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View Full Version : Small bead/grit blasting setup



Sun God
10-01-2014, 11:12 AM
Sorry for what is probably an obnoxious asinine question, but as I live in a terribly corrosive environment (60 feet from seawater) I'm very very seriously looking at incorporating an electroless nickel plating process into my shop, to plate small parts and tools for corrosion resistance. But also as a finishing process for small gun and model engine parts. It's a relatively inexpensive process, but to be worthwhile needs good surface prep of parts before plating.

So I'd like to add a bead and grit blaster to dovetail in to all of this - and besides, it would be nice to have for things like removing mill scale, paint, and corrosion just generally. I've got no experience with grit blasting, don't have a cabinet, blast media, a gun, or a compressor. In general I'd also just like to add compressed air to the shop for things like tyre inflation, dusting, small air die grinder, etc.

The largest part I'm going to want to blast likely has a surface area no larger than an iPhone or similar. It's really, small potatoes stuff that I'll be relatively willing to take my time on.

I'm sick of reading the same old advice that says go out and buy a 16CFM (and $800-1200) compressor. Yes, that would be better, but I simply can't justify that level of spending on something that isn't going to be a 'use every day' type tool. So what I'd like to know is, who has practical experience doing abrasive blasting on a budget? What is your setup? How can I make the most out of a smallish compressor (I'm probably going to be able to afford something in the 12 Gallon/50 Litre size range, 5-7CFM free air delivery)? Will there be a difference in air consumption between suction and pot type guns?

flylo
10-01-2014, 11:27 AM
You could add a second air tank out of the way & by the time you used both tanks the small job would probably be done. I had a 25 gal compressor go bad so I now use the tank to roll to remote places I don't wave enough hose for outside.

Mike Folks
10-01-2014, 12:53 PM
Look at this Soda blaster, I'd thing ideal for small projects:

http://www.aircooledtech.com/tools-on-the-cheap/soda_blaster/

RWO
10-01-2014, 01:07 PM
I have a home made glass bead blasting cabinet that will take a 24" long workpiece easily. The compressor is an old 1 HP Sears unit with a 12 gal tank. It does fine with the bead blasting siphon gun which is the most air hungry tool I own. It runs continuously while bead blasting, but it maintains enough pressure to do the job, which is the same kind of use you mentioned. Do not buy an oil-less compressor as they are incredibly loud.

RWO

Bob Ford
10-01-2014, 06:32 PM
A one to three day soak in vinegar will remove mill scale, rust, and most paint.

Bob

J Tiers
10-01-2014, 09:41 PM
But blasting does a good job right now.

I have a gun with an attached bottle for grit. It's a cheapie, that I was actually GIVEN, but it is allowing me to find out what I use one for, and how much. Therefore it's highly useful. And I have done some project-related blasting.

That company has been gone for 40 years, but Sears makes, or made, a setup with a bigger grit pot, and a longer hose for the gun. Might be good, and isn't very expensive as such things go.

ulav8r
10-01-2014, 09:59 PM
I had one of the Sears guns like JT mentioned years ago. Used with a 1 horse compressor (1 real horsepower in the mid 70's) at about 5 cfm. It was just adequate for blasting a rifle barreled action. I believe the nozzle ID was just over 1/8 inch. Use a small nozzle for your small projects to maintain higher grit velocity, using a larger nozzle will reduce the effectiveness unless you have a suitable large compressor.

Rich Carlstedt
10-02-2014, 12:25 AM
I built a blaster with a 2 HP compressor ( 50 years old) and it works.
What is really important for you is to watch the gun you use !
Cheap guns have metal nozzles that quickly wear out.
The problem with that is any wear means MORE air ! And quickly too !
Get a carbide nozzle if you can and you will not see a degrading of performance
The nozzle size determines the air consumption.

Rich

quadrod
10-02-2014, 06:56 AM
I just bought a bead blast cabinet off of flea bay for just over a couple of hundred bucks, and then some 70-140 glass bead and it does a good job. It is thin sheet metal for the cabinet and when you put it together pay attention to detail. but over all does great.

Yondering
10-02-2014, 12:01 PM
My bead blaster is the cabinet-mounted Hobo Freight unit, and a 2hp compressor; it works fine for my needs, although on a longer job, like a rifle action or lots of small parts, I sometimes need to let the compressor catch up.

The cabinet is good for the price, but not high quality. If you buy one (and I would buy another), just check all the seams for sealant, and add some RTV where needed. Mine had several seams where sealant was applied, but about 1" away from the seam line so it didn't do any good.

Dragons_fire
10-02-2014, 12:14 PM
Badger Airbrush makes an airbrush size blaster that will work with almost any compressor, and i like it for small parts because its a lot easier to control than a "full size" blast gun. the trigger is an easy push so its easy on the hands while blasting lots of parts. the only issue is youre stuck with fairly fine grit since it has such a small nozzle.

forgot to mention, my blast cabinet is a clear molded "rubbermaid" bin that i siliconed ABS toilet fittings into, and then hose clamped on some rubber gloves. you can see through the whole tub, so there is no visibility issues, and eventually when the inside of the cabinet gets blasted, it would be cheap to replace.

michigan doug
10-02-2014, 01:24 PM
I have the HF portable sand blaster unit.

http://www.harborfreight.com/portable-abrasive-blaster-kit-37025.html


It's a plastic bucket with a suction gun. 35 bucks. My "2 hp" chinese coleman compressor runs it at about 95% duty cycle, meaning I rarely have to wait for the compressor to catch up. They say it only needs a 1 hp compressor, whatever that means. The gun comes with a ceramic nozzle and the trigger is pretty nice. I was impressed actually.

Since I rarely use it, I just do it outside and run it as a 100% loss system. I should build a cabinet someday...wouldn't have to be fancy.

Don't use sand (silicosis risk) and don't breathe the dust of whatever media you're using.

hth


doug

Sun God
10-07-2014, 10:45 AM
Sorry for the delay in replying to my own thread - life got away from me for a bit there.

Thanks for all the replies everyone. Seems that was I was thinking was the case - everyone bases the 16CFM 'standard requirement' for a blasting setup on the premise you're going to be blasting car panels, not trinkets and doodads.

There's a heap of really useful advice here and I'll take it to heart. Looks like I'll be buying the best 2hp shop compressor I can find, and any spare tanks or dead site compressors that come up. I'll try and find a nice gun with a carbide nozzle - I found one on Grainger I think that actually showed the reduction in CFM requirements as you go down in nozzle size - the smaller nozzles actually get well into the realm of your standard shop compressor - 5 or 6 CFM. Which assuming a 50 or 60% consumption cycle is actually quite comfortable.

As an aside, has anyone done any Electroless Nickel plating and cares to share any hot tips?

Paul Alciatore
10-07-2014, 01:28 PM
I did the two tank thing with my small compressor. That second one is a portable tank so I can take it to the job when needed. I have a valve between the tanks so I do not have to use it when it is not necessary. Less strain on the compressor with shorter cycles.

The jury is still out on the long term use of this set-up as I am still setting up my shop.



You could add a second air tank out of the way & by the time you used both tanks the small job would probably be done. I had a 25 gal compressor go bad so I now use the tank to roll to remote places I don't wave enough hose for outside.

michigan doug
10-08-2014, 10:15 AM
"Less strain on the compressor with shorter cycles. "

Just my opinion, but starting is where the real stress and strain on a compressor happens. Half the runs at twice the run length will make your compressor last longer.