Cleaning With Abrasives
by Pat Goss
Whether you’re bringing something back from the brink or just performing a general repair, you’ll probably find that some form of abrasive cleaning could be very beneficial. But the first thing to remember, you never put anything that’s greasy or oily into any kind of abrasive cleaning machine because the oil and grease will foul the media material that’s used for cleaning and then you’ll have to throw it away. So before you put it into a blast cabinet or anything like that, you clean the grease and oil away using the appropriate type of cleaner.
Also make sure that the media material, the actual abrasive that you use, is the appropriate one for the type of metal that you’re cleaning. And along with that you may have gasket surfaces such as we see here. Those have to be protected. You do that with a couple of layers of masking tape, trim it with an Exacto knife or a razor blade, and that will protect it. If you don’t, you may wind up with a situation where you have gaskets that, they fit, but they won’t hold. They leak.
Now just about everybody sooner or later will revert to one of these or they’ll start out there. This is a bench grinder. It has a wire wheel over there. It seems like it would be the ideal thing for cleaning small parts, but it isn’t. I guarantee you, you take a bolt or some other small part, you clamp it into locking pliers, and turn on the machine and start grinding away at it. Well, yeah, it will look clean, but you take any plating that’s on that bolt, you take it off. You round off threads so it may not torque down properly. And one thing I will absolutely guarantee you, based on experience, no matter how tightly you get it clamped into those locking pliers, it will work loose. When it does, it will go flying. It will hit you, and it will hurt. Definitely not the way to go.
This is from Eastwood, and this is a vibrating tumbler. It has a media material in here. And if you look at this bolt that we’ve cleaned, you can see it looks almost like it’s chrome plated, and it hasn’t damaged any plating or any threads or anything like that. Now it takes longer, but it does a superb job. For this particular operation, we used corncob.
There are more coarse media materials, like the two (on the right) that we see here. Those are for removing rust. And then the final operation is the corncob (left) which polishes the part. It works extremely well. And make sure any time you’re working around anything that is mechanical always wear eye protection, wear gloves where necessary to protect your hands, and if there’s any dust that’s created by any of these things, wear a dust mask. Media cleaning is a great way to go with this blast material and so on.
* Vibratory parts tumbler, uses various abrasive media to remove rust or polish small parts.
The Eastwood Company
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