A Dryer For Turned Wood
This is a description of the "dryer box" that I use.
To recycle an old dishwasher, remove the motor/pump, center nozzle and silverware basket. Keep the racks. Place a drop light with a 100-watt light bulb in the bottom of the box, running the cord through the hole where the pump was. If the motor/pump is left in place, remove the plug and pass the cord through a ½" hole drilled in the side of the box, and then attach a new plug. Also, drill a 1/8" hole through the door for a kitchen thermometer, the kind with a dial and a probe. The new dryer is complete.
I have used these dryers for nearly ten years. I can keep the temperature inside the box at about 95ºF with a 100-watt light bulb, and lower the wattage to 75 or 60 if it exceeds 100ºF in the summer. A bowl that is finish-turned to ¼" to 3/8" thickness will stabilize to around 10% moisture content in about 3 days, depending on the species, and the original moisture content. Thicker wood or a full 'dryer' will require a longer time.
Cracking and distortion is no more of a problem than with air-drying. For a slower drying rate, I either fill the bowl with wet shavings, wrap the piece in a grocery bag, place a pan of water in the bottom of the box, or do all three. The objective is to raise the humidity inside the box and slow the evaporation rate from the wood surface.
The slightly elevated temperature and low humidity in the box also makes it an excellent drying chamber for varnish and oil finishes.
© 2002 - 2009 by Russ Fairfield. All rights reserved. No parts of this publication may be reproduced in any form or by any means without the written permission of the author.