Need petrol compressor for sandblasting project

[DrGonzoPOW]

Ok, plans have changed once again! Can no longer use a diesel or petrol compressor and must rely upon normal 230volt house supply for power. Whats the biggest compressor you can run on 230 and would the 20 gallon blast pots run ok with a 6mm nozel ? Ta

 

[malcolm]

There's a table on http://www.mig-welding.co.uk/sandblasting.htm which might be useful for calculating nozzle size. The low end is gathered from my own experience with a 3hp compressor and another one attached.

So a 6mm nozzle is probably out. 3mm will be your max for a single compressor on 240V, and you can blast a whole car with that but it takes a while.

3.5hp compressors are on the upper range for 240V. Would need some wiring as they'll blow a 13 amp fuse on start up. Also 3.5hp is input power so you'll likely get more flow out of a decent one rather than a smaller on the Chinese have made to be very inefficient. 14CFM for a good one. Two together (not starting at the same time) would give you 28CFM.

 

[brightspark]

Ok, plans have changed once again! Can no longer use a diesel or petrol compressor and must rely upon normal 230volt house supply for power. Whats the biggest compressor you can run on 230 and would the 20 gallon blast pots run ok with a 6mm nozel ? Ta

a 6mm nozzle would require.a comp delivering 90cfm .a 3mm
jet preferably 28cfm any smaller it would peter out in use. or just run at about 50 psi which is quite useless unless u are prepaired to wait till the tank builds up pressure or add a secondary tank or even a second comp as some do on here

 

[stormin]

I think SIP do a twin motor and pump compressor. Thing is it's dearer to buy than two seperate ones ~£1300. Only advantage I can see is they are already designed to work together so won't switch on at same time, but that could easily be achieved on two seperate compressors by messing with the pressure switches.

 

[brightspark]

I think SIP do a twin motor and pump compressor. Thing is it's dearer to buy than two seperate ones ~£1300. Only advantage I can see is they are already designed to work together so won't switch on at same time, but that could easily be achieved on two seperate compressors by messing with the pressure switches.

as storming says u can get a twin motor and pump comp but 2 seperate ones would be cheaper .the advantage of having 2 is if u are using small airtools as well .its quicker to fill one small tank than filling a large one . heres a twin that i bought 75 quid not working .stripped and rebuilt it. one new motor a good cleanup and a rewire contactors timer and suplies to motor finale cost 2 days work+ £175

 

[DrGonzoPOW]

Cheers for the advice once again. I have seen the 2 pump ones one ebay for about 1200 as said and may consider one of them but i like the sound of putting 2 together. Firstly (as you know i know nothing!) how do they join together and second, if for instance i got 2x 15cfm ones, would putting them together produce 30cfm ? Thanks again

Ps, what wiring would need to be done to run a high powered 240 one ?? ta

 

[DrGonzoPOW]

Does anyone have any info/stats on these twin motor snap-on's ?? Cant find anything about them anywhere

 

[brightspark]

Does anyone have any info/stats on these twin motor snap-on's ?? Cant find anything about them anywhere

dont know for sure but with being twin i would have thought it would be 28cfm with 2 three horsepower motors

 

[DrGonzoPOW]

Yeah that would be my rough guess going on other similar types. im told its in excess of 17 cfm but that info's pretty useless

 

[Gary900r]

At one time Snap-On were re-branding Fiac compressors.

 

[DrGonzoPOW]

Can get a nice clarke one for cheap but the guy says i need 20amp blue plug supply. Can i get this without hard wiring into house fuse box ?

 

[brightspark]

Can get a nice clarke one for cheap but the guy says i need 20amp blue plug supply. Can i get this without hard wiring into house fuse box ?

what suply have u at the moment in to your garage or wherever u are putting it. eg cable size? fuse rating is there a fuse box in garage and where conected to / the minimum size cable feeding would have to be 2.5mm @20 amp max leaving no spare capacity for anything else apart from a few lights and use of socket if comp isnt running

 

[DrGonzoPOW]

I have a standard house fuse box but i cant really run anything from there to the workshop outside which currently has no power. The idea was just to run a normal 13a supply from the kitchen to outside

 

[DrGonzoPOW]

Just a quick update on this thread i started a while ago. Ended up with a decent 15cfm clarke for the time being and plan to connect another similar one together for enough oomph to blast with a larger nozzle. Here's a couple of picks of the setup so far. Check out the grit bin blast cabinet A quality idea if i do say so myself!

Still in the process of finishing it all so it can be used. Just waiting on some gloves and hoses from ebay then its time to blast. We bought some sealey blasting grit to test it with. Will that work ok or would it be too large/rough ?? Cheers for all your help thus far

 

[brightspark]

j blast superfine is the max u can use through a 3mm jet without blocking up . i think its 0.5 mm to 0.75mm. i like the cabinet have the councill missed it yet just one point wheres the ventpipe to exhaust the pressure and dust. i use 4inch on mine with a woodchip and dust extracta . that gives clear vision and gets rid of the dust .namely outside and not in the garage

 

[Robotstar5]

Check out the grit bin blast cabinet A quality idea if i do say so myself!

You wouldn't do that round here, the council have chained them all to lamp posts!
Neat solution though

 

[DrGonzoPOW]

Its still in the process of being built so the ventilation is to follow. I have an old bagless vacuum cleaner that will come in handy for that. Need to make a case for the lights inside too but it should be pretty useful once complete. Its not a council bin by the way. I knicked it from the new industrial estate where i work. there's too many for that one to be missed
Best get looking for some superfine stuff then eh. Spent 16 quid on that bag 'o grit too. Knackers!
Ill put some pics up when its done. There will be bins going missing nationwide!

 

[brightspark]

nip down b and q and get a bag of kiln dried sand about 2 quid that will get u away. just make sure u have good dust extraction as its real bad for your health and only use it once

 

[DrGonzoPOW]

dont really want to be using sand cuz of all the bad stuff i hear about it. Where can i get some j-blast from ?? Would be good if i could find a place that offers trade discount.

 

[brightspark]

dont really want to be using sand cuz of all the bad stuff i hear about it. Where can i get some j-blast from ?? Would be good if i could find a place that offers trade discount.

trouble is with supafine the general blasters dont use it its 2 fine . so just the main suppliers keep it . j blast super is available all over the country just over 5 quid a bag. min jet size is 6.0mm . if u know anyone going to immingham near hull get it direct its the transport that kills it or postage