dikman

Now that sounds like a better deal!

I agree with your reasoning. Given the relatively high asking price for the used machines (and if they are too high then they won't sell) and the new cost (which, in the US, is quite reasonable) then I reckon a new Cowboy or equivalent is the way to go.

Looks like the equivalent to a Pfaff 335. Very useful machine, but not for holsters. I'm not up with US pricing on used machines, but I agree it seems pretty high. I'm guessing that it's been re-painted as there are no obvious Singer markings on it. Another thought, if they don't know the model number how can they do a proper service on it? Bit hard when you don't have a service manual for it.

I think Uwe modded a servo control setup to use a remote pedal, basically a mechanical mod. As TT said it would be a major job to try and get one of those domestic foot controls working with a servo. Like most things, anything is possible IF you throw enough money at it, but personally I wouldn't even consider it. Plus you'd certainly void any warranty by trying it. If you're good at DIY then it shouldn't be hard to make a suitable mechanical pedal control, however if DIY is not your thing then I'm afraid you're stuck with the normal pedal setup.

Zapee, thanks for asking this question. While I haven't had any problems with this happening (yet?) I hadn't realised how crucial the two thread guides are. I learned a lot from the answers in this post!

Yeah, most sewing machine pulleys tend to be 15mm. I had to sleeve one for a reducer I made so it shouldn't be too much of a problem. I drilled and tapped the pulley to take a couple of set screws 'cos I couldn't use the keyway to lock it in place.

I stand corrected then, Hockeymender. Mine goes into meltdown if I use a speed reducer . I have read of others having the same problem, but if yours works then it must depend on the servo brand?

My first servo came with a needle positioner, mainly 'cos it seemed like a good idea at the time! I set it up, tried it and didn't really like it. In fact, I found with a servo set up to sew slowly I don't need the positioner. Also, be aware that a needle positioner won't work if a speed reducer is fitted.

The smallest pulleys I've seen are 45 mm (that's what I use). I'd fit the smallest pulley I could to the motor, regardless of whether or not a reducer is fitted.

You made the same mistake I did at first reading - it's 200 spm, not rpm, which equals about 3 rpm. Quoting spm, however, is meaningless as it all depends on the size of the pulley fitted to the motor and the size of the handwheel pulley. If it's a misprint, and is supposed to be rpm, then it's not a very good motor as a digitally controlled servo should be able to get much lower than 200 rpm. Really need the manual to work out what they really mean.

Exactly which model servo are you looking at? My servos can be set to much slower than 200 rpm.

Tut tut, I saw a couple of paint runs! Seriously, a great job there, I reckon you can feel proud to have resurrected it.

Any of them could work, I guess, but some would require considerable modification/fabrication to do the job. Forget 24v motors as sourcing a suitable power supply would be an issue. At the end of the day a servo that's designed for the job and simply bolts in place is hard to beat.

TT, you'd probably blow every breaker in the neighbourhood when that monster was turned on! Gigi, that sounds simple enough.

Could be a bit tricky to implement, Sticks, but worth trying as basically all it will cost you is time. If it works then fine, if not you (we) will have learned a bit more.

TT has a good point about proffering information that could cause problems for someone who doesn't really understand the subject. If you already have a 3-phase motor on your sewing machine then a suitable VFD (particularly if the price is right) could be a viable solution to speed control. However, as Gigi has pointed out, there are problems making speed adjustments on-the-fly unless you have three hands! It will need work to enable speed control via a foot pedal. If you have a conventional (single-phase) clutch motor then a servo is the only way to go. Fitting a VFD/3-phase setup will be costlier and require additional work, whereas swapping to a servo is a straightforward changeover process. Gigi also mentioned changing her clutch motor to a "normal" motor, but again unless you can pick up a suitable 3-phase motor cheap (unless you have one lying around) then it would be much simpler to just fit a servo.

The 4500 S. E. - "True American style" they say........ I'm a little surprised that the 341 can handle 1/2" of leather but only up to #138 thread, otherwise seems like a nice enough machine.

I will have to disagree with you on this one, Sticks. My first machine had a clutch (of course) which scared the daylights out of me the first time I used it!! I made a larger handwheel pulley and made a speed reducer (modified a couple of times) in an attempt to control this beast, all to no avail. Yes, they slowed it down some, but I still had issues, and without fitting a gearbox(!) had reached the limit of a mechanical solution. After reading about servos here (and finally figuring out what they were talking about) I bought one from Aliexpress, Chinese company, of course but with a warehouse here in Australia. Cost was $250 Aus, about $220 US. Best thing I bought, in fact I bought two more! No problems so far, and the control it gives me is awesome. There is no way I would spend $1000 on a servo, not for my needs (and I'm pretty sure many will agree, it's a bit over-the-top for a hobbyist).

Yeah, I can see where that can be a problem (I'm sort of rural but close to the city, so almost the best of both worlds - almost). I forgot to comment on Mr. Gibson's excellent blog, much truth in there.

I'm with you, Big Sioux. I love music and when I'm casting boolits I'll play some nice easygoing instrumental/orchestral stuff but when I'm working with the leather - nothing. It's too distracting because I listen to the music, rather than concentrating on what I'm doing (and as you know, one mistake can ruin a project!).

Pfaff are nice machines, but be aware parts can be expensive.

I do lots of that too . I think you'll find your setup is perfectly adequate without a speed control.

" Apparently servos are all pretty much generic in their design." While this is generally a true statement, design does change, for example the optical operation you refer to appears to be an "older" design and they are using a different design now where the optical gradient isn't used. None of my three units has it, and it seems that once one changes the design the other makers follow suit. The best thing with a servo is to experiment with the start speed and top speed settings and in my case they appear to be interactive to some extent. Also, if you want to maximize the torque at low speed then fitting a speed reducer as well is highly recommended.

Just got back to this post. Your setup looks good, similar to what I use. I'll bet you're really enjoying burnishing now!! As for the servo motor you mentioned, there's lots written about these in the Sewing Machine section. They are generally used to replace the large, heavy (and fast!) clutch motors on industrial sewing machines. I have 3 spare clutch motors that I'm trying to think of a use for! Would be great for a burnisher (bit of overkill, though) if I had somewhere to set one up. If I can sell one of my bikes then I may have room in my garage to make a decent burnishing stand. Something TT said has got me thinking, i.e.mounting the motor vertically with a table around the shaft to act as a guide. Might also be possible to mount a sanding drum in place of the burnisher to give nice square edges.

I guess it all depends whether variable speed is required.