Tuesday, 18 November 2008

Success: 14 treadles on my countermarch loom

My loom now has 14 treadles, all set up and working beautifully, the warp is on and I'll be weaving later tonight.

Here is part one of the story.

The difficulty with adding treadles is that, as Sue commented on my last post, it unbalances the loom unless you add shafts at the same time. The countermarch system doesn't have "balance" in the name, but it is all about good balance. The weight of the treadles is balanced by the weight of the shafts.

This is how the lams on my loom were behaving with 14 treadles in use and 8 shafts (I'm only going to weave on 4, but have some ties on the back shafts to lower lams to help with the balance):

Toika looms should have parallel lams, with equal spaces between treadle - lower lam - upper lam - shaft. The above arrangement was not going to work. So, next stage, down to the kitchen drawer and out with my trusty spring balance (originally bought for use in setting up cam tension on a Ducati motorbike I used to own!).

Going back to school physics lessons, I remember learning about balancing things and diagrams of seesaws with different length arms and different sized weights. I'm not sure I can explain in full, but the further you are from a pivot point the more leverage there is and the less weight is needed to get the arm to balance.

I started by moving the treadle weight closer to the pivot points. There are lots of extra holes in my lams and treadles. I moved treadle 1 to as close as possible to the lam pivot, and I also moved the shafts back relative to the treadles so they were closer to the treadle pivot.

Then to find out how much weight was needed to balance for the four new treadles we had added, we used a peice of string around the top lams and pulled down with the spring balance until the lam was in the level position. In the centre of the top lams, the balance read 7.5 pounds (it doesn't have a metric scale). At the outer end of the top lam it was 5 pounds.

We divided the weight by the number of shafts (8) and made up lead weights from folding lead flashing left from a roofing job. With a couple of holes drilled in the top of each weight they were easily hung under the end of the top lams. Note, for safe handling I shall be making tough cloth covers for the weights.

This shows the new position, see the weights at left hand end of the upper lams:
I've got a warp on now and have been using treadles 13 & 14 for plain weave. The action is beautiful and the shed a good 3 inches.

Now for a different kind of change to the loom. When I bought it, the previous owner had stuck adhesive numbers on the treadles, 1-10. Most of these have peeled off over time, I took off the last few and replaced them with a different labeling that I find easier.
I wrapped green thread around every 3rd treadle, red around every 4th, blue on 5 & 10. I'm better at reading colour and pattern than I am at numbers, I think this will work for me.

Some notes on tying up the treadles, I followed the system used by a friend who has a Toika loom modified to take 16 shafts - she's familiar with lots of shafts and treadles! Her tip was always start with the treadle nearest the lam pivot (the one I think of as number one) and work along. With the treadles not tied up supported (I've got a cardboard box to rest them on) you can see as you go along if one particular tie is putting the lams out of balance. Of course there are times when it is temporarily unbalanced, and you have to make a note of what changed the balance and decide how to counterbalance.

Here's another new tool. With less space under the loom, this time I tied the treadles from the front and was glad of a small homemade cushion:
My old cushion - the phone book - is still in place at the back of the loom in case I have to squeeze in to make changes with the warp on the loom:
One last tweak, the beater was just catching the new uprights on the loom frame when it was swung back, a little foam cushioning does wonders:

This is the warp I put on the loom, it's for another colour sampler:

and bobbins - ready to weave, but that is a story for my next post. Bye for now!


Leigh said...

Very interesting post with good problem solving. I read about the balance of weight recently in one of Peggy Osterkamp's volumes, so what you did made sense to me.

Question - do you use locking pins in the countermarche while you tie up your treadles?

Geodyne said...

Dot, this is simply fabulous. I've often looked at my Glimakra and thought that there's space for more treadles (it's already been expanded from 8 to 10). I've also thought that there's space for more shafts. I have to say that I'm inspired.

The colours on the next sampler are simply fabulous! Can't wait to see what you do with them.

Dorothy said...

Leigh, about locking pins, I like to use locking pins BUT when you use them you can't see problems as they occur. If you have got a tie up method that's working nicely, as I had before adding the extra treadles, locking pins are useful as it's a bit quicker working with them in.

I used locking pins on my first tie-up attempt, which isn't shown in the photos, and got rather an uneven mess (lams all different levels).

So, I started again and the first b&w photo above, with the lams even heights, but yawning apart, was done without locking pins and using the box to support treadles until they were tied.

Geodyne, when I got these colours on the loom I realised they are going from autumn into sunset colours, I'd just add a pale celadon blue and a deep indigo purple to get the range of our sunset skies. I thought this was the dull set of colours (compared to the last sampler) but now they are on the loom I love them.

Catzee said...

Ya need kitty help wif all them strings.

Peg in South Carolina said...

Congratulations! Not that I had the slightest doubt--between your skills and your boyfriend...! Look at your loom, I have plenty of room to add more treadles, and, since it is a Jack loom, I don't think it would be nearly so difficult, thought the rear-hinging might create a problem. Perhaps I shall investigate? Some day? In any case, I am always blown away by what you do. I know that's really trite, but I mean it.

Dorothy said...

Catzee - Lil'Annie cat thinks just like you, which is why we have just spent 15 mins playing all around the house with Annie's very own bit of string - a lovely thick chewy cotton string with a fir cone tied on near the end! It's even more chewy than Texsolv heddles, but you know how it is if people ignore cats, and the lil' cat can't find the best string then there's always heddles and stuff to chew!

Dorothy said...

Peg, thanks for your comment. Only time will tell if I am to go on to produce beautiful weaving like your fine crackle samplers!

It's taken many months of thinking about loom alterations in the back of my mind before going ahead with this. However, I know the way I've written about it makes this look more like sudden inspiration.

I tend to turn bits of an idea over and over in my mind, then put them on one side, come back to them later, see if it makes sense, if not, look at it from another angle.

The starting point was wanting more weaving possibilities and then working out I didn't want any other loom except ones too big for my workshop (I read up on many makes and models!)

It helps that my loom was 2nd hand and well used, so I don't worry too much about changing it, and I haven't made any alteration that cannot be reversed.