Fantasy blasting set-up? - Ideal world.

[astro_al]

Hi guys, I need to sort out my blasting set-up. So far I have the usual 20 gal blaster and compressed air (soon to be mid-twenties cfm, and very dry).

I have a space about 5m x 5m in which to put my blasting and paint spraying (obviously separate).

I've been umming and erring about whether to have it open, or a walk-in and shut the door 'cell' type scenario, or a cabinet type jobber - albeit a large one.

So, whats the best set-up for blasting everything from little brackets and whatnot up to car sized things? Should I have a little cabinet plus a large area?

I thought about a large steel grating with a stainless sloping-sided trough beneath to catch all the media and collect it. Perhaps just sweeping up from the floor is more versatile for blasting bigger items?

What would you do? Cheers, Al.

 

[rtbcomp]

A walk-in blast room and make it airtight with a controlled air inlet and exhaust. Suck the air out and filter. Draw air in from the outside and installl the extractor outside.

Ideally install double doors with an airlock also evacuated to the outside. Use this space for dusting yourself down. Also install a grid on the floor to stop media being trampled out.

Use a proper air-fed helmet. Beats a bucket with eyeholes cut in it.

Attach a spotlight to the end of your nozzle.

Believe me the fine dust is like smoke, it gets everywhere and if you're painting in the same building you're asking for trouble.

I do all my blasting in a room and use a cabinet and seperate pot for bead blasting. Install the cabinet outside the blastroom otherwise you'll have to clean it down each time you want to use it. Also the top surface of the glass will get scratched.

Illuminate the room properly, I'm looking at 4 or 5 100 watt daylight bulbs for a 6 ft x 8ft room. Make sure the light is behind you in the ceiling. Under poor light it's difficult to tell the difference between blasted metal and some colours of paint, especially grey primer.

Make sure the blast room has a smooth floor to make it easy to shovel up spent media, a cheap window squeegee on a 4 ft pole is ideal for sweeping up, about £4.00 from Towsure.

Commercial blastrooms have a mesh floor and a media recovery system. If I had the clearance under my floor I would install a bucket sized pit and sweep into buckets rather than shovel it up, but the latter isn't too much trouble. Use a plastic dustpan and get down on your hands & knees.

Using a vacuum cleaner isn't great, the heavier media settles in the hose and the dust clogs the filter. The switches on Dyson vacuums clog up and jam after two or three goes!

I run my breathing air fan and a couple of lights off a float charged battery - if you get a power cut you'll be completely disorientated. One light is above the door, the other above the air valve. I may fit a solenoid valve to cut the air supply.

Another problem I had was that I couldn't hear the doorbell when blasting, which meant I couldn't work if I was expecting a caller - I rigged up a repeating car horn and flashing lights triggered by the doorbell - I can let you have the circuit if you like.

 

[Luke]

There's a reply and a half!!!

Given the space you've got Al, could you put the blasting and painting boothes at opposite ends of the barn? having them close together does sound like asking for trouble.

 

[rtbcomp]

At put the blasting booth at the downwind end!

 

[astro_al]

Thanks RTB - knew I could count on you!

Ok, thats given me something to chew on. Some really great tips in there.

I'm thinking about putting a raised grill floor so I can collect the crap beneath. Gonna be a nightmare if I want to change media - maybe I never would..?

An i-beam / hoist might also be a sensible addition I think.

Materials for walls? Chipboard lined with rubber? Stainless sheet?

It is, luckily, at the downwind end. To be honest, the spraying I do is never that critical, and the place is full of plasma dust / forging mess / concrete dust etc anyway, so a double walled 'cubicle' is probably taking 'reasonable' steps to control dust. I will do the same for spraying.

No doorbell, no problem.

Cheers, Al.

 

[rtbcomp]

I was thinking of a sloping floor beneath the mesh and rake the stuff to the front, or a system like they use to clean out battery cages. An auger to lift the media back into a sieve would save a lot of backache!

I'm going to line my walls with steel from dishwasher inner shells, these will reflect the light. Wood and its derivatives will wear away. Dark rubber will absorb light. Paint will wear off, also you want to avoid paint in case it rubs off onto stuff you've just blasted.

If you fit a hoist I'd use a simple one, complicated mechanisms will jam up with dust & media. I like those chain hoists with a double unequal pullies at the top, they stay put when you let go of the chain.