Specs And Instructions For The Singer 251-21

[SARK9]

New guy to the forum here.

I'm having a bit of a time finding much info about this particular machine...I am wanting to set this up as a dedicated binder for edging a couple of layers of 1000D Cordura, but I'm finding conflicting info as to even which needle system is correct for this variant. I did find a parts list specific to this machine, but no general operating manual with the specs. I was pretty much given the machine and stand with not so much as a spare bobbin, let alone the paperwork.

Has anyone here used of of these and/or maybe seen a copy of the manual?

Thanks!

-DonC.

[Cobra Steve]

Hi Don. This is a garment machine from the 40's and 50's. There are millions of them still around. It uses a 16X257 needle. It will work for what you want, but not as well as a walking foot or compound feed machine. Steve

[CowboyBob]

Here's a copy of the 251-22 which is very similar: http://parts.singerco.com/IPinstManuals/251-22.pdf

[SARK9]

Steve and Bob -Thank you both for your replies, and my appologies for taking this long to respond. Part of the conflicting info I've been a bit stumped by is this excerpt from the 251-21 PARTS manual- And some very different information from other sites such as ISMACS.

[SARK9]

Some random info I've gathered about this fabric-type machine as we move along.

The 251-21, like the 281-21, is the short arm version of these commonplace machines, with an 8 inch clearance to the column and a table cutout of 15-1/4". My example does indeed use the 16X257 needle rather than the 88X9 listed by the ISMACS chart, but I was interested to learn that this *same* needle in sizes larger than #18 is designated the "16X95". I bought some #19 & #20 16X95 Schmetz needles to verify this. The max foot lift IS 9/32" rather than 3/8ths, and the max stitch length is 7 per inch. Several similar machines have 5-1/2 stitches per inch listed as an option so I'll be keeping an eye out for some likely relics to canibalize & see if there is some easy parts swapping to be done. My impression of this model is that is is a pretty rigid, sturdy, basic straight stitcher with some pretty significant dimensional limitations, but otherwise not too different from the 31-15 for use as a utility mule. Mine will hopefully be finding happiness as a dedicated tape binder for 2-6 layers of coated 1000D Cordura, and some quick trials have shown it is totally happy stitching/tensioning T-90 thread. If I had a single main complaint about this series of machine it would have to be that the bobbin size is absolutely miniscule for using anything heftier than T-45 thread.

My stand came with a small clutch motor that someone had to adapt to the table, as it does not use the standard 3-hole bolt pattern, and I was surprised to discover I could actually CONTROL the clutch engagement and stitch as slow or as fast as I liked. Too bad the iron outboard races for the pulley unit are worn to a rattle fit that is beyond the ability of grease to amend.

More discoveries as they occur!

-DC

[J Hayes]

Can you bore those races out and press in new bushings?

[SARK9]

I will definitely try to sleeve the worn frames, though the casting is rather "elegant" and there's not a whole lot of wall thickness there to work with if the bushing itself is to have any thickness. I suspect the shaft is in poor shape as well, but haven't knocked it down to look. In terms of function and quality, I think its worth repairing, but the way its all mounted on this table is sort of not up to standard,... with a cobbled-on 2X6 sticking out the back of the table 4 or 5 inches to catch the outside bolts of its square mount.

For now, I'll go back in the original *normal* motor mounting bolt holes and install a spare Consew CS1000 I have.

-DC

Edited December 9, 2013 by SARK9

[J Hayes]

I didn't see the cobble job. Spare motor, seems like you have it solved already with no need to put time into the old one.

[SARK9]

Finished up the conversion to the CS-1000, and installed a torque multiplier while I had it all torn up. I didn't have a spare 50mm pulley with a 15mm bore to use on the servo, so I had to use the 90mm they come stock with. The 90mm pulley limits how close to your servo you can set the multiplier when using the standard motor mounting bolts. This sometimes causes your belt to rub on the near side end of the table's belt cutout. This one just barely cleared. The large pulley I made for this one is a 7.875" diameter; It would not have had the clearance for anything larger than an 8".

-DC

[Gregg From Keystone Sewing]

Correct needle, from the factory, for a Singer 251-21, is system 88X1, also known as needle systems 1128, 88X9, DAX1. I confirmed this from two sources.

This is NOT to say that using a 16X257 needle is wrong, but it may not be setup for that needle. Or maybe it is, at this point.

[SARK9]

The 88x9 was listed in several older sources that I felt were reliable. However, since I saw several others that indicated the 16x257, and I had no real experience with either, I ordered 10 of *both* types and tried them out. For whatever reason, this particular machine would not form a stitch with the shorter #19 88x9's, but happily stitched away with the 16x257's.

-DC

[Wizcrafts]

The 88x9 was listed in several older sources that I felt were reliable. However, since I saw several others that indicated the 16x257, and I had no real experience with either, I ordered 10 of *both* types and tried them out. For whatever reason, this particular machine would not form a stitch with the shorter #19 88x9's, but happily stitched away with the 16x257's.

-DC

A previous owner had the needle bar raised to use series 16x257 needles. It's that simple.