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I recently listed one for sale on this board. There's a picture of the case with it. http://www.quiltingboard.com/items-sale-trade-f20/1954-singer-99k-$120-t182642.html scroll down to the bottom of the pictures for the case.
You can have any design you want. As long as it's loops!
I, too just bought a Singer 99K from an antique store. It is in good condition except the case around the handle has 2 holes where it should be attached. They had tryed to repair it, but my husband said he could do a better job, but that will be in the future. I've been sewing with her and I love it. She had been cleaned before I bought her but I did oil her again. These vintage machines are so much fun!!
I have a lovely 99K in the bentwood case, its a hand crank; sews beautifully.
I like that glow green seam guide. Might I ask where you got it?
You will probably want to refer to your machine as a “99K” instead of K99. It’s actually a 99K31, made sometime in the 1950s in the Kilbowie Factory (that’s what the “K” stands for) in Clydebank Scotland. The motor may have been made elsewhere. Look for the metal tag on the motor. Many of the later Kilbowie 99K machines here in the USA have motors on them that say made in Canada.
The model 99K31 has a backtack on it (can sew backwards) that was billed at the time as a "red dot indicator stitch length regulator”, the latest model 99 innovation. The numbered tension dial is also a sign of a later model 99. You’ll notice that AZ Jane’s and Purplefiend’s older machines both have no backtack and have a plain tension dial.
Your machine takes common needles found nearly everywhere, either type 15x1 (Singer number) or 705 (Schmetz number). Replacement slide plates (bobbin cover) are available new. It’s part number 32569. Your machine takes Class 66 bobbins commonly available.
Your machine probably came originally in a rectangular-shaped maroon and cream case like AshleyR’s machine that she has for sale.
I bought one this morning at a Junk Shop Clearance Sale, but the case had set in water and is completely ruined. The machine has some rust in the hook area and under the machine, but I think I can get it going again. For $5, I couldn’t pass it up. They make great little hand crank machines.
CD in Oklahoma