Grant, I have a horde of old machines like that - I'm working my way through them. It is so cool when they get all cleaned up, adjusted and sold. I usually have two of my grandkids help with the initial clean up. Miss Lovie loves to clean out lint and she is very good at it and Wilbur loves to oil things and he is getting very careful. One day I got out a rusted out old Kenmore and we baptized it in oil. Now I have taught Wilbur to only use a drop of T-F and oiling one like that blew his little mind. Low and behold the machine turns. It still doesn't zig zag but we did a real make over on it. The kids did me proud. The upper zig zag stamped metal on the control part has rust in there I'm going to have to figure out how to get it cleaned up with out causing damage. There is some paint damage to the machine in that area, too. We also took apart the bobbin area and cleaned off all rust and muck. Then I asked him where it went. His little fingers couldn't quite get it in there but he knew exactly how it was suppose to go. We ran out of time to do the tension. It is one of the older 158 Kenmores - I think those are the bomb so looks or not it would sew some guy gear. I haven't test sewn it yet - too much going on for this poor ADHD to handle and I don't mean Wilbur. Oh when we did the Kenmore he looked over the machine and then said "Grandma that isn't a Singer." I asked him what it was and he said it was a K.E.N.M.O.R.E but he didn't put it all together before someone told him it was a Kenmore. I assured him it was a good machine though. He was a little nervous when I told him he could pour oil on the rusted areas. Now I think I should go back and clean up - I guess I figured the oil would wash the rust pretty much and it did. That machine will never be pretty again as far as I know. So we have not had total success on that one yet.
Then I got out an Electro Grande the next time he was over. It was totally stuck. The two of us went over it real nice. He stuck with it for a couple hours. AND it is still stuck. I believe it is the needle bar. Wilbur cleaned up a lot of dirt and saw markings on the bottom so we cleaned some more and found B.R.O.T.H.E.R which he read - he got the biggest kick out of that. So we had a good discussion about how to know who made a sewing machine. I'm sure that bit of info is tucked away in his little head. He loves facts. The Electro Grande is waiting for a shipment of Kroil.
BTW Wilbur had a Bob the Builder obsession for awhile until he figured out that Bob didn't DO anything. He wants to learn to DO things. He is 4 and reads and does his sister's second grade math - he sneaks and uses the computer programs - he's self taught. He stays pretty focused or is it obsessed with what ever he does. I think some people medicate their kids for that but we enjoy him like he is.