The Sandblasting / Air Eraser / Etching thread

[u18b]

OK Chris.  You have my curiosity.

I have a little small air brushing compressor- not a garage compressor.



So if I was going to attempt a mod.... it would need to be a small radiator of some kind.

So how about a heater core?
Here is an ebay search:
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=heater+core+-seal+-ring+-hose+-rings+-clamp+-clip+-sensor+-tube+-tubes+-vaico+-gasket+-valve&_sacat=6030&LH_TitleDesc=0&_sop=15&_osacat=6030&_odkw=heater+core+-seal+-ring+-hose+-rings+-clamp+-clip+-sensor+-tube+-tubes+-vaico+-gasket&LH_ItemCondition=3

Looks like a new one can be had for maybe 20 bucks or so.  We would want a new one that doesn't have crud in it.

So..... what kind of pressure can a heater core take?  Can it hit 65 psi?

[Chris333]

It's about 3' long, but there isn't much water in it. If you look at some of the Youtube videos they claim to "never have to drain your tank". Some people just zig zag a pipe up and down a wall to cool the air down.

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This is a radiator out of a Chevy:

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I have another small compressor in the basement for air brushing. I have no traps at all on it and haven't seen water come out of it. Perhaps because my basement is cool. This is my basement compressor:
https://www.menards.com/main/tools/air-compressors/performax-reg-8-gallon-150-psi-portable-electric-horizontal-air-compressor/300811/p-1444423541383-c-12910.htm
It's line from the pump to the tank is about 3/4" dia with aluminium fins on it. Same type at HF:
https://www.harborfreight.com/8-gallon-15-hp-150-psi-oil-free-portable-air-compressor-64294.html

The one in the garage probably gets water because of the heat like Pete said.


For a smaller compressor you could get something like this:
https://speedmaster79.com/Flat-Transmission-Oil-Cooler-15.5-x-7.5-Electric-Thermo-Fan-Kit
Wire up the fan to the pressure switch so it comes on when the pump does.

[Chris333]

Pete, I drained the pipe in blue. The tank has a drain on the floor and there might be a little water in there as well. But I haven't got water out of the hose since installing the radiator.

Ron, There should be a check valve between the pump and the tank so I'm not sure you need a high PSI radiator.

[u18b]

Apparently not much for a heater core.

This site says they are rated at only about 10 psi.

https://www.yourmechanic.com/article/how-to-flush-out-your-heater-core-by-spencer-cates

[u18b]

OK... I see, you are correct.

An oil cooler can be rated as high as 150 psi.   That's the way to go.

https://www.google.com/search?safe=active&source=hp&ei=x79VX_7SMszUsAX3or2oAw&q=oil+cooler+pressure+rating&oq=oil+cooler+pressure+&gs_lcp=CgZwc3ktYWIQARgDMgIIADICCAAyAggAMgIIADIGCAAQFhAeMgYIABAWEB4yBggAEBYQHjIGCAAQFhAeMgYIABAWEB4yBggAEBYQHjoOCC4QsQMQxwEQowIQkwI6DgguELEDEMcBEKMCEIsDOgUIABCLAzoLCAAQsQMQgwEQiwM6BQgAELEDOggILhDHARCjAjoFCAAQkgM6BQguELEDOggILhDHARCvAToCCC5Q5whYjS9gr0ZoAHAAeACAAdMBiAHRFJIBBjAuMTkuMZgBAKABAaoBB2d3cy13aXq4AQI&sclient=psy-ab

[peteski]

Apparently not much for a heater core.

This site says they are rated at only about 10 psi.

https://www.yourmechanic.com/article/how-to-flush-out-your-heater-core-by-spencer-cates

That is correct, car cooling systems don't develop high pressures.  The radiator caps are the safety valves for the cooling systems, and in the older cars had their pressure rating embossed on them.  10 psi sounds about right.

You are dealing with pressures in excess of 100 psi. You need a radiator that will be able to withstand those pressures.  Air conditioning systems operate on pressures of few hundred of psi. the evaporator or a condenser from the air conditioning system would be more appropriate.

EDIT: or the oil cooler that Chris recommended. 

[Chris333]

On youtube there are all sorts of ideas. I used what I did because it was free from work. Maybe it's size was overkill, but it worked. I was originally looking at a huge trap, but read people still got some water. Them someone told me to get a transmission cooler and put a fan on it. From there I found a million ways to skin a cat.

[Chris333]

I tried to use the radiator from my Volkswagen...   

[Chris333]

Here is the exact place I learned about the pre-cooler:
https://www.thesamba.com/vw/forum/viewtopic.php?t=686113&highlight=

[Teditor]

The purpose of this thread to is pool information in the way that makes The Railwire the great place it is.

A brilliant presentation, I have a Passche unit and have yet to get it to operate proficiently, after reading your posts, I can already see some areas I need to address, you have put in a lot of time and effort, I for one really do appreciate your efforts.
Ted (Teditor) Freeman
From the Land Down Under.

[craigolio1]

The small bottle on the right came with the air eraser.  A bottle like that came with my Paasche too.
But that is nothing.

The bottle on the left is a 2 pound bottle and I use almost a whole bottle when I do an EP-2.

Which is also a reason for me to go with a sandblasting booth.
In the past, all that Al-Ox went into the yard.

But with a sandblasting booth, I should be able to reuse it a little- assuming what I'm blasting is pretty clean.
For example, I always get all the paint I can off of brass before I blast it. 

But if I blasted the paint off, then the excess Al-Ox would be contaminated with paint particles and chips and clog the system next time around.

I have the same size container if Al-Ox for my Badger sand blaster. I have reused it many times even though it’s contaminated. When I run through the supply I sift it using using a baby wipe container with a tight fitting screw on lid. The lid has been cut out and a piece of hash pipe screen fitted into the lid. I tape the contraption to a sawzall blade and run my recip-saw at a low speed. This acts as a shaker and I can sift the whole container in about 15 min.

Craig

[u18b]

So....  Here is a diagram of the air flow in a typical air brushing set-up - with a tank (mine).



Everywhere the air has a chance to expand, water can condense.  And there are three places just right here- and actually, there's an extra one in the airbrush itself internals.

Overall, a lot of water condenses in the tank itself.  Water is supposed to be emptied from the bottom every time or the tank will rust.

And then.... if I were to pursue Chris' suggestion, I would build something like this (below) with an oil cooler.
Would need:
oil cooler (about 20-30 bucks)
some kind of water trap  (20 bucks)
fittings (10-20 bucks)



The idea would be to remove some water/moisture BEFORE the air gets to the tank.

[u18b]

So here would be the question.

Adding an air dryer would:
-- reduce water in the main tank
-- cost about 50-70 bucks.

-- Could add noise.  The whole set-up rattles so would need to build a way to reduce noise.
-- will make the whole set-up LESS portable (I move mine inside and outside).

But maybe another possibility would be to add one or two MORE water traps simply connected to the the one I already have.

plus:
-- cost less

possible negatives:
-- water still in main tank
-- 2 or 3 water traps will stick out much farther.  Will it be stable?  Will it get bumped and damaged?
-- Will I get constant pressure at the air brush/sandblaster or will the I get pressure drops (set at 60 psi, push button starts out at 60 psi, but then drops to 40 psi within a second or two.

[garethashenden]

If you do add more water traps I'd be inclined to move the pressure valve, or add another one. Then you could regulate it after if goes through the traps, which is what actually matters. Turn up the one on the tank, then use the down stream regulator to set the pressure at the airbrush.

[u18b]

If you do add more water traps I'd be inclined to move the pressure valve, or add another one. Then you could regulate it after if goes through the traps, which is what actually matters. Turn up the one on the tank, then use the down stream regulator to set the pressure at the airbrush.

Yes, that's a good idea.  I had already thought that there are two kinds of traps- those without a regulator and those without.

If I add two, then the stock regulator could be wide open... and then the LAST one would need a regulator to actually control the exit pressure- as you suggest.