Wish I had one. Two grand for the one I want but I'm serious about trying to
make one from scavanged parts. See what happens. I paid attention to the
part about higher carbon/lower temps. The most drastic example for me was
that I started playing with that Pandrol stuff right off the bat and non
magnetic is pretty much orange heat with that stuff. Then one day I had
some of that straight carbon creeper or whatchamacallit material and
discovered it was already non magnetic and was still a dull red (in shaded
This is bad... I knew the chart you were talking about as soon as I read
your comment. ;)
If you're building from scratch, spend the money on the controller and the
matching thermocouple. That's the heart of it, the rest is just brick and a hot
wire. IIRC, I got a 2500 F controller for about $425 and the thermocouple was
part of the kit. Not the "build a helicopter for $25" but still reachable by
the hobbyist. You get what you pay for, heat treatment makes or breaks a blade.
High tech where it counts.
Actually what I had in mind was just a tempering rig made from modified
toaster oven parts... I like your idea though. should be pretty simple to
build the box and wiring and add a commercial controller...
You don't need anything fancy for tempering unless you are working
with D2 or HSS and want to take advantage of their secondary
hardness hump. (~900F)
The lack of a temperature controlled oven is what's holding me back
from using A2. Yes I could "stick it in the fire" but to get A2's
full potential a guy needs to "go by the numbers". :/
Very un-blacksmith like I know, but A2 won't be any better than
52100 without it, so why bother?
One of the guys on r.c.m (metalworking) claimed to control his by
hand using a thermocouple and meter, did that for years before
getting a good-used controller cheap enough. The price came down
on them. :)
That's my plan for A2 and some VascoWear I already have.
I'm not going to use the electric-rig that many times that I can't
do it by hand. :) I already have a meter with the resitor on it and
face that reads too 1400C.
On the face in tiny letters it sez-
Thermocouple Pt/Pt13%Rh, Ext.Res.10ohms, SPI Instuments Co.
Got it used for $2 at an industrial-type second-hand-store. ;)
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