Forging at altitude

J

Jack Henry

Joined
May 15, 2015
Messages
43
So I live at 7200 feet and recently I heard that forging at altitude causes your price to cool faste. I get about 45 seconds of hammering out of a 1/4" bar before I have to put it back. I would think high elevation would make the heats last longer but I guess not. Does anyone know if this is true or more importantly why it happens.
 
I was once told ya couldn't weld if barometric pressure wasn't atleast 29 the only thing is it only reaches that in fl. if big storm is seeting of coast. after waiting for that magic # that only show a few times a year I tried with it below and I know longer care what it is it all works for me.

also I put my money on bill Burke answer
 
Last edited:
Unless you are forging in an extreme wind environment, most of the heat lost is via radiation. "Still Air" or "mildly blowing air" is only around 1/6 as strong until your temperature drops to around 400 C.

By extreme wind, I mean at a minimum 50 m/s (110 mph) before you have any noticeable effect.
 
I was once told by a fellow that steel heated in a coal forge stayed hot much longer than the same piece of steel heated in a gas forge. I called bullshit on that too.

Another one was that you couldn't forge weld in a venturi forge above four thousand feet. Mike Vagnino. Bob Kramer and myself successfully welded two bars of 1084 together at government camp Mount Hood Oregon, with no flux at all at an altitude of 8400 ft. in a Dave Lisch venturi forge.
 
I'm at 7500 feet and don't notice but I have no point of reference having only forged here.

You might have to burn more fuel to get there... I know my vehicles all run way better at sea level. But hot is hot!

As far as bending clips goes I do think my hand held propane torch might not get as hot, when I use my clip bender (big heat sink) I have to use an acetylene jewelers torch! It's probably just something I am doing but I have seen lots of videos heating Ti and my torches do take longer. It's probably just me... I can solder sterling silver with absolutely no issues.
 
Technical, the thinner air cools the blade slower, because there are less atoms per unit of air to absorb heat. This is not significant, and probably isn't even measurable.

The only thing affected is that there is less oxygen available to burn, because the air is thinner.

This makes a venturi burner run less efficient. You have to push more gas to draw more air, but the resulting flame is rich, so it is slightly cooler. A blown burner need more air to get hot, but the larger flow volume makes for greater dragon's breath, and thus wasted=s a bit of the fuel by burning it outside the chamber.
 
I wonder if some of these myths are sort of extrapolations from water boiling temperatures and altitude. Not that it makes them any better. Like 212 degrees at sea level and 199 degrees at 7200 feet. But maybe the myths you guys are mentioning are related to people's half baked knowledge of something else.
 
I only notice my coffee tastes different when I work at high altitude.
My steel & anvil dont care.
 
When I lived in New Mexico at 10,500 ft moving from South Carolina right at the coast, I did't notice anything different other than I got winded walking long distances for the first couple of weeks, and when the wind blew it actually felt cool as it wasn't 99% humidity like it almost always is here in SC. Oh, and sometimes when I was in NM it would rain really hard but never reach the ground, that was odd.
 
Also, shade actually WORKS when it is 95f in New Mexico unlike SC when it is 95 with 99% humidity. ;)
pleasanthill said:
When I lived in New Mexico at 10,500 ft moving from South Carolina right at the coast, I did't notice anything different other than I got winded walking long distances for the first couple of weeks, and when the wind blew it actually felt cool as it wasn't 99% humidity like it almost always is here in SC. Oh, and sometimes when I was in NM it would rain really hard but never reach the ground, that was odd.
Click to expand...
 
You must log in or register to reply here.
Back
Top