|Project by leonmcd||posted 07-31-2007 09:08 PM||3991 views||9 times favorited||16 comments|
My niece recently asked me to make her a step stool and Lumberjocks has a wood joinery contest. At first a complex step stool with twenty eight joints that was designed for people to stand on did not seem the ideal project to do without glues, metal nails, screws or other mechanical fasteners!
That was until I discovered “wood welding”. I’ve followed the discussion on contest rules and as far as I can tell there is no restriction on “wood welding”. This project is 100% wood (except for a little of my DNA).
The step stool has a pecan frame and the steps are honey locust. The dowels are the cheap some kind of white wood variety. Except for the steps, all the joints are lap joints “welded” in place with dowels. The steps are butt joints “welded” in place with dowels.
So what is “wood welding” you ask?
Since I’ve never created any joinery without glue, I hit the internet looking for glueless joints. I found a reference to “wood welding” which is a commercial process that uses vibration and pressure to join wood without glue or fasteners. It was discovered in 2005 by accident when a technician forgot to include the plastic sheet that they put between the two pieces of wood before welding. Seems that the wood stuck together just fine without the plastic. Just wood on wood. Some of the wood components actually melt and fuse back together to form the weld. It forms a joint in 3-4 seconds that is as strong as a glue joint after 24 hours.
The only down side for me was that the commercial process uses machines costing thousands of dollars.
Luckily I found a tiny reference that hinted that you could do the same thing with dowels and a hand drill.
Unfortunately, it did not say how. After quite a bit of experimenting, I discovered that I could use a hand
drill to put a 3/8 dowel in a 5/16 hole and it was definitely welded. Using pliers I could twist off the
dowel without breaking loose the weld.
I learned that there are some tricks to doing this and I plan to put together a video blog to demonstrate the process.
-- Leon -- Houston, TX - " I create all my own designs and it looks like it "