Portable Sand Blaster - moisture, or new Gun
- Thread starter PeteNZ
- Start date
Spareparts
Well-known member
Try sifting the media, a 6" tea strainer should do the trick, I have a 100lb. pressure pot and use playground sand from HD
run the bag of sand thru the strainer and blast away
run the bag of sand thru the strainer and blast away
Dan in Pasadena
Well-known member
Playground sand is silica sand and dangerous as hell for your lungs unless they've changed it.
EDIT: Looks like it has changed. It's no longer the old (almost) pure white silica sand. Though silica sand is still available. It's now called quartz sand, white sand or industrial sand.
EDIT: Looks like it has changed. It's no longer the old (almost) pure white silica sand. Though silica sand is still available. It's now called quartz sand, white sand or industrial sand.
Hello,
Thanks for the reply.
I will try the strainer trick and report back.
Q: How will the strainer help?
Cheers
Pete
Spareparts
Well-known member
By sifting the media you remove the larger pieces of the media that plug the orfice/nozzle up
I was the Quality/Lab Director for a mining company that produced silica sand. Quartz sand, white sand, industrial sand are all silica. Be sure to wear a good respirator at all times you are using this sand. A dust mask is not enough. All the employees at my plant had yearly chest x-rays, as well as breathing function tests. I would still use it for sandblasting, just use common sense and protect your lungs.
finn
Well-known member
I switched to the black coal slag media. A lot less dust is generated and I can actually see in the cabinet. My nostrils stay cleaner.
There are a couple of grits available. The finer grit should work better if you have a gun plugging issue, assuming you are sifting out the rust particles.
There are a couple of grits available. The finer grit should work better if you have a gun plugging issue, assuming you are sifting out the rust particles.
racecougar
Well-known member
Whatever media you choose to use, you really should still wear a respirator.
OP, what are you using to provide dry air? The media is bone dry, too, right?
In my limited experience, there are a couple things.
Larger pieces can clog the guns. Moisture from the compressor can clog the guns. When there's no metering valve, you can end up with too much media being siphoned into the gun and cause a clog. If you do have a metering valve, it's not necessarily good to have it wide open. Any gun can only handle so much media.
Larger pieces can clog the guns. Moisture from the compressor can clog the guns. When there's no metering valve, you can end up with too much media being siphoned into the gun and cause a clog. If you do have a metering valve, it's not necessarily good to have it wide open. Any gun can only handle so much media.
Hi, at this stage I only have a inline moisture filter. It's now sitting just before the gun. I did have it at the compressor outlet.
It's a straight ---- through type. Maybe I need the T shaped one?
Edit: the media just sits in the hopper, I was unsure what else to do with it.
Now I'm thinking I could dry it Some how and put back in the buckets it came in, until I use it next?
Last edited:
For pressure pot blasting, I use blasting sand. I've never tried just generic sand, so I'm sure that's full of ****. With blasting sand I've never had any ****, but I do run it thru a screen so that I can break up any clumps caused by moisture.
For cabinet blasting I use aluminum oxide or glass beads and just dump it into the cabinet.
For cabinet blasting I use aluminum oxide or glass beads and just dump it into the cabinet.
BillK
Well-known member
Hi there, Thanks for the welcome.
I'm am using these at the same time. The blacklisted one I'm not sure about now.
I've just sieved all this, about 10kg.
Attachments
BillK
Well-known member
That should work ok. Like the others said make sure to run it through a screen and it has to be very dry. I have a similar blaster but have not used it in years because I have a big cabinet at my business. I dont remember having problems with it but I only did some very small jobs with it.
driftpin
Well-known member
I've used a pool screen, the one you clip onto your aluminum pole to remove debris in the pool. I just rest it on-top of a 5 gallon bucket and pour away. I am no expert but you probably will get better results if you sift the media each time you're going to fire up your compressor for blasting. It doesn't take much time, and I bet you will notice how it helps vs not doing it, and becoming frustrated.
Jazz1
Well-known member
Sifting the sand and a water separator on air supply keep the media flowing
Mike65
Well-known member
I have one from Eastwood, that was called blast from a bucket. Bucket of sand & put the suction hose in the sand & hook an air line to the gun & blast away. The sand had to be dry or the gun would plug up. Worked good for me.
Hard to tell from the picture, but that's kind of what I assumed you had. They can work ok. Yes, there might be a hole there where the hose connect to the hopper to allow air to mix in with the media as it is siphoned up. More elaborate setups will be adjustable so you can adjust the mix.
You garnet media might be a bit coarse for that that setup. Sifting it to get only the smaller particles should help. The moisture filter should work better at the gun, gives the air more time to cool allowing the moisture to condense a bit. Also make sure your tank is drained, the more water you have in there, the more that will get into your air.
Also, you can play with the pressure a bit, you probably don't want to be running a full 90+ psi for blasting. A lot of time your better to be closer to 40-60 depending on media and grit.
there is an abrasive blasting thread here with a ton of info and some very knowledgeable participants. Though it's dangerous cause there's some guys here with some very nice blasting setups. The envy starts to build after a bit
Jeff Ivers
Well-known member
Do you have at least 25 feet of airline/hose between your compressor, followed by a water separator before your gun? Most find it takes at least 25 feet of hose/line for the air to cool enough for a water separator to get enough moisture out of the air to prevent the types of problems you are experiencing.
Moss
Well-known member
I have had issues with different grits and trying to find a consistent setup. I see one of your materials is 30-60 grit and I looked up the other one and it looks like it might be around 20 grit. Depending on your setup you might want to try and get to a more consistent grit so you can figure out what works best. I use mostly crushed glass. It's very consistent. I know with some other materials there will random larger pieces that will my cabinet gun.
finn
Well-known member
I bought a new to me Skat 46” cabinet that included one of the screens they sell. Surprisingly, a fair amount of the medium grit black diamond doesn’t fit through the mesh.
Afternoon, here in NZ.
I have a 9 meter hose reel. That's setup between the compressor and the blast gun. Then the moisture separator/filter.
Compressors in the shed out back of house/garage. Just through the wall.
Mite try it out soon, I'll drain the compressor.
I'll post back later
Cheers for the comments people.
I have a 9 meter hose reel. That's setup between the compressor and the blast gun. Then the moisture separator/filter.
Compressors in the shed out back of house/garage. Just through the wall.
Mite try it out soon, I'll drain the compressor.
I'll post back later
Cheers for the comments people.
Hello
Last evening I used the sieved garnet and still have some of the same issues of nozzle blockage building up due to moisture. Moisture can be seen on the object being blasted, at times.
Where I have some luck is by sitting the hopper feed hose inside the hopper, sucking the garnet until it needs to be buried in garnet again, each couple of minutes.
I'm thinking of getting a T style water / moisture catcher to sit at the air compressor.
Cheers
Last evening I used the sieved garnet and still have some of the same issues of nozzle blockage building up due to moisture. Moisture can be seen on the object being blasted, at times.
Where I have some luck is by sitting the hopper feed hose inside the hopper, sucking the garnet until it needs to be buried in garnet again, each couple of minutes.
I'm thinking of getting a T style water / moisture catcher to sit at the air compressor.
Cheers
Desert rider
Member
Dry air, dry grit…. Depending on your location and the humidity outside, maintaining those two requirements can be a real challenge. The mere fact of compressing air creates moisture… damned if you do… damned if you don
finn
Well-known member
Five gallon buckets.
With the lid.
With the lid.
Jeff Ivers
Well-known member
I am not sure what you mean by T style water/moisture catcher. Around here we have in-line moisture filters (no drain) and we have either water separators or water/oil separators. I have a water/oil separator (with drains) attached right after a ball shutoff valve attached to my compressor. Then I have about 35 feet of hard air line leading to another oil/water separator. From there, I attach flexible air hose to run to whatever tool I wish to use, including a blast cabinet. The oil/water separator attached to the compressor traps a few drops of oil and a few drops of water. The oil/water separator placed about 35 feet away from the compressor catches several hundred times the amount of water. What you are proposing to do will not work to remove significant moisture from your air!
Zeke
Well-known member
Put an old style light bulb (incandescent) in your cabinet if you suspect humidity.
racecougar
Well-known member
I'll venture a guess that the shed isn't air conditioned? Is the ambient humidity high in there? What size compressor are you using?
If you're clogging up the media hose well before the gun, even after sifting it, I'll suggest putting effort toward drying out the media. Yes, you need to dry the air as well, but it sounds like your media is clogging the feed line well before reaching any compressed air.
He's using a non-pressurized hopper setup (post #11).
Zeke
Well-known member
So? The gentle heat will dry out the sand. Where the sand is makes no difference.
racecougar
Well-known member
The sand would need to be near the heat source for that to work. If he uses an incandescent bulb in a blasting cabinet, but the sand is in his portable hopper, the bulb isn't going to do anything for him.
Zeke
Well-known member
Works for me, all I can say. We're talking about 120º or so and for overnight at least. If the sand ever got wet wet, it's done.
racecougar
Well-known member
Right, if the sand is in the blast cabinet with the bulb, it could work.
My shed the aircomp sits in is purely a garden type shed, no sealed at all.
I hope to still try a water trap at the compressor end also.
Do I need shorter house for more positive suction?
My compressor is a recent purchase, 2.0hp, 40L, upto 200Lpm, free air 130Lpm apparently..
racecougar
Well-known member
That is a very small compressor for sandblasting use. You stated that the nozzle clogs up every minute or two; I'd expect it to, as pressure will drop off rapidly with a compressor that isn't able to keep up. You can certainly try a shorter media hose, but in the end, if you intend to do much sandblasting, you'll want a more capable compressor.
finn
Well-known member
Have you tried blocking the gun discharge with your gloved finger and then depressing the trigger? That usually temporarily clears the blockage so you can temporarily resume blasting.
It’s only a temporary reprieve though, and if it works you will still have to sift the media or the debris / oversized particles will again make their way to the gun orifice in short order.
It’s only a temporary reprieve though, and if it works you will still have to sift the media or the debris / oversized particles will again make their way to the gun orifice in short order.