[TheForge] Re: Sand blaster problem: hose blows off

[Mike Spencer]

Ries wrote:

ries> I have a sandblaster and the hose just is a slip fit, and it
ries> never comes off- but mine is a siphon- so the air hose is a pipe
ries> thread, and the sand hose has no pressure to speak of.

So how does that work?  No pressure in the sand hose sounds good.

> Sounds like yours is some other variety, which tries to do
> everything with one hose?

   + Tank, maybe 10 gal, bowl bottom, on end, on wheels. Sand goes in
     the tank.

   + Valve #1 pressurizes the tank, seals the fill port.

   + Tee under the tank; stem of tee connects to bottom of tank via ball
     valve #3. 

   + Air delivered to one arm of tee via ball valve #2.

   + Blast hose connects to other arm of tee.

Open valve #1 to pressurize the tank.  Open valve #2 to pressurize the
blast hose.  Open valve #3 (maybe only partly to restrict sand flow).
Stem and one arm of tee are at the same pressure but the flow from the
arm does the Bernoulli thing and sucks the sand into the blast hose.

So how does the siphon deal work?  I'm not married to this gadget,
open for good ideas, safety, simplicity, ease of use etc.

Dan wrote:

dan> Try cutting off 100 or so mm to get a good section of hose. The
dan> inner side of the hose should be a force fit on the barbs.  Use a
dan> screw type hose clamp and tighten until you see a slight
dan> distortion in the rubber as in it is starting to come through the
dan> slots. I have has to do this to my hf sand blaster to keep the
dan> hose on.

Huh. I'd have thought the wire clamp would be better, more localized
squidge (technical term :-) into the nipple barbs.  Maybe not.

I'll try that if getting some kind of threaded fittings put on the
hose turns into a giant PITA.

ries> TP is the place to get cheap sandblaster parts and pieces. But
ries> you gotta use that newfangled thing- the internet, and have it
ries> delivered.

I was probably the first blacksmith on the internet but I don't do
on-line shopping. [1] 

ries> Or just try to find Canadian equivalents- but if Nova Scotia is
ries> anything like where I live, NOBODY stocks anything locally
ries> anymore.

In my nearby market town, not only don't they stock it, they've never
heard of it. :-) In Halifax there's a huge industrial park and a lot
of stuff in stock.  But it's an onerous, not to say tedious and
tiring, task to find the niche biz that does, in fact, have what you
need. E.g. I'a assured that somebody has stickum-backed abrasive disks
for my old disk/belt sander.  I'll be shpxrq if I can find them, eben
with directions.


I'll try the local big-truck place first.  Maybe they can fix me up
with high-pressure threaded fittings and I can modify the
(nonstandard) tee-widget to match.  The gun [2] already has a threaded
port.  Princess Auto (Canadian version of Harbor Freight) after that.
They fixed me up with a custom hydraulic hose to connect my
(vibrating) air compressor to a (very stationary) tank.



Tnx,
- Mike

[1] Never say never. :-)

[2] Gun? Actually, a very clumsy nozzle affair.  A gun with a trigger
    would be much nicer.  I should look into that after you explain
    how "siphon" works.

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^