346 thread and 4500

[MADMAX22]

Would like to do some belts with 346 thread using my 4500. I have ran 277, 207, and 138 without issue. On the lighter stuff I would tighten the top tensions and back off on the presser foot pressure and it would do the 6oz (sometimes less) of upholstery leather. Normally back off on tension, increase presser foot pressure and go to town on 16-20oz belts or whatever. 

I put in the 346 natural bonded nylon thread and test stitched some 16oz of veg. It started wrapping up under neath and seemed to get stuck around the hook area. Actually stopped the machine while stitching slow. 

Generally speaking when going to this heavy thread what do you guys usually adjust to ensure good stitches. I would assume a 26 diamond point should be fine for this thread but could be totally off. The 25 works pretty good with 277 and the 24 with 207 in my experience. 

I noticed when putting the bobbin in the thread had a hard time going under the little "latch" (dont know the name) the little plate on the bobbin holder. 

Thanks for your input. 

[CowboyBob]

Yes ,a #26 is the correct size & when you thread it make sure you go around the 2nd tension 1 & 1/2x,Also you will probably need to tighten the upper tension for this 346 also.Also did you hold the needle thread for the first 3-4 stitches?

 

[JLSleather]

TIghten the top tension?  I would have thought maybe reduce bottom tension, due to increased diameter ...

 

[MADMAX22]

Got it thanks guys. Bob I have a good habit of holding the thread for the first few stitches. 

[Wizcrafts]

When I use #346 thread in my CB4500, I use a #26 needle, tighten the top tension and loosen the bobbin tension. Plus, I back off the two spring loaded screws holding the shuttle race in position. This allows the thicker than normal top thread to pass around both sides of the bobbin/shuttle assembly without binding/pinching. In effect, the thread pushes the shuttle to the left to allow it to go around. If the screws are too close to fully tight, the thread will bind on the way around.

[MADMAX22]

Good call Wiz Ill check that out as well. I think mine are only 1/4 turn out from tight. 

[Wizcrafts]

 

Good call Wiz Ill check that out as well. I think mine are only 1/4 turn out from tight. 

I have my screws backed off between 1/2 and 1 turn most of the time (1 turn for #346 thread). I only tighten them inward when using #92 or 138 thread. Then I back off to 1/4 turn. Also, keep oil inside the track in the shuttle race.

[MADMAX22]

Got it thanks Bob. Ill give all the suggestions a shot this night and try again. 

I usually put a couple of drops in the race before I sit down to start stitching, the whole machine gets oiled after every stitching session/ day of stitching. These machines tend to let ya know the race needs a few drops, they start getting a little more clunkety atleast mine does. 

[Singermania]

All of the above suggestions seem on the money to me, if after that you are still having some problems I'd go one larger in the needle to a 250/27.   Threads and needles can vary as well as machines, sometimes the thread is just too thick (no matter what its designated size or gauge) to fit in the long groove of the needle comfortably while sewing and can result in tangles and dropped stitches.