How to determine proper warp tension

Is there a general rule about warp tension?

Comments

Posted on Mon, 02/02/2015 - 01:48

If you mean, is there a formula? Not really

The warp should be tight enough it opens cleanly, firm enough to withstand a slight tug on the weft and go back to 'neutral' when the weft tug is complete. Different fibres will be happy with different degrees of tension. Weft faced rugs will require more than a wool, for example. Experiment while weaving the header, then try to adjust the tension as closely as possible each time you advance the warp while also learning to adjust the force at which you place the weft at the fell.

Weaving requires bio-mechanical feedback as you listen and feel what is happening with the loom, the yarn, and the weaver. The weaver is the one who gets to control what is happening by adjusting how to use the loom.

Cheers
Laura

Posted on Mon, 02/02/2015 - 01:48

If you mean, is there a formula? Not really

The warp should be tight enough it opens cleanly, firm enough to withstand a slight tug on the weft and go back to 'neutral' when the weft tug is complete. Different fibres will be happy with different degrees of tension. Weft faced rugs will require more than a wool, for example. Experiment while weaving the header, then try to adjust the tension as closely as possible each time you advance the warp while also learning to adjust the force at which you place the weft at the fell.

Weaving requires bio-mechanical feedback as you listen and feel what is happening with the loom, the yarn, and the weaver. The weaver is the one who gets to control what is happening by adjusting how to use the loom.

Cheers
Laura

Posted on Mon, 02/02/2015 - 13:45

I usually hang 8-20 oz. plastic water bottles off of bouts 2-3", varying the weight to the fiber. With this method, I know the warp has been beamed under consistent tension all the way across, and I won't hit soft spots when weaving, or places where the warp may overlap slighlty on itself under the packing paper.

Posted on Mon, 02/02/2015 - 15:30

Thanks Laura,

I have been weaving for less than a year and only a few months with the Macomber. After taking a basic weaving class I have been learning by trial and error, mostly error. Yesterday I started weaving a waffle weave hand towel that used four out of the five shafts to be rasied. The fifth shaft also rose about an inch. I started to put some kind of weight to hold it down when I realized that if I losen the tension it stayed down. So it got -me -to -thinking that I have been using to much tension all along. That is why I asked if there was some kind of guide line for setting the tension. This also my be why I'm having an uneven shed.

Don

Posted on Mon, 02/02/2015 - 17:44

Some looms will tolerate higher tension, such as a counter balanced loom, without having shafts rise, like on a jack style loom. Beginners frequently use too high or too loose tension. Or inconsistent tension. It's a learning curve, definitely. Sounds like you are making good observations and adjusting accordingly. :)

Cheers
Laura

Posted on Sun, 02/08/2015 - 00:38

is right. On a jack loom because of the dip when you overtigthen the warp everything wants to be pulled up. Adjust your tension so the warp threads sit on the bottom of the beater race and the shafts are not raising. The other thing is your beater may not be down enough. You can change the beater by using a different slot or by adjusting the cam. To adjust the cam lossen the bolt on the inside of the beater upright and push it down as far as it will go. Check the warp, it should still be sitting on the race with the beam as far down as it will go. This will give you the biggest shed.

Michael

 

Posted on Sun, 02/08/2015 - 13:04

Michael,

I've been playing with those adjustments and I think I have it set pretty close. I found that the cam is set higher on one side to even out the beater. Also I have to keep an eye on the left cam as it tends to loosen up. I am trying different warp tensions as Lura suggested. I don't have enough experence to know how it will effect the quality of the weave but so far it looks fine. With a looser warp tension I have to learn how to control the beater. Also I have to figure out how to keep the same tension when I advance the warp. Like I said I'm learning by trial and eror, mostly eror.

Don

Posted on Sun, 02/08/2015 - 03:35

the cams should be the same. If they are not you may have something out of sq. If you hold the castle and try moving it does it move. To check the beater, measure from the bottom of the castle cross piece to the beater race (not the top of the beater) this distance should be the same. On the casting attached to the castle there are two sets of holes, are both sides in the same position?  

Posted on Mon, 02/09/2015 - 00:14

Michael,

I checked to see if every thing is tight and does not move. I am not sure how to square the loom other then raising the left cam a half inch.
I put a four foot level across the beater base and I found it bows in the middle. Therefore the reed sits high in the middle, about 1/4 inch plus the 3/8 inch it sits out of the reed channel, leaving the warp to be over 1/2 inch above the race. Do you think I should regrove the reed channel to compensate for warped beater or leave it as is and weave?

Don

Posted on Mon, 02/09/2015 - 00:26

One other trick is to not place the shafts next to each other.  I don't know how many shafts you have or if it is too late for this section of warp, but on a Macomber you can easily remove the shafts not in use (or just not use them) and spread the needed ones out.  If you have 8 shafts  and only need 5 you can leave gaps.  This reduces sticking.

Posted on Mon, 02/09/2015 - 13:40

On Cheryl's 40/16 I notices that the shaft hooks are off set. I have see four holes on a number of Macomber heddle frames and didn't know why. Now I do.

Michael

Posted on Mon, 12/21/2015 - 00:55

Your help will be appreciated:

1.  Yarn Spinneries:  Especially to those of you in New England, USA, but the topic could be answered from and about any North American region:  

a.  What spinning mills are still in business, especially those spinning weaving yarns as opposed to knitting and "craft" yarns?  

b.  And if you know, which are spinning only woolen-spun, and which are spinning worsted-spun?  The equipment required at the mill scale differs.  Some mills may have the "tools" to put out both types of yarn.  

c.  Which are spinning rug yarns?

2.    Blanket yarns - their engineering:  

a.  Can a bulky single ply be used as a warp for weaving blankets?  If so, how many twists per inch should it have?  

b.  If not, can a bulky be plied to be made appropriate to use as a warp for weaving blankets?  The issues are tensile strength and resistance to abrasion of-by the reed.

3.  Mothproofing:  Since Mitin F Concentrate was lost from the market, is there any new permanent mothproofing agent that has taken its place?  

Thanks, Beaverly

 

 

Posted on Mon, 12/21/2015 - 01:12

I get worsted, hard spun warp from Honora Spinning in RI and buy their mill end yarn on Ebay (J&M Dyers).  I like  Bartett Yarns soft woolen sport weight yarn for thick lofty throws.  It works for warp and weft.