[TheForge] Suggestion for a Test (was: Mineral Wool)

[Jeffrey Polaski]

As I see it, the real issue is how well our forges heat metal, so I'd
like to propose to the group test for our forges. It's cheap and easy,
and can help us all talk more clearly. I propose that we take a 1" x 1"
x 6" piece of bar stock and measure how long it takes to get up to a
certain temperature, as measured by a Tempilstick.

Once the temperature is decided, here's what I'd like to know:
	How much gas is used per hour
	How long the forge has been running
	How long the bar took to get to heat
	*Maybe* cubic inches of volume
	*Optionally* how the forge is actually made

These are all measurements that can be made with cheap and easily
available stuff. Beyond the forge, a timer, tape measure, bathroom scale
(for pounds of propane), and Tempilstick are all that is required.  The
Tempilstick can be found at local welding stores, or on the internet so
it's not exotic or anything.

I'm not sure what the best temperature would be, but I'd guess that
2,500 degrees F would be about right. The max temperature for propane in
air is  3595 degrees F, so we might want to make the test temp higher --
I'm not sure what my forge runs at and 2,500 is just a guess. 

As I see it, the real issue is how well our forges heat metal, not how
well it reflects heat off the walls, how much air flows through or
exactly what it's made from. Those are all *parts* of making a
good-running forge, but discovering when and where and how they are
relevant for all forges is non-trivial. Having a standard test will let
us talk objectively and make meaningful comparisons, both between
different forges *and* with the same forge after modifications.

So, with that said, please let me know if you have any comments.


Jeff Polaski

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net] On Behalf Of Jerry Frost
Sent: Friday, May 25, 2007 7:27 PM
To: Sponsored by ABANA
Subject: Re: [TheForge] Mineral Wool

This topic has been coming up for as long as I've been 
on the list and for the reasons you give it's virtually 
imossible to make a meaningful determination.

There is however one meaningful test a person can do 
and that's measure their forge before and after 
applying an IR reflective coating. Unfortunately that's 
only going to tell you what happened in one furnace. 
Maybe if enough people did it and recorded the results 
in a central file we could develop a range of 
expectations.

Till then we have only the manufacturers data and 
anecdotal evidence. The anecdotal is impressive enough 
to make using an IR reflector regardless of furnace 
liner type a no brainer though.

Frosty
-------------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.

http://www.artmetalradio.com/


From: "Kathy" <keporter at comcast.net>
> Jerry,
> The problem does not come in measuring internal 
> temperatures, but in comparing
> apples and oranges. The temperature in one forge, no 
> matter how scientifically
> gathered, simply won't apply in the next man's forge.


<snip>