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Re: New Shop Questions

J.D,

I would agree with Tom on engineering of gas/air piping.  I too use 
natural gas, though a shop here in town uses propane and it works superbly.

I have set up probably 4-5 shops, and for me (as Tom) silencing the blower
is very important.  I build a small "doghouse" for my unit, which is a
Gast Regenerative blower, and put it either on the roof or outside the
building completely.  Nothing can make glasswork more unenjoyable than a
constant loud roar.  In my shop you can _barely_ hear a gentle hiss from
the burner tips - that's it.  Silence the hell out of it, and you won't
ever regret it. 

I use 3/4 black pipe with ball valves for the gas.  Like Tom, I just open
them and my fires are ready to go.  I use 2" PVC for the air.  I have two
sets of fires, and all works very nicely with these sizes.  I use that
latex gum-rubber tubing to connect the actual fires, but I don't feel good
about that stuff, and will probably put steel flex hoses there soon.  The
hand torch, is another situation of course. 

A pressure regulator is a must, and you can build one.  I ordered a $100
Fuji regulator from Grainger, and was shocked to find out it was just a
piece of 1 1/2" pipe with a ground washer and a spring!  I gave it back,
and built a much better one, based on a design I'd seen before.  All you
need are two pieces of pipe or tubing that fit rather precisely (one
inside the other). 

Both tubes should be about 4 inches long.  Mine are approx 1 1/4" dia. 
Put a cap or plug on the top end of the larger one.  Cut some large
notches in the smaller one about 1 inch from the bottom.  Like this: 
        ______
	|    |
	||  ||
	||  ||
	||  ||
	||  ||    <  large notches (holes) in small pipe
	|    |
      ==||  ||==  <  ridge to support washers
	 |  |
	 |  |
	
      to air plumbing

In operation, the pressure raises ("floats") the outer pipe up and the
excess air escapes out the notches in the small pipe.  I have a small
ridge on the bottom of the larger pipe to support washers or other
weights.  More weights = more pressure.  This unit performs (IMO) much
better than the spring or diaphram type regulators.  It seems to quickly
dampen minor surges and drops. 

One final note:  all blowers heat the air they are compressing.  The
exhaust from the pressure regulator will be very warm, and it is a good
idea NOT to place it cooped up inside an insulated (sound proofed) box
with the motor.  Likewise, it's a good idea to place the blower's intake
outside the enclosure as well, preferably from outside.  This is also a
health issue:  if the blower is drawing its air from inside your shop
(where others are painting and using solvents) your blower is taking these
toxic fumes, burning them into even more toxic stuff, and delivering it
right to your face! 

I'm particularly sensitive to this, because I worked in a shop several
years ago where I was getting SICK after extended periods of glasswork. 
To make a long story short, we isolated the problem to what I just
described. 

         -John Anderson
References: