9 replies to this topic

[sibhs]

G'day Richy,

 

I've got a pot 10 gallon sandblaster and I would guess 50KG sifted and run through twice.  Very limited experience, only used mine for 10 mins till I realised I need a bigger compressor.

 

Marty

[ryano1911]

If you don't have the equipment for it and it's still all apart get it done professionally, just before christmas I had my whole front end sand blasted primed and powdercoated black and springs red and it cost me $200 cash for everything and it looks like new.  Just make sure it's free from greese and oil otherwise you'll pay more. Oven cleaner is better than chep degreaser I've found.

[Mort]

I have the 10 gallon as well and like you found i need a bigger compressor, just went to Supercheap and got the gravity fed sandblaster for $50, just in the middle of making a blasting box to use it.

[Beans]

Here is a guide below from a sandblasting site on the consumption of abrasive to air volume through the various blast nozzle sizes.

On average the largest compressor you will be able to purchase/run on single phase 240 V is a 16 cfm compressor.

Otherwise like Azer said you will be waiting around a long time for your compressor to catch up.

Most compressors larger than this require 3 phase power.

As you can see in the chart even a 16 cfm compressor will struggle to feed an 1/8" nozzle consistently.

Dropping the blast pressure to 70 - 80 psi will also help prolong blast time before you need to wait for the compressor to fill back up but will not rip the paint and gunk off as quick.

Adding a slave tank (air receiver) will increase the volume of compressed air but take longer to fill once the pressure drops (because of the increased air volume).

To make a second air receiver find yourself an old air compressor tank (in good condition) and feed from your compressor outlet into the tank then out again to the equipment.

Just plug off any of the additional holes in the tank if they are not required.

These air receivers are also available and purpose built from compressor companies.

A water trap and filtration (after the receiver) will help to keep the moisture low in your air line so the sand does not stick together in the delivery tube after a longer period of blasting due to condensation build up.

Commercial compressors use built in refrigerated dryers to remove the moisture from the air systems.

Stand alone refrigerated units can be retrofitted (mounted to the workshop wall) after the compressor to do the same thing but are expensive.

A friend of mine purchased one for his 16 cfm compressor recently for $1400.

Size is approximately 500mm Wide X 400 H X 200 D.

He also placed primary filters (5 micron) and secondary filter (1 micron) into the system and rang up another $350 for these two units with fittings.

But now he has clean and dry compressed air for all of his paint and blasting work in his shed.

 

Nozzle Size

Air Consumption

Abrasive Consumption

Blast Hose Size (I.D.)

Air Hose Size (I.D.)

1/8" #2

21 CFM @ 100PSI

55KG/HOUR

1/2" 12MM

3/4" 19MM

3/16" #3

45 CFM @ 100PSI

120KG/HOUR

3/4" 19MM

1" 25MM

1/4" #4

81 CFM @ 100PSI

225KG/HOUR

3/4" 19MM

1" 25MM

5/16" #5

140 CFM @ 100PSI

375KG/HOUR

1" 25MM

1-1/4" 32MM

3/8" #6

200 CFM @ 100PSI

500KG/HOUR

1-1/4" 32MM

1-1/2" 38MM

7/16" #7

255 CFM @ 100PSI

700KG/HOUR

1-1/4" 32MM

2" 50MM

1/2" #8

340 CFM @ 100PSI

900KG/HOUR

1-1/2" 38MM

2" 50MM

 

 

[Beans]

Here is the chart

Nozzle Size/  Air Consumption/ Abrasive Consumption/  Blast Hose Size (I.D.)/ Air Hose Size (I.D.)

1/8" #2        / 21 CFM @ 100PSI  /  55KG/HOUR                   /     1/2" 12MM                 /   3/4" 19MM

3/16" #3      / 45 CFM @ 100PSI  / 120KG/HOUR                  /     3/4" 19MM                 /   1" 25MM

1/4" #4        / 81 CFM @ 100PSI  /  225KG/HOUR                 /       3/4" 19MM               /   1" 25MM

5/16" #5      /140 CFM @ 100PSI /  375KG/HOUR                 /       1" 25MM                  /   1-1/4" 32MM

3/8" #6        /200 CFM @ 100PSI /   500KG/HOUR                /       1-1/4" 32MM            /   1-1/2" 38MM

7/16" #7      /255 CFM @ 100PSI /   700KG/HOUR                /       1-1/4" 32MM            /    2" 50MM

1/2" #8        /340 CFM @ 100PSI /   900KG/HOUR                /       1-1/2" 38MM            /    2" 50MM

[sibhs]

Thanks Beans, good info there.