Wood Hardener? Stabilizing?

[Tom Albrecht]

Has anybody here used Minwax Wood Hardener successfully for blanks of any kind?

 

[david munyak]

I have used it but I wasn't very happy with the results. It didn't seem to penetrate very well or stiffen things up enough.

I've been more pleased with Liquid Wood by Abatron which I used occasionally back in my carpentry days to treat wood rot. It's a two part epoxy but has a very thin consistency.

I've also been using West System epoxy which is more viscous, but following their advice and heating the work before applying the epoxy encourages deeper penetration.

 

[Richard Coers]

It's 72% acetone and 3% methanol. So not much left to harden the fibers.
https://www.minwax.com/document/MSDS/en/027426417007

 

[Tom Albrecht]

Thanks David,
I am toying with the idea of using something with a vacuum chamber, but not the typical Cactus Juice stuff. I have some bigger pieces (not pen blanks) that won't fit in a conventional toaster oven for curing. Plus, the whole heated curing process looks cumbersome.

 

[Tom Albrecht]

It's 72% acetone and 3% methanol. So not much left to harden the fibers.
https://www.minwax.com/document/MSDS/en/027426417007

Hmm, and 25% what?

 

[Tom Gall]

Has anybody here used Minwax Wood Hardener successfully for blanks of any kind?

Although it has been at least 10 years since I last used the stuff I was happy with the results. I did use it occasionally by brushing it on soft spots to stiffen the fibers, turn the area, and re-apply if necessary to get good cut.

But I primarily used it on small diameter discs (2”-3” x ¾” or less thick) of softer woods (quilted & curly maples, burls, spalted wood, etc.) to change the densities and working properties without changing the wood color…..(think jewelry, medallions, pendants, etc.)

I would put the Minwax W-H in a small container (cat food cans) and submerge the wood by holding it down or weighting it. When the air bubbles stopped coming out of the wood I knew the hardener had penetrated completely. Remove and let dry. Because the hardener is expensive, I believe it was about $10 a can more than a dozen years ago, I would return the unused /un-absorbed remainder back into the Minwax container with a small funnel. Worked for me!

 

[olaf Vogel]

Hmm, and 25% what?

Try epoxy resin, thin it down with alcohol to desired levels.
Obviously thinner penetrates better.

Acetone works as well, but stinkier. Its winter, so I'm working inside.

 

[hockenbery]

Thin epoxy mentioned above is worth a try.

I have used a product called pollyall 2000.
The best thing I can say about it is that it works and it turns nicely.

It is a bit pricey, has a short working time, give a plastic appearance to the wood.

It made it possible for me to turn a nice hollowform from wood that was crumbling apart.

 

[Richard Coers]

Hmm, and 25% what?

Before we could buy the current stabilizing resin, folks were melting scrap plexiglas in acetone. It was a bit like using shellac flakes. You cut or broke up the plexi into little pieces, then placed them in a glass jar and added the acetone. Periodic shaking to keep it in solution, and adding more acetone as it quickly evaporates with the lid off. It worked pretty well for stiffening fibers, but not close to the results of the current heat cured resin.

 

[david munyak]

Thanks David,
I am toying with the idea of using something with a vacuum chamber, but not the typical Cactus Juice stuff. I have some bigger pieces (not pen blanks) that won't fit in a conventional toaster oven for curing. Plus, the whole heated curing process looks cumbersome.

Tom,

I haven't used a vacuum chamber or the cactus juice, though I've considered trying both. The benefit might be deeper penetration, but who knows without testing.

The things I've used these products on were primarily bowls of spalted maple. I've heated them in a conventional oven or with a heat gun, but the heating was prior to application of the epoxy, not after. Having the epoxy warm helps too (during warm weather. Not by heating the epoxy), but it accelerates the cure so using a slow formula helps then.

The warm wood does seem to draw in the epoxy so multiple applications are required to fully soak the wood. Maybe this is what you were referring to being cumbersome.

The Liquid Wood doesn't require pre-heating, though I'm sure it would help.

 

[Bill Boehme]

Has anybody here used Minwax Wood Hardener successfully for blanks of any kind?

I agree with everything that Tom Gall said, but I would add that the price has increased significantly. I have used it a lot for small things like pen blanks and cabachons, but it has been a few years since I last used it. It is designed to be used on "dry rotted" architectural elements such as window sills and porch columns. Bad wood soaks it up like a sponge.

Judging by the smell, I would have guessed that it was mostly MEK, but it is possible that the formula was changed. The 25% what is some type of acrylic plastic. I think it is best for small decorative pieces of highly figured punky or spalted wood.The last thing that I used it for was a punky stump of a large old rose bush. It was great for that, but it has some significant drawbacks such as:

• It gets extremely hard and abrasive so it dulls tools quickly.
• It produces strong fumes.
• It's terrible to sand because of the noxious dust. I only sand it outdoors while wearing a powered respirator.

On the positive side, it doesn't darken the wood nor does it give it an amber tint.

 

[olaf Vogel]

The warm wood does seem to draw in the epoxy so multiple applications are required to fully soak the wood. Maybe this is what you were referring to being cumbersome.

From my reading, warmth increases the viscosity of the epoxy, hence it will penetrate better/deeper.
The wood usually has more thermal mass than the epoxy, hence will absorb more heat (from the epoxy), so heating the wood is more effective than heating just the epoxy and not the wood.

Increasing viscosity by adding thinners has similar results, but in addition to heating.
So if you want really deep penetration (like me) then do both.

 

[Tom Albrecht]

Lot's of good info here, thanks.

For those of you who have used and thinned the West System epoxy, how long is the set-up time?

I checked out the PolyAll 2000 site, and that sets up in in 8 to 10 minutes, which seems a bit short for deeper penetration.

 

[olaf Vogel]

I dont use West for finishing. Too expensive. Good for gluing where strength is needed.

Art Resin is my choice (only because I inherited a few gallons from my wife. She bought it to resin her paintings, but it has a yellowish tinge, which I don't mind on wood)

I found that set up time varies widely depending on temp, and dilution.
West has good info in the guide, but (if I remember correctly) also a wide window.

______________________________________________________________________________

Also, the stuff for fixing cars "might" be a possibility. Much cheaper. Its a polyester based resin.
I didn't understand the difference until last year, when I made customer Stand Up Paddle-board. Apparently the polyester resin dissolves foam boards...epoxy does not

But I've not tried the polyester stuff on wood finishes.
I know it sticks!

 

[david munyak]

For those of you who have used and thinned the West System epoxy, how long is the set-up time?

West has several hardeners with different speeds, but for this you want their 207 Special Clear Hardener. They say it has a pot life of 20-26 min at 70 deg. and cures to a solid state in 10-15 hours. I think it could be less but I usually wait overnight. I'm always doing three things at once so the time doesn't matter much.

Not sure how thinning affects the cure time. I've thinned a little but they don't recommend it because they say it compromises strength and water resistance. Not as much of an issue in non structural applications, but I find I like the results better with the heated wood method.

 

[Richard Coers]

From my reading, warmth increases the viscosity of the epoxy, hence it will penetrate better/deeper.
The wood usually has more thermal mass than the epoxy, hence will absorb more heat (from the epoxy), so heating the wood is more effective than heating just the epoxy and not the wood.

Increasing viscosity by adding thinners has similar results, but in addition to heating.
So if you want really deep penetration (like me) then do both.

Heat and thinners reduce viscosity.
Temperature
A fluid's viscosity strongly depends on its temperature. Along with the shear rate, temperature really is the dominating influence. The higher the temperature is, the lower a substance's viscosity is. Consequently, decreasing temperature causes an increase in viscosity. The relationship between temperature and viscosity is inversely proportional for all substances. A change in temperature always affects the viscosity – it depends on the substance just how much it is influenced by a temperature change. For some fluids a decrease of 1°C already causes a 10 % increase in viscosity.

 

[John Tisdale]

Aero Marine 300/21 is a much lower viscosity epoxy.
How much it penetrates depends on wood species. While I doubt it penetrates very deep, it does go into small cracks and can even by injected with a #22 syringe - you can even reuse the needle or share with a friend.

 

[Tom Albrecht]

West has several hardeners with different speeds, but for this you want their 207 Special Clear Hardener. They say it has a pot life of 20-26 min at 70 deg. and cures to a solid state in 10-15 hours. I think it could be less but I usually wait overnight. I'm always doing three things at once so the time doesn't matter much.

Not sure how thinning affects the cure time. I've thinned a little but they don't recommend it because they say it compromises strength and water resistance. Not as much of an issue in non structural applications, but I find I like the results better with the heated wood method.

Doesn't the "heated wood method" shorten the curing time, and consequently shorten the time the epoxy has to settle in to the voids?

 

[Tom Albrecht]

BTW, what I am gearing up to here is filling voids in some spalted cherry 2" X 2" blanks that I want to use for tool handles.

 

[hockenbery]

I checked out the PolyAll 2000 site, and that sets up in in 8 to 10 minutes, which seems a bit short for deeper penetration.

Pollyall is really thin so it penetrates punky wood well brushing on. The depth varies with the wood punkyness 1/8” to 1/2”.
I don’t remember the working time being more than 5 minutes at best
I would mix a small amount brush on 3-4 brush strokes an it would be setting up in the mixing dish.

I rough turn. Apply pollyall. Finish turn and apply more Pollyall in spots as I finish turn.
Then I hollow the form. You can turn it almost as soon as you wipe it on.

To get more penetration you may need to use vacuum.

 

[Mike Brazeau]

I have not used Minwax Hardener because of the noxious composition. I majored in Chemistry and had enough of organic solvents in my undergrad years. Some of our guild members use it successfully. I came across an aqueous polyurethane product a few years ago at our local Home Hardware and I believe it is sold in the US by Home Depot. Called PC-Petrifier. I used it much as Al has detailed for some soft spots on spalted maple for a wig stand and it worked well. Have been going to try immersion soaking with possible vacuum of some pen blanks but never get to it. It did not color the wood and it turned really well. No real troublesome odor. I only have 16 oz bottle but it is available in larger quantities. Check it out at www.pcepoxy.com they have some interesting products.

 

[Bill Boehme]

BTW, what I am gearing up to here is filling voids in some spalted cherry 2" X 2" blanks that I want to use for tool handles.

Have you considered using clear Inlace?

 

[david munyak]

Doesn't the "heated wood method" shorten the curing time, and consequently shorten the time the epoxy has to settle in to the voids?

Yes, it does. But with the fairly long cure time spec'd, even cutting it in half gives a pretty long window for penetration.

 

[Michael Nathal]

I am not so sure that thinning epoxy with alcohol or acetone increases penetration. I don't doubt that it decreases viscosity [note some of the posts above mentioned increased viscosity as desirable. I assume they meant the opposite: lower viscosity means less viscous, more like water and less like syrup.] I have heard that when you use thinned epoxy, only the solvent penetrates deep, leaving the larger epoxy molecules at the surface as if it was unthinned. Same reasoning goes for thinned finishes like oil-based poly, that thinned finishes do not penetrate any deeper than regular finishes. I really don't know which alternative is correct as they both seem to make sense.

 

[olaf Vogel]

Micheal,

I had inverted the definition of viscosity above. Sorry for the confusion.
However the rest of it stands. Thin epoxy with acetone or alcohol and the “mixture” penetrates the wood. It’s not as if the alcohol separates out, when applied, then sinks in, while the epoxy stays on the surface.

Of course penetration will vary depending on the wood type, condition etc.

 

[Tom Albrecht]

Have you considered using clear Inlace?

No, I haven't. Isn't that pretty much just another form of epoxy for holding the color granules?

 

[Bill Boehme]

No, I haven't. Isn't that pretty much just another form of epoxy for holding the color granules?

No, it isn't an epoxy. InLace acrylester is Reichhold Polylite 32153 that has been repackaged in small quantities for hobby and art use.

Unlike some isophthalic polyester high styrene laminating resins such as those used in fiberglass work, Reichhold Polylite 32153 is an orthophthalic casting resin that is water clear and has zero shrink when curing. Reichhold makes a wide range of resins for applications like molds, laminates, counter tops, fiberglass, bowling balls, etc. Some of the resins are rigid and some have various amounts of flex.

While Inlace may not bond as strongly as epoxy, in my experience it appears to make a good bond with wood. Of course Inlace, CA, and epoxy all cure hard. Some wood moves a lot more than others so it makes sense to only use well behaved wood for inlay work.

 

[Steve Worcester]

I you have a material and want to increase surface hardness, then an epoxy or minwax type product will work. If you want 100% penetration and hardness to the entire piece, stabilizing in a product like Cactus juice is the way to go. But there is some preparation and you will need vacuum to get the full penetration and an oven to cure it (and actually an oven to dry the wood too).
But what stabilizing will not do is fill voids and cracks (or at least not well), it is not a glue. While it would appear to work, the structure of the cured "juice" is not strong on its own.

 

[Michael Nathal]

Micheal,

I had inverted the definition of viscosity above. Sorry for the confusion.
However the rest of it stands. Thin epoxy with acetone or alcohol and the “mixture” penetrates the wood. It’s not as if the alcohol separates out, when applied, then sinks in, while the epoxy stays on the surface.

Of course penetration will vary depending on the wood type, condition etc.

I am curious on how you know that. I am not saying you are wrong. I just want to understand the evidence. How do you know that thinned epoxy penetrates deeper?

 

[olaf Vogel]

Michael, if you are asking for scientific analysis then no, I've not done that.

My exceedingly accurate method of observation was: watch the change in color. A richer color is usually in indication that the finish has soaked in deep. I tried that on several similar bowls, with thinned and regular.

For most cases thats sufficient.

For really punky wood (stuff I can stick my finger through), I literally poure the thinned mixture in, until it stopped absorbing.
(I prefer to retain original characteristics, rather than create a solid epoxy section, with a bit of wood in it.)
Originally I tried the same with regular epoxy and it did not soak in - that started my online research.

If thats not scientific enough for you, let me suggest a solution:
Ideally, you would take several pieces of wood, cut them into pieces (to ensure equal densities) and then treat both with regular and thinned epoxy.
Then trim off the ends to see how far it soaked.

I suspect that results will vary wildly.

As a finish epoxy is pretty awesome stuff. If you are turning larger green wood pieces, where the wood strata is at all questionable, epoxy might be the only feasible solution.
The Minwax stuff is expensive and harder to find, nowhere as durable. Cactus Juice I've not tried, because my work wont fit into a suitable vacuum chamber. CA is great but way too expensive as a finish for bowls.
And epoxy is tough as hell...you are basically plasticizing your work. Its easy to tint. It can fill large gaps / holes. You can embed items.

This is why epoxy is frequently used for live edge table tops and similar products.

However, it has a certain look: high gloss, very thick finish. And can be spectacular, in the right application.
I did one vase of extremely spalted maple (basically rotted) that was so soft you could pull chunks off with your finger nail.
Epoxy worked, it looks great and the piece sold for a really high amount.

But, overall epoxy is not actually my favourite finish since the work looses the texture of the grain. For that, I use shellack.

 

[Pete Blair]

I like and use the Minwax wood hardener. Seems to work well for me. My process is to turn close to final thickness, then harden and finish. Has saved me lots of beautiful spalted Maple.

 

[James Penuel]

Has anyone tried PC-Petrifier Wood Hardener? I saw an ad for it on Pinterest. It is available online at Home Depot for $40/gallon. Product info says it is water based, so sounds like it might be less toxic than Minwax WH.
Saw a video of turning thin goblets from green cherry and the turner used what he termed a clear hardening paint, called “Kigatame Ace” in Japan

View: https://www.youtube.com/watch?v=4zwk5wH4xA4

Any ideas on comparable products available in US?
Thanks,

 

[Scott Lynn]

Not sure if this would work and its just a thought couldnt you put danish oil in a vac with wood like stabilizing and let it dry, would it stabilize the wood since both active ingredients are lintseed oil and poly and both harden plus the mineral spirits makes it thin so it would penetrate deeper.

 

[Doug Freeman]

Dont want to put any product with volatile solvents under vacuum. They will all evaporate before much vacuum is achieved and the vapors will ruin a vacuum pump.

Low viscosity epoxies/urethanes under pressure may be the best solution.

 

[Bill Boehme]

Not sure if this would work and its just a thought couldnt you put danish oil in a vac with wood like stabilizing and let it dry, would it stabilize the wood since both active ingredients are lintseed oil and poly and both harden plus the mineral spirits makes it thin so it would penetrate deeper.

In addition to what Doug said, the danish oil wouldn't penetrate very far into the wood if it is still wet. Also, the danish oil would significantly seal the wood and prevent the moisture from escaping.

 

[Gerald Lawrence]

In addition to what Doug said, the danish oil wouldn't penetrate very far into the wood if it is still wet. Also, the danish oil would significantly seal the wood and prevent the moisture from escaping.

Correction oh great one, It may be called sealing but finish does not seal the moisture in . Finish slows the exchange of moisture but will not prevent it. This is why wood moves seasonally , moisture exchange.

 

[Bill Boehme]

Correction oh great one, It may be called sealing but finish does not seal the moisture in . Finish slows the exchange of moisture but will not prevent it. This is why wood moves seasonally , moisture exchange.

That's why I said significantly seal. I am well aware that even a thick finish isn't completely impervious to moisture. Also, bad things such as the wood turning black if loss of moisture is slowed down too much. I have had that happen even with Anchorseal on very wet rough turned maple bowls. I'll maintain my belief that the procedure proposed by Scott wouldn't work out as hoped.

 

[Roger Wiegand]

I am curious on how you know that. I am not saying you are wrong. I just want to understand the evidence. How do you know that thinned epoxy penetrates deeper?

The epoxy monomers are, to an order of magnitude or so, the same size as the acetone and are fully miscible with the acetone. Even the pre-polymers are tiny (30-70,000 MW) on a scale of cracks or the natural tubes of the xylem and phloem of wood. There's no way you could achieve separation. Such polymers should even penetrate cell walls in the wood, the porosity of the cell walls will allow permeation by molecules in that same 50K molecular weight range.

 

[Scott Lynn]

In addition to what Doug said, the danish oil wouldn't penetrate very far into the wood if it is still wet. Also, the danish oil would significantly seal the wood and prevent the moisture from escaping.

Makes since thank you was curios about it.

 

[Randy Anderson]

I'll add on to this thread rather than start a new one. I was terrible at chemistry in school and many of you have some solutions here that are likely good ones but deeper in than I want to go. Once again I almost passed on some punky wood from an old hickory tree. Very punky, turned one natural edge bowl, sharp gouge, light cuts with shear scrape and with NR scraper, etc then sanded with 80 till I got most of the tear out pits out then finished sanding out to 240. With oil finish it looked great. I took it with me to my latest market show and it sold in the first few minutes for more than I ever expected I could get for it. Net, I'm turning more (second one in pic attached). I have some JB weld wood hardener that I plan to apply after I get to almost final shape. Let soak in, harden then turn off more just enough to see if I can get below the tear out pits.

Anyone done it this way? If so do I soak sooner and turn off more? It's dry and will soak up a lot I think. I assume I'll need to sharpen a lot but not sure how hard this stuff gets. Concern also as to how it will impact my oil finish. Blotchy? Won't take?