Pfaff 4145 (combination of Pfaff 145 and Pfaff 4143)

[Uwe]

Are we even sure this is the correct original Pfaff looper? Do we even know what the correct looper looks like? Many Pfaff parts have part numbers on them. The looper may already have been replaced by one that only sorta-kinda works. The geometry of the looper likely determines how big of a loop it holds and how much thread it pulls off the spool. If the loop size is different from what the thread take-up lever is designed to pull tight, then the stitches may be tight or loose no matter what your thread tension settings are. I suspect it's similar to how the thread take up lever has to match the hook size on lockstitch machines.  

The 102025 looper in the parts diagram looks quite different from the one on your machine.

Edited November 4, 2017 by Uwe

[Brtz]

shame I did not check the part number earlier . Thanks Uwe.

exactly that is no 102 025 looper but 233 094 'ersatz' probably purchased here in Poland

http://www.bullmer.pl/pl/szukaj.html

ok then. I have what I have so far. If anyone has heard about the original 102 025 looper I'd be interested in...

I am also attaching 3 axis perpendicular view of the looper to show how it is curved. Also two general views.

Sad. Bert

 

[Uwe]

That 233 094 looper sure looks like it was designed to pick up the thread on the left side of the needle. It might be worth a try to turn the needle around 180˚ to have the scarf face towards the left, and then adjusting the position of the looper to also pass the needle on the left.  With a little luck, it'll just work.

That's some fancy laser marked number on your part - it may actually be an original Pfaff looper part number 91-233094-05. Not sure which machine it's intended for, though. 

There's also a good chance that your looper is actually the original, correct Pfaff looper. Perhaps the needle just got turned around at some point by accident. 

Your looper is an expensive part, too. It shows up in my vendor database for over $120 wholesale - and that's for the generic, non-Pfaff version. 

Edited November 4, 2017 by Uwe

[Brtz]

I just checked the left side looping and mirroring the needle. I had to lift a needle bar about 2mm cause tip of the needle hit the body of the looper. That is why I cannot agree the looper was designed to work having needle on its right side. The body of the looper has the rounded hole inside the body and the needle is coming into this hole when the looper is fixed as it was previously, having the needle on its left. Second bad effect of this experiment is that the needle starts stabbing the thread. So it means I had less then a little luck this evening :). Anw thank you Uwe for your suggestions. I am learnig a lot with all of you. 

As for the tensions I ordered a new check spring 91-010 023-05. I do not like the spring I have got in my machine. It works like it was from the tank.

Regards, Bert

[Brtz]

Hi,

Stupid question: can single thread chainstich machine sew in a reverse mode?

Bert

[Uwe]

Just flip the big stitch length lever all the up and it should sew in reverse.

[Brtz]

I know how to turn on a reverse mode on Pfaff 145 Uwe. Thank you. The problem is that flipping this lever up does not switching the machine to the reverse mode. It is passing thru "0" stitch lenght and begins to sew in... forward mode again  

[Uwe]

If you knew that why didn't you say that along with with the question? The machine is hard enough to figure out remotely without trick questions.

I don't see why Pfaff would make the large lever purposely operate the way you describe. Maybe parts of the feed mechanism are wrong or totally out of adjustment. Maybe the lever cover plate is incorrect. There are dozens of feed mechanism variations and combinations in the Pfaff 145/545/1245 series alone and there's really no guessing exactly which bits they combined for your machine. My Pfaff 545 with extra long stitch length also does not have reverse, but it also has a special cover plate that restricts movement of the large lever to the top half of the normal range of motion (it also has full FWD at the top position instead of the normal bottom.)

This machine is just fountain cool weirdness. Since there are apparently no manuals for this exact model and nobody else has direct experience or access to that model, it's all up to you now. Try out all lever combinations and report back. Find out part numbers of your feed mechanism and compare them to existing manuals. Don't rely on your initial assessment of it being a combination of a Pfaff 145 and a Pfaff 4143 being correct, either. It may look that way at first glance, but so far the functionality details and key part numbers (e.g. looper) don't really support either.

[Brtz]

Thanks Uwe. And I am sorry. That question was misunderstanding, maybe because of my english. I asked if it is physically possible to make a single thread chainstich in a reverse gear - in general. Not only on pfaff 145. 

In my machine there is also exactly the same lever cover plate (named "scale") as in your machine which restrict the lever movement to the top position half-way around "0" stich lenght. But after removing this plate I noticed that the lever can move up to the very top also not only to its half way as the scale allows to. That's why I supposed that it would be possible that someone install wrong scale and the machine in real can also sew in reverse. I only doubted if it is possible to make a chainstich in the reverse movement in general. Sorry for that.  

[gottaknow]

Single needle chains stitch machines don't backtack in a way that lockstitch machines do. It's a basting stitch designed for pre-assembly of component parts. The stitch is easily unchained and removed by pulling the thread where the stitch ended. The beginning of the stitching will not come out. It is simply for joining materials that are sewn over, or bartacked later in the process. All it has to do is not unchain until the next operation. The easiest way to do this is to "chain off" a little extra which makes it harder to unchain. ALL chainstitch sewing must be secured at the end of the stitch. For a joining stitch, in the case af a single needle chain, you'll never get the tension tight enough to make a secure seam. Anywhere along the seam, if the single thread is cut or abraided, it will unravel.

All chain stitch types are the same way, including two thread machines, cover stitch, overlock, blindstitch, chain stitch button hole machines (there are lockstitch button hole machines), line tackers (Reece S2 class), blanket stitch, basically any machine that doesn't have a bobbin. In a circular operation such a hemming pants with a blind stitch, you simply overlap at least an inch. 

All that said, the single needle chain machine is very useful in a limited scope of applications. In custom sewing for example, you can quickly sew together a dress, do a fitting, and quickly make adjustments then re-sew inside the seam allowance with a lockstitch. The basting stitch is quickly removed after final sewing. As a side note, you can preconstruct something using a lockstitch machine by loosening the bobbin tension until the needle thread is laying on top of the material so it can easily removed. 

Regards, Eric