This is an Artisan class machine, meaning one that was likely used in a small business such as a tailoring or dressmaking shop. It's for light- and medium-duty material and having given it a first cleaning, the machine probably sewed quite a bit of wool suiting. It's in good shape for an allotment year of 1912 and I particularly like that Singer thought it necessary to decorate even a mid-range industrial with rather beautiful decals. It has a motor boss but this was probably treadled and that's exactly what I plan for it.
Turning the hand wheel, it's very smooth and easy but something isn't quite right, as it makes a bit of a whine. There was (and still is) quite a bit of old oil to clean out and I'll need a set of presser feet and a number of needle sizes in addition to the aforementioned bobbin case, not to mention a somewhat bent spool pin. I'm thinking I could probably retrofit a butcher block countertop that some young, striving couple thought at one time might make a great kitchen accent. Or perhaps I could have a solid door cut down. I would then ask Steve or Nate (contractor buddies of mine) to cut out a hole for the machine and attach a set of treadle irons. The head came with a brand new belt still in its package.
You all know me pretty well as a mid-century type of guy who likes the power of high amperages and clutch motors. And here I am treadling. Weird! My friend Janet calls it 'the dark side.' I've no doubt she meant it figuratively but I suppose that's literally true, especially in a power outage.
I hope you are doing your leg-strengthening exercises for all those treadles you have acquired recently.
ReplyDeleteOne thing that kind of surprises me is the size of the hand wheel. It's not one of those big heavy one that one usually finds on treadle machines to provide a lot of momentum. But perhaps other features of this machine makes that less necessary?
Exercises and coordination! I'm surprised how well the drawing room cabinet treadle mechanism works -- just smooth as anything.
DeleteAs to your question, it's been so many years since I took physics! If the diameter of a wheel (say, at a motor pulley) is smaller, the speed is slower and the force is greater. This is one way to tweak an industrial setup for heavier material. But there are other factors such as mass, so this only a very general principle. (Solid metal vs. spoked vs. Bakelite, etc.) Your observation is a good one, as a difference in diameter will affect force and speed -- if the treadle wheel itself remains roughly the same size (at the pedal), a smaller diameter wheel at the main shaft will probably exert larger force at the needle. It's similar to a bicycle, if that makes sense: pedals of a certain diameter from the center turn a larger wheel activating a chain to a smaller diameter resulting in greater force to the outer back tire diameter. Shifting gears shifts the chain to larger or smaller diameters depending upon the desired force at the point of friction.
There are probably some old English scientific journals or diagrams that can explain this much more thoroughly. I should do some research on this. In looking at pictures of this machine and the 31-15 (much more common, I'm guessing from the number of pictures), this head was motorized as much as it was treadled.
I guess I am thinking of it in terms of my spinning wheels. My production wheel has a 32" diameter, which is huge relative to most other designs. It is effortless to get started, to treadle, and to keep going because the wheel is so big, which is a plus when spinning for long periods of time. However, unless one is sewing long seams, I am not sure that is a required feature of a treadle machine. I am still surprised, though, at how much smaller and more delicate that hand wheel is compared to the two treadles I have, because it was always my understanding that the larger hand wheel with more mass was desirable for treadling as it took less effort to get started and keep going--similar to a spinning wheel.
ReplyDeleteThere are many factors at work and it's been so long since I've studied anything similar that I'm probably getting something wrong but if you think of a bicycle being two equations, the left and right sides must be equivalent, i.e. Force must be equivalent to the combination of resultant factors (friction, internal resistance, diameter, mass, gravity, etc.). The same principle is true re. sewing machines: for example, if the hand wheel is achieving zero acceleration (constant velocity), then a simplified equation can pretty accurately describe what it needs to be maintained.
DeleteAs to diameter, I'm not sure it matters much in spinning except in maintaining a constant velocity so that the operator can predict the amount of fibers needed to create a consistent combination of strands. (I'm totally guessing here -- feel free to laugh!) For a sewing machine and especially an industrial one, a smaller wheel at constant velocity produces greater force but the principle of the equation remains: is the hand wheel solid, metal, spoked? Other factors include angle, friction, and tension of the cord, diameter at the pedal, balance and diameter of the treadle wheel itself, etc.
So to your point, diameter and mass are but two factors in putting into and maintaining the motion of a sympathetic wheel and they can vary widely depending upon other factors. In your spinning wheel example, a larger diameter means that the cord has longer/greater friction at contact.
I'll try to do some research on this and come up with a more scientific answer. The good news is that all of this does make sense, i.e there are equations that describe all of this behavior! I just have to find them. I know a really bright mathematician and I might get together with him and ask him about it.
I'm trying not beat a dead horse here; you and I may be saying the same thing but I think you're overthinking what I am saying. I may need to introduce you to my spinning wheel and how it works. It's actually a double drive system; the belt wraps around the large wheel twice and around the bobbin wheel twice, as well, and the variety of combinations of diameters of the bobbin wheel and large wheel allow for fine variations in the amount of twist that gets put into a strand of yarn. For example, a small bobbin wheel will revolve more times per revolution of the large wheel and thus put more twist into the strand of yarn. A larger bobbin wheel revolves fewer times and thus puts less twist into the strand of yarn. So yes, the diameter of the large wheel matters greatly, which is why my production wheel has a 32" diameter. A spinning wheel with a 15" diameter, for example, is going to require lots more treadling effort to put the same amount of twist into the yarn as my wheel.
ReplyDeleteI am also thinking about the video I watched the other night where a woman was using a treadle machine for free motion quilting. She noted that because there were no feed dogs to pull the fabric through (that's the "free motion" part), she had to start off treadling as fast as she could. There was no working up to speed as there might have been if she were just sewing a plain seam. In that instance, I would think that having a heavier hand wheel would be a plus as it would allow her to get going and keep going much more easily. Have you treadled on either of your machines yet? As experienced a spinner as I am, it still takes a bit of work and even I had the problem of the wheel going backwards once or twice before I got the hang of it.
I don't need the equations, so don't go to that much work. I was just making an observation about the different sizes of hand wheels and how they affected treadling. :)
I'm interested in achieving a better understanding of it anyway, so I'll probably do some research and I might even post what I've been able to figure out. Your spinning wheel has a lot of friction, as it's double-wrapped. The point I was trying to make (and not doing it very well) is that every variable will affect the equation, whether you're solving for velocity, force, inertia, etc. And there are scientific factors as well as practical ones such as exercising our ankles and calves in order to exert enough force to start, increase, and maintain the desired speed to sew or spin.
DeleteI agree with you that a heavier hand wheel (greater mass) means an increase in inertia, meaning that wheel would more easily maintain a certain speed or range of speeds. But it would require greater force to reach that range and would take more force to stop (gravity over time, for example). So a wheel with less mass has greater control, if by control we mean less force required to reach the desired speed whether at F = v or v = 0. A machine (treadled or not) with a low-mass hand wheel is much easier to start and stop and this might be more important to the user than being able to maintain speed.
I'm not sure I understand why a free-motion embroiderer would necessarily 'need' fast initial speed but a low-mass wheel of large diameter would achieve that. (Stitch formation is theoretically the same at any speed, all other settings being equal.) I suspect what she's saying is that at speed, she's concentrating only on the design she's creating, freely moving the material at a constant motion so that she can predict what the stitching will look like and where it will be several seconds prior to reaching that point in the material. Free-motion sewing can be done at any speed.
Another great machine. Love the decals.
ReplyDeleteThanks, Michael. Even industrials had decals back in the day and these are especially beautiful, imho. Now I just have to find an appropriate treadle stand. I've decided that I'm not concerned that it be a Singer or from the same decade; I need the stand to be sturdy (it will be more top-heavy due to the industrial machine), it will have to be retrofitted relatively easily, and strong enough. Nice wood would be a plus but I can refinish something if necessary.
DeleteAnother project.