Pentacryl, Polycryl and Woodjuice

[nicguthrie]

Hi folks, quick question - I've been looking at these products on turners retreat - at first out of simple curiosity as I wondered what they are, then with growing interest...

I have a number of different very beautiful spalted blanks for the pens and things I'm making, and I've been having success with the thin CA glue that was suggested here to stabilise them, and also with cellulose sanding sealer added as the wood gets thinned. I've often wondered how I could handle any really soft ones tho, or bigger blanks. The wood shop down the way from me has a few chunks of utterly gorgeous spalted birch or sycamore that I really fancy getting my hands on, but I'll have to work thru my current stash a little in order to justify it, so I've got some time to think about it in preparation.

The 3 products in my title, Pentacryl, Polycryl and Woodjuice all seem to be for stabilising soft or crumbly woods and I simply wondered if anyone had any experience with them, and whether they were worth the cash (they ain't cheap!) or just yet another gimmick product out to separate us from the content of our wallets.

As always, any (constructive) input appreciated!

Nic.

Link, in case they're news to you too...
http://www.turners-retreat.co.uk/accessories-1/workshop-accessories/pentacryl-32-fl-oz
http://www.turners-retreat.co.uk/accessories-1/workshop-accessories/polycryl-32-fl-oz
http://www.turners-retreat.co.uk/accessories-1/workshop-accessories/wood-juice-32-fl-oz

 

[Paul Hannaby]

Pentacryl and wood juice are for stabilising unseasoned timber rather than for hardening it so I don't think they will do what you want.
Out of the three, the Polycryl sounds like the one you want.

There are other alternatives - go to your local DIY store and look for wood hardener (used for fixing rotting window frames etc.) or the Toolpost also sell a wood harener but I don't think it's any cheaper than the Polycryl.

As you've already found out, glue and sanding sealer can also be used.

 

[nicguthrie]

Thanks. I'll look into the wood hardener stuff, it's just for the occasional larger bit of these sorts of timbers, as I can't see me being patient or accurate enough to superglue soak a 6 or 8 inch bowl.

So, if I understand correctly, you can use the other stuff in place of waiting for green wood to dry out completely and it'll stop it warping after turning?

Thanks for the tips.

Nic.

 

[petercharlesfagg]

Hello, some time ago I tested these products for "Woodturning" magazine and I thought you might appreciate reading my test report?

Regards, Peter Charles Fagg


My report went thus:-

Some years ago I tried using PEG (PolyEthyleneGlycol) as an attempt to stop some timber from cracking and therefore becoming unusable. It was a successful trial but considerable time was spent waiting for the timber to cure and I was never very happy with the surface finish when the wax was applied.

Therefore I looked forward to trying these products from the USA. Pentacryl, Polycryl and Wood Juice . They are produced by Preservation Solutions in Colorado, USA.

Pentacryl is designed to be used as a wood stabiliser, in other words to prevent the cracking and splitting of Green wood during the drying process. (2 pints= 1.136 Litres retails @ £16.96. Turners Retreat)
Polycryl is designed to strengthen semi-punky or spalted timber, best used on Green wood and is water soluble. It is usually used before Pentacryl. (2 pints= 1.136 Litres retails @ £14.50. Turners Retreat)
Wood Juice is designed to stabilise dry, semi-dry or sawn Green timber to prevent future cracking or splitting. (2 pints= 1.136 Litres retails @ £13.66. Turners Retreat)

The products are fairly expensive in the UK but it depends on what you are hoping to achieve in the treatment and use of Green timber, they can be used either with a brush* or immersion of the logs/turned items. They can be purchased from Turners Retreat and other outlets.

My trial of these chemicals was conducted over the first 3 months of 2011.

Pentacryl
I started with some freshly cut black mulberry (Morus nigra) cut into logs and then band sawn to size. All cut surfaces were treated to a good soaking and left in a nice dry, frost free place out of the sun for a month. Subsequent inspection revealed some cracking from the pith which was to be expected. I chose a good cross section of the tree and proceeded to turn a small bowl/dish with the intention of making it incorrectly! The turned item had walls of uneven thickness and received a liberal coating of Wood Juice and was then placed inside a plastic bag, as per the instructions on the bottle, this item will be left for a further month.

Subsequent removal of this piece from the plastic bag revealed another down side; it stank and was covered in mould!

Polycryl For this I chose some dry punky (Levels of punkiness not explained) oak (Quercus robur) that I had considered unusable due to the breakdown of the timber under the bark. Polycryl is recommended to be diluted 4 to 1 with hot water in the first application, thereafter to be used neat! (A turner wishing to use this must weigh up the costs carefully. Space must also be considered for treatment and for drying.) After soaking for a couple of days the piece was removed and set to dry in moderate warmth!
Three weeks later the result was disappointing in that it would not dry, it did marginally externally but internally it was as wet as the day it was removed from the neat solution. (By my reckoning it might take 6 months or more before noticeable drying took place!) (Be warned!)

I turned the oak to a cylinder in the hope of using it for some Napkin Rings but the punky wood extends further in depth than expected and the piece may be just firewood.

Wood Juice Pt.2

To test how effective Wood Juice is in preventing cracking in Green timber I coated a few pieces of Oak and Blackthorn on one end with Wood Juice and on the opposite end with another Well Known Product (WKP). Results after 3 months were interesting in that the majority of log ends treated with (WKP) showed significant cracking whereas the Wood Juice ends were almost unblemished! (Possible Picture)

I applied Carnauba wax using the Beall system that I use for all my items and there was no discernible difference as I get with any other method.


Safety First From the web site of Preservation Solutions.
PRECAUTIONS TO BE TAKEN IN HANDLING and STORING: Keep away from strong oxidizers. Handle in well ventilated work areas. When handling; do not eat, drink, or smoke. Avoid contact with skin.
OTHER PRECAUTIONS: Emergency showers and eye wash stations should be readily available. Use proper hygiene after handling this product.

(*Products are not endorsed as food safe in the USA by Preservation Solutions and the FSA (Food Standards Agency) in the UK state that the same conditions would apply.)

 

[nicguthrie]

Wow. Just wow...

Couldn't have asked for a more intensive review on the stuff, thanks very much!

I'll take your experience as a time and money saver then, thanks for that. Worth remembering the woodjuice if I really want to use greeen wood at some point without it cracking, but it sounds worth forgetting all about the other products!

I've never heard of anyone setting things aside in a plastic bag, wet, for a month unless they were actually trying to culture nacteria or mould... I wonder if it was a typo in the instructions and they meant paper? Nevertheless, I think I'll avoid it on the grounds of your report.

Thanks for all this, much appreciated - talk about above and beyond

 

[bobham]

Another "feature" of Pentacryl is that it comes in a plastic bottle that will spontaneously start to leak if left on a shelf for a couple of years.....

Bob

 

[CHJ]

One thing to consider when appraising products developed overseas is the the type of materials they will be used for, in this case wood species, and the expected climate they will be used in.

Something that works well in Texas in a normally hot dry climate may not work so well in the high humidity of Europe.
You see comments on USA forums about differing results with products over the length of the continent.