Constabulary

Please post pictures of your machine. If possible one pic from the left side with removed face plate please.

Did you read the manual? Maybe not correctly threaded. Please post some pictures of your threaded machine and one view from the open slide plate that covers the hook.

You should post some pictures of your machine so we know how it looks in its current state. Do I get you right - you want to convert the 45K56 jump foot machine into a 45K25 roller foot machine? If that is the case you may need an OEM Singer or Adler roller foot that slides onto the presser foot bar and you have to remove the parts the govern the jump foot mechanism (IIRC). I´m ot sure if after market version of this kind of heavy duty roller foot do exist. But you may need some other parts as well. It would help if we could see your machine - please post some good pictures.

I can´t help but just today I read in a Pfaff mechanics instruction manual (for Pfaff 332) that ex factory there is a 10% difference between F and R stitch length in order to not pierce (damage) the thread of the forward stitch. This has nothing to do with your machine but from my observations there very often is a difference between F and R stitches on different machines - maybe for a purpose? Not sure how different the machines are internally but externally the Pfaffs often have the same stitch length lever so maybe this is an idea for you: https://www.youtube.com/watch?v=wtT7QejY2eQ

or compare measures from the offer with your bobbins

I once owned a 110w which is the flat bed Version basically. Cool machine but way too short stitches for what I do. You will find the gears in the parts list of your machine but I honestly doubt there will be gears for 4-5mm stitches. This is an extract from the 110w parts list. Not sure if the gears are the same in your machine so this is just meant as an example. I think the stitch length (stitches per Inch) is the number behind the part numbers.

Just a guess - It may have happened that they sorted screws into the wrong bin. I once ordered screws for the 29K71 paddle spring on the needle bar and received screws for the 29K72 hook spring. You never know - this happens. Since they have the screws and the needle bars too ask if they could check if their screws fit their needle bars cause you think an error could have happened while sorting the screws. The needle bars of the Adler 67 167 69 169 and so forth should all be the same.

You are aware that you have not installed the needle plate in the video, right? Without the needle plate in place it will never work correctly.

The timing is the same as for the Singer 107w or 143w cause they are using the same hook. Difference is that the 307G2 has the hook drive gears covered in a grease filled gear box but thats not relevant for the timing. Hope this helps: Also check this thread - as I said before the hook is the same on 143w and 307G2:

I think Singers UFA / 29 was the earlier model but I don´t know if a license was sold to Adler but I don´t think so.

my records say the 30-15 is a small bobbin machine and 30-17 is large bobbin.

Hope this helps: https://leatherworker.net/forum/topic/96574-singer-51w56-needle-bar-conversion/?do=findComment&comment=659864

Thats ONE story - I also have heard that they stopped making this machine before the war cause it was too complicated (too many parts) and the competitors (Adler 30, Singer 29K...) were cheaper to produce. I don´t know - maybe the truth is somewhere in the middle.

@Pharvey Hard to tell from the distance... See the large slotted screw next to the long handle? Try loosening a little bit, maybe it is too tight. Just a guess. If it does not help post some pictures from the rear and the right side of the head. It is the 1st Class 17 I have been working on but I managed that it is making quite long stitches - longer than 5 SPI actually.

I meant 29K72 But as WIZ said, post a picture of the shuttle to be sure it is a large hook machine. I could be "downgraded" to 30-15 - you never know...

Basically a short Arm version of the Adler 30 - usually the short arm is named 30-15 BUT the 30-17 should have a LARGE shuttle hook but with short needle (no high lift). A rare machine but in case you need parts most parts of the Adler 30-1 and 30-7 should work with your machine. The large hook and bobbins is the same as for the Singer 29K71. The machine seems to be a quite early one cause it has no quick release for the hand wheel which allows to wind the bobbin w/o running the whole sewing mechanism.

@Stevens6 this is a manual for the 29K71 which more or less is the successor of the 29K51 - the two machines are very similar but not identical but it will work for your machine. https://leatherworker.net/forum/applications/core/interface/file/attachment.php?id=135841 Hope this helps

The springs should work!

It is a darning machine - not even a sewing machine. If it is in the state as it once left the factory it does not even have a feed dog (for feeding the material) or a stitch length adjuster so It will not produce a seam with constant stitch length at all but we have not seen your particular machine yet. Maybe someone reworked it in the past.

The above info sheet seems to be from the original 441 manufacturer JUKI The linked Sieck 441 K looks like the Cowboy CB 3200 and not like a CB 4500 Neither SIECK or COWBOY are manufacturer of sewing machines, they just put their own label (brand name) on Chinese made sewing machines and they are free to give them a name of their own choice. The price on the SIECK website is w/o VAT - add 19% for German VAT.

obviously a 227R - maybe from a different batch. Also check SEIKO CW-8 or Consew 227R - basically all the same machines.

Maybe the racks & pinions in the gear box are worn or maybe the hook tip is worn. Are you sure you are using the right needle system 332 LONG (not 332)? Make sure the long grove of the needle is facing left.

some years ago I visited their factory and bought some smaller spares while I was in the area for picking up some machinery (for sewing & wood working IIRC) - very nice folks there indeed!

Maybe worth checking with Global Sewing Machines and see what they have. They are NL based (Haarlem) and also have used 441 machines as it seems: https://globalsew.com/product/juki-tsh-411-normal-new/ Or maybe SIECK in Germany: http://www.sieck.de/en/machines/sewing/saddlery-sail-maker-heavy-duty-materials/arm-type-machines/?produkt=6832 EDIT: Looks like the Global Juki 441 are just drop feed - anyway - maybe worth checking with them.

College Sewing or Trojan Sewing in the UK are quite good sources for parts for certain Chinese / Japanese / Taiwanese made machines. But since BREXIT importing things from the UK became more expensive.