sand/shot blasting

[Julian]

The simple and cheap pressure pots are far more effective than the syphon feed ones,less blockages and a far better grit feed.

To all those still thinking of using sand, Forget it! Proper blasting grit is far far better for productivity, it's properly dry so less likely to clog, it's also far tougher and sharper edges so has more effect on the metal or rust for less air pressure. The used product is also easier to clean up less dusty as it doesn't break down on impact like sand does. Once you've tried it you won't go back to sand.

Where would you suggest getting it from? The tubs of aluminium oxide grit from Machine Mart would entail taking out a second mortgage if I did a whole Cat D4 with the stuff!

I often wondered how the pressure pots compared with the syphon feed ones - I always assumed that if you use the same air pressure you'll be getting the same (or similar) grit speed?

Julian.

[martyn williams]

I found the same with kiln dried sand,it takes longer to do a job,using the proper abrasives does a better job and can be reused and don't kick up a sandstorm in the garden My compressor output is 100 psi 75 cfm.
Martyn

[Stormin]

The simple and cheap pressure pots are far more effective than the syphon feed ones,less blockages and a far better grit feed.

To all those still thinking of using sand, Forget it! Proper blasting grit is far far better for productivity, it's properly dry so less likely to clog, it's also far tougher and sharper edges so has more effect on the metal or rust for less air pressure. The used product is also easier to clean up less dusty as it doesn't break down on impact like sand does. Once you've tried it you won't go back to sand.

Where would you suggest getting it from? The tubs of aluminium oxide grit from Machine Mart would entail taking out a second mortgage if I did a whole Cat D4 with the stuff!

I often wondered how the pressure pots compared with the syphon feed ones - I always assumed that if you use the same air pressure you'll be getting the same (or similar) grit speed?

Julian.

Aluminium oxide is far too expensive to use as a single use abrasive, best saved for use in an enclosed cabinet.
I've been getting iron silicate by the tonne, delivered in 25kg sealed plastic bags on a pallet from Scangrit.
http://www.scangrit.co.uk/?page_id=81
Last lot I bought was around £200 a tonne delivered. Think they do upto 1.5 tonne on a pallet so that would work out more economical.
I say around £200 a tonne as I've usually ordered a bag or two of Aluminium oxide for use in the cabinet at the same time.

As to syphon and pressure pots, the pressure pot simply ensures a more constant and reliable feed of grit down the delivery hose.
High air pressure isn't everything. Greater quantity CFM is the essential for blasting. 100 psi is more than adequate for blasting purposes, it's then down to sizing the nozzle to suit CFM and delivery hose should be ideally 3 to 5 times bore of nozzle for adequate delivery. The grit final speed is gained in the small bore venturi of the blasting nozzle.

[Julian]

[Aluminium oxide is far too expensive to use as a single use abrasive, best saved for use in an enclosed cabinet.
I've been getting iron silicate by the tonne, delivered in 25kg sealed plastic bags on a pallet from Scangrit.
http://www.scangrit.co.uk/?page_id=81
Last lot I bought was around £200 a tonne delivered. Think they do upto 1.5 tonne on a pallet so that would work out more economical.
I say around £200 a tonne as I've usually ordered a bag or two of Aluminium oxide for use in the cabinet at the same time.

.

Thanks Stormin, very useful. I'll certainly be giving that company a call in the future.

Julian.