We use three ultrasonic cleaners in the shop. The two smaller ones we bought on eBay. One is small for screws, springs and such. The slightly larger one is for small to medium size machines, carriages and other long stuff. The large cleaner is a commercial item used mostly for Selectrics.

This typewriter was quite grimy, so I removed the shell (fairly challenging) and gave it a bath in an ultrasonic cleaning tank. Mitch Hamm alerted me that such tanks, big enough to dip a portable while keeping its keys out of the water, are now available for a mere $150 or so. Here’s the Royal undergoing what sounds like electroshock therapy, but is really just a micro-agitated bath. Concentrated Simple Green Industrial Cleaner & Degreaser was added to hot water in a 1:20 ratio.

Yep, some times hard to tell from the listings. Look for the inside dimensions of the unit. We have a three gallon (screws and small bits), 13 gallon (carriages and dunking half a typewriter) and a gargantuan gallon for Selectric machines.

We switched to Ultra 3 detergent after using Dawn detergent for years. A quantum leap in effectiveness. When we got the new Ultra 2100 cabinet ultrasonic unit it came with a gallon of detergent. We used it ONE TIME and the parts came out so much cleaner, almost brand new. The detergent is expensive, yet we've never gone back.

We are often asked what ultrasonic cleaners we use in the shop. We have three. The large cabinet model that holds large typewriters such as Selectrics, a medium sized 12"X20", and a smaller cleaner 10"X12". The medium and smaller ones you can buy on eBay all day. The models change, and the sizes are all similar. The medium sized cleaner is used for small to medium sized typewriters and the small machine is mostly for nuts, screws and other tiny stuff.