dikman

Jersey, you may have just saved yourself from a possibly expensive mistake. On our (local) selling site, there are many industrial machines for sale, some at a good price. Many say that they can sew leather, and they're probably right - to a point. It's only when you start reading, and asking people who have the experience, that you realise that the sort of leather they can sew is invariably not what most of us want to use i.e they are designed for thin garment leather. 99% of what I've looked at have been high speed straight stitchers, and until recently I wouldn't have known the difference! So give it plenty of thought and accept the fact that it will probably cost you more than you originally intended to spend - but it will be worth it.

As Uwe suggested, have you disabled the needle positioner to see what happens? It certainly sounds like the needle positioning circuitry is getting itself in a knot, and it's caused by the addition of the speed reducer. If the circuitry gets a signal feed from the motor and the needle positioner then perhaps it can't cope with the additional rotations of the handwheel relative to the motor when the power is cut?

Jersey, permit me to offer my (admittedly limited) experiences with industrial leather sewing machines. I was given a Singer post machine (a straight stitcher), which I had high hopes for, but through much experimenting and lots of reading of the great advice on this forum, I eventually realised that for sewing leather a walking foot machine (preferably a compound feed) is the only thing worth considering. You will be struggling with anything else. That first Singer is a great machine, for what it's designed for, and I'm sure it will be very useful, but I broke quite a few needles before I figured out that it doesn't like thick/stiff leather! So I just kept looking for a suitable used machine, and whenever I saw one I looked up the model details on the 'net to find out what it was, and it's amazing how each time there were links to this forum! Shows what a great resource it is. I'm slowly learning which models are which, and which ones are worth having.

mmike, if you intend using them for sewing leather then a servo motor is really the only way to go. I have experimented with pulley speed reducers (with clutch motors) on two Singers and a Pfaff 335 and while I could slow them down considerably I just didn't feel that I had the slow speed control I was looking for. A servo gave me that control. Coluber42, I recently bought a used Pfaff 335 that was fitted out as an edge binder. It's a really nice machine and punches through 1/4" leather with no trouble, but it's cost me just over Au$100 to get the feet and feed dog to convert it to "normal" stitching - and these were generic parts, I've been told not to even consider Pfaff parts ($$$)! As long as I don't break anything it'll be a great machine. If you want to do both binding and straight sewing you'll be forever swapping the bits back and forth. It's probably not what you want to hear, but eventually you will need a machine set up for each function if you intend to do a fair bit of work.

Always good to have someone else look at it. I know that sometimes it's possible to miss something because one is trying too hard!! As for the motor, I thought servo motors stopped as soon as they were switched off (mine does) unlike clutch motors, which will keep spinning a long time due to their flywheel.

If it all worked before, i.e. the only difference is the new table, then the logical thing is to put everything back as it was, on the old table, and see what happens. If you still have problems then it's obvious that you've changed something else in the process. If it works fine on the old table then obviously your new table has a curse on it. I'm also at a loss to understand how it keeps running, if the motor has stopped.

"Shoplifters"?

Might have to try using bits of towel myself, as I've found that the first touch of the foam usually drops a bit too much liquid. Have you used Moccasin Brown? I was wondering how that would go, as it didn't look too bad the one time I tried it.

Wax would definitely be the way to go. If you search the 'net you'll find lots of info on making/blending waxes, depending on what you want to achieve. (And some of them smell good too). Lanolin is a good additive for rust prevention, and is not only natural but good for your skin. A beeswax and lanolin mixture would be a good starting point, and a bit of olive oil could be added too (many claim you should only use extra virgin oil). Mutton tallow is another very good additive, and isn't hard to make if you can't buy it. The beauty of the stuff that I've mentioned is that they're all natural and don't go rancid! Johnson's Paste Wax is one that is used for all sorts of things besides floors - used in various boolit lube concoctions, for one - and is highly regarded, in general, by reloaders. (Unfortunately, it's not obtainable here in Oz, although many have looked for it). Blending waxes is a fascinating subject in itself.

Tannin, I read the same thing about using a lump of lead - one of these days I'll get around to making one. I bought an A4 green cutting board from a discount shop, but felt it was a bit small so bought another one and glued them side-by-side onto a flat board. They're not true "self-healing", being so cheap, but should be adequate for my needs. I also have a hardwood log for punching on. I tried one of those poly kitchen cutting boards, but find that the log is better as it has more mass. (I ran a belt sander over the end first, to give me a flat, smooth surface). I also have a piece of glass, should I need a flat surface for using wet and dry paper. The glass is from one of those modern-style scales that you stand on, so is pretty tough! The scales died, so I stripped off all the bits to give me a nice smooth, rounded piece of tough glass (I don't like throwing things out unless they absolutely can't be re-cycled somehow).

It would probably remove the marks, but I suspect it could have some "interesting" effects on the dye.

While what you are doing is of no practical use to me, since I'm only using the servo on a sewing machine and it's perfectly adequate for that use, it had already occurred to me that these motors could have other uses - like on a lathe. In that case some form of speed control, other than the lever system they come with, would be needed - basically a simple rheostat should suffice. So yep, I for one am interested to see what you come up with. Ron, you make a valid point. I just figured that, as a matter of cost expediency, if a factory is producing these control boards then the logical thing is for the "manufacturer" of the servos to source the boards already built rather than go to the expense of building their own. The fact that the controls/display all appear to be functionally similar lends some weight to such a thought. However, I can't say for certain that is the case.

Uwe, thanks for those part numbers, I managed to source the two feet locally (generic,about Aus$28 each, but the guy said I wouldn't want to know the Pfaff price!) but they couldn't help with the feed dog/needle plate. As you suggested, I contacted Kwok Hing directly and they said they would send me an invoice (shipping is dearer than the parts!). I have a feeling that with these parts, and once I get the speed under control, this is going to be a very nice machine to use.

I thik I'll stick to my plain steel needles.......

The listed needle size for my 51W59 appears to be made of the same stuff. I went to a shop that specialises in industrial machines, told them what I wanted and they came up with an equivalent size that they sold.

JB52, I forgot to mention that if you do any mods please post them here. Although I'm happy enough with mine, I'm an inveterate tinkerer and if you come up with something useful.......

Trace, I had issues with the hook sometimes catching individual strands in the thread (Singer 51W59). I found that when I had adjusted the hook timing I wasn't accurate enough and the needle bar was too high. Once I lowered the needle bar (a little more than the figure in the manual - we're talking a mm or so here) it was fine. I'm not saying that this is your problem, but it demonstrates how critical the timing is. You need to get the manual and read it lots of times to understand the timing setup.

JB52, have a look here....http://www.aliexpress.com/sewing-machine-servo-motor_reviews.html Some of these look awfully similar to the Consew CSM-1000. I bought the 7th. one down, and after tweaking the parameters in the controller I don't have any issues with slow speed control. The "style" of the controller appears to vary with different models/manufacturers, but I would guess that the innards are the same. edit: I just did a bit more looking, and this one looks almost identical to the Consew - http://www.aliexpress.com/item/500W-AC-110V-240V-brushless-Servo-motor-with-internal-needle-positioner-for-all-kinds-of-industry/1548752350.html

You are indeed a whiz! Thanks for that. A fur machine......I think I should buy it just so that I can say "I have a fur machine".

Must be rarer than I thought. For those who don't know, it's been described as a bag stitcher, or a single needle/single thread overlocker-type stitch (!). It has a horizontal needle, no bobbin, and an oscillating arm that sticks out over the needle and has a hook on the end to grab the thread. The product being sewn is held, and fed, between two large horizontal wheels that rotate. The guy said I could have it for $100 (hook needs repairing), which includes the table and clutch motor, but I can't for the life of me figure out what I could use it for.

I decided that the smallish pulley (3") on the handwheel really had to go! So after a bit of messing around on the lathe with one of the alloy pulleys that seem to be commonly available for sewing machines (in this case a 4 1/4") I managed to get a bigger working pulley to fit on the handwheel. This made quite a difference, although still not up to the control of a servo, of course. This gives me a ratio of 2.5:1, (the original must have been close to 1:1) and I reckon that if I couple this to a servo I should have excellent slow speed control.

My last servo cost $250 ($205 without the needle sync) and that was pretty much the best value that I could find (out of China). My pulley reducer cost $0, because I used what I already had. I suspect that I'll end up buying another servo, however, as experience has shown me that even with a pulley reducer clutch motors can be a pain.

Can anyone enlighten me about this wee beastie? Google doesn't turn up anything (except the one for sale on Gumtree). Does it have any use in leatherwork?

I tried it out today, with a small (45mm) pulley on the motor, but it's still too difficult to control for my needs. I'll either have to make a pulley reduction thingy, or buy another servo motor. Part of the problem, I think, is the pulley on the handwheel is too small but it won't be easy to fit a bigger one.

Thanks for that list, jimi, it's been added to the growing collection of paperwork for this machine. I can't measure the needle bar yet, as both of my digital calipers have a flat battery!!! The part numbers on mine are - feed dog 46497B (no Pfaff marking), inner foot Pfaff 5.0B, 4C629 and outer foot Pfaff 8.0 A/B, 40432. I've attached a photo of the feed dog, and looking at it under strong magnification it may have been ground down, although why they would go so far down if they only wanted to remove the teeth I don't know. The part no. on the feed dog may mean it's a non-genuine part? The other part no's, while Pfaff, don't appear to line up with their current numbering system. I'm thinking that I might drop into the sewing machine place in town sometime, as he mentioned sourcing generic feet, and see what he can come up with (looks like I'll need the inner/outer feet, feed dog and needle plate). I'll make up a new cover plate for the arm, as the two threaded pins on the existing one have been brazed on, so I'll leave that intact.