Induction forge tonight?

Metal Shop
#1

Is there a member who can give me the run down on using the induction forge tonight?

I have an old old file I want to heat up and air cool to soften for making a knife and that would be the easiest and quickest way.

Thanks!

Raymond

#2

I may possibly be around, what time are you trying to be there?

#3

About 6:30p

#4

The induction forge is a pretty intensive training and includes the KMG grinder. I don’t know if I can be there tonight, kind of a game time decision. But regardless, this is a pretty long training for a pick up session. There is a class scheduled for next Tuesday though. (for a better option, see below)

As far as annealing your file goes, it is totally doable on the induction forge, but the small gas forge will be easier and better for that operation. Effective annealing requires that the whole piece be brought to a non-magnetic temperature and (preferably) held there for several minutes. Then cooled very slowly. For something like a file, it’s usually ok to allow it to cool on top of a running gas forge, but vermiculite is even better. (the gas forge is about a 10 minute training session)

I can run you through how to do that with the gas forge on Tuesday after class if you want, possibly tonight if I make it up there.

#5

Thanks @yashsedai for the offer and @brsims for the class info.

I’ll hold off for tonight and take the class next Tuesday. :slight_smile:

I just got my 1 x 44" belt grinder running last night - new washers were put on the motor mount bolts, installed a new drive belt, cleaned/lubed the idler, aligned the top wheel, and realigned the platform. New belts are on the way for it in 60, 120, 220, and 400 grit.

#6

Cool.

And more characters.

#7

FWIW, I agree with Brad that the induction forge is not the best way to anneal the file:getting a long, even heat is hard, and cool down is too quick.

I would heat the file in the gas forge, then just turn the forge off and leave the file IN the forge for an hour to slowly cool down.

I will be at DMS tonight after around 6pm if you’d like me to handle the forge firing. You’d need to bring your own BBQ propane tank (and the file). Plan on 90 minutes including setup, heating, cooling, and cleanup.

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#8

That would be awesome, thank you. I have a tank on the grill that has seen one use. I’ll bring it.

I’ll still be in Tuesday’s class. :slight_smile:

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#9

Mike,

Thank you for the help tonight! I put the forge back after it cooled down, but the files were still hot enough after 45 minutes to require tongs to remove. I put them down on the concrete ridge for the ramp then wrapped them in a cotton shirt so I could carry them to the truck. :slight_smile:

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#10

This is actually a good thing: the slow cook down is the main part of the annealing process as it allows the metal’s crystalline structure to relax and soften.

Good luck with your knife.

#11

For the cool down I would recommend pearlite rather than vermiculite. Vermiculite holds water so it will be a lot like a quench rather than an anneal, Pearlite is not anhydrous. Vermiculite works well if you heat it to above boiling for an hour or two in an over before putting your tool steel in it.

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#12

Burying the steel in a large bucket of dry, cold wood ash is the traditional method.

I know from my dutch oven cooking ash can that hot coals buried in ashes can stay hot for a LONG time.