Aquarium Airline Tubing for a Treadle Belt?

I regularly use treadle sewing machines. For years, it never occurred to me to use anything other than leather belts for them. They worked great with no issues for a long time.

But then I got more treadle sewing machines, and I needed more leather belts. I discovered that the quality of leather belts had gone way down. The last couple of leather belts I had purchased were terrible quality. Usable, but ugly, and too thin, and more likely to break. You can still get good ones a few places, but it’s hard to tell what you are getting when you purchase online. Often sellers will use a picture of a high-quality belt and send you something else.

I also was having problems with the belts slipping, which had not been a problem for me before, probably because I moved from a humid area to a drier climate. Someone on a vintage sewing machine forum (either Victorian Sweatshop Forum or Treadleon) said they conditioned their belts with leather conditioner to keep them from slipping. I happened to have some neatsfoot oil and beeswax, so I mixed up some leather conditioner, enthusiastically saturated all of my belts with it, and baked them in a warm oven just like I did when I treated my boots.

This ruined all of my treadle belts. I probably should have been a little more cautious and tested it on one first, huh? They did stop slipping…at first. But then they stretched, and stretched, and stretched. I couldn’t get through a single sewing session without having to shorten the belt. The lower quality belts stretched the most. Also, the belts were a greasy mess. I hung them up with weights tied to the ends for a few weeks to see if they would finish stretching, which may have fixed the problem, but then I discovered a better option, so I never actually tried using them again.

For you purists who only use leather belts, here’s a suggestion: If I were to try leather belts again, I would buy 1/4″ round leather belting from McMaster-Carr. They sell it for use on machinery, so I would expect that what they sell is better quality than the junk some people are marketing for treadle sewing machines. I would also mix up a thicker leather conditioner (maybe half beeswax, half neatsfoot oil), and use it sparingly, just on the outside of the belt.

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Right after I ruined all my leather belts, I happened across a suggestion to use aquarium airline tubing* as a treadle belt. I was really fed up with leather belts, and the tubing is inexpensive, so I decided to try it.

I love the aquarium airline tubing so much I’m not sure I will ever go back to using leather belts. The tubing is grippy, without having to be waxed or greased. Most importantly for me, it is just a little stretchy, so it works at a variety of tensions. This means I can use the same belt in a table and swap out different machines that need almost, but not quite, the same length belt. With a leather belt, you have to get the length exactly right. Even a half-inch difference in length is too much for a leather belt.

For me, the only drawback to aquarium airline tubing is that it continues stretching over time (although the stretching is a lot less after the initial break-in period). A good quality leather belt generally only needs to be shortened once after you install it. For me, the pros outweigh this one con, though. If you remember to remove the belt every time you quit using the machine, it helps a lot. I probably forget and leave the belt on the drive wheel about a quarter of the time. But it doesn’t really bother me to shorten my belt every now and then.

A couple of people have asked me how I join the ends of the tubing. Here is how I do it:

Put the tubing on your sewing machine to determine the length to cut it to. It stretches quite a bit at first, so go ahead and adjust it so it is pretty snug to begin with.

Next, punch holes in each end. I use a 1.5 mm leather punch* to punch holes about 3/8″ (1 cm) from each end of the tube. You could also drill a tiny hole, or just punch holes with an awl or needle. The advantage of the leather punch is that it makes round holes with smooth edges, which are less likely to tear and are easy to sew through.

Cut a short piece of tubing just long enough to fit between the holes.

Now cut that short piece in half lengthwise and insert it into one end of the tube. Having this bit of tubing inside helps support the stitches, so they are compressing the piece of inner tubing rather than just putting stress on the holes. It also holds the ends of the tube together while you stitch the ends together, which makes things easier.

Put the tubing on your sewing machine, and double-check that it is going through all of the right guides. Leave it hanging loose around the drive wheel so it is not under tension. Push the scrap of tubing into each end between the holes to hold it together.

Now you might want to triple check that the belt is going through all of the right guides, because it is time to sew the ends together. I use four strands of jeans topstitching thread. Don’t use upholstery thread; it is too slippery and the knot will not hold. You could probably just use more strands of all-purpose thread (or stitch through more times) if you don’t have any non-slippery heavy thread.

Sew through the ends of the tubing a few times, tie a knot, and you are good to go. I have in the past put fray-check on the knot, but I haven’t been lately, and have not had a problem with the knot coming undone. The tubing will stretch out quite a bit at first, and you will have to shorten it, but then the stretching slows down. Remember to remove your belt from the drive wheel when you are not using the machine, and you will not have to shorten the belt as often.

You can also sew the ends of leather belts together in a similar manner. I liked doing that so I didn’t hear the annoying tick-tick-tick of a staple going around the machine.

Happy Sewing!

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