Wednesday, February 8, 2017

Getting to know you

How the loom works and key takeaways

Hand towels woven on the AVL
You may recall the "new" loom that came into my life late last fall. Although new to me, it is not new. As the 129th loom made by AVL, it is a 12-harness dobby loom that dates to the early 1980's. 

I must admit that I was a little awed by the loom and tried to find out everything I could about dobby looms. I did online research and bought some books. In some respects, the descriptions made it sound more difficult to set up than it is. (Please note: I am not talking about the construction of the loom.)

Dobby bars showing pegs and holes
My personal conclusion is that setting up to weave is simply a matter of rethinking the process. I got a little bogged down with how to peg the dobby bars. But it is very straightforward. Pegging the bars is like manually operating the levers on a table loom. They're either pegged--or not--and the harnesses either lift--or not.

For me, pegging the bar with the small metal pins was a bit counter-intuitive. A peg keeps the harness from lifting and no peg, i.e., a hole, lifts the harness. So, if I want harnesses 2, 4, 6, 8, 10, and 12 to raise, I peg the holes in 1, 3, 5, 7, 9, and 11.

Dobby bars on dobby head
Pegging the dobby bars also made me think about how they entered the wheel. If I pegged the bars from top to bottom and inserted them onto the dobby head, my lift plan was reversed because the bars enter the mechanism from the back. Pegging from bottom to top is the right way to peg them.

My dobby bars are worn and some of the holes are stripped. For the most part, I can feel it through the peg wrench when I screw the pegs in, but not always. I haven't found them all yet so I need to carefully watch the shed and the pattern when weaving as pegs fall out. 

Painter's masking tape and 4 inch cable ties are my new best friends. I use the masking tape to wrap the pegs for the stripped holes, to mark the beginning of the lift plan sequence on the dobby bars and to mark harnesses. The cable ties I use to connect the dobby bars, which were originally connected with metal rings.

Key take-aways for my loom at this point in time:

  • Pegging and assembling the dobby bars 
    • "No peg," that is, a hole in the bar, lifts a harness.
      • Peg the bar for harnesses that should remain in place, that is, don't lift.
    • Watch for stripped holes and use tape (or the equivalent) to wrap the pegs.
    • Peg from the bottom of the dobby bar set to the top. (The AVL manual recommends a set of 20 bars minimum.)
    • Mark the first bar of the pattern weave with a small piece of tape. It's easy to get them out of order. 
    • If the pattern is not balanced, e.g., 6 and 6, peg the harnesses with the greater number of  lifts. This may put the pattern on the reverse, but it is much easier to weave.
    • Connect the chain of dobby bars with cable ties so that the connection is on the back of the bars. When joined from the front, the connector can interfere with the pattern.
  • Weaving
    • Until I am confident that my pegging is correct and the pegs are secure, I need to pay close attention to the lifted harnesses. 
      • I use a small piece of tape to mark the even-numbered harnesses so I can very quickly see whether the correct ones are lifted--or not.
      Rachet that advances dobby bars
    • My dobby mechanism does not reverse. I can disengage the dobby head, but most times it's easier to advance to the next sequence. (Tape on the bars also useful here.)

At this point, my big-picture conclusion is that although the mechanism and construction of my dobby loom is definitely more complex and very different from jack, counter-marche and counterbalance looms, it's not difficult. It's only a different way of looking at the set-up.

1 comment:

  1. Very informative thanks I have just aquired a George Wood 16 shaft dobby loom and I have not found anything to help me with it yet.I am new to weaving I think that I may have started off the wrong way round!at the top instead of from the bottom.