[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]

RE: [T3] Lower HE's


On 10 Dec 2004 at 11:24, Gamboa, Gary wrote:

> >then you can sandblast them and POR20 them
> 
> POR-20? Do they get that hot?

POR-20 is supposed to be good to 1400F, which is astonishing.

The data sheet for POR-15 indicates that it will work up to 600F, which is 
pretty surprising to me, but should be more than enough for the outer sheet 
steel of the HEs.

OTOH, I just checked out Rustoleum's web site and they show a heat resistant 
paint that is good up to 1200F. I'll bet that it's a LOT cheaper than POR-15 
and might even be locally available. It comes in 5 colors, including black, 
white, and silver/grey.

Overall, I'm pretty skeptical about some of these hi-temp claims. A lot depends 
on how they define "resistance." Heating to some temp and then cooling back 
down without visible color change is a lot different from holding it at that 
temp, in air, for an extended period, and then expecting it to still protect 
the surface the same as an unheated sample.

For example, metals start to glow dull red at 1200F and I don't know any 
organic compounds which will survive that. Zinc and cadmium vaporize only 
slightly above that, but generally don't last that long, since they oxidize 
first if this happens in air.

-- 
Jim Adney
jadney@vwtype3.org
Madison, WI 53711-3054
USA

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]