WIChix

Here is a service manual.
https://www.manualslib.com/manual/17...66-Series.html
I wouldn't rule out that something in the stitch length linkage is not fully free yet. These machines are pretty dependable. As long as Igor hasn't roughed then up, a good cleaning and fresh oil do wonders.

OurWorkbench

I have tested stitches with doubled Bounty paper towels.


There is a pin that goes through the tension assembly. Sometimes it gets gunked up. It is supposed to push the discs apart when you raise the presser foot and the discs will close together when the foot is down. (at least that is what it is supposed to do ) You should always have the presser foot up when you thread the machine, so that the thread goes between the discs. It could be put together wrong. WIChix gave you the link for a service manual, which shows the schematic of how the tension assembly is to go together. I have some small brushes that can clean small places. Should you decide to take it apart, be sure that the metal pieces are cleaned and polished smooth.


You said that the feed dogs move when you move the lever, was that when the needle plate was on or off? When I looked an my 99 clone, the feed dogs came almost to the front of the holes in the needle plate when I moved the lever to the longest stitch.


Janey - Neat people never make the exciting discoveries I do.

Thumbs

Thanks again

cant say to much about the spring tensioner yet. The spring I think is wonky is behind the faceplate in the head of the machine where the mechanic for the needle are. I would think it is supposed to push against the tensioner to open the tension disks. It’s is not sitting flat on the tensioner.
Yes when I move the lever the dogs change the length they move with the plate on or off. The dogs do come pretty close to the front of the plate opening.

WIChix

When oil and patience don't work...

Try a hair dryer to deliver heat to each of the likely (metal only) junctions in the stitch length mechanism path, turning the handwheel while heating up the parts. I would be tempted, then, after turning off the hair drier, to follow up with a chaser drop of oil at each joint/part of the mechanism that turns, rotates, slides, revolves, swings, etc. Keep turning that handwheel while you do so.

Thumbs

Thanks. Worth a try. I have put pressure on the joints I can get to while turning the hand wheel to see if something is just a bit stiff. Nothing I can see appears to be bent or damaged. Everything moves smoothly without an by hitches. I’ll try just a bit of heat to see if any gook or varnish is holding things up.
thanks.

Thumbs

Well no luck so far. Still can’t increase the stitch length at all. Just the same as when I started.

JoeJr

Have you checked the height of the feed dogs relative to the needle plate when the needle bar is all the way up? With the needle plate securely attached and eye level with the needle plate, hand cycle the machine and see if the dogs are coming up enough. I had a machine which would only make short stitches and this was the problem. There should be a single screw holding the feed dogs, if it's adjustable as I think it is, don't make them too high or they can hit the needle plate, test by adjusting then cycling the machine with the needle plate in place but not screwed down and see if the dogs lift the plate when they come up.

Thumbs

Thanks I will check. I know the material will pull through even when I am not touching the material. Also the dogs do come close to the front of the plate but not as close in the rear. The length of movement of the dogs does change when moving the lever but I can only get the stitch length down to 15 stitches per inch. No where near 6 stitches per inch. I can increase the stitches to almost on top of each other but can’t lengthen the stitch length down to 6 stitches per inch.

JoeJr

I would also want to make sure the feed dogs are level as well. I don't remember reading through the posts, but I saw you were originally sewing on felt material. If you haven't done so try something else.

OurWorkbench

When I looked at my 99 clone machine, the feed dogs came to about 1/16" from the front and the back when the stitch length was at the longest "6" stitch length.

I'm going to suggest these links again. I also found 99K adjustments

Janey - Neat people never make the exciting discoveries I do.