Doing things people say you can’t do.
I’ve been trying out the Pfaff 30 over the last couple of days.
I spent some time last night figuring out the minimum thread tension. My daughter’s Pfaff 31 can work reliably down to about 25 grams of thread tension. My Adler 8 needs at least 35 grams. The Pfaff 30 is right in the middle at 30 grams. I’ve adjusted the bobbin case on this Pfaff 30 to about 30 grams when using the finest thread my wife had available. That will let the new owner use just about any thread without adjusting the bobbin case.
I also practiced working the treadle. I’m not good at it yet, and I doubt I’ll get enough practice before I have to give the Pfaff 30 to its new owner.
It does sew well - and quietly.
Sometimes I think my biggest problem in learning how to operate the treadle is that I’m usually trying to film things at the same time. I’m not quite coordinated enough to do three things at once.
At any rate, the Pfaff 30 is clean and adjusted, so I thought I’d try to do something with it for real - and dispel a bad rumor while I’m at it.
I’ve seen several places on the internet where people have asked if they could sew leather with a Pfaff 30. The usual answer is “No! It’ll ruin the machine! It’s only a domestic, don’t do that!”
The fact is that the German Pfaff 30 user’s guide straight up says you can sew leather on it.
|Needle selection chart|
Underlined in red is “Feinleder, Plastik” - that’s “fine leather, plastic.”
Further down underlined in blue is “Segeltuch, Leder, Sackleinen” - that’s “sailcloth, leather, sackcloth.”
The Germans expected you to handle some pretty tough stuff with the Pfaff 30.
The English version of the Pfaff 30 user’s guide doesn’t explicitly say you can do leather, but it does mention sailcloth:
|Needle selection chart - English|
Underlined in red is “sailcloth, upholstery.” That looks to me like it’s right in line with the leather stuff mentioned in the German version.
I decided to make a small project with leather to try out the Pfaff 30.
My wife has a nice pair of embroidery scissors that she uses to cut thread while sewing - and that I keep swiping to use when I’m sewing.
I’m going to make a sheath for the embroidery scissors - and I’m going to make it out of leather.
I sketched out a pattern in Inkscape and printed it out. The idea is to sew the edges over so that there’s a smooth surface around the outside, then fold it in half and sew the long side shut to make a triangle shaped pouch.
The picture is (of course) after I’d already cut the leather and begun cutting the corners so that the seams lay flat around the outside.
|Sewing the edges|
The pieces I cut off the corners are kind of like mitering in wood work. The mitered corners let the folded over edges lay flat.
With the edges rounded off and sewn flat, all that’s left is to sew the long edge to make the pouch.
The last seam went through four layers of leather - a total of about 4.5mm (about 3/16 of an inch.) It didn’t slow the machine down at all, nor did it have to work hard.
Over to the right is a sign that things didn’t go perfectly well, though.
- Leather tends to stick to metal - the feed dogs had a hard time moving the leather under the presser foot.
- The presser foot can’t easily move over changes in thickness. Thick to thin is OK. Thin to thick stalls the transport.
The result of those two effects is that leather doesn’t feed well.
I knew that before I started - that’s why I did my best to make all the seams lay flat. I started sewing that last seam from the wrong end (from the right,) though, so that the feed dogs had a hard time moving the leather for the first centimeter or so. It is sewn, it’s just that there’s a thick, hard pile up of thread on the back side.
I had ordered a roller foot that I thought would fit, but when it got here I found it wasn’t low shank like I thought - it’s too tall to fit the Pfaff 30. I won’t have time to get a low shank roller foot before the Pfaff 30 has to go to its new owner.
To make it clear: You can sew leather with a Pfaff 30 (and the 31 as well.)
- You need a roller foot or teflon foot so the leather doesn’t stick to the foot.
- You need to plan your seams and corners so that you always sew from thicker to thinner so that the presser foot doesn’t have to try to “climb a mountain.”
- You’ll have to adjust the presser foot pressure.
- You need a proper leather sewing needle and thread (don’t use cotton.)
Those points apply to most vintage sewing machines, as well. The old machines were made of metal, through and through. Sewing leather doesn’t bother them - it won’t wear them out or break anything.
Modern machines have gears that are often made of plastic - the additional pressure it takes to punch through leather will wear the teeth right off the gears.
The Pfaff 30 has exactly three parts that aren’t made of metal:
- The leather drive belt.
- The rubber bobbin winder tire.
- The plastic knob that lowers the feed dogs for darning.
None of those can be damaged by working with leather.
One of these days when I’ve got the new motor controller for the Adler 8 finished, I’ll write up a description of what it takes to sew leather on a standard (vintage) sewing machine.
For my next post, I’ll see if I can do some darning with the Pfaff 30.