Up until now, I've mainly used my media blaster for small items that only took a minute or two to blast, but I got some trailing arms recently and now I'm starting to have problems I never noticed.

First, I know my compressor is too small, but usually I just have to wait for it to catch up, annoying but it works. Now I seem to be having trouble picking up media. I have a hard plastic tube roughly 2ft long going through the grate into the media, then another foot or some flex tubing to the gun.

It grabs some media, sometimes more than others but I'm not sure where I'm lacking. I just changed to the hard tube/flex set up, before I just had flex tube directly into the media container.

Is it just the compressor is too small? Any way to help pick up media better?

This is the blast cabinet I have:
Click to view attachment
And this is like the compressor I got:
Click to view attachment

Do you have a good Water Separator and drain in the air supply line? Also make sure to drain your compressor often...MOISTURE is the enemy of blasting....


Good Luck,

Steve

I have the same compressor and have used it for media blasing as well. It really is too small for this type of job, and because it works so hard it just compounds the moisture problem. It takes very little moisture to start interupting the media flow. I have and will again piggy backed two compressors and it gave me much improved capacity, but I still need to get better moisture control for the exact same project in the near future. I have and use a syphon style gun and also use a HF pressure pot which by nature is more of a direct feed to ANY moisture in the line.

Also as the nozzle tip wears you will loose air velocity that creates suction to pick up the media.

I do have a water separator, but not exactly sure how well it works. I did catch some media and looked but didnt see any moisture, but obviously that isn't a scientific way to check.

I figured it might be the compressor lacking, so looks like I have a new christmas wish list

There is a relatively rcent thread discussing compressors. The dual stage is generally preffered for large volume jobs $$$$$

A little trick McMark taught me and apparently, he learned it from Mr. Roadglue...

When it stops picking up media, hold your hand over the tip and let it build up pressure then, quickly release it.

and keep it plugged and let it blow out through its pick up tube.

I have the same hf unit and it occasionally clogs up ..... usually related to moisture especially on humid days. Have a good moisture separator, When it clogs, it always seems to be in the gun head. I remove the nozzle and blow compressed air back through the nozzle and line going into the medium. It's apparent where the glob of wet medium is . hope this helps. I like this HF unit better than the expensive Eastwood unit I had.

Please think about moving your media storage to the top of the blast cabnet in a bin. hopper or pressure pot type container. This puts gravity on your side and you do not need to build suction to bring media up to the gun, tube or what ever you are using. You will only be using the air to power the output of media. This works as I have used this set-up for years with no problems at all. You can also look at reducing the dia. of you output to restrict air flow and improve pressure. We have used play sand for mild steel, Glass beads for alloys and walnut shells for plastic and rubber pasts at low pressure with great results.

I myself would not try to blast trailing arms with beads. Beads are more for just removing paint or giving a very mild texture to soft metals and cleaning paint off of fiberglass. Sugar sand is what I use to clean mild steel thats rusty or has paint on it. Sand is much faster. When the gun stops up put your other hand finger over the nozzle and blow the tube clean. Sometimes a piece of paint or rust flake gets in the way of incoming sand. You need a good moisture trap. My compressor drops to 85 psi and it makes blasting much slower. If I am going to be blasting all day or for several hours I hook up a extra compressor to the supply line. I have a big compressor for outside blasting but it cost to much to run daily for little stuff. I try to get by with just a 5hp 120 psi 220 single phase compressor when I can. I hook another portable 5hp 120 psi 220 single phase compressor up for extended blast cabinet use. They both put out 15 - 17 cfm at 120 psi though. I also use carbide nozzles, they don't wear as quick but cost more. I use skat blast stuff.

I disagree with Charlie. I keep glass bead only in my cab and use it constantly for rust removal. In the case of deep pitted rust I do use the big unit, as the glass bead wont get really hardend scale off as well, but for 80% of the rust, the glass bead does just fine.


2nd. In addition to blowing back through the gun, when the media sits for a while it will compact. This happens worse in humid areas, but does happen just as well in non humid areas. Thikn of it this way. You have a 1/4" max diameter tube trying to pick u 50 lbs of media from the BOTTOM of a trough. That media (particularly when not use often) will compact in the bottom from the weight alone, regardless of moisture. Shove your hand down to the bottom and mix the media up, thus breaking up clumps, This should help, but your compressor is still on the small side

Putting your hand firmly over the nozzle to back pressure the system and blow out the debris is pretty normal for most blasters and should be done regularly. I highly recommend putting a fine mesh screen on the top to catch small debris (paint etc) that would plug the nozzle.

Also, the cheaper cabinets have cheaper nozzles. As sand comes up through it erodes the porcelain nozzle and eventually won't pull suction. Unscrew the tip and take a look. Invest in a good nozzle and a foot pedal control and life will be good.

Glass beads leave a nice finish but since they are round they don't cut well.

Aluminum oxide is sharp and cuts much faster and the finish won't be as nice, ideal for paint and rust removal though.

I compromise and use a bag of each. It cuts fast and leaves a paintable surface.

i turned mine into a pressure feed system. now my media has constant flow. no more rocking, banging, kicking the cabnet to get the media flowing. i just open the valve and it flows until i shut it off or run out of media. it takes the dread out of using the blaster. and cut my time in half. well worth the time for this mod....

At the bottom where the gun picks up the media, there should be a small air breather tube going up above the media. . the gun suction will pull the media and some of the air which helps the media flow thru the media hose faster. .
Also, you don't really want to use a dual or 2 stage compressor for blasting. . . 2 stage compressors deliver higher pressure but lower volume. . they are better for air tools that need higher torque like an impact gun. . a single stage compressor will top out at about 135 pounds but will produce higher cfm. . . so it will keep up with the blaster better. . Most blasters will need around 16 cfm to work effectively. . anything lower and you'll see the compressor struggle to keep pressure.

This is a repeat of what others have said and i find the same thing all the time. . . I always seem to notice when the gun stops working well. .I then stop the air and see if media dribbles out the gun. . . If not, you probably have an obstruction in the media tube. . . Put you finger over the gun hole and give it a blast of air. . . the air will blow out the media tube and whatever was the blockage. .usually a chunk of paint or something you blasted off already. . You can stop some of that by putting a sheet of screen on you inside tray so the media has to sift thru it. . and it will catch the big parts of crude. .

Is the pick up tube secured at the bottom of the cabinet? Mine wasn't and everytime I raised the gun the pick up tube would be sucking air. A simple conduit/cable tie down clamp securing the p/u tube to the bottom was helpful.

Couple of thoughts

I have the same HF blast cabinet. Had similar issues till I dialed it in/read instructions...

How much media do have in the blaster? Too much and it won't pull the media because of weight

Second, how much pressure are you running? Some media powderizes with too much pressure.

I have a water filter and have a regulator on the blast cabinet set at 70 psi

I duct taped a worn out orbital sander to the top of my cabinet. I didn't know about holding your finger over the tip.

Paul has a good point. Mine seems to clog more as the media gets older and full of shittage that I blasted off of some nasty part...

I have the same cabinet. I have 2 inline water traps. 1st one is at the compressor. It is a 80 gallon 6 hp compressor set to run a 90 PSI. The second trap is at the cabinet. Do not use more than 30 lbs of glass bead at one time. The weight will bog down the intake and second the bead wears out after about 20 hours of blasting. Drain the water from the compressor, and water traps every hour of use. I do not think your compressor will handle the job.

Brett, before you go run out and buy a new compressor, a couple things you should consider since almost any compressor will work. The question is how long at one time do you want to blast continuously?

You shouldn't run too much pressure with glass beads as they will just break down faster and become dusty so you don't have to run a 2 stage. I run an old 50's era 2 stage commercial compressor at 140 psi in my system but it's regulated way down at the blast cabinet. The compressor is slow but a workhorse. Sometimes running more pressure just wastes air and destroys media. If speed is essential, run aluminum oxide since it cuts so much faster.

A small cabinet typically means small parts that don't take too long to blast. Blast a part and walk away allowing the compressor tank to fill up. Storage tank is the key as well as a proper functioning system so it doesn't waste air. Although I have an old 5 hp, the tank is very large and I can blast most any part before I run out of pressure but my nozzle probably cost as much as a HF cabinet and very efficient in pulling up media.

I don't use a water separator (although I probably should) and have not had problems....depends on the humidity in your area.

Run your compressor at the highest pressure you can and regulate it down to get longer blast times.

If you give me a shout Brett, I'll come over and take a look as I am in Roseville frequently

Also, if you lay window screen (metal type) across the top of the media, it will catch the debris and not get destroyed by the blasting since it's below the table

You could also try switching to aluminum-oxide (sapphire) as a blast media. It can be used more than glass bead or silica sand before turning into powder. Once your media gets too fine, it will begin to clog as you are experiencing.
It is more expensive, but lasts longer than other media and doesnt have quite the moisture problem.

Stu

I am running aluminum oxide, it works great but picking it up has been my problem.

I'll try some of the suggestions here and see how it works. It has worked great for what I've needed so far but I'd like to expand to bigger/better, maybe even start some side work because I enjoy media blasting so much:)

Thanks guys

I am quite an idiot. I clicked on this thread thinking I'd find information about playing digital media through the stock stereo system.