Tempering

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tornitore45
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Tempering

Post by tornitore45 » Fri Dec 14, 2018 5:41 am

What happens when one forget the part to be tempered in the oven (420F) for a couple hours?
Asking for a friend.
Mauro Gaetano
in Austin TX

Magicniner
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Re: Tempering

Post by Magicniner » Fri Dec 14, 2018 7:52 am

Should be fine unless the data sheet for the material states a maximum tempering time.

ChipMaker4130
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Re: Tempering

Post by ChipMaker4130 » Fri Dec 14, 2018 10:34 am

Magicniner wrote:
Fri Dec 14, 2018 7:52 am
Should be fine unless the data sheet for the material states a maximum tempering time.
This is my understanding as well. Normally its the temperature that's important, not the time (except that the time must be long enough).

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tornitore45
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Re: Tempering

Post by tornitore45 » Fri Dec 14, 2018 12:06 pm

Thanks. The part, a square drive for sockets, is still file hard.
Mauro Gaetano
in Austin TX

Magicniner
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Re: Tempering

Post by Magicniner » Fri Dec 14, 2018 3:43 pm

tornitore45 wrote:
Fri Dec 14, 2018 12:06 pm
Thanks. The part, a square drive for sockets, is still file hard.
That sounds more like the temperature wasn't correct if that's not the hardness you wanted.

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tornitore45
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Re: Tempering

Post by tornitore45 » Fri Dec 14, 2018 6:22 pm

No. I was afraid to have drawn to much hardness due to prolonged heating. I want it to be at blue color temper, hard but not tool hard.
Mauro Gaetano
in Austin TX

ChipMaker4130
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Re: Tempering

Post by ChipMaker4130 » Fri Dec 14, 2018 9:32 pm

Tempering temps depend on the material itself, and will vary by several hundred degrees for the same hardness in different materials. 420 is pretty low for a lot of them.

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NP317
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Re: Tempering

Post by NP317 » Sat Dec 15, 2018 12:58 am

Search Amazon for:
Tempilstik sets

Multiple temperature sticks are available.
I assume there are other brands of similar (possibly better?) products.
~RN

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tornitore45
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Re: Tempering

Post by tornitore45 » Sat Dec 15, 2018 6:41 am

Major screw up on my part. I wanted a blue temper like springs, my toaster oven go as high as 550F and I will settle for that.
I set the temperature to 420F based on faulty memory.
No wonder the part (O1 drill rod) was still file hard.
Will retemper at 550F and set a timer so I do not forget. Wife is not trilled with the use of the toaster oven, you know how possessive they get about the kitchen, even if there is no issue heating a piece of clean steel instead of a croissant.
Mauro Gaetano
in Austin TX

Downwindtracker2
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Re: Tempering

Post by Downwindtracker2 » Sun Dec 16, 2018 12:26 pm

First there is a piece of clean steel, then you never know where it will end. I think a thrift store might have good deal on a toaster oven.
A man of foolish pursuits, '91 BusyBee DF1224g lathe,'01 Advance RF-45 mill/drill,'68 Delta Toolmaker surface grinder,Miller250 mig,'83 8" Baldor grinder, plus sawdustmakers

johnfreese
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Re: Tempering

Post by johnfreese » Mon Dec 17, 2018 10:20 pm

If you know what hardness you want to achieve you can look up the temperature/hardness chart for the steel you are using.

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