For anything you can't remove from the car, a belt file like this.
Or a flap wheel on a grinder if you can get it in there. If you can remove it and the part fits in a bucket, then electrolysis works well and is cheap. I used a broken laptop charger and an old door hinge last time I did it.
Painting the area is important too. Give it several coats of zinc and as many coats of paint as you can. If the area is somewhere not easily visible and away from anything rubber then I always coat it in grease.
I use that exact same finger sander.
I used to use a proper branded one but when that died I gave the Silverline ones a go. They aren’t brilliant, and are a bit under powered, but are excellent value for money compared to a professional model.
For me they tend to last around a year before they die.
I use the silverline one too. Not the reason I chose the picture, it was the first that appeared! Mine's lasted me about 4 or 5 years and I use it quite often. I agree they're underpowered but it's just about powerful enough to get the job done.
One nice thing about them is they seem to use a proper bearing on the end. I have borrowed a more powerful model from another manufacturer, can't remember which one, but it didn't use a bearing, just some strange, crappy bushing type thing that got completely cooked. Shame, as it was noticably more powerful and the motor was still fine, but couldn't be as easily repaired due to that stupid arrangement on the end of it.
I need to clean up my rear beam at some point too. I'll probably use electrolysis, as I have an old dustbin (rustbin) outside that I can do about half at a time. Eventually I'll need to do the subframes. I think I'll be good for the rear but the front is going to take at least a bathtub. I might get them professionally dipped just to keep the insides nicely protected.
Edited by Communist, 25 October 2020 - 08:48 PM.