I just cut up some silver maple that had been laying in my wood pile for a year or so. The log had some mushrooms growing on it. So I knew that the wood had to show some spalting. However, when I cut it opened, I was amazed at the amount.
I cut up several blanks for bowls and a bunch of pen and bottle stopper blanks. When I went to rough out a bowl from the big blank, I was confronted with some of the punkiest wood I've ever seen! I ended up chucking it into the wood chip pile (as you can see from the background of the photo). I was heartsick. This wood is really quite beautiful and could have been a very cool looking bowl (and for those purists in the audience: I realize that there are flat spots on the profile. I stopped before totally shaping it.)
This was yesterday. And every time I walked by that trash can, that beautiful (yet awfully punky) blank would taunt me. I finally decided to ask the group here what they thought and to see if there was some type of treatment I could use on this wood to make it "turn-able".
If I remember correctly, you can soak a punky, roughed out blank in a solution of white glue and water. I don't know the water to glue ratio, or if I have even stated it correctly. I was wondering if any one else might know. I'd like to know what kind of regimen you've used.
I've also heard of some type of liquid (maybe "Pentacryl" or "Polyall"?) that is used to stabilize punky wood. I'd like to hear from those of you that have used it.
>Hello,Ive been working with some maple just like that and also some spalted basswood that's really bad but to pretty to throw away.What I've been using is lacquer.I found some old lacquer and really slobbered it on and let harden.I've also thinned it out and soaked the piece in it.I rough turn it as far as I dare and then start with the lacquer.Good luck!
I agree with Steve..."Life is too short to turn @!#%&* wood" I think it was John Jordan who said something to that affect.
I have wasted so much time trying to work punky wood that the minute I see that it's too punky....I toss it off the lathe. I've tried the hardeners and the Pentacryl and all that jazz. From the looks of your picture.....I'd say this one needs to be tossed :(
Dominic, you are right about that wood needing to be saved. I might have some tips that you can put to use. First you should know that all of the things I talk about here are methods that I developed for old dried rotten wood, not on unseasoned logs, so there will be some variances for you to work out.
Almost any resin or glue will work. The ideal is to get one that has a very thin viscosity in the vehicle and one that does not set hard too fast. How hard it sets can also become a factor when later work needs to be carried out.
I have settled on an epoxy called West Systems. I use the 105 resin and 206 hardener. Then I thin it with acetone. Anything from 10% - 80% and it will still dry. What you notice is that the hardness of the set resin becomes softer as you increase the acetone. Over 50% and it is too rubbery.
The above resin is not unlike an available product called "Git-Rot" and "Cure-rot" But for your purposes the instructions that come with the proprietary products might not serve you well. They each advise that you soak or inject the liquid, and I have found that the penetration is very sporadic and poor.
What is required is a method that will fully penetrate the wood to the point that the resin has rendered solid strength to the entire wooden item. (we are often treating worm eaten chair legs) What we do is create a suction through the end grain of the item, as though it was a giant drinking straw sucking up the resin. This is achieved by setting one unsealed end of the item into a container of the resin and applying a vacuum line to the other. Sealing the parts of the item that are in free air will help. Often with a chair leg nothing more than a coat of wax is required. I have had times when a total wrap of kitchen plastic wrap was required. It is most important to seal the open end grain at the sucking end. With small articles this can often be accomplished by stretching part of an old auto inner tube over the end and attaching the vacuum hose to it with good ole duct tape. (Red Green engineering school) In the case of large logs you might want to insert the vacuum hose into a drilled hole in the log and then seal around the entire end grain.
The only drawback I see is the cost. We don't worry too much about that when saving an 18th century chair, but the volume required for a large log can quickly top $100 in resins. You might experiment with some thinned out Waterlox varnish and see if it delivers the hardness you need. It will certainly be more cost effective.
>Dom, I haven't had a lot of experience but I have used a fifty-fifty mix of white glue and water to save a punky piece. I imagine one could experiment with the proportions. I know there are many turners who get all the pretty wood they want. I have to really scrounge to get even small pieces of nice wood, so if I can save a pretty piece I give it a shot.
>I don't know how punky your wood is but in some instances I have had some success with spalted wood by soaking it in Minwax wood hardener available at your local BORG.....
>There is a product used by poolcue makers called Nelsonite. As you can tell by the link below it is also used to stablize knife handles. I've have only used it once but it did a great job stabilizing a very punky vase.
I have been experimenting with using shellac to harden soft wood. It worked pretty well with some desiccated big-leaf maple burl that I had. Since alcohol is the solvent, it seems to penetrate pretty well. Another plus is that it dries quickly. If you decide to try it, I'd be interested in hearing how it goes.
I use this stuff called "rotted wood stabilizer" from the local Lowes store. It's water thin, brush on or soak it until the wood won't hold any more. It works great, but stinks to the high heavens; wear a respirator. Actually, it smells just like PVC cleaner. Dries very fast, should be ready to turn over night. Whatever meathod you use, let us know how it turns out.
I used thinned lacquer. I put equal parts of lacquer thinner and lacquer together and brush it on. I keep putting it on the areas that soak it up. It will actually penetrate all the way through the walls of a bowl. If firms up the soft wood really nice. Of course it isn't compatible with all finishes but I use lacquer on most of mine anyway.
>I've been thinking about impregnating wood with witches brew or whatever under slight vacuum with a hand squeezed brake line bleeder. I figger flaring 1/4" tubing and soldering it to a jelly jar lid for the connection with maybe 'nother jar in line as a trap. The brake line bleeder runs about $30.
I think I would give that wood one more chance. But the odds of success are not the best, so I wouldn't sink a lot of money into the attempt. That's why I would suggest the glue/water method. A big bottle of carpenters glue dosen't cost that much.
Put it back on the lathe and shape it as much as possible. Then wrap the outside in duck tape and clear out some of the wood on the inside. Take the tape off and drop the blank in a vat with a 50/50 solution of glue and water, and soak overnight. Then let it dry for a couple of days.
This really should make a huge difference. If not, then chuck it in the garbage!
For the pen blanks and bottle stopper blanks, I would send them to Bill Baumbeck and have him stabilize them for you, but that's just me! ;-) Home stabilizing has been doing well for some of the people over at the IAP. They use polyurethane to cover the blanks in a jar, then pull a vacuum to encourage penetration of the poly.
I've got one nice piece of spalted alder left that looks a bit like your piece. I can't decide on a bowl or a hollowform, but it's patiently waiting for me to make up my mind. ;-)
>I think there is a place in Iowa that "stabalizes" wood.It is expensive.You could do the same yourself,but it is a bit to get set up--but once you have then you can stabalize as well,and also be able to take some woods that are not as good to turn and experiment.I am thinking of softer woods and palm as a good example.
The set up is to make an air tight container and draw the moisture out of the wood.Totaly dry.Then to submerge the wood in a mixture of half and half,mineral spirits and hardener such as a polyurathane.When submirged--apply vacumn again to infiltrate the wood pores.Then remove and let dry.Usually a month for the whole process.I have gotten this information from knifemakers.They use this to harden the handles.Gary
As far as economy, I believe the thinned lacquer and/or white glue method to be the direction to head. With a minimal cash expenditure, I can see how they will work.
However, I've been brainstorming with some of you off-line about using a vacuum to "pull" a hardener into the wood. I've read some articles about this and believe that I'd like to give it a try. I have a vacuum pump, and some spare fittings. All I need is a suitable "vacuum chamber". I've been thinking of an old pressure cooker. Heck, there are garage sales and flea markets all over the place. I could probably pick one up for about $5. I have a whole boat load of pen blanks that I'd love to have stabilized.
And some of you were kind enough to recommend sources for sending wood out to be stabilized. I actually may try this out if I can get a chance.
>into the wood. ...All I need is a suitable "vacuum chamber".
Dominic,
Some of us were discussing this locally this weekend. I mentioned how in the mid '70's I ran a small metallography lab where I analyzed sections from nuclear reactor elements. I used a small vacuum chamber to pull epoxy into a bundle of samples and into the pores of a permeable powdered uranium core. I placed the samples in a small ring container made for such things, "flooded" the samples with epoxy, then pulled a vacuum until no more bubbles were formed. This took some time even for small samples, made worse since the epoxy was thick. Then the pump was turned off and the pressure returned normal. This pulled epoxy deep inside the samples which I then ground and polished.
Our vacuum chamber was a simple plexiglass dome, perhaps 1/8" thick, with a rubber seal at the base. It sat on a steel plate. The hemispherical shape prevented collapse. At another lab we had both rectangular and cylindrical vacuum chambers. Depending on the vacuum required (this was for spinning magnetically-levitated motors to extremely high speed), the rectangular chambers had to be pretty thick to be strong enough. The cylindrical chambers are much easier to make since the cylinder resists collapsing.
I have a large plastic dome I bought from Edmond Scientific. Something like that would probably make a good vacuum chamber although it is parabolic rather than sperical. And not long ago I did a web search for plastic globes and found some industrial suppliers that sold spheres and hemispheres. A spherical shape would be the strongest.
I actually have a cylindrical "vacuum chamber" in the other room that would be easy to duplicate. It's an underwater video camera housing made from an 8" plastic cylinder about 1/4" thick capped with two 1" thick slabs of plexiglass and sealed with rubber x-rings (similar to o-rings).
If you make your own chamber AND it is large AND you intend on pulling a stong vacuum, you might want to stand back while testing! Vacuum is a lot safer than pressure, but it is possible, although unlikely, that some designs may implode catastrophically and scatter shards of material at high speed. What is far more likely is a leak will develop as the chamber deforms and the pressure will be equalized more slowly, but I'd still put it in a bunker or leave the room!
I can't guess how much vacuum would be needed to saturate wood so maybe you will not need a very strong chamber. Maybe a plastic bucket would be sufficient, but I would want some kind of clear window to monitor the bubbles. (Might be a problem with a pressure cooker) Of course, the larger the chamber and the stronger the vacuum the stronger the structure needs to be. If you tell me what volume you need and what vacuum level you expect, I can try asking my buddy Joe (a vacuum expert) for recomendations.
You might even get away with using a large heavy plastic or vinyl bag or sheet similar to that used in a vacuum press. It might be messy, though, and you would have to devise some way to allow the wood to be submerged in a suitable volume of liquid.
The thinner the liquid the better, of course. I do imagine that saturating very porous punky wood as you described would be FAR easier than trying stabilize by forcing a liquid into the center of a healthy piece of wood, especially a wood without open grain!
Would it be easier/cheaper to just buy a quantity of thin CA glue and let it soak into the wood? I use that for small punky areas.
I've been trying to think of ways to try a combination of both vacuum and pressure for stabilizing. First I want to pull a vacuum and hold it then when released apply pressure to force the material to penetrate.
I've been thinking of a short piece of pipe with end caps. One cap would be drilled for a 1/4" nipple that can be attached to either the vacuum pump or compressor.
In your opinion do you think this might work or am I in the process of building a bomb?
Will you be pressurized with air? Pressure with gas is a lot more dangerous than vacuum, but the danger goes up with higher pressure and as the vessel volume increases since a large tank can store a large amount of energy and is more likely to flex and rupture. If it does rupture it is a bomb. With a small volume like a pipe the danger is a lot less since it cannot store as much energy at the same pressure. However, I would still protect myself regardless of the pressure - a defect in the pipe might cause a rupture or blow the cap off the end.
I worked for a time in a laboratory where we tested large vessels. When pressurized with air, we put the vessels in a blast pit and closed the top with heavy steel plates lowered with a crane. For a small vessel, a few bricks and perhaps some plywood would probably be enough.
Note that hydro pressure (pressurizing with liquid instead of gas) is very safe since liquid does not compress and cannot store a huge amount of energy. If the vessel ruptures, the internal pressure is lowered very quickly leaking only a small amount of liquid. (We hydro tested large vessels right out in the open.) If building a gas-pressurized system you might rig up something to hydro test it to a higher pressure than the intended working pressure. Industrial gas cylinders and scuba tanks must be periodically hydro tested.
Another thing to do is add a pressure relief valve or a rupture disk. You could get the fittings and disks from an industrial supply place or from old scuba equipment. (In my younger and more foolish years we would defeat the rupture disk protection and run 5000 psi in double 80 tanks for cave diving - that was insane! Well, cave diving itself is probably insane.)
If you can build a totally hydraulic system it would be totally safe. It might be easy too - use the stabilization liquid as the hydraulic fluid. Or use a conventional oil-filled hydraulic system and isolate the stabilization fluid from the oil with a bladder of some sort (for example, put the wood and material in a heavy balloon.
If you weld you could build a vacuum/pressure chamber from something like two pieces of schedule 40 or 80 pipe, weld a cap on one end of each, and weld a heavy flange on the other end. Use a gasket and bolt the flanges together. I'd add separate valving and plumbing for the vacuum and pressure sides.
But part of me asks the question, will this work well enough to make it worthwhile? Any open pores should be forced full of liquid as the vacuum is released, doing exactly the same thing as the pressure stage. It seems to me that any value added by the pressurized stage might be better accomplished by just pulling a better vacuum at first. The pressurized stage would add a lot of complexity.
How do the professional wood stabilizers do it - can you avoid reinventing the process? (or is the process a secret?)
