Blasting cabinet mods.

[th62]

Blast cabinet mods – vapour blaster.

I have one of those small blasting cabinets, however it leaks like a sieve. The top door, through which you load stuff to be blasted is just a sheet of 3 mm acrylic, topped by a flimsy sheet metal surround, consequently it tends to bend and allows blasting media to exit. I tried sticking some rubber around the periphery of the lid but all that did was allow the lid to bend more.

To fix I made a frame to bolt underneath the acrylic made of 20x 10 flat bar, then drilled and tapped 16 x 4mm holes to line up with the existing fasteners that fix the sheet metal surround and perspex together. So now the Perspex is sandwiched between the 20x10mm frame and the sheet metal surround and held together by 16 M4 screws. To complete the job I place four M6 washers under each clamp handle and made raising blocks for under the hinges.

While I was at it I did some experimenting with the blasting gun. I found the original air nozzle inside the gun was too far short of the back of the blasting nozzle, so I turned up a slightly longer one, then turned up a steel nozzle with a 5mm aperture. The aperture was then countersunk at the back of the nozzle.

I’ve found for best pickup of blasting media the air nozzle has to extend past the back of the media nozzle, the countersinking leaving enough room for the media to pass through. That allows the maximum amount of media to exit the nozzle. I did have a blasting gun that came with the cabinet but that was so flimsy it broke when screwing the hose connector into the handle. The gun I modified is a much sturdier type.

In future, I’ll be attaching gloves to the cabinet and converting it to a vapour blaster, this gun should work with a water bead mixture.
I would have liked the next size up cabinet as it has a door that actually seals but I simply don’t have room in my shop for a bigger cabinet.

Next job is to find a way of mixing the water and media, I don’t really want to use a pump, but that may be the easiest way.