Heat Treating Question

[jdmboyd]

Hey folks,

Hope everyone's doing well during the shutdown.

Heat treating question: My '80 80 FLH is lowered; learned how that was done while rebuilding by forks and replacing the sliders recently. So anyway, the stock kickstand has always been too long, metastable to tipping over with the wheel turned to the right so I decided to shorten it. First, heated it with an oxy-acet torch then flattened out the stock bend in a press. Then figured where I needed to bend it to shorten it an inch, reheated it to orange hot, stuck it in a vise and bent it by hand. Did this twice to fine tune the angle, then let it air cool.

So, should I reheat this thing, then quench it in water to harden it or leave it as it is? Not sure what degree of hardness and ductility I need here and how to get it. Any advise appreciated.

Thanks for your help.

John

[Guest]

don't quench in water, its often too much of a shock to the steel & can make steel brittle, quench in oil like they do in the TV show 'Forged In Iron' ...

[DustyDave]

For a kickstand what you did should work for years and years. Water quench the very end of a cold chisel but don't make that kickstand brittle. Sudden instantaneous failure is spectacular but proly not what you want.
Dusty

[KG]

Not enough carbon in mild steel to really matter.

[DustyDave]

Not enough carbon in mild steel to really matter.

But quenching will cause it to be more susceptible to fatigue cracks.
Dusty

[KG]

But quenching will cause it to be more susceptible to fatigue cracks.
Dusty

Agreed. If quenched you would need to temper it back a bit. Like 1 hour at 400 degrees.

Heating and cooling to room temp in air puts it in a normalized state. Slow cool in wood ash over hours gets it annealed(softest state).

I’ve quenched mild steel (.18% carbon) in cold water with no temper and tried to break it wit a hammer. No such luck. I’ve dropped hardened high carbon steel (.95% carbon) after quench (b4 temper) and had it shatter. It’s all about the carbon content.

[flatman]

Not to be off topic but what about valves. I need to shorten a valve tip and need to reharden it. Got to take about 60 thousand off the end. I had to harden a drill rod made JD pushrod once and the guru here (RIP) told me to do it in salt water. Seemed to work. Also have some of that cherry red stuff (kasenit is nla) but never tried it. Valves are usually made of some good stuff. Only thing I know is its not Stainless steel. Thanks

[KG]

Use caution with valves. Their alloys very and can have reactions, I’ve herd even explosions. Alloy steels have divers heat treatment requirements. Some need an hour “soak” at 1950 degrees before quench. Some are air hardening ie room temp cool down equals quench. Others need oil, water or brine(slow to fastest quenchants).
Id recommend keeping the heat out during cutting. Heat colors can be seen. The rainbows around welds are examples of that. If you don’t have those colors show up no re-heat treatment needed.
Hay/gold color is ok, blue is a bit much and purple is to much heat and affecting the overall hardness.
If you do heat treat be sure to temper it back for toughness. Cook in the oven at 400 degrees for 1 hour. If piece is polished you will see the hay color through(most steels, but not all).

[KG]

A good read on valve materials and design...

http://www.sbintl.com/tech_library/articles/understanding_valve_design_and_alloys.pdf

[MOTher]

With the shutdown and having a lot of time on your hands, you may be overthinking it. I had the same problem with the kickstand on a Sportster. I rode it over to the shop, fired up the torches, heated the bend of the kickstand cherry red, leaned it over to a comfortable lean, stood it back up (I was sitting on it the whole time) then leaned it on the right against the doorway and went inside and shot the shit while it cooled down. Never gave me any problem. No hardening, no tempering, just heat bend, let it cool. The only caution was to aim the torch so as to not heat the spring. And, not that it matters, but the TV show is "Forged in Fire" one of my favorites.

[flatman]

thanks kg!

[jdmboyd]

Folks,

Thanks for the input. I wound up giving it a 10W30 quench after about 5 min at bright orange around the bend area; not real scientific nor controlled. After about a minute the smoke and bubbling stopped; after about ten I pulled it out and set it aside for the rest of the day while I continued working on other things. Tonight I hit it with a little Dobie pad and Comet; a lot of the surface black was removed, but not all.

I'm guessing this'll work. If the angle's wrong at least I know how to dial it in; thanks Muther.

And yeah, too much time and overthinking. But, as a buddy says, if it's worth doing, it's worth overdoing...

John

[farmall]

Valves and anything hardened may be ground without overheating. Take shallower cuts and leave plenty of cooldown time. You can speed cooling as you would sharpening a drill or lathe tool by dipping it in water when it gets even slightly warm.

Your local machine shop should have a heat treating oven and the foil to wrap parts. You could determine the required spec and have them precisely heat treat your part. Bikers should get more use from their local machinists. Machine shops have Rockwell testers and can verify hardness.

[JBinNC]

Most all modern valves have a stellite or other hardened tip. Trying to remove as much as .06 from the tip will pretty much eliminate that hardened tip. There are shops that specialize in shortening valves and adding the hardened tip. You usually start with a valve blank, cut to length, add the tip, and then cut the keeper groove. This is rather specialized work as you might imagine. You can avoid using the hardened tip by using a lash cap, and keepers cut for the cap.

As far as heat treating parts that are already heat treated, it really don't work that way. You would have to know the exact alloy, do a full anneal, and then heat treat. Any finish work such as grinding the valve stem to size would be spoiled by that much processing. I've done a lot of heat treating of tool steels in a shop setting, and re-heat treating something like a finished valve is just a no-go.

Jim

[JBinNC]

Folks,

Thanks for the input. I wound up giving it a 10W30 quench after about 5 min at bright orange around the bend area; not real scientific nor controlled. After about a minute the smoke and bubbling stopped; after about ten I pulled it out and set it aside for the rest of the day while I continued working on other things. Tonight I hit it with a little Dobie pad and Comet; a lot of the surface black was removed, but not all.

I'm guessing this'll work. If the angle's wrong at least I know how to dial it in; thanks Muther.

And yeah, too much time and overthinking. But, as a buddy says, if it's worth doing, it's worth overdoing...

John[ATTACH=CONFIG]102360[/ATTACH][ATTACH=CONFIG]102361[/ATTACH]

Because these jiffy stand legs are medium carbon steel, like maybe 1144, some toughness could be gained by a heat and quench, and then a draw back. BUT, every time you heat steels like this to a red heat, you are pulling the carbon out of the matrix, essentially softening the metal and reducing the effective carbon content. It would have been better to quench the work the first time you heated it, as you probably did more damage by heating it a second time. But the alloy is tough (if it's a factory piece) and will probably survive and serve you well.

Jim