Using a minor for boro

[Dog Squeez]

Going to give a demo on Wed. at the Southern Flames (ISGB group in Atlanta). On making borosilicate blown beads, I will be using a minor since that is the
torch most of them have. I work with a Mirage or a HA 40, so I don't know
what pressures to use for a minor. Any suggestions would be greatly
appreated.

Thanks,
Brian

[Greymatter Glass]

try 40 on oxy and 3-5 on LP, adjust from there

If you need to push a really big flame (I doubt it) then 60/8-10 might work a bit better

fwiw: LP burns "neutral" at around 1:9 by volume. So for every 1 cubic foot of LP, you want 9cu.ft. of O2. LP expands more than O2 however, so a pressure ratio is rather diffucult to calculate... if you have flow meters, then set it up for 1:9 and the pressures wont matter.

-Doug

[Dog Squeez]

Thanks Doug,

I had set it at 8 pro - 35 oxy. when I increased O2 at torch flame got turbulant

Brian

[Satori]

Whoah! I had a minor for a while before I got my red max and I had the gas at 5 and the oxy at 15 and was very happy with the way it performed for it's size. 40 oxy just seems ridiculous for such a small torch. To each his own though, ofcourse :)

[ArtGlassHouse]

15-20 psi on the o2, 5 on the propane. Over 20 PSI going through a minor will cool the flame, cutting it's performance in half! LP to O2 ratios are fine, but the speed of flow, diameter of flame all effect the combustion rate.

[Mike_Aurelius]

I routinely teach boro on a Minor and we use 5 PSI propane, 20 PSI oxygen. The needle valves on the Minor are not as good as, say, a Beth or even a GTT, and using too much PSI will really screw up the adjustments - a tiny twist on the valve will result in a huge change in the flame.

It's better to keep your pressures low and leave it at that. Remember the Minor is not designed for very large flames - it has a relatively small heat shield.

[ericsgreen]

I thought the southern flames was a group, is it a location too...

Where is the demo at?

[Greymatter Glass]

ok, I stand corrected. 5/20 sounds good then?

[rustyglass]

Anyone want to buy a minor? I have one with only 6 months on it. great beginner or bead torch.

Rusty

[Dog Squeez]

Thanks, for all the responses, I'll kick it down to 5/20 and increase my patience

Eric, Southern flames is a group (ISGB), meeting is tonight (Wed.7/20/05) 7:pm,
at Beads By Design in Marietta, GA.

Brian

[Blowfish]

How much are you charging for the minor? I need a second one in my studio. Where are you located? I'm up here in BC canada.

[NUBBLET]

I always liked running at 17-25 oxy and 5-10 pro , I really liked it at 20 oxy and 7 pro .