Black streaks when sanding spalted wood

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Sfolivier

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My friends love spalted maple and I've found myself making a pretty large number of Junior Gentlemen II with this material lately. Some of my blanks are nice but so spalted that they are difficult to sand cleanly. I seems to make black dust out of the spalt lines which in turn settles into the more porous area of the blanks. I have tried the following things:

- Not sand :D Being so clean with the skew that no sanding is required. I managed to get a very clean glassy finish with a razor sharp skew but there are still small shape imperfections. It's not that the pen isn't smooth, it's more that it's not streamlined to a perfectly regular curve.

- Thin CA. Works fine but I don't really like CA finishes, I'd like to use my usual regimen of EEE cream and Enduro. Furthermore it's difficult to put enough CA glues to really immobilize the black color while sanding. It seems not too sink too much into the deposits.

- Epoxy stabilization (CPES or Clear Penetrating Epoxy Sealant). Doesn't seem to work too much for color although it makes the worst parts of the blank sounder.

Any idea? I'd like to keep the "white" parts of my blank clean.

Thanks!
 
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Have you tried stabilizing the blank with Minwax Wood Hardener first? I have had the same problem with CA making the spalt bleed into the wood. It did not seem as bad after I stabilized MWH. I"ll have to keep an eye on this to see what the experts say.
 
What people call spalt is rot. The wood is breaking down on it's return to nature.

Normally spalted wood is stabilized. This is a commercial operation and basically, resin is forced in under pressure.
 
I believe that the Minwax is easier to use and enters the wood tissues better than epoxy. I base my opinion on the fact that the Minwax is much thinner than the epoxy. I have had success in keeping the spalt from spreading with the use of the Minwax. I just predrill my spalted blanks and then soak them over night in a large jar making sure the blanks are completely covered with the Minwax material. Pull'em out, let them drain, dry, then re-drill if necessary, mount the tubes and then get to turning. :D
 
Are you sure the black isn't coming off your bushings as you sand? On a lot of porous woods this sanding dust from the bushings will deposit in your blank. You may need to be very careful not to sand the bushings.
 
you might try using a paper towel with some d.n.a. while you are sanding use the towel on top of the blank to pick up the black dust before it gets back around to the sandpaper again and gets ground in any further.
 
Unfortunately the black color doesn't come from the bushings (I've had my share of that too so I know how to recognize it ;)). The resin I used (Smiths Warm CPES Epoxy) has the same viscosity as thin CA. I think it's actually too thin and although it makes the wood stronger, it doesn't fill any gap. At the end, I could still grind some black pigment into the stabilized but porous wood.

Maybe I'll have to send my blanks for stabilization...
 
If you decide to have them commercially stabilized

http://www.rrpwhite.com/

They are highly recommended. They have told me two of my "projects" would not be feasible - they have done one project. IF your blanks are not likely to come out well, you don't have to be disappointed - they can tell in advance. (Personally, I like that!) FWIW
 
I've had the best success keeping dark woods and bushing dust from lodging in the pores by using a sanding sealer (Thin CA or mylands) immediately after the last pass with the skew and then again between each grit until I get to using MM. I got this tip somewhere else here; use the sanding sealer like you vote, early and often.;)
 
Jason has the right idea. Seal early and seal often. Use either thin CA or a real sanding sealer like Mylands. If you use Mylands, paint it on heavily, let it set for 15-30 seconds, then wipe off the excess. Apply a second coat immediately, the same way as the first. Wait a few minutes (5, maybe 10) and you are ready to go to the next grit. BTW, you can seal with CA and still finish with Enduro (or just about any other finish).
 
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