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julianf
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I have two 3kw compressors. Both are wired with 16a plugs to dedicated, probably, c curve breakers.
One of them (alone) will run my blaster, but the radius of the "impact zone" is very small. You would be there forever doing the underside of a car.
Ive got a landrover front axle to do. It will take some time with just one of the compressors. I need the other compressor to run an air fed mask, as the axle will not fit in a cabinet here.
Ive got some landrover bulkheads to do. I wont even attempt to do them until i fix my hydro-vane.
More air means larger nozzle size, which means that the radius of your stripping area is increased.
3kw / 24cfm (claimed) will work, but you will just be there forever.
And, as above, you will need some breathing apparatus, as the bottom of a car is not going to fit in a sealed blast cabinet.
Every time i skim this thread, people seem to be saying you need "more" and you want to battle on with what you have, or what you plan to have. Which is fine. But theres not a whole load of point in asking for advice if youre planning on ignoring everything said! : )
You will be able to strip material, but, with your current plan, it will be so very very slow that you'll just hate it.
Cheap blasting is ok for small things in cabinets. But thats not what it seems that you are trying to do.
This isnt some "gate keeper" comment - more just a warning. By all means, crack on with your plan, but what you have been told is true, irrespective of if its what you wanted to hear or not! : )
One of them (alone) will run my blaster, but the radius of the "impact zone" is very small. You would be there forever doing the underside of a car.
Ive got a landrover front axle to do. It will take some time with just one of the compressors. I need the other compressor to run an air fed mask, as the axle will not fit in a cabinet here.
Ive got some landrover bulkheads to do. I wont even attempt to do them until i fix my hydro-vane.
More air means larger nozzle size, which means that the radius of your stripping area is increased.
3kw / 24cfm (claimed) will work, but you will just be there forever.
And, as above, you will need some breathing apparatus, as the bottom of a car is not going to fit in a sealed blast cabinet.
Every time i skim this thread, people seem to be saying you need "more" and you want to battle on with what you have, or what you plan to have. Which is fine. But theres not a whole load of point in asking for advice if youre planning on ignoring everything said! : )
You will be able to strip material, but, with your current plan, it will be so very very slow that you'll just hate it.
Cheap blasting is ok for small things in cabinets. But thats not what it seems that you are trying to do.
This isnt some "gate keeper" comment - more just a warning. By all means, crack on with your plan, but what you have been told is true, irrespective of if its what you wanted to hear or not! : )
Erie Fred
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Or powerwasher with a rotating nozzle ( a large power washer) and then Phoso when done.
I appreciate the advice I've bought a cheap and nasty pot I just want to know what's the best compressor to get with the pot I have I understand it's going to take a while unlike a lot of people I don't have the funds to do what everyone is asking I'm buying what I can afford
Can understand your position totally. But you have been told by experienced people, (I sell the things for a living) the minimum you need. If that isn't doable on your budget. Then there will be a cheaper options. It may take longer, and you might have to work harder. But what you want can be done. You are very new on here, please listen to the very sound advice posted.
brightspark
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will take more than a while 
blockages water in the lines iregular grit and airflow downtime. its disheartening . buy a 14cfm comp and have a go if you have the time to spare on smaller stuff and take it from there 
get a belt drive comp as you will kill a direct drive one in 20 minutes and cook it
blockages water in the lines iregular grit and airflow downtime. its disheartening . buy a 14cfm comp and have a go if you have the time to spare on smaller stuff and take it from there get a belt drive comp as you will kill a direct drive one in 20 minutes and cook itI am listening but I just cart do what people have said I am very new to all of this and I do appreciate everyone's advice I really do as it helps out a lot but unfortunately my budget for a setup was 500 I've bought a cheap pot off eBay for 100 I'm left with 400 to get a compressor I am not to bothered about it taking longer if I had the money I would of just paid a company to do the job
I would return / resell the pot and try a needle scaler gun, rotary wire brush etc, you just can't do sandblasting in your budget.
Edit: I should say, the compressor you're looking for (minimum 18cfm, plugs into a house socket, costs £400) doesn't exist. Other methods can be accomplished without a compressor or with one that does cost £400.
Edit: I should say, the compressor you're looking for (minimum 18cfm, plugs into a house socket, costs £400) doesn't exist. Other methods can be accomplished without a compressor or with one that does cost £400.
You can't expect someone to advise your use case as there is no compressor suitable with your limitations, give up portability and get a 16 or 32 amp socket fitted you open up used options that have already been recommended. You are asking strangers to recommend how best to waste money you don't have plenty of, maybe take the £100 loss instead of potentially wasting another £400. It's unlikely that not being able to blast your floor is holding up your project, perhaps start a thread with pistures of what you are dealing with and your plans and expectations.
I run 2 relatively small compressors, a direct drive and a homebuilt belt drive to run the smallest available benchtop cabinet and I can only blast 5 seconds on 5 seconds off 15 minutes at a time with 15minutes cool down, it's slow progress for suspension and small parts some have been chemical stripped of the majority of rust. The direct drive compressor is pretty much eating itself even though it runs less than the belt drive and I haven't finished one car's worth of parts.
julianf
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....which leaves you £100 left over.
Which wont be enough to buy a set of filters and an air fed mask.
Again, everyone here appreciates what you're trying to do. The forum is populated by engineering types who like solving problems, and (from what ive seen) generally dont like burning through cash.
But there are limits.
julianf
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ps.
ive got -
one 3kw belt drive (i think i paid £150)
one 3kw direct drive (i think i paid £120, but it was 15 years back or somthing, so im hazy on it)
a devilbis mask and belt pack - who knows what i paid, it was so many years ago, £60 maybe, second hand?
a 3 stage filter set for the breathing kit. id imagine a metalwerks set is about £80, but i really dont know
then you need a trap or two for the compressor, a load of hoses, couplers, etc.
i broke a female coupler last week. it was the best part of £8 to replace at screwfix.
all of my kit, outside of the filters and the hoses, was second hand.
You can kind of get to where you want to be, ish, on your budget. But not exactly, and certainly not by buying new. Just cant be done.
edit: and a broken hydrovane. which was £240 or somthing, but the VFD to run it would be more than that new...
ive got -
one 3kw belt drive (i think i paid £150)
one 3kw direct drive (i think i paid £120, but it was 15 years back or somthing, so im hazy on it)
a devilbis mask and belt pack - who knows what i paid, it was so many years ago, £60 maybe, second hand?
a 3 stage filter set for the breathing kit. id imagine a metalwerks set is about £80, but i really dont know
then you need a trap or two for the compressor, a load of hoses, couplers, etc.
i broke a female coupler last week. it was the best part of £8 to replace at screwfix.
all of my kit, outside of the filters and the hoses, was second hand.
You can kind of get to where you want to be, ish, on your budget. But not exactly, and certainly not by buying new. Just cant be done.
edit: and a broken hydrovane. which was £240 or somthing, but the VFD to run it would be more than that new...
henry Kadzielski
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My two cents worth.
A lot of us here over the years have done or at least attempted to do something like you, in this case. I, at least have attempted to do what you are trying. Logic tells you that you need, in your case a blast pot and compressor to get the job done. It's simple get a pot, cheap one and spend the rest on a compressor. How hard can this be. Small compressor will be slow but I can do this. Sorry, but you can't @julianf has mentioned some of the other components that will be required. One point that a lot of respondents have mentioned is the run time / duty cycle of reciprocating compressors, but haven't spelled it out. Small DIY compressors can't run continuously as they will get hot and throw out oil down the air line, produce hot air, send moisture down the air line, eventually cook the reed valves and burnout the motor.
There is documentation for the size of the nozzle to the air requirement in pressure blasting setups. Rule of thumb abrasive blasting is done at 100psi at the nozzle. Any psi above 100 at the nozzle you gain 1.5% production 'speed' any psi under 100 at the nozzle you loose 1.5% production. I have seen the pic of the pot you have purchased, but there are no details as to the nozzle size. The nozzle size is the controlling factor, for the air requirements.
You say that you understand that it will take a long time, but that is you budget. I can't see what you are going to blast, the state of it, so can't comment on how long it would take, however I will tell you you will get p!!!ed of with it very shortly and realize 'what the hell am I trying to do, this will take forever, this is bull ****
If you send some photos, specs of what you have and are doing most of us here will then tell how far you are off the mark, sorry to be blunt.
My small setup is a 11kw rotary screw compressor with a refrigerated dryer driving through a No.3 nozzle (3/16"). Would this blast a car floor, yeeeees. I will be very careful. If there is just a thin coat of paint it would be OK. However if there is thick paint, sound proofing and or thick rust that will slow down the cleaning very much. I have just blasted on a boat that I have been replacing steel deck plates. The steel was new, original deck was ground back for welding, so no paint and the entire surface was about 1/4 of a car floor surface area. This took about 4 hrs with a small professional setup.
At one time I was considering buying a pressure pot grit blaster.
But luckily I read the various posts on this forum and realised the limitations of my air supply and the expense of the other stuff needed to do the job properly.
The blast pot is the cheapest part of the system. When I worked out the costs for everything else I needed it was very expensive. Certainly a lot more than your £500 budget. And this was at least 15 years ago when things were a lot cheaper.
You also need to budget for blasting grit. Please don't use sand, the health risks from using it are serious.
You also need a suitable location to do the blasting. It produces a lot of dust that will blow everywhere. So you need a tent with filtered dust extraction if its in an urban location.
As others have said, sell the pot and pay somebody to do the job. If you do a lot of the prep work yourself like removing the underseal you will keep the bill down.
But luckily I read the various posts on this forum and realised the limitations of my air supply and the expense of the other stuff needed to do the job properly.
The blast pot is the cheapest part of the system. When I worked out the costs for everything else I needed it was very expensive. Certainly a lot more than your £500 budget. And this was at least 15 years ago when things were a lot cheaper.
You also need to budget for blasting grit. Please don't use sand, the health risks from using it are serious.
You also need a suitable location to do the blasting. It produces a lot of dust that will blow everywhere. So you need a tent with filtered dust extraction if its in an urban location.
As others have said, sell the pot and pay somebody to do the job. If you do a lot of the prep work yourself like removing the underseal you will keep the bill down.
I paid a mobile blaster to do some work on my car 20 odd years ago - took him way longer to set up and then take back down, all his gear than to do the job.
Best money I spent - a quicker, better job than I could ever have hoped to do on my own. The only downside was clearing the blast media from the drive the garden, next doors drive, the road . . .
Best money I spent - a quicker, better job than I could ever have hoped to do on my own. The only downside was clearing the blast media from the drive the garden, next doors drive, the road . . .
