Using the Stitching Feature

Why Stitching?

You may need to stitch shorter parts together in order for the parts to successfully pass through a roll former. Short parts may partially or completely fall down inside between roll passes, which can cause damage to the part and possibly jam up the roll former.

Without stitching, operators have to modify the order to double part lengths and then cut them down later. This results in orders that never get marked “completed” in Eclipse. Another approach is that the order would have the part lengths doubled in Eclipse, but someone needs to remember to do it and can easily forget.

Having a stitching feature prevents the Customer Service/Data Entry/Sales person from worrying about what length of parts can be produced. The order entered into Eclipse can reflect the actual order the customer placed and the XL series controller will automatically take care of the issue for them. Since the XL series controller uses stitching, orders in Eclipse always get marked complete.

Do I have Stitching?

If you have either of the following Setup Parameters, you have the Stitching feature:

  • Stitch Gag
  • Max Auto Stitch Length

Stitching Methods

Half Cut

Some machines have the ability to do a partial cut so that parts can be separated later, after the roll forming process. A Stitch Gag is used to control this partial cut.

Omitting Cuts

If your machine is unable to do a Half Cut to stitch parts together, you can leave parts that need stitching joined together with other parts by omitting (removing) a cut. These parts can then be cut down manually to the correct length in a post-roll forming step.

Stitching Algorithm

Three different Stitching Algorithms have been developed and evolved as our customers have made requests for improvements.

Stitch Gag Original

If the controller has gags and the Stitch Gag parameter, this algorithm can be used. To use this algorithm:

  • The Stitch Gag parameter will be a non-zero value.
  • The Min Auto Stitch Length parameter will be set to zero.
  • The Max Auto Stitch Length parameter will be a non-zero value.

Parts shorter than the Max Auto Stitch Length will be stitched by doing a Half Cut with the Stitch Gag until the resulting blank exceeds the Max Auto Stitch Length parameters.

Stitch Gag New

If the controller has gags and the Stitch Gag parameter, this algorithm can be used. To use this algorithm:

  • The Stitch Gag parameter will be a non-zero value.
  • The Min Auto Stitch Length parameter will be a non-zero value.
  • The Max Auto Stitch Length parameter will be a non-zero value.

This algorithm provides more control over the resulting blank length, allowing more parts to be stitched together in one blank.

Parts shorter than Min Auto Stitch Length will be stitched together by doing a Half Cut with the Stitch Gag until the resulting blank would exceed the Max Auto Stitch Length and then a full cut is executed.

Stitch by Combining Parts (Omitting Cuts)

If the controller does not have gags but has the Max Auto Stitch Length parameter, this algorithm can be used. To use this algorithm:

  • The Min Auto Stitch Length parameter will be a non-zero value.
  • The Max Auto Stitch Length parameter will be a non-zero value.

Parts shorter than Min Auto Stitch Length will be stitched together by Omitting Cuts until the resulting blank would exceed the Max Auto Stitch Length and then a full cut is executed.

Stitching Parameters

Minimally, you must have one or both of the two parameters described in the Do I Have Stitching section in order for any of the other parameters to be available.

Stitch Gag

This parameter tells the controller whether you want to stitch by telling it which gag output, non-zero, controls the Half Cut shear.

Min Auto Stitch Length

Parts shorter than or equal to this parameter will get stitched. They will continue to get stitched unless the resulting stitched blank would exceed the Max Auto Stitch Length parameter. If Min Auto Stitch Length is non-zero, Max Auto Stitch Length must also be non-zero before any stitching will occur and Max Auto Stitch Length must be larger than Min Auto Stitch Length.

Max Auto Stitch Length

This parameter is used differently depending on the Stitching Algorithm that is being used. A description of how the parameter is used can be found under the appropriate Stitching Algorithm description.

Min Auto Stitch Leader Length

This parameter is only available for the Half Cut method. It is only used when in the Stitch Gag New algorithm. If the first part to be stitched is less than the Min Auto Stitch Leader Length, a scrap part will be inserted first to support the leading edge through the roll former.

Min Auto Stitch Trailer Length

This parameter is only available for the Half Cut method. It is only used when in the Stitch Gag New algorithm. If the last part to be stitched is less than the Min Auto Stitch Trailer Length, a scrap part will be added to the end to support the trailing edge through the roll former.

Stitch Mode

This parameter has four settings:

Never Separate

The controller makes no attempt to separate Orders, Items, or Bundles. No scrap will be added to do so. It will be the operator’s responsibility to make more parts or manually shear the blank if conditions occur that require separation, like running out of orders.

Order Separation

The controller will not stitch parts from different Orders together. If an order change is detected, the controller will stitch on a piece of scrap to the end of the last part within the order, if required. Scrap will be added to bring the stitched blank up to the minimum blank size required by the Stitching Algorithm.

Bundle Separation

The controller will not stitch parts from two different Bundles together. If a bundle change is detected, the controller will stitch on a piece of scrap to the end of the last part within the bundle, if required. Scrap will be added to bring the stitched blank up to the minimum blank size required by the Stitching Algorithm.

Item Separation

The controller will not stitch parts from two different items together. If an item change is detected, the controller will stitch on a piece of scrap to the end of the last part within an item, if required. Scrap will be added to bring the stitched blank up to the minimum blank size required by the Stitching Algorithm.