Any sandblasting experience around?

I recently bought one of the $100 small blasting cabinets on eBay with the intention of using it to clean up car parts. I did one 4.0 throttle body over the weekend with glass bead and it was ok but I was hoping for much better results.

Question is will a better gun make any difference or do they all pretty much perform the same?

I have a small 110v Craftsman, 100 psi, 6 gal compressor. I know that I will not get pro results with that compressor but will a better gun make any difference at all before I spend the money?

Thanks

you need a bigger compressor most likely

sounds kinda small for a blaster...they eat gobs of air

Define poor results? Did it fail to remove material? Did it leave a crappy surface?

I run an 80 gallon tank with a 6 hp compressor. In my experience, that is about the minimum for good blasting.

Sandblasting also requires good clean, dry air. So a water separator/filter close the point of use would likely help.

I've seen old_man's air compressor. I don't think its a "true 6HP" probably a 3.2-3.5 HP / 6 HP peak that makes 10-11 SCFM @ 90psi. Tom I just don't want to scare the guy into thinking he needs a mammoth air compressor...

Having said that, guys that do heavy sandblasting are known to forgo electric altogether and get a used diesel tow behind that can run jack hammers... Cummins 6BT & 185 CFM. Of course that's more than they need, but can often be had for less than the electric setup after figuring in cost of compressor & wiring.

Check the specs on the unit you already have.
These guys are on the right track, you are going to want something that can put out at least 10 cfm @90 psi

Sandblasted are air hogs, even worse than a die grinder

LOL, we run about 500 HP total of electric compressors for all our painting and sandblasting operations at the plant I manage. I use to sell professional sandblasting rigs and cabinets and rooms and compressors 40 years ago. Now I manage the operations....of a huge job shop.

I see really good answers below already.

3-4 CFM per horspower for a real 100-125 psi compressor is the norm. The Chinese started cheating 20 years ago by using a 5-6 hp motor (they cost the same as 2-3 HP motor) on a 2-3 HP compressor. They just don't over clock the compressor and run it slower (belts and pulleys) than the motor is capable of.

The guns can consume a wide variety of air volumes, that depends on the air pressure your compressor can maintain (volume it can supply at constant pressure) and the ID of the air nozzle tucked behind the abrasive nozzle. Check the air pressure gauge after blasting steady for 60 seconds to see if it has dropped from 100 to say 30 psi. If yes you need more air volume or a smaller nozzle set. You need to be able to maintain about 70-80 psi to get good cleaning with glass beads in suction blaster.

md21722 said:

Sandblasting also requires good clean, dry air. So a water separator/filter close the point of use would likely help.

I've seen old_man's air compressor. I don't think its a "true 6HP" probably a 3.2-3.5 HP / 6 HP peak that makes 10-11 SCFM @ 90psi. Tom I just don't want to scare the guy into thinking he needs a mammoth air compressor...

Having said that, guys that do heavy sandblasting are known to forgo electric altogether and get a used diesel tow behind that can run jack hammers... Cummins 6BT & 185 CFM. Of course that's more than they need, but can often be had for less than the electric setup after figuring in cost of compressor & wiring.

Click to expand...

jhc7399 said:

I recently bought one of the $100 small blasting cabinets on eBay with the intention of using it to clean up car parts. I did one 4.0 throttle body over the weekend with glass bead and it was ok but I was hoping for much better results.

Question is will a better gun make any difference or do they all pretty much perform the same?

I have a small 110v Craftsman, 100 psi, 6 gal compressor. I know that I will not get pro results with that compressor but will a better gun make any difference at all before I spend the money?

Thanks

Click to expand...

Do you have any photos or specs of the gun and hose suction set up. Once you get the right amount of air capacity to maintain good pressure, you should take a close look at the suction hose feed set up. They can be poorly designed and clog easy. Especially if the glass beads are recycled in a cabinet and junk gets in the hose-vent area. The size of the vent hole can affect the abrasive velocity too and the amount of abrasive flow which can have a huge effect on cleaning rates. They should be fine tuned and adjusted to match the nozzle orifice size.

TRCM said:

you need a bigger compressor most likely

sounds kinda small for a blaster...they eat gobs of air

Click to expand...

I failed to mention I installed an air dryer/filter assembly for using my blaster, so now moisture isn't an issue, but the air flow is since the current nozzle is too big and I have to stop & let things catch up. I need to get a smaller nozzle for mine.

TRCM said:

I failed to mention I installed an air dryer/filter assembly for using my blaster, so now moisture isn't an issue, but the air flow is since the current nozzle is too big and I have to stop & let things catch up. I need to get a smaller nozzle for mine.

Click to expand...

Or get a pressure pot version. They do ten times the work per minute for the same sized nozzle. And at 30 PSI with a pressure rig, you can get the same work done as a suction rig at 90 psi using the same amount of air. And at 90 Psi a pressure rig will clean up an exhaust section of a turbocharger to new metal while all a suction rig does at 90 PSI is polish the scale.

Congrats on the filter/dryer, we have 3 huge massive ones, high tech pressure swing molecular sieve dryers. Look something you see in a chemical plant, in fact that is where they were first invented/used). They make a huge difference in productivity. Took me 5 years to talk management into spending the big bucks, now they go bonkers :laugh3: if one goes off line for 5 minutes LOL. Also of huge importance to get good paint jobs if using real paint equipment.

Ecomike said:

Or get a pressure pot version. They do ten times the work per minute for the same sized nozzle. And at 30 PSI with a pressure rig, you can get the same work done as a suction rig at 90 psi using the same amount of air. And at 90 Psi a pressure rig will clean up an exhaust section of a turbocharger to new metal while all a suction rig does at 90 PSI is polish the scale.

Congrats on the filter/dryer, we have 3 huge massive ones, high tech pressure swing molecular sieve dryers. Look something you see in a chemical plant, in fact that is where they were first invented/used). They make a huge difference in productivity. Took me 5 years to talk management into spending the big bucks, now they go bonkers :laugh3: if one goes off line for 5 minutes LOL. Also of huge importance to get good paint jobs if using real paint equipment.

Click to expand...

How the heck would a pressure pot work in a cabinet ??

TRCM said:

How the heck would a pressure pot work in a cabinet ??

Click to expand...

Route the blast hose through the cabinet wall with a grommet seal. Also recycle the used abrasive by hand, bucket style from the bottom of the cabinet to the top of the pot (if you use reusable abrasive), or try and fabricate something like these below if you use it much. Nice group of photos there of not so common cabinets these days, but they were and are industrial work horses. The pressure pots are (were) ASME code and expensive, or where. Somebody like Northern tool or Harbor may have low cost pots from China now days. I think I have seen them there over the last 10 years.

https://www.google.com/search?q=pre...la:en-US:official&client=firefox-a&channel=sb

This guy used a 5 gallon bucket to catch the media.




Here is a write up on the difference between suction and pressure blasting. Just stumbled on it, have not read it but might be helpful for readers here.

http://azglassclasses.com/portal/comparison-of-siphon-and-pressure-sandblasting-systems/

Here is one with the pots built into the bottom of the cabinet. Something some of the guys here with shops could fab up themselves.