Red neck heat treating.

[NASTYZEN]

Some times there's a rush job that needs to be rushed. No time for the heat treaters.

Heat t'ill desired temperature.



Seriously, to be done out doors with a fire extinguisher! In a well ventilated area.

Used motor oil. This color is about right for what I need. I'm using 4140 alloy.



Moving the part around while quenching keeps the bubbles away from the part and keeps part-oil contact better which is preferred.

I have a bigger can I was using, but the oil was getting so hot from the other quenchings that I used this small one to finish the job before setting everything on fire.



Mission accomplished. I wish the payment would be as rush as the job was.

 

[DoghouseForge]

I would like to add the additional info for the redneck high temo thermometer...

Slap a welding magnet on something close by and keep touching the part to it duting the heating... when it stops reaction with the magnet you have reach "non magnetic" or 1450 degrees and you can be certain you got it to critical hardening temp before you quenched it...



Jp

 

[signcrafter]

That's neat. I've always wondered when and where you would want to heat treat something. It makes it stronger but also more "brittle" right? I make a lot of homemade tools and other stuff and have often wondered if some things should be heat treated. Like a prybar or something where more strength would be a plus but from how I understand it if you put to much force onto the heat treated prybar instead of bending it will just snap or shatter. Don't mean to hijack this thread, just something I've always wondered but never took the time to look into.

I made this lower control arm tool last year sometime. It's a copy of the lock technologies tool,

. Here is my thread on making it, http://www.garagejournal.com/forum/...22&highlight=lower+control+arm+tool&showall=1. One of the parts bent a little when I put a lot of pressure on it. I though heat treating might have helped there but was also worried that instead of just bending it might snap and be dangerous? Was thinking about fabbing up a new part bracket using thicker metal but not sure what the best option would be. Any advice?

 

[JSGAuto]

How did you test you reached full hardness?

How did you temper the part to the desired strength?

 

[OccupantRJ]

Try some A2 or S7 shock tool steel. Heat it up really red, then let it cool in air. They are both air hardening. Rewarm to a few hundred degrees to temper, if needed. I have experimented for 25 years with torch heat treating, and now I only have one die part I make sent out for heat treating, as it has a long slot in it and will curve if not run through all the proper procedures. Most of our dies are smaller dies under 100 lbs, and consist of smaller parts. The magnet trick mentioned above is a good one to use. I don't even bother with O1 oil hardening any more.

 

[NASTYZEN]

I would like to add the additional info for the redneck high temo thermometer...

Slap a welding magnet on something close by and keep touching the part to it duting the heating... when it stops reaction with the magnet you have reach "non magnetic" or 1450 degrees and you can be certain you got it to critical hardening temp before you quenched it...



Jp

I already new about the magnet method, thank's for pointing it out. Eye balling the proper temp was adequate for what the parts were for.

I made this lower control arm tool last year sometime. It's a copy of the lock technologies tool,

. Here is my thread on making it, http://www.garagejournal.com/forum/...22&highlight=lower+control+arm+tool&showall=1. One of the parts bent a little when I put a lot of pressure on it. I though heat treating might have helped there but was also worried that instead of just bending it might snap and be dangerous? Was thinking about fabbing up a new part bracket using thicker metal but not sure what the best option would be. Any advice?

I would just beef up the lever with gussets and thicker walled tubing?

How did you test you reached full hardness?

How did you temper the part to the desired strength?

I did not test it after.
I heated it up and quenched it in oil..

Try some A2 or S7 shock tool steel. Heat it up really red, then let it cool in air. They are both air hardening. Rewarm to a few hundred degrees to temper, if needed. I have experimented for 25 years with torch heat treating, and now I only have one die part I make sent out for heat treating, as it has a long slot in it and will curve if not run through all the proper procedures. Most of our dies are smaller dies under 100 lbs, and consist of smaller parts. The magnet trick mentioned above is a good one to use. I don't even bother with O1 oil hardening any more.

Yeah, A2 is a cool alloy.It would of been perfect for the job. I only have some 1/2bar of it on hand, but I needed a larger dia. Those bushings were for aligning a fiberglass mold. I keep 4130,4140 and 4340. It's best for most automotive applications because of it's toughness and spring steel qualities.
I use O1 and A2 for tooling applications like dies and punches.

 

[bullnerd]

When I first learned how to do this about 25yrs ago, I watched a guy drop the hot part into a small bucket....made of PLASTIC! I knew what was going to happen but the guy was a know it all so I didnt say anything.

Very cool, thanks for taking the time to post the pics.

 

[BD1]

Do you guys use heat sticks ? http://www.markal.com/temperature-indicators/thermomelt/

Here's what the manufacture states.Thermomelt HEAT-STIK markers are a quick, low-cost method to accurately measure surface temperatures of various metals and equipment. Available in 88 Fahrenheit and 32 Centigrade temperatures, the stick-in-holder design provides convenience and durability for long-lasting use in the workshop or in the field.

 

[JSGAuto]

I did not test it after.
I heated it up and quenched it in oil..

QUOTE]

You did not temper the part, you hardened it when you quenched it in that oil. If you actually reached 1550 degrees, through the entire part, that would put it at HRC60 with a tensile strength or 300KSI. I really hope you finished machining that.....and it is going to be insanely brittle.

To temper you now have to reheat after full hardness and qunch the part in air. The relationship of tensile strength is directly related to the HRC of the material.

 

[OccupantRJ]

Do you guys use heat sticks ? http://www.markal.com/temperature-indicators/thermomelt/

Here's what the manufacture states.Thermomelt HEAT-STIK markers are a quick, low-cost method to accurately measure surface temperatures of various metals and equipment. Available in 88 Fahrenheit and 32 Centigrade temperatures, the stick-in-holder design provides convenience and durability for long-lasting use in the workshop or in the field.

I have used them quite often over the years. A good use is to test plier handles and such before dipping in Plastidip. After they cool, I flame them untill they flash off glossy to set the dip.

 

[bullnerd]

I did not test it after.
I heated it up and quenched it in oil..

QUOTE]

You did not temper the part, you hardened it when you quenched it in that oil. If you actually reached 1550 degrees, through the entire part, that would put it at HRC60 with a tensile strength or 300KSI. I really hope you finished machining that.....and it is going to be insanely brittle.

To temper you now have to reheat after full hardness and qunch the part in air. The relationship of tensile strength is directly related to the HRC of the material.

Yeah tempering by eye is the tricky part. I had a chart that showed all the shades of "straw" that I used to go by. Man been a long time!

 

[Joe69]

Tool manufacturers heat tools to high temps, and quench them. They then heat them to a specified temp, to soften them enough to lessen the brittleness.


Joe

 

[ADCS]

Heat treating metals, whether for tempering, annealing, hardening, etc. is quite the science to do correctly. I think you nailed it on the thread title for this one.

 

[R.Anderson]

To temper you now have to reheat after full hardness and qunch the part in air. The relationship of tensile strength is directly related to the HRC of the material.

Parts after reaching correct tempering temperature via oven temperature or visual temperature color can be quenched in oil or water to stop the tempering process it all depends on the heat treatment process being applied.

-----------

I'm sure Nastyzen knows about tempering in heat treating metals. Have you people seen what this guy has done and can do? If not you should check out some of his threads its impressive. Besides that it's got to be at least halfassed to be a "redneck heat treatment"

 

[Kevin54]

For the ones that hasn't done this, but may attempt it, DO NOT pull the part up out of the oil until it cools some. We've used a torch for quite a few years at work to heat treat smaller parts for dies and such. We had a 30 gallon drum that was half full of quenching oil. I don't know how many times other have swirled the parts around in the oil them pull the part up. As soon as the hot part hits the air, the oil will flame up. You have to dunk it and dunk it fast. I do have to laugh though when ones at work would scream like a little girl and drop their part. then they were up to their elbows in oil trying to fish it out.

 

[madjack]

I do have to laugh though when ones at work would scream like a little girl and drop their part. then they were up to their elbows in oil trying to fish it out.

Seen this happen many times. Think its a hoot. But then I'm somewhat of a sick *******.

 

[Kevin54]

Seen this happen many times. Think its a hoot. But then I'm somewhat of a sick *******.

What I found funny with it, I would tell everyone that went to heat treat like that, to dunk the part quick and swirl it around or it would flare up. So what do they do, they sneak up on it and WHOOOSSH!!!! Flames out of the barrel about 6' high

 

[NASTYZEN]

WHOOOSSH!!!! Flames out of the barrel about 6' high

That's why I switched to the smaller can to harden that last part. I would just get near the hot oil in the first can and it would instantly flare up a couple of feet. I just put a piece of sheet metal on it to put it out.

Just to be clear about this method. It is RED NECK HEAT TREATING. or hardening. No drawing back or anything. it didn't matter for this application. OK?

When I need to get a critical part heat treated, I send it out to the experts. That way, there liable, not me. Besides, I get a detailed printed readout of the entire process to give to the customer.

 

[Kevin54]

That's why I switched to the smaller can to harden that last part. I would just get near the hot oil in the first can and it would instantly flare up a couple of feet. I just put a piece of sheet metal on it to put it out.

Just to be clear about this method. It is RED NECK HEAT TREATING. or hardening. No drawing back or anything. it didn't matter for this application. OK?

When I need to get a critical part heat treated, I send it out to the experts. That way, there liable, not me. Besides, I get a detailed printed readout of the entire process to give to the customer.

We did also. Luckily we had a place 30 minutes away that made 2x weekly trips to our shop, but for small die repairs, punches, we would torch them with the rosebud and quench them in oil. I did a lot of form tools that way because they weren't cutting or shearing, and we didn't have to worry about chipping. I've saw some of the other stuff that other toolmaker had done that way, and the parts ended up with cracks and was glass hard. Depending on the part, we might have drawn some back, by cleaning off the part, then bring it back to a light straw to blue color.

 

[Thumper68]

When I was making replacement blades for our wood chippers this is the method that I used, because it was "good enough" for that part.