Any recommendations on a hardness tester?
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Heat treating kiln
- Thread starter Pevehouse
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- Nov 25, 2015
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I would contact Bartlet and see if they have any manuals about using it as a heat treat oven for that controller. They may have a new overlay or just provide advice. Anyway you go it doesn't hurt to ask and explain.
And yes, that would make a great way to melt (brass, copper, bronze, aluminum, cast iron).
Great buy. you can also cook hot dogs and pizza in that style (horizontal vs vertical)
..
And yes, that would make a great way to melt (brass, copper, bronze, aluminum, cast iron).
Great buy. you can also cook hot dogs and pizza in that style (horizontal vs vertical)
..I have a Grizzly Rockwell-style tester. It seems to work, and it works across a good range of hardnesses... There are "rebound" style testers that are smaller and less expensive. I'm aware of them but really lack the knowledge to say much more than that. If you don't need great precision there are hardness files and awls that will put you in a range.
Sorry I can't be more help, but I'm sure there are some real experts around that could chime in...
GsT
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- Nov 25, 2015
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Last edited:
- Joined
- Nov 25, 2015
- Messages
- 10,038
I didn't know Grizzly had a rockwell tester.
Well, it looks like it's been discontinued, so I guess they don't. https://www.grizzly.com/products/grizzly-hardness-tester/g9645
I suspect most testers of that style are going to be OK as long as they arrive intact. I opted not to try buying a used one because if the guts aren't properly braced and secured for shipping they won't survive transit and most sellers don't seem to know what they have - they're just liquidators.
GsT
- Joined
- May 7, 2023
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I would contact Bartlet and see if they have any manuals about using it as a heat treat oven for that controller. They may have a new overlay or just provide advice. Anyway you go it doesn't hurt to ask and explain.
And yes, that would make a great way to melt (brass, copper, bronze, aluminum, cast iron).
Great buy. you can also cook hot dogs and pizza in that style (horizontal vs vertical)
Great for heating pizza!
900* for 30sec.
Peeve ask away, I heat treat about once a week.
- Joined
- May 7, 2023
- Messages
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This is why we write these things down.
Here’s our heat treat/draw back chart.
Find your steel on the left and follow the corresponding heat treat temp for hardening. Ignore the 20-30 min per inch that’s written there, you want 1hr soak time per inch for heat treat.
For tempering/drawing it back you use the numbers on the right. Higher number you get a softer steel, lower number higher RC#.
For drawing back you again want at least one hour per inch, but longer is OK though too long risks decarburizing the surface.
But that is why you have the surface grinder.
The tempering range and typical hardness numbers on this chart are flipped, never made sense to me why they did this as it makes it rather confusing to understand.
Stainless foil wrap will keep the steel from losing its carbon and is a must for items where surface hardness is critical.
You’re also going to need some fire brick to put your steels on to cool. Even cheap wood stove brick will be ok as long as you keep it bone dry at all times.
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That looks like your kiln is pretty well ready to go. Wouldn't hurt to put a good thermocouple inside and run it, to see how well it displays and holds temps. Having a top end of 2500F would be great, as you'll be able to harden stainless knife steels which can require 2000+ temps. The hardness files is an affordable way to at least get in the ballpark. For more accurate readings, you'll need an indenting style tester like a Wilson( or clone ). For small parts, something like an Ames( which is what I have ). There are a number of relatively cheap rebound type hardness testers on eBay, but they have limitations, like not working on small and/or thin coupons.
