Returning Ground Shafts to Neutral on the Drawloom

[@cbritten]

I am so with you on counterweights for all drawlooms. I would go even further to say counterweights for all shafts (not just 6) for all countermarch looms. I just finished a huck sampler on my 8S Ideal (horizontal countermarch) and made good use of the buttonhole elastic "shaft bras" on two of the shafts. I would have preferred to have had counterweights, because for one thing I also had one rising shaft. And I completely agree that it would be preferable to have proper weights for the setup rather than sandbags.

[@saraclevering1419]

Great video, in particular as i have struggled with this. One question--if you have the option to put elastics on your lamms or on the shafts, why do you prefer putting elastics on the lamms? I haven't tried that yet. Also, i've seen pictures of looms with the counterweights--thanks for explaining "what the heck that is".

[@DuellingRabbits]

I guess because I can? I find it easier to work away from all the cords cluttering up the real estate over the beater. I also like the idea that we are working with the lamms rather than against them - I don't think it's my imagination that the system balances more easily and with less effort that way.

[@Anna-qx6hu]

This was an interesting video. Thanks. I have weights on my single unit horizontal countermarch loom. However for some reason the shafts don’t snap back. They used to but I took my drawloom attachment down to weave a rug. Now I’ve put the attachment back and the shafts don’t do what they used to. I don’t know what I did wrong.

[@DuellingRabbits]

Oh dear - I wonder if the weights are rigged to the jacks correctly? I have a diagram somewhere - e-mail me if you'd like a copy.

[@chrisking9245]

Could I use the Julia 8 shaft countermarch loom as a four shaft counter balance loom. Thank you

[@DuellingRabbits]

You sure can! I believe the first Julia's were designed in exactly this way.

[@skullzandbonez100]

I have to admit, while this video is very informative, I still find the whole mechanics confusing. For example you demonstrate that without some kind of restoring force the jacks do not return to neutral but it’s unclear to me why that’s the case. I fundamentally don’t understand why the whole heddle assembly doesn’t immediately proceed to one of its polar positions (ie, how do the jacks remain neutral) when no restoring force is applied as shown @ 2:20. Unless the torque applied on the jacks by the lower lamms is equal to the opposing torque applied on the jacks by the shafts and upper lamms, the jacks should proceed to one position or another. Perhaps the friction in the jacks’ pivot points and the pulleys are sufficient to maintain the shafts in their final position? Perhaps the jacks are uneven and have greater weight on the bottom? While I understand how the elastics and weights can return the jacks to neutral, could you explain the following to me in further detail: When no restoring force is applied (as shown in 2:20) how is it that the shafts can exist at neutral? Why don’t the shafts rapidly proceed to one of their extreme positions (fully raised, or fully lowered)? Surely the torque on the jacks is not *perfectly* balanced. Why don’t the shafts “not budge from their previous positions”.

[@DuellingRabbits]

So ... inertia I think? I have never really thought about it in the terms you describe, but I am going to go out on a limb and posit that the CM jacks are not balanced against the weight of the lamms and treadles. Even on a single-harness loom, a new treadle must be pressed to clear the previous shed. There is no inherent 'balance' in the coupers/CM jacks: on a vertical countermarch, the pivot point isn't even in the center. All the engineering is geared towards overcoming gravity and the tension of the warp - so that when lamms are down (even when they are raising shafts) they tend to stay down if they are heavy enough (new Standard looms have longer lower lamms for this very reason). Add the fact that on a drawloom not every shaft is in motion for each pick and it is easy to see how the problem can compound. I agree that any shaft at neutral tends to stay at neutral - but that is only the case until it is first called into service. Does that make sense? Does it answer your question? Thank you for the thought experiment!