WallyP

You DO NOT want to breathe the very, very fine glass dust from the broken beads!!

One possibility:

Pick up a working furnace blower. Put it in a wooden box with a well-sealed door and a standard-sized furnace filter on the input side. Hook a hose from the cabinet to a cat litter bucket, and from there to the suction side of your box. Put a dryer vent hose from the output side thru the garage wall.

Make sure that everything is well sealed, especially around the air filter. You can use a double layer of filters, throwing the outer one away when it clogs, moving the inner to the outer position, and a new inner filter.

Rob Edwards

Wally-

I lack the skills (and time, but mostly skills) to be fabbing my own filter system but you make a good point about the dust- I'll look at a proper dust setup. Every time you open the sidehatch (ha!) all the beads that have collected along the sill fall out on the floor. Not a lot, but still.... A toploading cabinet might be better. The toploader also requires less space to the sides, though the vacuum port still sticks out the side. I got the cabinet I did because of cost, size, and its weight. Even with 25 lbs of beads in it I can pick it up, and move it out into the driveway, so A) the bead mess is easily swept away, and I'm not re-breathing cabinet exhaust as much. They warn you NOT to use this cabinet with silica sand. The last thing I need is silica-induced interstitial lung disease. No thanks!

Another consideration is the light inside the cabinet. On the one hand, the supplied light is weak so pulling the cabinet into the driveway helps with illuminating the cabinet. OTOH, bright outside + dark inside = lots of reflections on the window that obscures the view.

SeanR

Here's the link, don't know how well it works.

http://www.harborfreight.com/cpi/cta...emnumber=94275

dr bob

Most tools are rated at some CFM at some pressure. There's a duty cycle number buried in there someplace too. probably a much lower number than the real-world use you put it to over a short time. Maybe the duty cycle down-time includes sleepy breaks for the operator. Anyway, the common cure is to manage continuos-service expectations with a pressure regulator. Functions more as a flow regulator in this service, but effectively levels out the air use to something the compressor is able to deliver. Try 70 PSI continuous and maybe it will keep up a little better.

Wear ear protection and at least a dust mask. The noise from the blast nozzle, the compressor running and the scream of the vacuum cleaner all will conspire to rob you of some hearing over time. My compressor is in a sound-insulated cabinet now for common stuff, but would get a little warm inside with continuous use. My shop vac has an exhaust muffler that does an amazing job of cutting down on noise.

I used to have a plywood lid for a trashcan that made it a pre-collector/filter for wood chips before the shop vac. Used washable furnace filters and had big piping inside to lower the incoming velocity and direct the stream down inside a bit. I'd be tempted to do that again with bigger hose from the blast box to keep the velocity down, and restrict the incoming air to the vacuum to where it was just enough to maintain a min flow to get the airborn dust into the trash can. Keeps the vacuum from collapsing the trash can. The vacuum motor uses the least amount of power when it's restricted (counter-intuitive telltale: motor speeds up with less load), but may get warm if it's depending on lots of airflow for cooling. I'm sure there's a way to put the top of the shop vac power head and lid onto a box that sits on a trash can; furnace filter in the bottom per Wally, and adjustable vents from outside to manage the flow through the filter by bleeding air in after the filter. Think radial inflow at the top of the trash can to the dust cyclones out against the trash can wall.

A positive feed painters facemask is a lot better than a dust mask. Even a gopher-mask would be a better choice.

Rob Edwards

Followup:

After blasting more or less anything that would fit in the cabinet, I took an entire engine's worth of brightwork to be re-plated (zinc, then a chromate wash, if I understand correctly ) by a shop Greg Brown recommended. $95 later, here's the result:

90 S-4

X-Mas in March ! --- Excellent ! what motor are you putting these piece's on, the one in the car
now or are you doing something with that spare GT mtr you picked up a while back ? Do I smell a
stroker in making ?

RyanPerrella

wow, pretty!

thats a ton of stuff to have done for $95

NICE DEAL!

dr bob

Damn!

I was trying to justify painting the intake and cam covers. Now the whole motor has to come out. All for six hours and $95 worth of plating.

Thanks Rob!

Rob Edwards

Joe:

Yes.

G Man

One thing I would suggest from my past experiences with blast cabinets is to get a few replacement viewing windows. You would be amazed at how fast the glass gets pitted and makes it hard to see your work. We used to go to the local glass shop and have them make us ten at a time. The glass is not tempered so it is pretty cheap to buy. Makes a world of difference when you put in fresh glass.

Larry Velk

The bro-in-law (a tool and die maker) converted his home made bast cabinet to pressure rather than vac. I also saw the method in a car restoration magazine, maybe "Car Restorer".

dr bob

?? Do you just seal off the vent port? Air is coming in with the abrasive media, wants to go someplace. Using the vac or dust collector filter setup is what keeps the media from finding ways to get on the floor. It might be tempting to add a coarse (screen) filter on top, with a finer paper filter around it, and just vent the cabinet to atmosphere that way. Maybe do it at the top of a large-diameter pipe stack so the entrained particles will drop out of the rising airflow, back into the bottom of the cabinet?

Rob Edwards

This is very true. The cabinet came with a 5-pack of plastic sheets that have adhesive around the periphery. About $2 a sheet. I have maybe 6 hours of use on the cabinet now and the first sheet is trashed in the middle- I'm craning my neck around the edges of the window so I can see and then it occurs to me I have spare sheet protectors. Duh. Replacing it made a huge difference. The dust also tends to cling to the protector (there's a huge amount of static electricity generated by blasting, your forearms get zapped constantly while you're working), so you can windex the interior surface of the window regularly- that helps too.

Marine Blue

Very cool Rob, your parts look new again!

I have access to a Media Cabinet at work which I plan on using on some license plate frames. I just need to find a local plate shop to perform the gold plating to bring it to original condition.

MissBehavin'

Rob, great work on all the parts.

I had to laugh at the static electricity thing. I was waiting for someone to say it. We have a larger one and it is addictive. BTW, the static electricity does not zap this girl in the forearm!!

You should definitely be careful not to use media on a rusty piece of hardware and then do something stainless. No filter in the world will prevent tiny bits of steel embedding themselves in the stainless. You won't notice it at first but it can speckle with rust if left in the elements.

Some real thin stuff can distort with heat of you concentrate the nozzle too long in one spot.

Stick the bolts in cardboard so they won't get lost. Watch for carpal tunnel...I have to go find something to blast now