I'd like to make a ratchet for the cloth beam on my CM loom. What's the diameter of, say, a Glimakra tensioner - the "donut" with a square hole and five spoke handles?

 

Thanks!

Comments

Wed, 10/30/2013 - 19:00

Telemorris

I'm nearing completion of the plans for my loom and have one odd question for the group...

 

I've noticed that the Glimakra Standard has not one but two ratchets per beam, cloth and warp. It got me to thinking about whether there's a real need for two ratchets so here are some questions...

 

1. Does either the warp beam or the cloth beam (or both) twist under tension when the beam(s) is locked at one end only? Have you ever had a problem with the tension at the end of the beam with the ratchet and pawl being tighter than the tension at the other end?

2. For those with Glimakra Standard looms or something similar with a ratchet on both ends of a beam, do you ever set the tension from one side then go to the other side to increase the tension there by a notch or two?

3. Is there a length of beam where this kind of tension adjustment becomes necessary? As in, beams up to 36"/48"/60" work fine setting the tension on one end only but over that you really need a pawl at both ends of each beam?

4. Is this only important for certain types of weaving - say, rug weaving where the tensions are higher, than for, say double weave, or whatever?

 

Thanks!

Wed, 10/30/2013 - 19:49

Sara von Tresckow

Up to about 48" weaving width, it is normal to have just one tension wheel per beam. On wider looms, torque can become a problem, especially when weaving rugs, so looms over 50" often have the second set of ratchet wheels. They work well, but on narrow goods, it is a pain to adjust both sides.

Thu, 10/31/2013 - 23:28

sandra.eberhar…

http://woodgears.ca/gear/index.html

This site offers inexpensive ($26) softwware for making gears.  You set the size of the axle, number and size of teeth.  You can make a gear train.  It will print a template for cutting the gear out.  I made one for my barn loom out of ash and it's great.  I have a 4' wide rug loom with one ratchet that is always set at very high tension and I never have problems with the beam twisting.  I have an 8' wide Leclerc with dual ratchets, and they are a nuisance, but I think needed.

Fri, 11/01/2013 - 08:16

ReedGuy

Keep your ratchet fins short and it will be stronger than high fins if your using wood. I've used this site before, posted in the previous post. I can't remember if it was that site or not, but I have seen a working mechanical clock made entirely of wood.

I weave 60" with one steel ratchet per roller, never an issue. Any issue that would arise would be holding strength of the wooden parts. Not just the wheel/ratchet, but the axil of the roller that the wheel is attached. That has to be well secured to the roller and be strong to take the turning forces.

Fri, 11/01/2013 - 08:41

kerstinfroberg

ratchets were often made from old circular saw blades.

This is what my cloth-beam ratchet looks like:

and the pawl:

Fri, 11/01/2013 - 10:18

ReedGuy

You can actually buy a brush saw blade with exactly the same profile as Kerstin's old blade. They are around CDN $25. But then it must be cut with a square or round hole depending on how you want to mount it, on the wheel or the shaft. Most folks would have to buy the blade and have it cut as there most likely are no saw blades lyng around in the shed. A table saw blade might be had, but if it's tipped those teeth are carbide, very hard and brittle when a metal pawl hits them with forces involved.