Well, good news...... I found a 1"-40 tap and die to make a plug in the
top of my cylinder. A 1 inch hole isn't exactly what I had in mind, but
it'll have to work for now. I will start with some solid bar stock for
the plug if I can find it..... Chances are I'll have to turn it on the
lathe before the die will accept it.

That's what I'll be doing over lunch today. Probably won't finish
today. I still don't know what pressure this thing will balance out
at..... I couldn't find any information on that. It seems to me the
1200psi would be complete "theoretical" sublimation. I have also
considered, once pressure inside the tank builds, temp should change.
The CO2 will absorb heat? right? I would guess the sublimation rate
will be dependant on the thermal properties of the tank......The tank
will get cold, right?

Um, that's "solid roll stock" - Good grief !

spiral_72 wrote:
Well, good news...... I found a 1"-40 tap and die to make a plug in the
top of my cylinder. A 1 inch hole isn't exactly what I had in mind, but
it'll have to work for now. I will start with some solid bar stock for
the plug if I can find it..... Chances are I'll have to turn it on the
lathe before the die will accept it.

That's what I'll be doing over lunch today. Probably won't finish
today. I still don't know what pressure this thing will balance out
at..... I couldn't find any information on that. It seems to me the
1200psi would be complete "theoretical" sublimation. I have also
considered, once pressure inside the tank builds, temp should change.
The CO2 will absorb heat? right? I would guess the sublimation rate
will be dependant on the thermal properties of the tank......The tank
will get cold, right?

Anything uninsulated that I've ever put dry ice in has gotten quite cold
and had condensation all over the outside. Plan on a damp cylinder.

--
__ Elaine T __
__' http://eethomp.com/fish.html '__

"spiral_72" wrote in message
oups.com...
Well, good news...... I found a 1"-40 tap and die to make a plug in the
top of my cylinder. A 1 inch hole isn't exactly what I had in mind, but
it'll have to work for now. I will start with some solid bar stock for
the plug if I can find it..... Chances are I'll have to turn it on the
lathe before the die will accept it.

That's what I'll be doing over lunch today. Probably won't finish
today. I still don't know what pressure this thing will balance out
at..... I couldn't find any information on that. It seems to me the
1200psi would be complete "theoretical" sublimation. I have also
considered, once pressure inside the tank builds, temp should change.
The CO2 will absorb heat? right? I would guess the sublimation rate
will be dependant on the thermal properties of the tank......The tank
will get cold, right?

I know this is a long shot, but is there any concern about the steel you are
using for your cylinder at the very low temperature dry ice is at? Is
embrittlement or anything else that could weaken the cylinder a concern?

dwhite

Actually, yea..... I thought about that. I really don't know what to
expect. I would suppose a material could be brought to a low enough
temp causing that material to become brittle. Water, plastic, chewing
gum, lots of stuff becomes brittle at a low enough temp. Any idea what
that temp is for steel? Oh, a little note here. The dry ice did not
seem to effect my lunch box. I'm still using the lunch box anyhow :)
pat - pat..........3 hours 30 minutes till eatin' time.

A damp cylinder is the least of my worries. Besides maybe I can collect
it and use the water to refill what evaporates from the tank. HA!

So, many unknowns..... Guess that reaffirms the fact that the
cylinder's first week or two will be spent outside.

"spiral_72" wrote in message
oups.com...
Actually, yea..... I thought about that. I really don't know what to
expect. I would suppose a material could be brought to a low enough
temp causing that material to become brittle. Water, plastic, chewing
gum, lots of stuff becomes brittle at a low enough temp. Any idea what
that temp is for steel?

I haven't looked that up -- maybe it can be found by googling. It probably
depends on the type of steel, although they might all be in the same
neighborhood. I checked on dry ice the other day and I think it sublimes
at -78.5 deg C at atmospheric pressure, and warmer at higher pressure, but
you'd need an equilibrium diagram for that. -78.5 C should be the worst
case though.

dwhite

My odds for this one:

60% chance the whole thing is a hoax. Pretty funny one at that.
25% chance of a fizzing flop due to leaky welds and threads.
14% chance of a new Darwin Award winner
1% chance Spiral will have the last laugh when the whole thing works as
planned.

1 LITTLE PERCENT!!!???!!! WHAT'S UP WITH THAT?

Actually, the ONLY thing I am concerned about is I throw the ice in
this dude....cork it..... have it build up pressure and the CO2 only
lasts five minutes. I have no idea what the equivalent gas volume a 1
pound chunk of dry ice has.

Oh, for those wanting an update...... Hopefully I will be able to cut
threads today over lunch for the tank pressure gauge. I will hopefully
weld the top on it tonight.and hopefully I will have some news, good or
bad, by Monday morning.


1 percent.... good grief.

"spiral_72" wrote in message
oups.com...

1 percent.... good grief.

ROFLMAO....I certainly wish you luck with it, and try not to blow yourself
and family into the next millenium.
--
"In the beginning, God said the four-dimensional divergence of an
antisymmetric,
second rank tensor equals zero, and there was Light , and it was good."