I file both sides.

Imagine a rectangle (say 4" side to side, 1" top to bottom) with it sliding into the machine with the left end first and then sliding to the left to close. I would file it so that the right side is a hair (or less) wider. That way as it is just about to "seat" it gets tighter.

FYI - A much easier method for tightening a factory made but now loose slide was shown to me by Cathy. She simply gives the plate a slight bend across the short direction and Viola! it is tight again.

Grant51clone,
I have a 99K with the same decals as your machine has, however my machine is from about 1932. It was electric when I got it, also has the spoke wheel. I did a motorectomy and put my Singer hand crank on it. Its a joy to sew with, the grandkids like sewing with it too.(This picture shows it with the Chinese repro hand crank, can't find the other picture)
Sharon

Pretty machine, Sharon.

grant15clone, your 99 is absolutely beautiful!

Is your Pfaff treadle cabinet still available? If so how much are you asking?

I think we have a Spammer in our midst. On at least one other page that I know of as well. Something about a sewing kit.

Holy Sphinx! I'm in love and now I have to search for one of these beauties. I've never seen anything so gorgeous!!

Diamond knife sharpeners are available from woodworking splys. If it gets too loose you can also centerpunch close to the edge. If no belt sander available, glue sandpaper to flat surface, use a squared piece of wood as a guide so you don't wobble. When you're close, use a piece of stock cut at the bevel angle as your guide to rub against.

My mom gave me this machine this week. Its in sad shape. I've gotten some information from quilting blogs. And I did find out that it was made in 1897. But other than that I know NOTHING. I don't even know how to thread it, or make it sew. It needs a new belt and lots of TLC. Would love to know what you all might suggest. I'm afraid to do anything for fear of making it worse. Cleaning the machine and the decals is my biggest concern.

It's not sad. Unhappy, maybe, but that can change. I would be careful around the decals. Especially around the edge of the silvered parts. I would recommend just sewing machine oil on a soft cloth and work in small areas at a time. The cabinet looks sound for something that is over 100 years old. You can try refinishing it. It looks like a good woodworker could make it beautiful again. You have to be careful because it has a very thin veneer on it. It isn't all that bad of shape, machine or cabinet. But that is my opinion.
~G~