How to use wood glue & water to stabilize

[KEW]

I have a rough-turned bowl which is real punky where a limb joins the trunk.
I decided to stabilize it with wood glue/water, but I've never tried this before and would appreciate some help:

I mixed one part glue to three parts water.
The rough-turned bowl is 3/4" thick.

1) How long should I soak it?
2) Any tips for drying?

This is a natural edge bowl, so I'd like to go ahead and finish when I can.

Thanks!

 

[MichaelMouse]

Are you going to leave it 3/4 thick? Polyvinyl Acetate "stabilization" is more about substituting for lost lignin than bulking. Even there it's a topical, not a systemic. If you're going to soak, a couple weeks ought to get you some useable penetration, but then you'll have to dry the thing to get benefit of the fiber stiffening. Couple more weeks? Better to start much closer to dry and use as a topical. Brush on thick, wait 24, turn.

I'd be interested to know if the PVA goes in a quarter inch as a soak. As a topical it's replaced as you reveal unaffected areas.

 

[john lucas]

We may not be using the same words to describe what you want to do. I think of wood stabilizer as something that penetrates wood, even solid wood, to make it more stable.
It sounds like what you are wanting to do is harden the wood in the punky areas. I don't use the PVA method but I think you mix it 50/50 with white glue and water and let is sit for 24 hours. I think you have to soak it pretty good. I thought there was an article on Wood Central about it but I couldn't find it this morning.
I use clear lacquer that I thin 50/50 with lacquer thinner. It takes a bunch of applications but it penetrates really well. Sometimes you'll be brushing it on one side of the bowl and see it come out the other. I'll put on 4 or 5 applications and then let it dry overnight. I use lacquer as my final finish so compatibility has never been a problem.

 

[KEW]

Thanks for the explaination of stabilize vs harden. I had thought the two were the same. Yes, my objective is to harden the wood.
I stopped turning the bowl at 3/4", thinking that was a reasonable thickness to compromise between losing any tear-out which already existed, allowing for enough penetration, and any wood movement - hoping this would leave a solid 3/16" thick bowl inside the wood.
Sounds like I need to consider this one a learning experience. I'll let it sit 2 weeks and see what happens when I turn it down.

I'll try another piece today and use the lacquer. How close to your final surface do you turn before applying the lacquer/thinner?

If anyone has a link for wood glue hardening, I'd like to learn more about it. My shop is in the basement and I do not have very good exhaust/ventilation for eliminating fumes, so I avoid using much CA or lacquer unless the weather lets me take it outside.

Thanks!

 

[Bernie Weishapl]

I use something a little different. I mix epoxy up and mix in Denatured Alcohol until it is the consistancy of milk. I paint this on and let it dry for 24 to 36 hrs then finish turning. I use it to stablize knots and punky wood. When I started wood turning a year and a half ago a old gentleman in my home town showed me that. I also use it for bigger cracks. I mix the above mixture up then add sawdust from the sanding of the same bowl or whatever I am working on then fill the crack. I like this better than the coffee grounds and CA trick. This gentleman called it the epoxy cocktail.

 

[john lucas]

You can get farily close to the final size using the lacquer. Usually you have a lot of tearout when approaching the final size so leave it thick enough that you can turn this tearout away after the lacquer hardens. Sometimes if the wood isn't too punky you can apply the lacquer and turn immediately. The lacqeur tends to lubricate the wood and make it cut better. If it's really soft then your best bet is to let it harden.
I would think the bowl that you've just done would toughen up enough but if not try another application with more glue. Since what you just used was mostly water it will evaporate and you may be able to try another application.

 

[odie]

I use something a little different. I mix epoxy up and mix in Denatured Alcohol until it is the consistancy of milk. I paint this on and let it dry for 24 to 36 hrs then finish turning. I use it to stablize knots and punky wood. When I started wood turning a year and a half ago a old gentleman in my home town showed me that. I also use it for bigger cracks. I mix the above mixture up then add sawdust from the sanding of the same bowl or whatever I am working on then fill the crack. I like this better than the coffee grounds and CA trick. This gentleman called it the epoxy cocktail.

That's a terrific idea, Bernie......

I will be sure to give it a try. I sure hate it when I discover a crack in a bowl.....after spending a lot of effort turning it. I've also got some punky wood out in the shop right now.....as they say, just what the doctor ordered!

otis of Cologne

 

[Barry Elder]

Stabilizing punky wood

I have some Weeping Podocarpus from a big tree blown down in the 2004 hurricanes and have had trouble with tearout etc. I mixed white carpenter's glue and water 50/50 and roughed out an bowl to 5/8" and soaked it for 48 hours and took it out and dried it for probably a week. While the penetration was not miraculous, I was able to eliminate all of the tearout and have a very smooth finish due to the glue left in the wood. Being an inveterate tinkerer, I sliced some more wood to see how much I could take off before suffering more tearout and believe me, it wasn't very much! So now I'm going to soak it again and see what happens. I expect to use a shear cut again and with one cut have the bowl ready to finish. If you are expecting a miracle however, be prepared to spend a lot more money.

 

[DMcIvor]

white glue

I've used the PVA soak method on a few pieces and it certainly saved them from the wood stove. As others have suggested, I use a 50:50 dilution. I let the piece soak 12 - 24 hrs, then dry another 12 - 24 hrs before finish turning. Penetration varies, of course, but seems to be about 1/8", so you do want to be fairly close to your finished dimensions before soaking. I find that the glue/water solution begins to thicken noticeably after 12 hours or so, so I think penetration slows significantly at this point and I doubt much benefit is gained from longer soaking.

Don McIvor
Twisp, WA

 

[Stick Fast]

stablizing and hardening wood

I thought I would throw my two cents in...
You might try Thin CA to stabliize and harden punky areas.

I talked to one turner who saturates the heart of the wood with thin CA. He said it greatly reduced cracking. I have not tried this (should have by now) but this sounds like it would work.

I have seen many turners use CA to stregthen thin wood and to keep bark on fro a natural edge while turning.

John :cool2: