Author Topic: Questions on heat treating and tempering high carbon trade points.  (Read 4968 times)

0 Members and 1 Guest are viewing this topic.

Offline Mafort

  • Member
  • Posts: 424
So I’ve got a few bits of high carbon (1085) sheets at 16 gauge. I want to heat treat them and temper them for a good cutting edge. I watched a video on YouTube about heat treating and can pretty much do that myself but my main question is with the tempering. Can I heat it up again on the makeshift “forge” (it’s essentially bricks in a circlish shape with a hair dryer) and heat to a or even blue coloring and do it that way or is that not efficient enough to temper the heads. Keep in mind these heads will be tanged. They’ll be about 2.5in long (including tang) x 1.25in wide. I’ve never really done this sort of thing on my own so I’m seeking some advice from you guys here. I was wanting to do them a dozen at a time. Hopefully use what I need and sell(Yes I said the forbidden word)/trade the rest.

Offline dylanholderman

  • Member
  • Posts: 787
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #1 on: June 10, 2020, 04:51:32 pm »
you can certainly temper over your forge but it demands higher skill and is easier to over shoot your temp, you will also want to watch how heating affects the flatness of them sense they are such thin stock. heating one side could cause them to curve, i'd do some practice runs with scrap/mild steel of the same thickness to get your process down.

also this might be of interest to you
quoted from another forum that was talking about slipjoint knives link https://www.bladeforums.com/threads/1095-tempering-for-springs.592430/

I don't recommend the following technique, but here is a good example of Bill Moran's unique brand of metallurgy.

Bill Moran told me how he tempered all the springs he made.
He had a black ,charred looking baking pan that sat beside his forge ( you may have noticed it in his shop). He would get the coals burning real low. Then he laid the springs in the pan, added kerosene (yes kerosene) until it just covered the springs. He set the pan on the coals, letting the kerosene heat up, ignite, and start to burn ( This happens at about 550F). He would pull the pan off the coals before the kerosene was gone, and set it on his anvil to finish burning and cool off. He claimed he never had a spring fail doing it this way ( springs probably reached around 650F). He was taught this trick by an illiterate blacksmith.( Bill said, " He couldn't read books, but he sure could read steel !")

By relying on the flash point of kerosene to be his guide to temperature, he had a fairly accurate spring temper ( kept accurate by never varying the circumstances that the temper was done under.)

Offline Mesophilic

  • Member
  • Posts: 876
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #2 on: June 11, 2020, 11:42:16 am »
I do my tempering in the toaster oven for small to medium items and the kitchen oven for large pieces.

I use an oven thermometer to monitor the temps.  Pre heat and adjust settings to maintain a stable temperature, and expect the temp to drop for a little bit once you put the pieces in.

I've messed around with heat treating points.  Expect some to warp.  Some points are fairly easy to atraighten during a second tempering cycle, others just go in a scrap pile cause they're too far gone.

Grinding bevels post heat treat can help to minimize warping, just dunk in water frequently so you don't ruin your heat treat.
Trying is the first step to failure
-Homer Simpson-

Offline Mafort

  • Member
  • Posts: 424
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #3 on: June 17, 2020, 04:09:44 pm »
I do my tempering in the toaster oven for small to medium items and the kitchen oven for large pieces.

I use an oven thermometer to monitor the temps.  Pre heat and adjust settings to maintain a stable temperature, and expect the temp to drop for a little bit once you put the pieces in.

I've messed around with heat treating points.  Expect some to warp.  Some points are fairly easy to atraighten during a second tempering cycle, others just go in a scrap pile cause they're too far gone.

Grinding bevels post heat treat can help to minimize warping, just dunk in water frequently so you don't ruin your heat treat.

So another question. Would it be better to cut 2.5x2 inch sheets And do the heat treat and temper process while it’s a sheet and cut out the point afterward be better to ward off warping?

Offline dylanholderman

  • Member
  • Posts: 787
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #4 on: June 18, 2020, 11:00:56 pm »
it's not a bad idea but you introduce another problem in exchange, that is depending on what tools you're using you run the risk of over heating the point and having to redo the heat treat anyway  :-\

not trying to discourage you from that rout, i use old saw plates without re-heat treating them, you just have to take a little bit of extra care to keep them cool.

Offline Mafort

  • Member
  • Posts: 424
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #5 on: June 19, 2020, 06:16:17 am »
So I could dip them in water every few minutes or so to keep them cool?

Offline Mr. Woolery

  • Member
  • Posts: 110
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #6 on: June 19, 2020, 10:44:21 am »
This sounds primitive, but that’s appropriate on this forum: if you are working with steel that’s already hard, work without gloves. If it gets warm enough to be uncomfortable, dip it in water. Depending on your tools, you can spend more time in the water than on the abrasive.

Personally, I like to get blades to almost finished dimensions before heat treat. A final grind is seldom more than 5% of the steel I remove in total. That said, every smithy is different. My approach might not work on your tools.

I suggest trying a couple that are almost finished when you harden. If they warp, then try hardening before shaping.

Patrick

Offline willie

  • Member
  • Posts: 3,268
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #7 on: August 03, 2020, 04:43:22 pm »
Quote
So I’ve got a few bits of high carbon (1085) sheets at 16 gauge.

Hi, just curious if you found scrap or repurposed something to find 16 ga in 1085? I guess it can be ordered, but finding it otherwise would be cool.

Offline Mafort

  • Member
  • Posts: 424
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #8 on: August 03, 2020, 05:38:17 pm »
I ordered some online off eBay. It was listed as carbon steel and I asked the seller and I got it’s 1085 as a response

Offline Woody roberts

  • Member
  • Posts: 179
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #9 on: September 03, 2020, 10:03:15 pm »
Ive haven’t made points yet but I have made several knives. I never saw anyone say anything about normalization. I normalize my knives at least three times before I quench and rarely get a warp.

Offline Woody roberts

  • Member
  • Posts: 179
Re: Questions on heat treating and tempering high carbon trade points.
« Reply #10 on: September 03, 2020, 10:07:16 pm »
Ps. Ive also never worked with 1085. Mostly I repurpose stuff. Lawn mower blades. Truck springs etc.
I do use O1 to make reamers with. I temper in the kitchen oven.