Sandblasting talk

Bill Crowell

Well-Known Member
Joined
Oct 16, 2007
Messages
1,170
Reaction score
791
Location
Diamond Springs, CA
I've been doing quite a bit of outdoor sandblasting of large car parst with an old Tip portable blaster that has a 90-lb. pot, and using 30-mesh sand as the abrasive medium. My compressor has 10 hp. and is connected to an 80-gallon air tank.

With the 30-mesh, I find that a 1/8" blasting tip is the smallest I can use without clogging (I'm using a small tip so I can blast longer before having to wait for the compressor to re-charge the tank).

I've found that if I regulate the pressure down to 80 lbs. at the blasting pot, it still works well, I can blast longer than by leaving it unregulated (around 120 lbs.) and I don't get that big, wasteful blast of air containing no sand when I first open the blast valve, the way I do when I run it unregulated at the pot.

I've assembled an HF blast cabinet but haven't used it yet because I want to "do the mods" first and haven't got a round tuit yet. It will be nice to start using the cabinet for blasting smaller stuff because I will then be able to re-use the media.

So please tell me your experiences and words of wisdom about sandblasting!
 

Cuda416

Well-Known Member
Joined
Jun 12, 2014
Messages
2,565
Reaction score
2,407
Location
South, TX
The HF cabinet will benefit GREATLY from a metering valve. Night and Day.
 

4spdragtop

CONGRATS NORTH AMERICA!
FABO Gold Member
Joined
Aug 28, 2009
Messages
35,166
Reaction score
16,967
Location
Wasting time here
I made a cabinet out of an old chest freezer. Works good for decent sized parts. I lowered my psi down to approx 50 psi? All depends on the severity of rust. Lowering the psi also helped to be able to reuse the media.
Dust collector from Princess Auto on sale. You need something to equalize air psi, so the dust collector has dual purpose.

20220627_222545.jpg
 
Last edited:

Treblig

Well-Known Member
Joined
Oct 5, 2013
Messages
8,441
Reaction score
6,688
Location
South Texas
I made a cabinet out of an old chest freezer. Works good for decent sized parts. I lowered my psi down to approx 50 psi? All depends on the severity of rust. Lowering the psi also helped to he able to reuse the media.
Do the parts blast easier when they are blasted in a freezer (lower temperature)???:poke::rofl::rofl::rofl::rofl:
 

MoparMike1974

FABO Gold Member
FABO Gold Member
Joined
Jun 16, 2017
Messages
3,996
Reaction score
3,514
Location
Maryland
Spend some money on a decent cabinet. Scat blast are good for the money. The most important thing with a blast cabinet is GOOD lighting and a proper dust collector.
I just upgraded to this dust collector and it was money well spent. Ran the exhaust out of the building. It works about the same as their entry level collector but the difference in sound reduction is amazing. Skat Blast® USA 180-DC INSIDER II HEPA Dust Collector
I also have a small bench top HF cabinet that I used mainly for glassbeading small stuff like bolts. Best upgrade was to add fine wire inside so small parts cant fall thorough.

So you have a 10 HP compressor...is it three phase? What's the cfm? My 7.5 HP can sandblast continuous all day and the compressor cycles with a good deal of time in between. I run my big cabinet around 100-120 psi and the small cabinet at 80-90. CFM is around 25 or 26 @ 175.
You really should not have a problem with air supply on a 10 hp compressor unless its a single stage.

I need to go get my monster cabinet so I can get it set up at my house. Its around 12' long, a real beast.
I have a pressure pot but I despise outside sandblasting. Its so damn messy and even when its cool outside you still sweat balls with all the PPE on.
 

MoparMike1974

FABO Gold Member
FABO Gold Member
Joined
Jun 16, 2017
Messages
3,996
Reaction score
3,514
Location
Maryland
Using the freezer as a cabinet is very slick. Had a friend who used to keep all his auto paint and welding rods in an old fridge because it was air tight.

One issue I have with the small HF cab is the sand piles up on one side and doesnt fall down to the suction. I may build a shaker for it or just buy one. I dont know if this is an issue with the larger HF cabs or not.
 

ch1ll

FABO Gold Member
FABO Gold Member
Joined
Jun 12, 2009
Messages
1,575
Reaction score
1,044
Location
Belgium,wi
That chest freezer sure looks like a good idea. I have an old portable bucket type and I made a trial cabinet out of a cardboard refrigerator box and an old window I had. Conclusion, too small, too much dust. Need a bigger cabinet and hook up a shop vac to collect dust and media. Gravity feed works marginal at best. I also have moved to better stripping/cleaning methods. Paint stripper and an electrolysis tank.
 

ch1ll

FABO Gold Member
FABO Gold Member
Joined
Jun 12, 2009
Messages
1,575
Reaction score
1,044
Location
Belgium,wi
Killer thread 4sp. Putting one on big casters would be the shizzz I would think.
 

4spdragtop

CONGRATS NORTH AMERICA!
FABO Gold Member
Joined
Aug 28, 2009
Messages
35,166
Reaction score
16,967
Location
Wasting time here
Thanks, I'm very happy with it. Most $$ into it are all the spray bombs of Hemi Orange paint I used to paint it. Buddy Mike @2darts made me the cool "Formula S" stickers.
Cradle dimensions were a bit off(too tall) as I have to stand up high so I made a riser to stand on. It's also somewhat "tippy" you can move it around....if I had room...
Killer thread 4sp. Putting one on big casters would be the shizzz I would think.
 

ACME SS

Well-Known Member
Joined
Apr 13, 2022
Messages
348
Reaction score
389
Location
Emmett, Idaho
Using the freezer as a cabinet is very slick. Had a friend who used to keep all his auto paint and welding rods in an old fridge because it was air tight.

One issue I have with the small HF cab is the sand piles up on one side and doesnt fall down to the suction. I may build a shaker for it or just buy one. I dont know if this is an issue with the larger HF cabs or not.
Did your friend keep the refrigerator on to keep the paint cool? Cause I can see the advantage of that for sure. As for welding rods, it depends on what they are but 7018 stick rods for example need to be kept dry so usually they are kept in a rod oven at around 150*f. Pulling them out of a cold fridge would defeat the purpose as they would condense moisture on them.
 

ch1ll

FABO Gold Member
FABO Gold Member
Joined
Jun 12, 2009
Messages
1,575
Reaction score
1,044
Location
Belgium,wi
No fridge off for storing welding rods. We used one at a place I worked at like that. As for the oven deal, I have placed them in an heated oven after turning said oven off and let them dry out any moisture that way over night. Another way I have seen is placing them in small metal toolbox with a 100 watt incandescent light bulb mounted inside. That will keep them dry.
 

Tooljunkie

King of cobble/master of the broken bolt
FABO Gold Member
Joined
Jul 22, 2017
Messages
22,288
Reaction score
26,173
Location
Manitoba
I picked up a used industrial cabinet with a dust collector and filtration system. The gun that was in cabinet wasnt great, i picked up one with assorted orfices and nozzles.
And glass bead works about the best. I run around 70 psi.
 

ACME SS

Well-Known Member
Joined
Apr 13, 2022
Messages
348
Reaction score
389
Location
Emmett, Idaho
I picked up a used industrial cabinet with a dust collector and filtration system. The gun that was in cabinet wasnt great, i picked up one with assorted orfices and nozzles.
And glass bead works about the best. I run around 70 psi.
I used crushed glass for an old pickup cab and did not have any distortion. Very economical. For really crusty stuff black beauty works pretty good...not sure what it is to be honest.
 

Bodyperson

Pedal to the metal
FABO Gold Member
Joined
Nov 26, 2015
Messages
7,803
Reaction score
10,485
Location
NW MONTANA
I used crushed glass for an old pickup cab and did not have any distortion. Very economical. For really crusty stuff black beauty works pretty good...not sure what it is to be honest.
Its copper slag. Good stuff.
 

Bill Crowell

Well-Known Member
Joined
Oct 16, 2007
Messages
1,170
Reaction score
791
Location
Diamond Springs, CA
Spend some money on a decent cabinet. Scat blast are good for the money. The most important thing with a blast cabinet is GOOD lighting and a proper dust collector.
I just upgraded to this dust collector and it was money well spent. Ran the exhaust out of the building. It works about the same as their entry level collector but the difference in sound reduction is amazing. Skat Blast® USA 180-DC INSIDER II HEPA Dust Collector
I also have a small bench top HF cabinet that I used mainly for glassbeading small stuff like bolts. Best upgrade was to add fine wire inside so small parts cant fall thorough.

So you have a 10 HP compressor...is it three phase? What's the cfm? My 7.5 HP can sandblast continuous all day and the compressor cycles with a good deal of time in between. I run my big cabinet around 100-120 psi and the small cabinet at 80-90. CFM is around 25 or 26 @ 175.
You really should not have a problem with air supply on a 10 hp compressor unless its a single stage.

I need to go get my monster cabinet so I can get it set up at my house. Its around 12' long, a real beast.
I have a pressure pot but I despise outside sandblasting. Its so damn messy and even when its cool outside you still sweat balls with all the PPE on.

I'm really hoping, MoparMike1974, that I'll be able to modify the cheapo Harbor Freight blast cabinet so it will work as well as a more expensive one. We'll see if that happens.

I'm using two 5-hp single phase compressors plumbed into a good-sized storage tank, each compressor having a one-way valve to isolate it from the other. Each compressor is rated at 9.25 CFM at 90 PSI, so I guess the total would be 18.5 CFM.

Although I can't blast continuously, my outdoor sandblasting rig really kicks butt. It is much faster than any cabinet blaster I have ever seen, but it goes through a lot of sand and air to do that. I can blast for about 5 minutes before letting the tank re-charge, by which point I'm ready to remove the hood and respirator and take a little rest anyway. I can blast quite a bit of surface area during each 5-minute period, and since I'm doing big parts right now that wouldn't fit in the cabinet, I'm pretty happy with the way the sandblasting is going at the moment.
 

Bakerlite

Well-Known Member
Joined
Nov 12, 2007
Messages
5,019
Reaction score
2,621
Years ago I made one like this...Cheap as!!!

Blast cab.jpeg
 

MoparMike1974

FABO Gold Member
FABO Gold Member
Joined
Jun 16, 2017
Messages
3,996
Reaction score
3,514
Location
Maryland
The cabinet is only a small part of a well working blasting setup. You need sufficient volume of air, dry air, good lighting and a good dust collector. The cabinet itself is the least important part. So yeah the harbor freight cabinet will be fine but the outcome will vary depending on the rest of the setup. When you have a good setup it actually becomes enjoyable to sandblast. I literally will blast for 4-6 hours straight sometimes. Legs get tired from standing and my hand(thumb) cramps really bad when holding small parts.
 

Bill Crowell

Well-Known Member
Joined
Oct 16, 2007
Messages
1,170
Reaction score
791
Location
Diamond Springs, CA
So I'm getting pretty tired of driving over to Home Despot to buy bags of 30-mesh sand (they aren't that cheap, either), and would like to recycle some of the veritable sand dune I've got in my outdoor sandblasting area. I propose to make a filter similar to the one this fellow does on youtube:

DIY Sandblast Sand Drying and Screening - YouTube

He's using plastic window screen for a filter, but the abrasive media he's using is ground walnut shells, which I believe is finer than 30-mesh sand. Would anybody have a suggestion about what kind of screen I should use for 30-mesh?
 

Tooljunkie

King of cobble/master of the broken bolt
FABO Gold Member
Joined
Jul 22, 2017
Messages
22,288
Reaction score
26,173
Location
Manitoba
My buddy bought one of those ford v8 type compressors. I fixed it up and the amount of air it makes is almost scary. He was planning to do some blasting,but the project dead-ended.
 

Bill Crowell

Well-Known Member
Joined
Oct 16, 2007
Messages
1,170
Reaction score
791
Location
Diamond Springs, CA
My buddy bought one of those ford v8 type compressors. I fixed it up and the amount of air it makes is almost scary. He was planning to do some blasting,but the project dead-ended.

I'll bet that the healthy 225 slant six that I've got in my shed could power a pretty big compressor, too, Tooljunkie! I've thought about that project often, but I really don't need such a powerful compressor. I just WANT such a powerful compressor!
 

MoparMike1974

FABO Gold Member
FABO Gold Member
Joined
Jun 16, 2017
Messages
3,996
Reaction score
3,514
Location
Maryland
You can lay out plastic sheeting to collect your sand and then sift it through some screen to re-use it. Its a lot of extra work but sure beats buying a bunch of extra sand.
 

Bill Crowell

Well-Known Member
Joined
Oct 16, 2007
Messages
1,170
Reaction score
791
Location
Diamond Springs, CA
I blasted quite a bit yesterday, but I got quite a few nozzle clogs and the nozzle was shooting out some water, so I'm going to mount a sub-micronic cyclonic filter where the air enters the blaster pot.

I can easily braze or MIG-weld something up from scrap pieces of steel in my junk box, but I'll be dipped if I can figure out how to mount the danged thing! (see picture attached)

Would any of you have any ideas about how to make a mounting bracket? Thanks again.

air filter bracket.jpg
 

Bill Crowell

Well-Known Member
Joined
Oct 16, 2007
Messages
1,170
Reaction score
791
Location
Diamond Springs, CA
Yesterday I tried to blast but the nozzle kept clogging. After clearing the clog about 10 times, nothing would come out of the nozzle, so I gave up for the day and later did a visual inspection of the bottom tank valve where the sand and air mix. The mixing valve was totally packed with sand, but I think what was causing the clogging were these large flakes of hard, gray material that were mixed in with the sand. I have no idea what those flakes were, and I never put them in there. Maybe they were some kind of reaction between the sand and the inside of the tank? I cleaned the tank and the mixing valve thoroughly, got rid of all those gray flakes and filled the tank with clean sand. I also tried opening the mixing valve only after opening the blast valve (i.e., keeping the mixing valve closed until after opening the blast valve). This seemed to work very well. I got a lot of blasting done today with no clogs whatsoever. I am still wondering what those gray flakes were, though.
 

Top