Home built computer controlled dobby

Over the weekend I met the incredible Maurice Blackburn. He is a weaver that has built 2 looms from scratch. He then built a computer controlled system for one of them using an Arduino. He wrote and article on it that appeared in the Oct 2012 Complex Weavers Journal.

I ran into a snag on my loom build. I have it set up for 16 shafts, but it is only 22" wide and that doesn't leave me enough room for more than about 12 treadles. Adding an electronic dobby will solve this dilema for me! I plan on building one for my loom the winter.

Comments

Posted on Mon, 08/26/2013 - 21:32

You could build or buy a mechanical dobby system, one with bars and pegs, or you could build or buy a computer-assisted module. However, the term "compu-dobby" has been trademarked by AVL Looms so the only actual compu-dobby is one of the models manufactured by AVL. I think there are 4 different models now. Besides using bars and pegs, there is another mechanical dobby that uses heavy paper or plastic with holes. Cyrefco used to make these in California to fit Scandinavian style looms. I have seen looms with plastic sheets in Vaxbo, Sweden, weaving table linens. Any of these styles of dobby loom can have one or two treadles.

Bonnie Inouye

Posted on Tue, 08/27/2013 - 14:11

I'm sorry for stepping on a sensitive naming issue. I end to refer to cola flavored drinks as "Coke" and facial tissues as "Kleenex" as well. I ment no offense or trademark infringement and have edited the post.

Posted on Thu, 08/29/2013 - 20:00

You could build either kind of dobby. (I just happen to know that compu-dobby is registered by AVL and they can be sensitive on this issue; I don't work for them but I own 3 of their looms and have taught at their factory-classroom in Chico, CA.)

A 16-shaft loom of this width could work with levers, as a table loom, but of course it slows your progress on the cloth. Even if you had space for 18 treadles, that can be a severe restriction when there are more than 2000 combinations available. Making or buying a dobby head of either kind would be great!

Bonnie

Posted on Thu, 10/17/2013 - 19:53

I got nearly finished on a dobby controller last summer, but final year and work stopped the project in it's tracks.

 

I used servo motors with a dedicated servo control board. They don't get heated up like solenoids, they're also easier to bvuy as a normal consumer on ebay or whatever. On top of that, servo projects are very common in the hobbyist RC car/Robot builder community so there's a wealth of information on how to use them.

 

I have also been considering a countermarche style system whereby the shafts are at rest in the centre of the shed and a circular chain with both a lifting and lowering bar attached raise and lower the shafts.

Each shaft would be having a flat steel bar protuding from it's lower portion, with a doublefaced hook on it, which can be pushed or pulled to one side or the other. In this way the raising shafts can be balanced against the lowering shafts and you eliminate problems associated with having to lift all shafts against the pull of gravity, and can do away with systems of leverage or large scale mechanism. 

I have woven on looms using a system similar to the one I described and i feel they are vastly superior in both mechanical simplicity and ease of use to the top or side loading dobby which lifts all shafts from a lowered position