Winter wonder land, or how to media blast in your garage
Media or sand blasting makes a huge mess. Essentially you force a volume of abrasive media (Baking soda, aluminum oxide, glass, walnut shells, etc.) through a gun with high pressure air. This process generates two effects, one any paint, rust or other soft/loose material is blown away leaving clean metal. And two the media plus whatever it removed is also blown around the area.
Media blasting has it’s uses I like it to clean really rusted parts, it’s also good for getting in to tight areas, that would be hard to impossible to sand. It’s also less messy and nasty than using chemical strippers. The main drawback, (If you have not figured it out by now) is that it generates a huge amount of dust and media all over the place.
Many years ago I read an article in car craft about how to build your own paint booth at home. This seemed like a great idea for media blasting. Off to the local big box hardware store for following
- several boxes of painting drop plastic. I bought the heaver grade of the plastic, but either should work.
- Masking tape
- Large house air return filters ~ 4 Square feet, or more
- 20” house fan, cheap one, or old used on you no longer care if it works
- Scrap cardboard
I used the four posts of the auto lift as my uprights. I wrapped plastic around the outside of the lift, then across the top. Using tape I sealed the plastic to itself. You don’t need to worry about making it air tight, the fan will be used to create a vacuum. I then cut a hole on the front large enough to allow the air filters to be taped over the hole and air can pass through. I then did the same thing on the other end by the garage door. I taped the plastic to the outside of the fan. Using the scrap cardboard I built a duct from the fan to outside the garage. I also used some plastic to create a barrier from the partially opened garage door, and the floor to keep dust from blowing back in.
To Test I turned on the fan and was happy that the plastic sucked in, thus showing the fan was creating a vacuum. Now the media blasting can began.
I used a harbor freight 40 lbs soda blaster, and about 150 lbs of extra course baking soda. I do recommend that you get a 5 gal bucket with a piece of window screen taped over the top to act as a filter. I did find a few larger chunks of baking soda and the screen helped to keep from clogging the blaster.
To use the blaster you need a face mask, and a good filter mask, a long set of thick rubber gloves. I also wore a long sleeve shirt and heavy jeans. Like stated above the media is abrasive and will very quickly remove flesh. Also you don’t want the dust in your lungs. Aside from the abrasive media, a lot of older paints contain lead.
Make sure you have a good air compressor, as this process uses a lot of air, and a smaller compressor will only blast for a few minutes and require you wait for it to recover. Using the media blaster is very easy, you point the tip at any paint, crud, or rust, and watch it get blasted away. Since I was using backing soda, it would not blast away large rust chunks. But if you’ve been following along on this blog you know that most of the rust has been taken care of between the plasma cutter and a wire wheel.
Take a look at the pictures below to see how the process went. The only real down side, is every pound of media I blasted I had to vacuum or sweep up, in my case about 150 Lbs of it, as baking soda cannot be reused.