TheSamba.com :: View topic

Sun Dec 25, 2016 2:30 pm

I'm thinking of getting a sandblast cabinet but I'm not sold on any of the ideas to remove the dust from the system. Using a vacuum and a 5 gallon bucket of water to catch the dust just doesn't sound logical to me. My question is if this is possible: just use some sort of vacuum to remove the dust and then vent the exhaust hose outside and into a large "sock" like item to catch what ever dust would accumulate. The videos I've seen of guys using a shop vac & a bucket of water looks like so much extra work, and it was clogging his shop vac. Why must water be involved? Why not some kind of dry filter system? I've seen dryers where the exhaust is vented inside and they use pantyhose to catch the lint all the while the hot air from the dryer helps heat the basement. I would think a similar system would work for a sandblast cabinet right?

Sun Dec 25, 2016 2:55 pm

I picked up a used cabinet from a guy selling VW parts, for like $100 bucks, It came with a light and a fan and a vent. But turns out it's useless without a high volume compressor!

Sun Dec 25, 2016 5:42 pm

If the cabinet was sealed ,wouldn't the air pressure from the gun force the lighter matter out a vent? What about using a vacuum to push the debris out?

Sun Dec 25, 2016 7:06 pm

When I worked in a garage years ago we had a rather large sandblast cabinet and there was no water to catch the dust. There was a big "sock" on the back that caught the dust. This was a large cabinet, not like the one Harbor Freight sells. Much bigger and more powerful. Anyway, you need some type of system to suck out the dust which "floats" and hinders your view, while the media is heavy and goes to the bottom of the cabinet. It gets real dusty inside that cabinet and you need some type of system to suck out the dust or you wouldn't be able to see what you were doing.

Sun Dec 25, 2016 7:14 pm

Danwvw wrote: I picked up a used cabinet from a guy selling VW parts, for like $100 bucks, It came with a light and a fan and a vent. But turns out it's useless without a high volume compressor!

That's one of my concerns too. I don't think my air compressor is strong enough to operate one. I guess it's time to upgrade my compressor first. :(

Sun Dec 25, 2016 7:29 pm

For home use I would put up with the dust. :D

Keep in mind that if you use a high pressure or pressurized blaster ,it distorts sheet metal that you are cleaning. If you want to go over a 5hp compressor motor ;which you should, you can only go up to about a 6.7 or 7 without going three phase from what I have read and I have yet to find one.

I have siphon blasted with a 5hp compressor without distortion but I have started a phosphoric acid regimen and I'm totally converted on the use of it as a hobbyist. It's not as fast as blasting though. If you have the time to let phosphoric acid soak a few days it can't be beat.

Sun Dec 25, 2016 8:01 pm

What are those guys that blast with walnut's using?

Sun Dec 25, 2016 11:41 pm

Zero blast and peen cabinet I use has 8 filter elements. They are like a long sock, maybe 5 feet long. Each element only costs about 20 something$ Should last 5-10 years in daily use.
I think three or four of these filters would do ok for a small setup.
Zero now owned by clemco industries

Mon Dec 26, 2016 7:42 am

I am a big fan of the 5 gal. bucket dust catcher. The idea is make two holes in the lid of your bucket. I used white pvc fitting from HD, that fit the diameter of my ShopVac hose. One of the holes / fittings is a short right angle, basically through the lid, turn 90' and stop. Your vacuum is applied here. The second hole / fitting is basically a dip tube that extends into the bucket to a height just above the water line (2" of water is lots). The hose that connects to the dip tube is attached to the side of your blast cabinet. Because you're taking air out of the cabinet at a rate that will exceed that of your sand blast gun, you need to put another hole in the cabinet to allow an air balance. The size of your ShopVac will determine how much makeup air you need.

Why the water? When you apply the vacuum to the short 90, the dust rushes in the dip tube and hits the water, pulling the particulate from the air. The resulting fine particles are few and your ShopVac filter and motor will last a lot longer.

I used to vent with my ShopVac only and I would fill the canister and plug the filter very quickly, now I can blast for many hours before having to empty the vacuum.

Well worth the effort in my opinion.

Mon Dec 26, 2016 7:44 am

theKbStockpiler wrote: For home use I would put up with the dust. :D

Keep in mind that if you use a high pressure or pressurized blaster ,it distorts sheet metal that you are cleaning. If you want to go over a 5hp compressor motor ;which you should, you can only go up to about a 6.7 or 7 without going three phase from what I have read and I have yet to find one.

I have siphon blasted with a 5hp compressor without distortion but I have started a phosphoric acid regimen and I'm totally converted on the use of it as a hobbyist. It's not as fast as blasting though. If you have the time to let phosphoric acid soak a few days it can't be beat.

I am the same way. I find that using a dedicated and careful chemical method for about 90% of stripping and derusting I do.....keeps me from buying a compressor larger than,I have money or wiring for.....to get into sandblasting/media blasting that I can work my way around with less risk to parts.

About six years ago....I had a harbor freight sandblast cabinet.....it was OK as far as the cabinet.....but the syphon gun had to be tweaked and worked with to work smoothly....and I could only really use it at work on their big compressor system. I left it to them when I left that company.

I did a good amount of work while I owned it.....but moving forward.....found out I actually did better work on the same type of parts.....chemically .....in trays and tubs.

Coming up......I am taking my fenders and doors to a local house with a stripping vat to be soaked/boiled....to get them bare. Then home to do any welding, dedicated spot derusting with acid/phosphoric acid.....the converting and priming.

Sand and media blasting is great.....but unless I have numerous cars to do its just too much investment for me....and....all I would actuallly have that needs blasting is sheet metal.....and for me the risk to the parts is to high. If I warp them there are no spares. Ray

Mon Dec 26, 2016 11:03 am

Chad M wrote: I am a big fan of the 5 gal. bucket dust catcher. The idea is make two holes in the lid of your bucket. I used white pvc fitting from HD, that fit the diameter of my ShopVac hose. One of the holes / fittings is a short right angle, basically through the lid, turn 90' and stop. Your vacuum is applied here. The second hole / fitting is basically a dip tube that extends into the bucket to a height just above the water line (2" of water is lots). The hose that connects to the dip tube is attached to the side of your blast cabinet. Because you're taking air out of the cabinet at a rate that will exceed that of your sand blast gun, you need to put another hole in the cabinet to allow an air balance. The size of your ShopVac will determine how much makeup air you need.

Why the water? When you apply the vacuum to the short 90, the dust rushes in the dip tube and hits the water, pulling the particulate from the air. The resulting fine particles are few and your ShopVac filter and motor will last a lot longer.

I used to vent with my ShopVac only and I would fill the canister and plug the filter very quickly, now I can blast for many hours before having to empty the vacuum.

Well worth the effort in my opinion.

I understand the theory behind water being used. What I question is the extra work that is involved in it. Buying & building the system, checking the water level, emptying the water/sludge, cleaning the shop vac... I'm looking for some type of system where you just need something to create a vacuum that blows the dust into a filter/sock, which for me would be outside so no dust would be in my garage. Put a big enough sock/filter on there and you won't have to deal with checking it for quite a while. I've seen videos where guys use the 5 gallon bucket/water/shop vac setup and they claim they have to check the system every 2 hours of blasting. I'm trying to make this as maintenance free as possible.

Mon Dec 26, 2016 11:34 am

I'm using the large standing Harbor Freight media blast cabinet. I'm only running a small 110 volt compressor. This cabinet and gun doesn't have a large CFM demand. It keeps up with the gun pretty well. I have a small 5gal wet/dry vacuum pulling the dust into it. W/out it, the dust can be so thick that you can't see the part you're blasting. I have to remove the filter from the wet/dry vacuum every couple of hours and knock and blow the dust off it. I've found that i don't use the cabinet that often so it's not a big deal.

I think the cabinet works great overall. It will strip engine tin quickly if you use a good media in it. It removes ALL the rust as well w/out warping anything. It's also great for small parts, etc..

For bigger items that require rust or paint removal that won't fit in the cabinet, I've tried all the stripping pads, rust removers, etc.. Frankly, I will take them to get professionally blasted vs. going that route again.

Mon Dec 26, 2016 4:14 pm

Perhaps you need to check out some of the dust collection solutions that woodworkers use?
http://www.woodcraft.com/category/dc/dust%20collection.aspx
I use a cyclone lid on a bucket to reduce the amount of dust and shavings getting to my shop vac. The Dust Deputy looks interesting.

Mon Dec 26, 2016 6:51 pm

Q-Dog wrote: Perhaps you need to check out some of the dust collection solutions that woodworkers use?
http://www.woodcraft.com/category/dc/dust%20collection.aspx
I use a cyclone lid on a bucket to reduce the amount of dust and shavings getting to my shop vac. The Dust Deputy looks interesting.

That does look interesting. Thanks.