Blasting cabinet question

[MatBirch]

Looking to build a qwik-n-dirty cabinet to get a few bike parts cleaned up.
Is a blasting cabinet airtight? Seems logical that it would have to be, yet it's pumping air in from the outside. What keeps it from over pressuring? Is there usually a filtered exhaust of some kind?

Thanks

 

[Antique Engine]

Cabinets have two vents. One is open to free air (with a baffle to keep media from spraying out) and the other is hooked to a vacuum negative pressure source. This way, fresh air comes in through the baffled hole and out through the vacuum. This pulls dusts out with it, to be captured in the vacuum. If you don't have a good air flow through the cabinet, the visibility will be very poor.

If you're bucks down, a shop vac makes an acceptable vacuum for moderate usage. Over that, the sky is the limit on how big and expensive of a vacuum you can buy.

 

[Hpozzuoli]

For what you will pay in materials just grab a harbor freight cabinet. They have the bench top one and a stand up one. You want it air tight, need sealed gloves to go in to work with, a light, some sort of venting from a vacuum or at the least holes for fresh air and a vent. Sourcing all this stuff then putting it together takes times. Not to mention the sheet of lexan or whatever for a window.

http://t.harborfreight.com/garage-shop/blast-cabinets.html

Mine is the harbor freight upright one. I put wheels on it so I can wheel it around. I shoot aluminum oxide, glass, nuts, and a sand mix thru it. I use it a ton and it has been perfect. It is large enough to get heads in, small engine blocks, and most anything you could think of.

Just make sure you have an adequate compressor. These things need volume and your compressor needs to keep up.

 

[thebeekeeper1]

I too have the largest HF one. You cannot beat it for <$200. I modified it by running a hose from a bottle blaster through the intake vent, as my compressor doesn't have the CFM to run the siphon gun that comes with it.

Few things in life (that don't jiggle when walking) are more beautiful and satisfying than seeing a part go from nasty, ugly, and rusty to that lovely frosty silver color. ::sigh::

 

[MatBirch]

Thanks gang, I can get nearly all my parts for free, or nearly free thru work, so still want to build. I'm gonna brake out the top from 1/8" alum, and cut my holes in it. It will need to live outside, so it will be one piece to keep the top leak free. I have a set of nice explosion proof lights with cages and globes to go inside. I'll probably do the ends and floor from plywood for the time being. I'll design it in such a way that when I can, I can brake out a bottom with a nice funnel shape and replace the floor.

 

[Thumper68]

Here is the one I built last fall with mostly free/ already had stuff.

http://www.garagejournal.com/forum/showthread.php?t=218407