Gymnast2

I have been using my using my Singer 201 and Singer 237 to sew a V138 thread in vinyl and webbing for some time now. A few simple modifications were needed to make the machines do that resonable well.

Normally you will see recommendations, that you should limit the thread size for all domestic machines to V69 (tex 70) thread. I think it is true mainly because of limited thread tension and limited punching power of the motor.

My Singer 201k have sewn about 2000 m of tex 135 thread now, and I have not seen any signs of wear. But I guess that you can expect the machine to be weared faster with the heavier load on it. But these vintage machines are in easy cheep supply in my country, and I am not that afraid to use some of them for heavier work.

I know that it may be easier to use an industrial sewing machine, but it is heavy and takes up space. Furthermore you do need to know what you are doing in both cases, and the consequences of a mistake can be costly for an industrial machine.

This is a video of my Singer 201k sewing tex 210 polyester thread in 6 layers of vinyl. In the last part of the video is a list of the modifications to it:

https://youtu.be/21D5S8ihspI

Mickey2

I guess there are lots of 15s, 66s and 201s around that can do a superb job in 2020. I have used Gütermann top stitch and extra strength threads in my machines, and slightly thicker threads of other brands with out problems. I haven't noticed any overload on my 201, it sews most materials nice and easy. Sewing layers of upholstery I have had tension problems but it was easily solved. I think these machines were made to take larger needle sizes. The last pages of my 201 manual shows a needle/thread indicating chart and it looks like Singer once made size 20 and 22 needles. I could only find them in a Chinese brand, but they did the job. Getting the larger shaft and groove in the neede solved any tension issues.

I can't recommend pushing these old mahcines beyond their limit, but they happily sew most types of upholstery, light polyester sail canvas, even bull denim (within reason). Anything that easily slide under the presser foo ist generally fine. You notice when motor and machine start to struggle and I avoid it. Among domestic machines, the old cast iron straight stitchers are in a league of their own.

Gymnast2

Thanks for your reply, Mickey. I have got similar experience.

I have used a range of needles from size 8/60 to 22/140 on my Singer 201k, Singer 66k and Singer 237 with no problem. I found no needle size specifications in the manual of the Singer 66. The manuals for both the Singer 201 and 237 specify needle sizes up to 21/130. The needle length from but to point vary with the needle size.

I have got a Bernina 910 as well, and the manual states needle sizes up to 18/110. I have tried to install a size 21/130 needle in it, but then something hits the needle. So for more reasons I would never try to use heavy thread with this machine.

For more layers of lighter canvas I have been able to balance the stitch with the normal beehive spring in tensioner and a size tex 135 thread. However with more dense fabrics of leather, vinyl and webbing I needed higher thread tension than the normal beehive springs of the tensioners can provide. If you try to squeeze the beehive spring, the thread tension becomes very unstable. So the right way here is to get a heavier beehive spring.

asleep

Hello @Gymnast2 , Thanks for those videos you posted about the singer 237 and sewing with heavy thread in heavy duty fabrics. I'm hoping you can advise on a few questions. I have one project in mind that I'm looking to do with my Singer 237. I am looking to use v92 polyester thread. The manual says it will accept a needle size up to an 18. The project I'm considering would require just over 100' of sewing and a max of going through 5 layers of vinyl awning fabric for half of that. I have considered that I may need to hand crank instead of relying on the motor to punch through all those layers.

Here are my questions:
1) Would the modifications you recommend be required for using v94 thread since this is merely 1 size up from the generally recommended? Or are there a critical few modifications that I would need to do, but maybe not all?
2) Do the modifications need to be reversed after the heavy duty project for general purpose use?

Once again. Thanks for all your information. Your post has given me hope that I will be able to do this project with my existing equipment.

Gymnast2

For a V92 polyester thread and this application, then I would prefer a thicker needle that a size 18/110 like size 19, 20 or 21. In my Singer 237 manual is stated needles up to size 21, and I have used size 22 with no problem. How thick are the five layers of vinyl you intent to sew? You may encounter problems if the thickness of firm fabric increases 5 mm, because of the feed timing, and you cannot adjust that.

My best guess would be, that you need to have a stronger beehive spring in the tensioner. You can easily switch the old back. If you get problems with damaged thread, then you most likely need to modify the shuttle hook, so you get a a smooth thread U-turn near the hook. This will only make the maschine better for thinner threads too.