This was written as a message to Lou, but I am posting it here because there might be something of value for others. I am hoping that others will share their experiences with Ebony, Snakes, and cracks.
I was looking at Lou's Snakewood pen and how it was finished, and that started me thinking. That can be dangerous indeed.
A lot of people have a lot of problems with cracking in Ebony and Snakewood. While I have almost no experience with Snakewood, I have used a lot of Ebony, and cracking has never been a problem.
I have always thought that one of the problems is that these very dense woods were being used at too high a moisture content. In an effort to sell wood, there is no time for adequate drying between harvesting their being placed on the store shelves. I have been using "Ebony" that came with a shipment of lumber from Kenya in 1960, so it being too high a moisture content is not a problem.
Another problem might be the species. What was called Ebony in 1960 is now called African Blackwood, and the stuff being sold as Ebony (Gabon) was used for skids under pallets and shipping crates on the docks of East Africa at that time.
However, my supply of old Ebony has been running out and I have used a lot of the Gabon wood in the past few years. Cracking has been the exception rather than the rule, and I am still doing the same things that I have always done with Ebony, regardless of its source.
I have been looking at what I do with the wood, to see if I do anything different. Here is a list of the thing that I do that might be different.
First, I always cut my own pen blanks from lumber stock because I think this can be the location of the first cause of cracking later. I inspect the wood closely for hairline cracks before purchase. Using a little wooden mallet and checking it for sound, just like the instrument makers, is a good thing. This means no mail order wood.
I cut the wood on a bandsaw, rather than a tablesaw. The thinner kerf causes less heat and stress in the wood.
Drill the wood with an oversized drill, and DO NOT let it get hot. Finger hot is 125F and anything over this is too hot. A sharp drill at 1200 RPM, and an air hose to blow out the chips frequently is what works for me. If the wood ever starts to get too hot to touch, I let it sit and return to room temperature.
The brass tubes are glued in with Polyurethane because the foaming glue gives 100% support to the wood, and it is spongy enough to allow for some wood movement. I think both are essential.
Now comes what I am thinking might be the most important part. After turning and rough sanding, I wet sand the wood using 1-K Kerosene as the lubricant. I think that one of the problems with cracking is that much of the essential oil in the wood is lost from the heat of sanding. Using the Kerosene makes sure that there is plenty of oil in the wood, and the residual insures that there is oil in the wood. I have even wiped the wood with Mineral Oil to make sure there is plenty of oil in the wood.
Many penmakers advocate liberally wiping the wood with lacquer thinner to remove the oil before finishing, and I think this is the wrong direction to be going. When doing this, we are changing the nature of the wood by removing an essential ingredient of the wood, the oils, and then wondering why it cracks.
The oil in the wood means that not all finishes are suitable. Volatile solvent finishes, shellac and lacquer, are going in the wrong direction because we want to keep the oils in the wood, and not drive them out. Waterbornes won't stick to the wood because of the oils.
A bare wood finish that is polished to 12,000 Micro Mesh may be as good as it gets. A coat of wax as Lou did on his Snakewood pen with the TSW would be a good choice to add some gloss to the wood and protect it. Wax is a lubricant and may add something to the wood. At best, it does nothing to disturb the natural oils in the wood, and I think this is essential to the long term stability.
An oil/varnish finish is about the best thing we can put on the wood. It isn't fast, but it isn't brittle, and it is a durable finish. Waterlox would be a good choice because it contains no polyurethane resins. Polyurethanes become too brittle with age, and that too is going in the wrong direction with a wood that is already brittle by itself. We should be using a more flexible finish.
The oils in the wood insure that it will have a softer gloss, but it is better to sacrifice some of the gloss than have every pen crack within a year.
I hope there might be something in all of this that might be useful.
I was looking at Lou's Snakewood pen and how it was finished, and that started me thinking. That can be dangerous indeed.
A lot of people have a lot of problems with cracking in Ebony and Snakewood. While I have almost no experience with Snakewood, I have used a lot of Ebony, and cracking has never been a problem.
I have always thought that one of the problems is that these very dense woods were being used at too high a moisture content. In an effort to sell wood, there is no time for adequate drying between harvesting their being placed on the store shelves. I have been using "Ebony" that came with a shipment of lumber from Kenya in 1960, so it being too high a moisture content is not a problem.
Another problem might be the species. What was called Ebony in 1960 is now called African Blackwood, and the stuff being sold as Ebony (Gabon) was used for skids under pallets and shipping crates on the docks of East Africa at that time.
However, my supply of old Ebony has been running out and I have used a lot of the Gabon wood in the past few years. Cracking has been the exception rather than the rule, and I am still doing the same things that I have always done with Ebony, regardless of its source.
I have been looking at what I do with the wood, to see if I do anything different. Here is a list of the thing that I do that might be different.
First, I always cut my own pen blanks from lumber stock because I think this can be the location of the first cause of cracking later. I inspect the wood closely for hairline cracks before purchase. Using a little wooden mallet and checking it for sound, just like the instrument makers, is a good thing. This means no mail order wood.
I cut the wood on a bandsaw, rather than a tablesaw. The thinner kerf causes less heat and stress in the wood.
Drill the wood with an oversized drill, and DO NOT let it get hot. Finger hot is 125F and anything over this is too hot. A sharp drill at 1200 RPM, and an air hose to blow out the chips frequently is what works for me. If the wood ever starts to get too hot to touch, I let it sit and return to room temperature.
The brass tubes are glued in with Polyurethane because the foaming glue gives 100% support to the wood, and it is spongy enough to allow for some wood movement. I think both are essential.
Now comes what I am thinking might be the most important part. After turning and rough sanding, I wet sand the wood using 1-K Kerosene as the lubricant. I think that one of the problems with cracking is that much of the essential oil in the wood is lost from the heat of sanding. Using the Kerosene makes sure that there is plenty of oil in the wood, and the residual insures that there is oil in the wood. I have even wiped the wood with Mineral Oil to make sure there is plenty of oil in the wood.
Many penmakers advocate liberally wiping the wood with lacquer thinner to remove the oil before finishing, and I think this is the wrong direction to be going. When doing this, we are changing the nature of the wood by removing an essential ingredient of the wood, the oils, and then wondering why it cracks.
The oil in the wood means that not all finishes are suitable. Volatile solvent finishes, shellac and lacquer, are going in the wrong direction because we want to keep the oils in the wood, and not drive them out. Waterbornes won't stick to the wood because of the oils.
A bare wood finish that is polished to 12,000 Micro Mesh may be as good as it gets. A coat of wax as Lou did on his Snakewood pen with the TSW would be a good choice to add some gloss to the wood and protect it. Wax is a lubricant and may add something to the wood. At best, it does nothing to disturb the natural oils in the wood, and I think this is essential to the long term stability.
An oil/varnish finish is about the best thing we can put on the wood. It isn't fast, but it isn't brittle, and it is a durable finish. Waterlox would be a good choice because it contains no polyurethane resins. Polyurethanes become too brittle with age, and that too is going in the wrong direction with a wood that is already brittle by itself. We should be using a more flexible finish.
The oils in the wood insure that it will have a softer gloss, but it is better to sacrifice some of the gloss than have every pen crack within a year.
I hope there might be something in all of this that might be useful.
][
