Ebony - love, hate relationship

[PatrickR]

I recently made an ebony kitless pen, fully sleeved. I like it a lot and started on another one. While working on the new one I took the existing one to the shop for reference. I forgot about it being there and it was hot, upper 80s. The next day this is what i found.

I don't see cracks but am pretty sure there are some. I used Glue Boost ultra thin flex and always clean blanks well before application.
the delaminating is at 90* to each other and the area is now .10mm out of round. I will sand the finish off and see if it is salvageable.
I have said on here before that if I were selling pens I would avoid the known crack prone woods altogether and now I am close to doing the same for my own pens.
I have taken some precautions with the one I am working on, so we will see how that one goes.

 

[farmer]

I haven't had a issue with my ebony projects cracking .
My first thought is you cowboyed the wood .
The wood your using is not fully dried or cured and got used way too soon .
Normally i will use the wood I buy 6 or 7 years later.

 

[PatrickR]

I haven't had a issue with my ebony projects cracking .
My first thought is you cowboyed the wood .
The wood your using is not fully dried or cured and got used way too soon .
Normally i will use the wood I buy 6 or 7 years later.

I haven't heard the term "cowboyed" in relation to wood working before. I totally agree with you on using seasoned wood. This ebony I know was not waxed and stored cut to size in a warehouse for at least 2 years then another year in my shop. So fully dry and at equilibrium but not 6-7 years.
it could be that there are not cracks and the CA has just delaminated because of the out of round state from the temps it saw. Cracks I associate with shrinking from low humidity. This has seen high humidity and warm temps.

 

[farmer]

I haven't heard the term "cowboyed" in relation to wood working before. I totally agree with you on using seasoned wood. This ebony I know was not waxed and stored cut to size in a warehouse for at least 2 years then another year in my shop. So fully dry and at equilibrium but not 6-7 years.
it could be that there are not cracks and the CA has just delaminated because of the out of round state from the temps it saw. Cracks I associate with shrinking from low humidity. This has seen high humidity and warm temps

I suggest turning the wood round and drill it .
Leave the wood blank as large as you can keep it , As in don't cut it to its final size .
Store the wood for 90 days and then go ahead and make it into a pen .
I agree that heat and humidity could be the issue or part the issue .

 

[PatrickR]

I suggest turning the wood round and drill it .
Leave the wood blank as large as you can keep it , As in don't cut it to its final size .
Store the wood for 90 days and then go ahead and make it into a pen .
I agree that heat and humidity could be the issue or part the issue .

The one I am working on now I am using a technique from Lutherie. I've kept the wood in a box with the humidity at 50%, temp mid 70's for about 3 months. As soon as I am done with a process I put the piece in a sealed container with a 2 way humidity bag. The idea being that the wood is at the 1/2 way point in size. My local average humidity is about 47%.

 

[farmer]

The one I am working on now I am using a technique from Lutherie. I've kept the wood in a box with the humidity at 50%, temp mid 70's for about 3 months. As soon as I am done with a process I put the piece in a sealed container with a 2 way humidity bag. The idea being that the wood is at the 1/2 way point in size. My local average humidity is about 47%.

My RH is about to 35 to 50 % .I run a swamp cooler in the summer .
Hang in there ebony is a beautiful wood .

 

[Pierre---]

I like to choose the correct specie for the job. Is it Gabon ebony (Diospyros crassiflora)?

 

[PatrickR]

I like to choose the correct specie for the job. Is it Gabon ebony (Diospyros crassiflora)?

It is an unknown Diospyros. Sold in China as Purple Sandalwood, it is neither. My research yielded very little information other than it is commonly imported there. I have examples of 7 types of Ebony plus a few Blackwoods and this one is different than the others.
I was able to chip some of the delaminated CA off in one area and did not see a crack. Maybe the flexible CA isn't so flexible.

 

[jrista]

Is it possible to get any of the CA to penetrate the wood with that ebony? Or does it only coat the surface? I had trouble with delamination when I was using CA, until I made sure to get every part of the wood surface saturated with thin CA first, so that any subsequent coats of CA were on top of that initial, penetrating coat.

I've never finished ebony in CA, though, and I know its a particularly dens and more oily wood...so, it may be that you just can't get that first penetrating coat...

 

[PatrickR]

Is it possible to get any of the CA to penetrate the wood with that ebony? Or does it only coat the surface? I had trouble with delamination when I was using CA, until I made sure to get every part of the wood surface saturated with thin CA first, so that any subsequent coats of CA were on top of that initial, penetrating coat.

I've never finished ebony in CA, though, and I know its a particularly dens and more oily wood...so, it may be that you just can't get that first penetrating coat...

Yes, this is possible. This appears to be the densest of all the ebonies that I have. It is not very oily though. I used ultra thin CA, which is sold for uses like this and did not use accelerator.
the one I'm working on now I have finished with only a penetrating coat and then polished. Time will tell. I am using a pen now with the same finish and like how it looks and feels.

 

[farmer]

You really need to know if the wood is in fact cracked or it's finish issue .

Might want to read this link .

Ideal Humidity in a Wood Shop

Indoor humidity levels correspond with wood moisture content. Here's advice on humidity control. October 26, 2012

www.woodweb.com

I copied and pasted this statement
35% Relative Humidity ~=7% wood moisture content. Perfect, or at least really close, for indoor applications in most areas. In the winter I achieve this with heat. In the summer I get it with dehumidification.

 

[PatrickR]

You really need to know if the wood is in fact cracked or it's finish issue .

Might want to read this link .

Ideal Humidity in a Wood Shop

Indoor humidity levels correspond with wood moisture content. Here's advice on humidity control. October 26, 2012

www.woodweb.com

I copied and pasted this statement
35% Relative Humidity ~=7% wood moisture content. Perfect, or at least really close, for indoor applications in most areas. In the winter I achieve this with heat. In the summer I get it with dehumidification.

I scrapped some of the CA off in the affected areas and no signs of cracks. Apparently the finish couldn't take the change and/or it was not fully adhered.
I wish I had the ability to work in a controlled environment. where i live the indoor humidity (forced air hvac) varies from 10% in the winter to 30+ in the summer with ac and the yearly average is 58.8%
i have Hodleys book and will pull it out. My approach with woodworking has always been to build to allow movement but this isn't possible with pens.

 

[farmer]

If the wood isn't cracked then its the heat that caused the finish to fail ?
Or the finish is sub par and cant handle a little heat ?
At this time I am thinking the CA finish is the main issue and it only took a little heat to make the finish fail .

It's better this happened in your garage then is your customers car ..........
If the finish can't handle a hot garage that means allot your pens finishes are going to be prone to failing .

I have seen CA finishes bubble and delaminate on the more dense and oilier woods .
But I have experienced allot of issues working/using CA for a finish .
For me I was never that happy using CA for finish .
I was having to redo allot of my work .
I switched to others finished.

You might consider trying UV finish like Solarez
The brass tube and the wood both move when it goes through temp changes . wood will move more if it has high moisture content .

 

[farmer]

PS if the wood is moving that much it would of separated between the segments

 

[PatrickR]

If the wood isn't cracked then its the heat that caused the finish to fail ?
Or the finish is sub par and cant handle a little heat ?
At this time I am thinking the CA finish is the main issue and it only took a little heat to make the finish fail .

It's better this happened in your garage then is your customers car ..........
If the finish can't handle a hot garage that means allot your pens finishes are going to be prone to failing .

I have seen CA finishes bubble and delaminate on the more dense and oilier woods .
But I have experienced allot of issues working/using CA for a finish .
For me I was never that happy using CA for finish .
I was having to redo allot of my work .
I switched to others finished.

You might consider trying UV finish like Solarez
The brass tube and the wood both move when it goes through temp changes . wood will move more if it has high moisture content .

Thanks. I have some uv resin that I've been using to dome finials with that works very well. I will do some experimenting with it.