First Time using Blast Cabinet...any suggestions?

[Starlord85]

we purchased the Central Pneumatic 40 Lb. Capacity Floor Blast Cabinet from harbor freight, and I was tasked with getting to know the equipment and figuring out what works best for the parts we need cleaned.Right now i'm cleaning off parts to ford LTD, and i'm getting a little behind because i keep having problems.

I've gone from using the making soda media, to the black diamond, to glass bead. (turns out though the glass bead really isn't what the name suggests) and I'm Using an 8 gallon air compressor. was told we will be getting 60 gallon tank soon.

I'm wondering if the humidity is affecting things as well? I seem to run into the same problem with the media just not coming out like it should. I feel the suction at the bottom of the hose, and i have the right amount of pressure, but it feels like I've spent more time trying to get the damn thing to work, than actually cleaning off the parts.

I'm curious to know if there are tips and tricks anyone might have.

 

[altersaddle]

A blast cabinet will need CFM more than gallons from your compressor. What is the CFM rating of yours?

I used to have a 5 gallon 4.5CFM compressor. It was very underpowered to run a blast cabinet, even my tiny one. It takes a few seconds for the gun to pull media out of the hopper, and by the time I got blasting I was out of air and the compressor kicked in.

I have mildly upgraded to a 20 gallon 5.5CFM unit, which is the most I can manage with my current setup. Once I have more power available in the workshop I will probably upgrade again, this time to a wheelbarrow-style electric drive high volume unit.

Make sure your air is dry. I have a small moisture trap just before the blast cabinet.

Using larger fittings can help too, although if you don't have air to deliver in the first place, that won't help.

 

[Strouty]

Humidity and moisture formt he compressor can cause issues. Using an eight gallon compressor is the main problem, the compressor is working hard and it gets hot. That heat creates moisture and then you have a vicious cycle. If you are going to do a lot of blasting, you should set up some sort of after cooler for the air and then use a water separator. The after cooler could easily be made of 20 feet of black iron pipe or copper. Depends on the skill sets you have. Search after cooler and you will get some ideas.

 

[James-W]

More CFM is better when it comes to sand blasting.

 

[Starlord85]

A blast cabinet will need CFM more than gallons from your compressor. What is the CFM rating of yours?

manual says 4.5 CFM @ 90 PSI, 5.5 CFM @ 40 PSI

 

[Cyberbear]

I used to run a small Sears portable sandblaster with a home made blasting cabinet. This set up ran very well with my three horse 20 gallon air compressor. Everything was great until the compressor needed to run continuously, after which it would put moisture into the air line to the blaster and clog up. You need a really good moisture filter or two when blasting to keep the moisture out. A really big storage tank would also help.

 

[mikeceli]

i HAVE THE hf 40 pound cabinet, also.

1 use more glass bead than HF recommends. I run 2 boxes, not the 1 HF recommended.

2 when it stops blowing bead, pull the rubber media feed hose off the gun, put the gun tip in said hose and blow air into it. This clears most obstruction. If it doesn't work and you don't see the blast of air in the media compartment, feel around in the bead for trash stuck to the media pickup.

 

[StevenMorgan]

i HAVE THE hf 40 pound cabinet, also.

1 use more glass bead than HF recommends. I run 2 boxes, not the 1 HF recommended.

2 when it stops blowing bead, pull the rubber media feed hose off the gun, put the gun tip in said hose and blow air into it. This clears most obstruction. If it doesn't work and you don't see the blast of air in the media compartment, feel around in the bead for trash stuck to the media pickup.

You can also put your finger over the outlet nozzle of the HF gun, pull the trigger and it will clear the block. No need to remove the media hose. The air seeks the path of least resistance and goes down the media tube.

 

[metalmagpie]

Sift your media. Especially if you reuse it. For a 1/8" nozzle use no coarser than 120 grit media.

Trying to sandblast with a small compressor is an exercise in frustration. When I blast outdoors I rent a compressor on a trailer. You should not exceed a 50% duty cycle on your air compressor's motor. Meaning, if your compressor is pumping more than half the time it's too small for the job.

metalmagpie

 

[Starlord85]

You can also put your finger over the outlet nozzle of the HF gun, pull the trigger and it will clear the block.

Oh yeah that was something i realized the other day. before I was taking the tube off every time. very time consuming.

 

[Starlord85]

How do you usually sift it? What do you use? I've been using this plastic mesh screen i came across. I think it use to go to a pool skimmer.

 

[mikegt4]

manual says 4.5 CFM @ 90 PSI, 5.5 CFM @ 40 PSI

I would think that you would need at least DOUBLE that output to make the blast cabinet operate properly, even without any other problems that you may have.

 

[Charles (in GA)]

You can also put your finger over the outlet nozzle of the HF gun, pull the trigger and it will clear the block. No need to remove the media hose. The air seeks the path of least resistance and goes down the media tube.

This works good.

As far as compressor size, I don't care what the specs are, you need at minimum a 18 cfm (80 gal, two stage, 5 full real hp) compressor. If you have nozzles that have orifices that are so small that your tiny compressor is able to work properly, you have a nozzle so small that you will never get anywhere with the parts cleaning.

Charles

 

[Anarius]

I have the HF cabinet with the HF media reclaimer at work, and I cheat - we have two rotary compressors with a refrigerator drier....and then I hooked the blast cabinet to the nitrogen exchanger. Works well

Seriously tho, the water in the lines is killer. I ran three separators on the cabinet when we had our old piston-pounder compressors.

I've also replaced the "gun" with a Ingersoll version...works much better. As you noted, HF "glass bead" is not....its just crushed glass. I've found Black Bull 80 grit glass bead to be the best performance / $ for general automotive parts cleaning.

 

[Charles (in GA)]

Don't use crushed glass. Lots of dust, breaks down almost on the first cycle of use, poor choice. Use real glass beads. I think I have been using 80-120 or something like that. Last I bought was from MSC or Grainger, cannot remember which.

You gotta be willing to "pay to play" on most things, and this is no exception. See Ryan's blog and thread on TP Tools cabinets.

Charles

 

[Starlord85]

which is best for aluminum or cast iron?

 

[G_P]

I have the HF 40lb cabinet and use 50lbs of the "black diamond" from Tractor supply in it. 40lbs is not enough and you keep having to smack the bottom of the cabinet to get the media to settle back down to the bottom of the hopper.
I have a 30gal 3hp single stage 2cyl compressor that can barely keep up with it. I had to mount a fan to blow air over the compressor to keep it cool during long blasting sessions. A moisture trap is a must. Mine collects a decent amount of water after every use.
I also ditched that crappy fluorescent light that came with it and put a 250 watt halogen work light in there. Much brighter and the heat generated by the light seems to help dry the media a bit if any moisture does seep in. Knock on wood, i've never had it clog up on me.

 

[ZRX61]

which is best for aluminum or cast iron?

Glass or plastic for aluminum. Plastic is more expensive, but it lasts forever, I'm still using 2x 5 gallon buckets of the stuff I bought about a decade ago. Two different types, one is melamine which is pretty hard & the other is nylon (I think).

 

[Vegaman_Dan]

This works good.

As far as compressor size, I don't care what the specs are, you need at minimum a 18 cfm (80 gal, two stage, 5 full real hp) compressor. If you have nozzles that have orifices that are so small that your tiny compressor is able to work properly, you have a nozzle so small that you will never get anywhere with the parts cleaning.

Charles

Not everyone can afford $50,000 to equip a shop like you can. What works for you is what works for *you*.

I can do the same job on a smaller compressor. That's reality. That's what works for *me*.

There are some that will insist that you need a minimum of a 20 hp compressor with a four cylinder pump running 3 phase power to be serious about the job.

It's always nice to have more power than you need, but we are limited to what we have available.

 

[rburke65]

If ya wanted to really stretch your dollar, you could probably get the job done with a wire brush....but like Charles said, most things are come down to "if ya want to play, ya got to pay". One way or another....you are going to pay. Whether its in your time, your money, or your frustration..........your going to pay. Good luck.

 

[Starlord85]

My next problem has been the gloves in the cabinet. But i'm starting to realize that buying stuff like that from Harbor Freight is "affordable" but it doesn't last very long. been through 3 gloves in 2 months.

 

[Charles (in GA)]

I can do the same job on a smaller compressor. That's reality. That's what works for *me*.

There are some that will insist that you need a minimum of a 20 hp compressor with a four cylinder pump running 3 phase power to be serious about the job.

It's always nice to have more power than you need, but we are limited to what we have available.

I was just stating the obvious, that a small compressor requires a small orifice, and that means that you won't cover much ground. I bought too big of a cabinet. I can get large stuff in it, such as a rusted front rim off my tractor. After a few minutes, it became apparent that it would take literally HOURS to get that rim cleaned off. It went to scrap metal and I bought a new one.

Charles

 

[Charles (in GA)]

My next problem has been the gloves in the cabinet. But i'm starting to realize that buying stuff like that from Harbor Freight is "affordable" but it doesn't last very long. been through 3 gloves in 2 months.

Which brings us back to the "if you want to play, you gotta pay". The TP Tools gloves will eventually rot away, after a good many years, but I have yet to wear them out, and its been several years of moderate use on them. Quality is your friend.

Charles

 

[Charles (in GA)]

Not everyone can afford $50,000 to equip a shop like you can.

Dang, I wished someone would give me $50K to spend on shop equipment. All of my stuff, with a couple of exceptions, was used, cheap, lots of shopping to get, etc.

Used two post lift, $2100 + $600 to have it professionally moved and installed.
Used portable gantry crane and chain hoist, $1450 and a 1800 mile roundtrip drive to get it.
Used Dake 25H hydraulic press, $150 and another 1800 mile roundtrip to pick it up.
Used #3 Greenerd arbor press, $150 and a 2 hr roundtrip drive to pick it up.

Well, you get the picture.

Charles

 

[Kracin]

This works good.

As far as compressor size, I don't care what the specs are, you need at minimum a 18 cfm (80 gal, two stage, 5 full real hp) compressor. If you have nozzles that have orifices that are so small that your tiny compressor is able to work properly, you have a nozzle so small that you will never get anywhere with the parts cleaning.

Charles

odd. my 33gal craftsman with 8 cfm works just fine cleaning parts quickly. must be the stars aligning or something.

 

[bmwpower]

odd. my 33gal craftsman with 8 cfm works just fine cleaning parts quickly. must be the stars aligning or something.

Depends on how long you need to work and how cognizant you are of the pressure drop and performance. I can blast a motorcycle head for a little while before my 11cfm Quincy begins to fall behind, for example. Pressure drops below 90, less bead comes out of the gun, less work is getting done, etc.

But I'll have no problem blasting a wrench free of rust.

All depends on what you're doing.

 

[Experimental Metals]

I had the same problem you did with my HF benchtop cabinet, and I put up with it for about 6 months. After that I quit using it out of frustration.

To briefly echo what others are telling you, yes...the CFM on that air compressor is going to be an issue for you. If you were able to blast continuously with a properly working gun and pickup tube, you would find out very quickly that your compressor won't supply what your cabinet/gun is demanding. Of course more CFM is better, but just as another data point, my Ingersoll-Rand is 14.5 CFM @ 90 PSI and it does the job quite well. It is not constantly running. I could see something a little smaller being adequate for occasional use. But a lot of that depends on how large the tip is on your gun, too...larger orifice = more CFMs.

Once you get the air delivery sorted out, I have a feeling you're still going to be disappointed in that cabinet. That's because the gun and pickup tube are not adequate. I'm a pretty calm and level-headed guy, but even just 5 minutes with my factory-equipped HF cabinet made me want to go punch a kitten in his big dumb face. Every time.

On the advice of some on this forum (and others), I ordered this upgraded gun and pickup tube from TP Tools. At the same time, I also happened to move up to the larger stand-up unit from HF because I found a great deal on a used one locally on CL. I only mention that because the pickup tube is designed to mount to the stand-up cabinet in the same place as the original, but the benchtop style pickups just sort of lay in the media (at least mine did). Not a big deal, just pop a couple holes and pick up some bolts/nuts at your local hardware store.

I now actually enjoy blasting again with the upgraded gun and pickup tube. In addition to the new hardware, I can see what I'm doing with the in-cabinet lighting and the vacuum/filter system I rigged up, the air is dry with the addition of a HF compressed air dryer, and the media just keeps on flowing with my larger compressor.