Technical sewinc machine for upholstery question on breaking top thread

I picked up a CONSEW sewing machine to do upholstery work on my 46 chevy 3/4 ton.

I can sew 3 layers of canvas (as test material) but every time I try for 4 layers the top thread breaks.
If I run it by hand everything is fine, tension is good, no problems

but at any speed at all, the thread frays and then breaks.

I have:
1) new needle size 18 (16 was recommended for this thread )
2) adjusted timing and hook distance to needle
3) tried 3 makes of upholstery thread
4) tried several different materials.

It is not the walking foot model (I wish it were)

any recommendations?

I hope to redo the bench seat.

 

Maybe you need a needle cooler. We have to use them at work on the heavier material.

 

Sounds like a timing issue but it could also be you just need a needle with a little larger eye. Thread gauge and needle eye need to work together. Cheep thread will give you grief. Could just be that it isn't a walking foot to keep fabric travel and needle speed in time with each other. Maybe loosen up your presser foot just a tad to help with the added 4th layer.

 

Call Ron at Quality Industrial Sew. 308-398-0383 He's been in the upholstery sewing machine business longer than anyone I know. I'm think he's a Consew dealer. I'm sure he will have a way to help you. Tell him Gary at Cornhusker sent you.

 

What size thread? I use 22 or 24 needles on everything and have for 50 years. With a smaller hole friction takes over

 

Make sure there are no burs on the thread guides. Take a very small file and smooth them out. If you can break the thread by pulling both ends(wrapped around your fingers), it`s not strong enough. It will rot on the roll.

 

Does the throat plate have a burr on it. You can feel it with your fingernail if it does. Also check your loopers with the machine turned OFF with your fingers for any burrs also. You can clean them up with fine sand paper or crocus? cloth...…….

 

PM Chip Quinn (need louvers ? ) here on the HAMB. He's a former sewing machine technician and can certainly be of help to you. Heck of a nice guy, too.

 

Chip hasn't been on the HAMB for about 6 months, he seems to be focusing more on other social media lately!