This problem deals with long inconsistent stitches with the chosen stitch length–not skipped stitches. To verify that the problem is related to your stitch regulator and is not a timing issue, try your machine in the manual sewing mode. If it skips stitches in BOTH modes, then start by checking the timing on your machine.
If it only happens when using the stitch regulator, then review these suggested remedies:
- Clean the wheels (most importantly the wheels by the black encoder boxes, as well as the little black encoder wheel extending into the wheels). For “M & M” polymer hard plastic wheels, wipe the inside of each wheel with a clean cloth or piece of scrap batting. Your aluminum rails and carriage will go through a natural oxidation process that produces black residue. That residue collects on the rails and inside the wheels. Keep the wheels free of this build-up by wiping them out often. If your wheels are older Ralmark wheels (they may be brown or black and look like sturdy pressed particle board), clean the inside of the wheels with a soft cloth dipped in rubbing alcohol. For both wheel types, also wipe the aluminum rails frequently with rubbing alcohol and a soft cloth to remove oxidation. It is no longer necessary to wax the rails.
- Determine if the skipped or missing stitches only happen in one direction by moving the machine vertically only, and then horizontally only. In most cases only one encoder may need adjustment. If the missing stitches happen when moving the machine forward and backward (vertically), the encoder wheel attached to the sewing head should be checked. But if the skipped stitches happen in the horizontal direction, then the carriage encoder wheel needs attention.
- Download pdf instructions to make adjustments to the appropriate encorde wheel. At some point your encoder wheel may wear down so much that it will require replacement. This is necessary when the shaft of the encoder wheel starts to rub on the edge of the larger wheel, or when you can no longer move it in enough to make good contact with the large wheel. The rubber wheel should always make good contact with the larger wheel. To test it, hold the large wheel steady with one hand and then try to turn the rubber wheel with your other hand. You should feel resistance between them, and may even hear a “squeak” to signify that they are indeed rubbing against one another.
- Be sure the adjusting cams on standard aluminum alloy tables have not worked loose, allowing the wheels to slide out of position. That will cause the black encoder wheel to slip and create inconsistent stitch length. Download pdf instructions to properly set the adjusting cams on the wheels of standard table models.
- Try not to put excess weight on the front handles as you are using the machine. This can cause the back end to raise up slightly, and could make the encoder misread your movements. This is especially important with vertical wheel machines. Use a light touch with accessories such as extended bases and guide rulers.
- Check wiring connections. On machines built after 2008, the wires connecting your encoder boxes to the sewing head plug into jacks on the machine. Look for the jacks labeled “head encoder” and “carriage encoder” and unplug the cables from the jacks. Then reinsert them and test the machine again. Machines built prior to 2008 will have connectors that looks like white plastic plugs. These connectors are called “molex” connectors. If you look closely you will see that the connector has a male and female end where the connector attached to one wire slips inside the connector on the other wire. Grasp the portion of the connector that is on the inside with one hand, and then grab the portion that is on the outside with the other hand. Pull the connectors apart. Examine the connector ends to make sure the pins and sockets inside them appear straight. Reconnect the molex connectors and try the machine again.
- It is possible that the wire that connects the black encoder box to the sewing head is damaged. Examine the wires along their entire length, starting at the encoder box. If you notice a worn spot, a loose wire or anything else suspicious with the wire, contact us for information about replacing it.
If you still have a problem, contact us at 800.426.7233.