Machine Starts Fast, Then Slows To Normal

[hatcreek]

Hi All,

I have a Cobra model 17 that will sometimes start out with a really fast stitch speed and then slow to normal. I barely touch the pedal and slowly move it down then BAM! we are off and running. This will last about three to five stitches or so by the time I get my foot off the pedal (it is moving fast). Then when I try it again, it starts normal. It usually happens on the first stitch after I turn on the machine, but not always. Somedays it starts normal and I have no problems with it. I have the speed set to the lowest level.

It seems to be happening less frequently now that I have been using it more, but I am still nervous for that first rush, (images of Christine come to mind, pulling my hand into the needle my fingers permanetly attached to 4 ounce leather).

Is this something that I may be doing, or could this be a servo issue. I have only had this machine for about two months now. I have a Cobra 4 that this has never been an issue with.

Other than that, once we are going it sews great.

Any insight would be appreciated.

[Wizcrafts]

Please contact Steve Tayrien about your motor problem. His number is 866-962-9880. But, first try loosening the v-belt a bit. Sometimes, an overly tight drive belt will cause erratic motor behavior. In fact, you can test it by removing the belt entirely, then lightly push down on the toe of the speed pedal. See if you can run it slowly without any jumps in speed. If you get it set to a good slow speed position and hold it steady, but it speeds up without any further pushing on your part, the controller circuitry may be defective.

BTW: Is this motor the one with the digital readout and up and down speed buttons?

[hatcreek]

Please contact Steve Tayrien about your motor problem. His number is 866-962-9880. But, first try loosening the v-belt a bit. Sometimes, an overly tight drive belt will cause erratic motor behavior. In fact, you can test it by removing the belt entirely, then lightly push down on the toe of the speed pedal. See if you can run it slowly without any jumps in speed. If you get it set to a good slow speed position and hold it steady, but it speeds up without any further pushing on your part, the controller circuitry may be defective.

BTW: Is this motor the one with the digital readout and up and down speed buttons?

Thanks Wizcrafts, I will give Steve a call and see what he thinks. I will try the belt tonight to see what happens.

Yes, the motor is the digital model.

Thanks again,

Jim

[Wizcrafts]

One more adjustment you might try is to the rubber tipped stop screw that sets the minimum/off position for the foot pedal. There is a chain connecting the right side of the speed pedal to a small lever that protrudes from a slot in the back of the servo motor. There is a turn-able screw with a rubber cap than moves the lever. In the off position, the lever sits at the top of the slot. If this screw is set too far down, the motor will always be almost on. Try turning the screw all the way up, until it stops turning. If necessary, take off the rubber cap from it. This allows more upward motion, which translates into more off and low speed range of motion.

Also, make sure there is a little free play in the chain going from the pedal to the hole in the motor speed lever.