Spalted maple "stabilization"

[JDaniels]

I'm not sure if I am using the term stabilization correctly, but it seems to fit the 1st problem. I have some spalted wood that I make pens out of but I am not quite sure how to keep it from splitting off of the tube. My tools are sharp.

Also, the wood is super brittle and the varying densities created by the spalting causes some areas to be turned "deeper" than other area.

Would pentacryl help with these problems or do you have some other solutions. I could CA as I go to keep it from splitting off the tube but I doubt that it would help with the other problem. I'm hoping that the pentacryl would help with both. Any ideas?

Thanks,
Jay

 

[MichaelMouse]

As you can see from the re-turned maple bowl, my answer is to cut and run from punky wood problems.

Pentacryl is a water-borne "bulking" agent as near as I can figure. On a long grain configuration you'll not get much penetration without heroic measures, so it may not be practical to paint, wait and turn in several cycles. If you already had the turning close to final dimension, you could try a soak and dry cycle to see how deep it gets.

There are other bulking plastics around the shop like PVA in your glue bottle, and the delignified white seems to pull in more than its share, so there may be a cheap solution (50/50) at hand for bulking out the punk.

 

[Bill Grumbine]

Jay, I have had great success using Minwax Wood Hardener to help with spalted wood. Back in the early 90s I was making a lot of pens, and I made a spalted maple one. People went nuts for it and I immediately got a bunch of orders. I started turning a lot of them, but the failure rate was over 90%. I saw the hardener in an ad and gave it a try. I cut and drilled all my blanks, making them just a little oversized for good measure (ha ha) and put them in a mason jar full of the wood hardener. After they all sank to the bottom, I pulled them out, drained them, and let them dry for a few days. The rate of failure dropped to about 2%. I still use the stuff for larger pieces, and just posted one the other day.

This piece of spalted maple burl was extremely punky, but the hardener saved the day for me. It is a little rough on the inside, but no one really cares about that except other turners. So you see, you can cut, but you don't have to run.

 

[seafoam]

There is spalted, and then there is punky - the wood has not only changed color, it is now into some major decay.

Pentacryl I believe is used to stabilise green wood (stops it cracking), so I doubt it will help.

I use acrylic floor polish on larger items like weedpots if the spalting has gone at all soft. I'm not sure how well it would stand up to a lot of handling on a pen. Your best bet is probably one of the two part epoxy products designed specifically to harden rotted wood.

I'm not sure how uniformly hard this will make your wood. Be very careful sanding. You may have to sand with the lathe stopped, by hand, with the grain.

 

[seafoam]

I also meant to mention that some woods spalt in a more robust way than others. Elm in my experience tends to rot very easily, creating large grey areas and less pretty black lines. Beech I would rate as excellent, yellow birch as good. I have never come across a lot of spalting in maple, though it does suffer from blue stain.

 

[mr bill]

The "water thin" CA glue will work great on punky and spalted maple. Especially on smaller things like pens. It becomes too expensive on larger pieces. A lighter touch (shearing) with your tool might help also.

MB

 

[DMcIvor]

spalted maple

I picked up a technique from somewhere on the web that is working pretty well for me.

Head down to the hardware store and buy a bottle of white glue--the cheaper the better. Dilute it 50:50 with water and soak your roughed blank in this solution (I use a zip-lock or garbage bag, whatever is required to accommodate the piece). I've been soaking pieces about 24 hours, turning them occasionally to assure the glue solution has a good chance to saturate the whole piece. After 24 hrs., remove the piece from the glue solution and let it dry another 12-24 hrs.

This approach has the benefit of being less expensive and with no obnoxious fumes, two advantages over CA.

The glue solution penetrates the spalted/punky wood and when hardened allows for a decent finishing cut and sanding.

I'm sure depth of penetration depends on a number of variables, but 1/2" seems certain, while an 1" gets a bit tenuous.

Don

 

[pencheff]

The glue solution penetrates the spalted/punky wood and when hardened allows for a decent finishing cut and sanding.

How does the glue-soak technique affect the finish? Will BLO or other oils still soak into the wood after this procedure?

I have some spalted-and-worse box elder bowl blanks that are going to need some TLC along these lines in order to be usable.

 

[DMcIvor]

glue soak and finish

How does the glue-soak technique affect the finish? Will BLO or other oils still soak into the wood after this procedure?

I have only tried this technique with a few finishes (walnut oil, wax, tung oil, Danish oil) so I can't claim it won't interact adversely with something out there. For reasons I can't explain, the glue soak doesn't seem to have any effect on any of the oil finishes I've used. Except that compared to untreated spalted wood you get a good clean surface!

All I can conclude is that the glue does not create an impermeable barrier. Oil seems to penetrate just fine, so I expect BLO would perform well.

Don

 

[MichaelMouse]

Wood works with water and oil differently, as we know, but anyone who's ever found an ugly white spot from neglected squeeze-out on a flat project can tell you oil and plastic don't mix in this formulation. The point of the soak is that things more or less even out, with the wood accepting oil about like the second coat in unsoaked. Spot applications will produce spotty results.

"Bulking" agents is what the FPL calls them. Water solutions or emulsions of plastics. Acetate, acrylic and vinyl have all been mentioned in the thread. As to how much or how far they penetrate, look at your sandpaper. They all have fairly low melting points.