Clarke sandblaster gun - moisture?

I came upon a Clarke sandblaster gun, filled it with abrasive, ran the
pressure up to 100 PSI and tried it out. this is a syphon type blaster
that looks a bit like a paint sprayer.

I know when spraying paint folks advise you to have something in the
line to dry the air. Is a dryer necessary if I'm spraying abrasive?

Has anyone had results they were please with using a sandblaster gun?
- Mike

On Aug 7, 2:39*pm, Michael Horowitz wrote:
I came upon a Clarke sandblaster gun, filled it with abrasive, ran the
pressure up to 100 PSI and tried it out. this is a syphon type blaster
that looks a bit like a paint sprayer.

I know when spraying paint folks advise you to have something in the
line to dry the air. Is a dryer necessary if I'm spraying abrasive?

Has anyone had results they were please with using a sandblaster gun?
- Mike

What part of the world are ya in ??? Florida or some tropical place
with the relative humidity that's close to taking a shower then I
would install a dryer in the airline. If you are in Arizona, with 110f
air and 4 % humidty then the part will never rust/corrode.. G

Ben......

Michael Horowitz wrote:
I came upon a Clarke sandblaster gun, filled it with abrasive, ran the
pressure up to 100 PSI and tried it out. this is a syphon type blaster
that looks a bit like a paint sprayer.

I know when spraying paint folks advise you to have something in the
line to dry the air. Is a dryer necessary if I'm spraying abrasive?

Has anyone had results they were please with using a sandblaster gun?
- Mike

From my past experiences in NE Ohio and Western PA, in the summer, with
both siphon guns and pressure systems for abrasive blasting, you need
good moisture traps and perfectly dry air. They will plug with damp
abrasive. I have owned various models of both types of systems and
currently use a pressurized tank blaster.

What I do is have a small dryer with a male and female quick disconnect that
I snap in line ahead of the gun when painting or using a sandblaster. You
can pick these up for less than $10 at Princess Auto( Canadian version of
Harbor Freight)
Nothing worse than just about finishing a great paint job and have a drop of
condensation sprayed over it!
When sandblasting one drop of water can get the sand clogged or put little
rust spots on bare steel. Disconnect the dryer and keep it in a plastic bag
so it won't soak up moisture from the surrounding air when not in use..
Bob

"stol" wrote in message
...
On Aug 7, 2:39 pm, Michael Horowitz wrote:
I came upon a Clarke sandblaster gun, filled it with abrasive, ran the
pressure up to 100 PSI and tried it out. this is a syphon type blaster
that looks a bit like a paint sprayer.

I know when spraying paint folks advise you to have something in the
line to dry the air. Is a dryer necessary if I'm spraying abrasive?

Has anyone had results they were please with using a sandblaster gun?
- Mike

What part of the world are ya in ??? Florida or some tropical place
with the relative humidity that's close to taking a shower then I
would install a dryer in the airline. If you are in Arizona, with 110f
air and 4 % humidty then the part will never rust/corrode.. G

Ben......

Michael Horowitz wrote:

I know when spraying paint folks advise you to have something in the
line to dry the air. Is a dryer necessary if I'm spraying abrasive?



Yes.

Get the big, all-metal jobber from HF. It has a drain for any trapped
water. Set you back $20 or so, but I have it bolted to the side of my
compressor cart. The instances where you want water droplets in your
compressed air are few and very far between.

"Ernest Christley" wrote

Get the big, all-metal jobber from HF. It has a drain for any trapped
water. Set you back $20 or so, but I have it bolted to the side of my
compressor cart. The instances where you want water droplets in your
compressed air are few and very far between.

To the OP:

I made a homebuilt water trap, that seems to get the lion's share of the
water and moisture out of the air before it can get to any desiccant type
air dryer. Beware that a small desiccant will be wet and change color and
be used up very quickly at the high airflow that sandblasting requires.

Get a 6 foot length of 1-1/2" steel pipe, (or bigger, and bigger could only
work better) and an assortment of fittings, to adapt it to a configuration
like the following. You want to pipe your air supply into the bottom of the
pipe, which will be used straight up and down. You will want to put the air
into the pipe with a T fitting, so the air will be going into the T and
traveling upwards, but a few inches lower than the T will be a reservoir
area of a few inches of pipe and a drain petcock to remove accumulated
water. I also put a quick disconnect on the inlet and the outlet to make it
handy to hook up.

After the air enters, it will travel upwards, but pretty slowly which will
tend to let water drop out of suspension. Because it is in a big piece of
steel, the air will also cool and condense and let more water drop out, and
run down the pipe to be collected and drained out the petcock at the bottom.
--
Jim in NC

Plumbing your shop or hangar for compressed air is money well spent.
Use iron pipe, the size selected according to the run & volume. This
should be defined by your local building codes.

All runs should slope TOWARD the compressor. That is,any water would
have to run UPHILL to find an outlet.

Do not use copper nor plastic.

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Blasting media is also subject to contamination by moisture. It
should be stored in air-tight containers. In the worse-case situation
it may need to be dried before it can be used, a hell of a mess
involving an oven and trays. For small parts you may wish to consider
tumbling rather than blasting.

-R.S.Hoover

wrote in message
...
Plumbing your shop or hangar for compressed air is money well spent.
Use iron pipe, the size selected according to the run & volume. This
should be defined by your local building codes.

All runs should slope TOWARD the compressor. That is,any water would
have to run UPHILL to find an outlet.

Yep, agree, completely. In my case, I need to be portable, so my iron pipe
cool-down trap is a good compromise.

Another point worth mentioning. If your shop air plumbing is overhead, and
it drops down to an outlet, don't use an elbow to turn out the line. It
will funnel any water condensed in the down-line, right into your air hose.
Instead use a T with a length of pipe below the outlet fitting, or even
better, make the air line do a U-turn, then come back up to the outlet, with
a drain at the low point.
--
Jim in NC

On Thu, 07 Aug 2008 16:39:51 -0400, Michael Horowitz
wrote:

I came upon a Clarke sandblaster gun, filled it with abrasive, ran the
pressure up to 100 PSI and tried it out. this is a syphon type blaster
that looks a bit like a paint sprayer.

I know when spraying paint folks advise you to have something in the
line to dry the air. Is a dryer necessary if I'm spraying abrasive?

Has anyone had results they were please with using a sandblaster gun?
- Mike


I spent weeks and weeks and weeks bead blasting my Auster Fuselage.
most of the time is spent waiting for the compresser(s) to pump up.
3 compressers Tee'd together work almost manageably to give near
continuous air. if you are doing it this way a good trick is to alter
the control valves so that they kick in at different pressures. just
by listening you can tell what pressure you have.

a better source is a trailer mounted diesel compressor, the type you
hire. these deliver full pressure on a continuous basis. I suggested
this to one of my mates. the bugger bead blasted an entire fuselage in
1 day.

moisture you will see as a dark spot in the centre of the bead spray
on the tube you are beading off. if you get the dreaded dark spot then
you should try the combined water traps pressure reducers in the line.
some people use 2 or three of them, placing them between line
sections. the dark spot is caused by condensation and will often
develop corrosion overnight.


you will need to replace nozzles on a regular basis. I machined
myself up nozzles in nylon that worked as well as the original ones.
you can tell when they need replacing because the internal passage
wears out oval and you lose the volume of beads you need.

you are wearing protective gear right?
a good timesaver is to cover the faceplate with some thin transparent
plastic. this will fog up gradually as the bounced beads abrade it.
you just tear off the transparent plastic and replace it. saves
stuffing up the mask's actual faceplate.

be sure to wear breathing protection.

Stealth Pilot

On Aug 10, 5:56 am, Stealth Pilot
wrote:

I spent weeks and weeks and weeks bead blasting my Auster Fuselage.
most of the time is spent waiting for the compresser(s) to pump up.
3 compressers Tee'd together work almost manageably to give near
continuous air.
------------------------------------------------------------------------

One way to tell a good Chapter from the other kind is that they're
always involved in projects developing equipment that would be too
expensive for an individual to managed on his own, such as pigs of
lead accurately marked as to their weight, or the scales and stands
needed to do your W&B. A portable compressor capable of driving at
least one sand-blasting gun is another example, especially when folks
find out they can have the thing virtually for free.

Herez How:

You start with an old VW engine, and I'm talking basket-case. Patch
it up so that cylinders 1 & 3 will run. Remove the rockers for
cylinders 2 & 4. Put a wipe of Permatex on the intake valves for 2 &
4 and install the stock spring & keeper. On the exhaust valves for 2
& 4 you want a very light spring, somehting having only a few OUNCES
of compression.

The exhaust ports for cylinders 2 & 4 become your air INLETS. The
sparking plug hole for those jugs becomes you OUTLETS (and are fitted
wtih a check-valve, which you can make from an old spark plug and a
ball-bearing.)

Back in the days of the Model T this arrangement was the most common
means of providing compressed air for jack-hammers and the like.

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a good timesaver is to cover the faceplate with some thin transparent
plastic.
------------------------------------------------------------------------------

Here in the States we use plastic wrap (brand name: Saran Wrap, et
al). You put four or five layers on the face-plate with one edge
aliigned, the other overlapping by aboout an inch. As it fogs up, you
simply peel off the top layer, keep on working.

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be sure to wear breathing protection.
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Roger that! Media-blasting has to be the worst job in the world.

-R.S.Hoover