Ok, so if you haven’t run into it yet, EvapoRust is a bit of a miracle worker for anyone that works with ferrous materials. Last time I picked some up it was about $30/gallon? Gentle enough to leave original 60+ year old paint in place, but still breaks the rust down and leaves bare metal. It is very slightly acidic to neutral (pH of 6.1-7,) this is good because shellac such as that on the windings can be wiped out by a base.
So, I broke the starter down as much as possible. (as you can see in this post)
Got as much of the loose rust out as possible, put it in a container and cover it with EvapoRust, I’ve got a cheap aluminum cooking pot that I usually use, but for odd shaped stuff you can use PVC with an end cap, or heat-seal some thick plastic sheeting or whatever works. Once it is covered, leave it soaking overnight at a minimum, 24hrs is usually recommended.
Towards the end of the 24 hours I put the entire container in my ultrasonic cleaner. Its an amazing tool (if you don’t have one, look into buying one, largest one that you can afford/that fits on your bench) and let it run for about an hour.
Afterwards I generally flush the EvapoRust off with hot water and inspect everything to make sure it took care of it all. If it looks good, clean and prep for paint or reassembly or whatever the next step is.
You can then strain the EvapoRust and reuse it a few times before having to dump it out.
.
