I have recently been given a 1948 Singer 15-90 Sewing Machine (original post here) and being the information hog that I am have been researching the 15-90’s for hours on end. It is pretty fascinating stuff, but I have had problems finding info on the 15-90 specifically. Apparently they’re identical to the earlier 15-89’s but electric and identical to the latter model 15-91 but with a different motor. What I really need is the original instruction manual, which would give concrete particulars on things like the motor not to mention threading and notions. Singer’s website has a free manual download for almost every machine they made, unfortunately they don’t have mine. Everywhere else I’ve looked lists the 15-90 under the 15-89 manual, main problem of course is the 15-89 wasn’t electric. Oh well I suppose I will eventually break down and buy one-off eBay.
As far as getting it running goes, I’ve dismantled the shuttle completely and cleaned all the rust off the components.
I also discovered that the bobbin that was inside the machine is the wrong kind (it’s a 66 but the machine needs a 15). So far it looks like the motor is the only thing wrong. The wheel turns fine, and moves the needle up and down without hitting the bobbin case. I think the mechanical parts will just need to be cleaned and oiled. The motor is another story, I will be taking it apart next. If it turns out to be un-fixable I might convert the machine to a hand-crank instead of messing with a replacement motor.
For anyone else looking for info on the 15-90’s I recommend the 15-89 or 15-91 manual which has the same threading as the 15-90 and can be downloaded free off Singerco.com. I also recommend the Vintage Singer Group Handbook which has great general info on cleaning, restoring etc. you can get it by joining the yahoo group Vintage Singers. It’s a total pain to join their group, but apparently that’s vintage sewing machine forum protocol, I am in the middle of jumping through hoops to join Needlebar.org. I understand wanting to maintain a solid community but come on do you really need to force members to write an introductory post before they are allowed to even read other threads? Do ya?
UPDATE: I have finished restoring my Singer here are the links to the other posts:
Part 2: Assessment, light bulb tutorial, and electrical diagram
Part 3: Disassembly of machine, cleaning, reassembly
Part 4: Tensioner reassembly
Part 5: Fixing the electrical components
Part 6: Last adjustments and replacements