Thursday, November 06, 2008

Sticking to Woodturning

There is some debate over the most important additions to the woodturner's arsenal in the past century or two. I am not going to pretend to have a definitive answer, just a couple of observations. Tool innovation has really only made small changes to hollowing, cutting and scraping tools. The four jaw chuck has made life easier in holding work but can be worked around by other methods.

I think one of the great advances has been the improvement in glues. Cyanoacrylate or CA glue in particular is used by woodturners on a daily basis. Thin CA can be dripped into a crack followed by fine dust from the same wood and the crack is almost invisible after the finish is applied. Some people use thin CA as a finish on small objects. Thicker CA is used to glue in brass tubing for pens and other projects. It is also unique in that it can make an almost instant bond with wet wood and can be used to hold a green piece to a waste block for turning.

Still, one of my favorite uses for CA is to simply hold wood together for turning. This CA dripped into a punky spot will keep it hard enough to turn. Thicker CA can glue together a piece that would otherwise split off.

CA has helped us to become better users of rare resources, pretty woods.


Jacki- Falkenbury Farm said...

My son recently turned a couple BEAUTIFUL bowls. This morning they are both cracked to what looks like, beyond repair. We put mineral oil on them frequently. One bowl was cherry and he turned it green..... the other black walnut. Any advice you could possibly offer would be great. Would CA have helped and saved the bowls? Or was it bound to happen as the wood dried? Also, was mineral oil what we should've been using? So much beautiful work g-o-n-e. He loves turning. He is 18 and wants to do more but obvioulsy does not want to waste his time if they'll keep cracking. Help please!!

JJ Worthington said...

I just read a great article by a guy (wish I had kept his name and the article) who only turns wet/green woods. His advice was to allow wood to dry, after turning, in paper grocery bags. Roll and close the opening. The paper apparenly serves as an ideal breathable membrane that allows moisture to escape at the appropriate rate to drastically reduce cracking, but he also pointed out that depending on the cut and freshness that sometimes a piece will crack regardless of precautions. He also pointed out that bowls often flex and warp in drying and that should be embraced as it is charachteristic of the material causing beautiful natual transformations. As a ceramics artist I never put too much time, effort, or emotion into a piece that I can't remove it from the wheel and throw it against the wall and start again. Of course there are moments of frustration and disappointment, but when each piece is approached with that mindset those moments are fleeting. Back to topic, the author also pointed out that in a desert environment you might use 3 bags to retain the moisture inside the bag instead of one bag to allow adequate time in drying to avoid those pesky cracks. I cannot verify the results as I have just started using bags myself, but I believe the reasoning is sound.