week.
- After one week, re-drill them with a hand drill and the same drill bit. You'll notice some material is removed.
- Coat the insides of the blanks again.
- Set aside for another week.
- Re-drill as beforehand.
- Let the blank acclimate to the room temperature.
- I then use thick CA to glue the tubes in.

I've been quite successful with these blanks.

Some additional ideas listed below have been seen on this forum.
Use a flexible CA, microwaving and even boiling the blanks have been mentioned. Try searching the forums for snakewood or ebony and you should find other options.
 
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