Monday, July 12, 2010

Building a media blasting cabinet

"To all the fellas out there with ladies to impress
Its easy to do just follow these steps"
1. Make a box

Media blasting is a great way to remove corrosion, rust and paint from old parts. You can farm this work out to a local company (many that do powder coating will also provide blasting services). Cabinets are available from several suppliers and some provide kits to build your own. So why not go DIY on the project?

I chose a DIY kit from
TP Tools & Equipment. The kit contains many (but far from all) of the components you need. While you can buy the just the instructions and then scrounge, build & purchase everything separately, the kits can save a lot of time. I spent around $600 on the kit including the vacuum. If you build this yourself you basically get the vacuum for free (as long you don't count your time) compared to buying an assembled cabinet. At least that is what I am telling myself. I upgraded to a larger window and a carbide tip for the gun. A foot pedal controller is a nice addition but at $100 it put me over my pretend budget for the project.
Items not included in the kit:

Exterior

1. Two sheets of 3/4 inch plywood - as warp-free and dry as possible.

2. Door latch with adjustable cam - can be purchased from TP or pick up something different from your local hardware store. Latches with adjustable cams are rare so I used latches for windows. They work just fine.

3. Hinge for main door - got lucky and picked up a piano hinge for $2 at an overstock store. These typically run $10 and up at the local hardware store.

4. Hinge for trap door - could have used piano hinge but I went with something stronger.

5. Lumber or angle iron for cabinet legs - used old 2x4" and 2x6" left over from a demolition project. $0

6. Grommet or fittings for the air supply. Instead of running the gun hose through the cabinet I instead installed a brass pipe with quick-connects on the interior and exterior. I did not like the idea of a grommet because I wanted a very good seal and the ability to move the cabinet without its hose hanging out.

7. Pipe for the vacuum exhaust - can be purchased from TP but I found a piece of large diameter shop-vac tubing worked perfectly.

8. Nails, screw nails, wood glue

9. Paint - I painted the interior white for visibility, the outside a blue-grey I found on sale as a return $5 for a gallon at Home Depot.

10. 2 tubes of latex caulk - without caulk in your box the project is not finished. It must be sealed up tight.

11. Wood filler - for filling large gouges, etc. Depends how fussy you want to be about the whole thing.

Interior

1. Support for grate - can be built from wood. I used metal pilasters left over from railing project in the house. Cut to fit and welded together (See black iron grate in the picture)

2. Flood light bulb

3. Grating/mesh - I used an old fireplace screen that I found. $0

4. Retainer/release mechanism for trap door. I used a coat hanger, bolts, nuts and washers already on hand.

Initial Assembly 2. "Cut a hole in a box!"

Assembly continues. Holes cut for window, gloves, side door.

3. "Put your junk in that box!"

Ready to put my MG junk in the box for media blasting.

Don't forget your safety equipment including an NIOSH approved dust mask of at least N95 or P100. Even though you are using a cabinet you will get nasty dust when opening the door.

"And that's the way you do it."

Here is the cover from the rear differential "pumpkin" from my 1973 MGB GT before and after. Now ready for paint.

* lyrics from a song about a box by Justin Timberlake.