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Frequently Asked Questions

Troubleshooting Tension

Depending upon the type of loom, tension may refer to separate warp and cloth tensions, or a combined warp/cloth tension. The distinguishing mechanism between these is AVL's unique "sticky" beam. If your loom has a stick beam, the loom will have separate warp and cloth tensions and tensioning systems.

If you need to troubleshoot your cloth tension, visit the next section, Troubleshooting Cloth System.

Warp tension is established with either of three mechanisms: the Tension Arm assembly, the slipping brake tensioning system and the locking brake tensioning system. The Tension Arm assembly and the slipping brake tensioning system are both forms of automatic tensioners. While the slipping brake system is smaller and simpler, it also tends to be more difficult to tune and keep in tune. Not all AVL looms can accomodate a Tension Arm assembly.

If you look at the Tension Arm assembly, you'll note that it consists of an arm, on which slides a weight; and a cable which travels over a plywood pulley, to a large wooden drum on your Warp Beam, and finally to an anchor bolt on the loom frame. Worked into this cable is a loopy set of cords with a plastic lock. This is the Tension Tie-Up Adjusting Assembly. In contrast, the slipping brake tensioner eliminates all but the Tension Tie-Up Adjusting Assembly.

There are two things you need to understand in order to use these systems to their best advantage. On the Tension Arm assembly, warp tension is established with the weight and is maintained with the tie-up. On the slipping brake system, both are done with the tie-up.

As an analogy, think of tying your shoes. When you make that first cross of laces and snug them up, you are establishing tension. If you like your shoes tight, you'll pull harder on the laces. At that point, you've set your tension. But, if you were to simply walk off without finishing the knot, you'd spend the rest of the day re-snugging your laces. But instead you'll tie a bow - this will maintain the tension you put in the laces. So with the Tension Arm Assembly. The weight does what that first part of a bow knot does - it lets you set tension. The tie-up does what the finish knot does, it keeps the tension constant.

Optimal Performance: If your tension system is working properly,

 

Check out the following common causes and solutions:

Your Warp Beam just won't hold tension, the arm is down -- doesn't matter where your weight is or how tightly you've adjusted the cord, you just can't get enough tension.

Possible Cause How to fix it
1) Your Tension Tie-Up has loosened. Re-adjust the tie-up and either tie a bow in the cord ends or bind it tightly with a double wrap of cord.

2) You have mis-routed your brake cable. If you have just installed the system, disconnected your Brake Cable, to move the loom, or warp the beam, you may very well have incorrectly replaced it.

Review the cable routing as shown in the appropriate figure in the Assembly Section of your manual. Be careful, though, there are different illustrations depending on whether your beam is in the upper or lower position.

3) You may have warped your beam backwards. Go to your manual and consult that figure in the Weaving Section which illustrates how your warp should be routed.

If you did warp your beam backwards, you will need to reverse your tension cable. Unhook the buckle, loosen the cable, and wind it in the opposite direction. This is not a permanent fix. Use it only to weave off the warp you wound backwards.

4) The sandpaper on your Cloth Beam is not grabbing the warp and pulling it around as it should.

Check the first symptom listed under Troubleshooting Cloth Storage System. If the warp still won't adhere to the Cloth Beam, you'll very likely need to add SoftGrip or another kind of beam cover in order to get satisfactory warp tension.

5) The surface of the Brake Drum has become polished and no longer offers sufficient friction to grab and hold the Brake Cable.

Disconnect and unwind the Brake Cable. Lightly sand the surface of the groove in the Brake Drum with your #220 sandpaper. Replace the cable (but be sure about its routing!)

AVL Looms

The tension arm rises to a steep upward angle when you advance.

Possible Cause How to fix it
Your tie-up is too tight. Loosen your tie-up.

AVL Looms

AVL Looms

The Tension Arm periodically rises and then lets go, Wham!

Possible Cause How to fix it
This is a clear indication that the wood grain in the groove of the Brake Drum has become swollen. If you've had a recent elevation in humidity, it's almost surely the case. The grain has become so sticky that it won't let the cable slide smoothly over the drum. Remove the Brake Cable and sand the raised grain with #220 sandpaper until it is again smooth to the touch. There will be two places on the drum in particular that need attention; these are where the end-grain is exposed and will be opposite one another.

AVL Looms

Excessive tension on the warp.

Possible Cause How to fix it
1) Weight on the tension arm is in a too far out position Adjust the position of your weight on the tension arm.

2) Too much weight on the tension arm.

Use a smaller weight on the tension arm.

3) The tension rope has gotten crossed over itself on the warp beam brake drum.

Straighten out the rope.

AVL Looms