Setting the Sewing tensions on Singer 29u171a

[corkscrew]

Well I finally got my 29u171a Singer patcher machine. Having trouble getting it to feed the leather, stich and generally act right. This is my time using a machine and I have the manual and have read it thru several times now. Cleaned and oiled the machine per the manual. I have it threaded correctly, per the manual anyway. It's set up with 69 thread and a 29X4 needle. Doesn't want to pick up the bottom thread from the bobbin and when it does it bunches up in the bobbin and then stops. Also doesn't always feed leather along with the foot. I'm sure it's probably my in-experience in getting all the tensions right, but I'm getting a tad frustrated. Any pointers, ideas, suggestions would be appreciated! Thanks in advance.

[Wizcrafts]

I will take your word that the machine is threaded properly. But, are you using the proper needle system? I have seen patchers that had a needle that was too short and would never sew. You should be using either system 29x3, 29x4, 135x16, or 135x17. The scarf side of the needle must face due right and the ribbed side due left. Adjust as necessary and try sewing. If happy happy, rejoice. Otherwise, move on down.

That still leaves three other things that must be set right for proper sewing. Two of those affect the stitch quality and one determines if the machines sews or skips stitches. Later, I'll describe a fourth item. That's were you need to focus first.

If everything on the top is set as per factory specs and the hook is not picking off the thread loop, the hook timing is off. It is adjustable on your machine via a screwdriver hole in the right front of the lower section of the machine. Inside that hole, around the center of the base, there is an eccentric screw connecting a shaft coming down to a shaft running to the far left, through the cylinder arm. That eccentric retards or advances the hook to get the best timing. There is supposed to be a locking nut on the back of these coupled shafts. You will need to loosen that nut using the proper size box end wrench before the eccentric can be turned. Do so.

After loosening the lock nut, swing open the throat plate to expose the hook. Hold the top thread upfrom the needle, between the legs of the foot and hand wheel the needle down. When you reach BDC, slow down. Carefully watch the needle until it slightly raises up and halts, just before it starts back down. It is during this slight jog that the hook needs to intersect the loop that is formed by the jog motion. If the point of the hook has not reached, or has passed the loop before it starts back down, use a long, wide, flat blade screwdriver through the hole in the body to turn the eccentric screw until the hook does meet the needle while there is a noticeable loop. Hand tighten the locknut, raise the needle, close the throat plate and try sewing again. If it sews, tighten down that locknut and rejoice.

If the  hook has been timed correctly to the needle, but the thread loop dissolves so the hook can't pick it off, One of two common problems exists. One that is easy to fix if the flat spring on top of the take-up lever (trapeze) is too tight. There should be a thumb screw on top of the spring that you can back off until it stops pulling the thread loop up before the hook picks it off. If that doesn't get the loop back, the only thing left is the paddle shaped check spring inside the needle bar, which is either bent, worn out, or missing. It is an operation to replace and will take some time and skills.

[Darren Brosowski]

Before the major work I would just add that the needle clamp (the bottom of the needle bar) can be moved so make sure the needle is as close to the hook as possible without touching.

If the thread is jamming up that could cause the feed issues so work on one thing at a time.

Above all patience..........

[corkscrew]

Thanks Wiz and Darren, I'll recheck everything and proceed. Thanks again, Tom

[jimi]

just in case it still tangles underneath, that is what happened to my 29k171 and found that the shuttle race was the wrong size. the previous owner had fitted a new one which was too thick, thus not leaving enough room for the thread to pass under the needle plate causing the tangle up underneath. i changed it with a second hand simanco part and it work straight away.

Edited June 15, 2018 by jimi