Wood hardener v CA

In message , Darrell Feltmate writes

Hi Darrell,

Thanks for the hints, it sounds like anything that will A. soak in B. Harden

Might be suitable options. It sounds like time for me to see what I can find and experiment.

Maybe I should get a large chunk of Balsa and use that as the basis of testing each, it should give a reasonably constant soft base line. Any thoughts?

If any of the local kids ever pry themselves away from video screens and make rockets, balsa turning is a useful skill. A light touch, and a good deal of abrasive shaping/finishing - no hardener required. A few coats of old-fashioned airplane dope for an excellent finish.

As far as I can tell, the "wood hardener" product that's a milky liquid is exactly the same as, but more expensive than, waterbased acrylic wood finish.

That's what our Science Olympiad team did, turned balsa for nose cones. I had 'em start with bass and then eastern white cedar, which is brittle like balsa. The best two had it down after a couple of each. What ended up the best was a greased piece of bass with plastic heated over it to conform. No, I didn't push any particular way as best. I know the rules!

Acrylics are water-soluble "bulkers" that keep fragile and brittle grain in line, and limit the distortion of the piece.

In message , Ecnerwal writes

I hadn't actually intended to turn the balsa, just use it as a base line for the effects of hardening, though it sounds like it may be an interesting experiment in its self

The wood hardener I was thinking about is actually clear (Ronseal Wet Rot hardener). After speaking to the manufacturer they reminded me that you need to inject it by using holes, and that its penetration is only about 5mm. Also if you need to treat woodworm then that needs to be done first.

And the big kicker is that the compounds used in the hardener mean that only their wood fillers will adhere to it, some form of chemical bonding. Which essentially means that normal waxes varnishes etc. will not normally adhere.

At least they didn't say it was impossible, but gave encouragement to give it a try.

JD

How long does it last? You keep it in the fridge?

I pick it up in I think 20 ounce bottles - I've never had it go bad in the bottle. I usually keep it in the fridge (now, there's a dated word for you) just so I can find it when I need it, and pour it into 2 ounce bottles to put by the lathe - I have had it harden up in the 2 ounce bottles, but usually after a year or two - I have to buy more every 2 or 3 years, depending on how much I'm using the lathe. I get it from a guy at a local swap meet, but if you get some friends together it is cheapest if you buy it in 5 gallon drums - just search the web here are some random links to get you started

> FWIW, CA glue is not that expensive if you buy it by the quart - it's >> only >> expensive in those little tiny bottles - I pay around $2 per ounce > > How long does it last? You keep it in the fridge? >

Hello John,

I've used numerous wood hardeners, both manufactured and home brews. Minwax wood hardener is a good product that is available any any home centre. It is not water based, or milky. It is a solvent based product that contains Acetone 72% and Methanol 3%. It works very well and cures into a very hard, clear material.

Small areas can be easily hardened with cyanoacrylates, but you will need to pretreat the area and adjacent wood fibres with a spray shellac, or lacquer to prevent CA's nasty wicking habit from rearing its ugly head.

On some soft areas, a simple spray of lacquer or shellac might do the trick... It really depends on how compromised the cellulose structure is... You can also use various soaking hardeners, thinned epoxies (I use these all the time) and witches brews to harden and stiffen the wood fibres. However, each of these has pros and cons, so you have to evaluate each project separately. Best of luck to you and take care!

John wrote: : The wood hardener I was thinking about is actually clear (Ronseal Wet : Rot hardener). After speaking to the manufacturer they reminded me that : you need to inject it by using holes, and that its penetration is only : about 5mm. Also if you need to treat woodworm then that needs to be done : first.

There's a thin epoxy designed for use on boats, at

I don't know about finishes, but it penetrates a lot deeper than 5mm. -- Andy Barss