Moore Woodturning November 2011
By Fred Holder
Drying wood without cracks or checks and with minimum distortion is a problem near and dear to nearly all woodturners. Why just woodturners? Mostly, because we are more likely to use woods taken directly from the tree than other woodworkers. Many turners rough turn their bowls, etc. when the tree is first cut and allow them to dry on the shelf or in a pile in the corner. Others, like me, seal the ends of the wood and put it on the shelf to dry for one or more years. This process seldom keeps the wood from checking some as the stresses in the wood express themselves, our goal, therefore, is to minimize the checking. There are more ideas for doing this than I can name and new ones come up all of the time.
I used the PENTACRYL until I ran out and then, as usual, started trying other things. I don’t believe any of them performed as well as PENTACRYL.
In 1998, the people from PENTACRYL ran an advertisement in More Woodturning and sent me a sample to try. As I understand it, this product works best if the wood is very wet. If you are turning green, rough turned bowls, try to keep them wet before you apply Pentacryl (this will also keep them from cracking before being treated). The water in the wood seems to help in the penetration of the Pentacryl. I tried it and had some questions. They sent me the following information and gave permission for me to reprint it. I present it here for your use and consideration:
“Pentacryl, a non-toxic compound of modified polymers, was originally developed for the treatment of waterlogged wood. It has since been marketed for woodcarving and woodturning to keep green wood from cracking and splitting during the drying process. PENTACRYL will not discolor the wood, is non-hydroscopic, will not oxidize, decompose or migrate in the wood when exposed to different degrees of temperature and relative humidity.
Many types of wood have been treated with excellent results including: eastern white pine, aspen, madrone, basswood, tupelo, walnut, applewood, hawthorne, cherry, rock maple, soft maple, ash, and others. PENTACRYL can be brushed on or the wood can be immersed into a 100% solution of PENTACRYL.
Although soaking is the preferred method, excellent results are still obtained by the brushing method”. Note that if you are working with wood that is semi-dry or has a lower moisture content, you can use
WOOD JUICE. This works the same as PENTACRYL, but is formulated to penetrate wood that is drier. One test that I did in 1998 follows: I cut some top blanks (2” square by .” thick) from some very wet wood. I’m not sure at this point whether it was pear wood or holly. They were scraps off of some wood that I was helping my friend Roger to get ready for turning. Anyway, I had just received a bottle of PENTACRYL for evaluation, so I doused these blanks with PENTACRYL using a brush and set them on the shelf to dry or crack or something. Well, I’m happy to report that they didn’t crack and when I checked after a few days they were completely dry. So, I drilled them and inserted 3/8” dowel sections 2-1/2” long along with a little Tightbond II glue. The wood was completely dry to the touch and it turned great. I repeated this test on a number of different pieces of wood and found that they didn’t crack and they seemed to dry quickly.
That was in 1998, I used the PENTACRYL until I ran out and then, as usual, started trying other things. I don’t believe any of them performed as well as PENTACRYL. Recently, the company sent me a gallon of their PENTARYL to test again. I’ve not had a lot of wet wood since it came in, but I did try it on a piece of what I think was wet elm. It was cracked on both ends. I cut away the cracked parts and cut it into two 3” long pieces to become Chinese Ball blanks. I painted on the PENTACRYL until it would accept no more and set them on the shelf to dry. About a month later, I took one and turned it into a Chinese Ball. There were no cracks in the wood and it turned well. As near as I can tell, the product is as good as it was in 1998, maybe even better.
You can contact them at:
Preservation Solutions, LLC.
Golden, CO 80403
Phone: (303) 642-3060
Fax: (303) 648-6486
Web site: https://www.preservation-solutions.com