12L14 Uses

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A-2 Hardens at 1750 so you got to get it really hot to make it hard .It usually gets hard when your working with small diameter stock and your thru drilling and the id is close to od. A thin wall . You need to keep it flooded with oil . I have been working with A-2 /D-2 for the last 35 years .I make my cams from A-2 cranks from 1144 or 4130 . My rods from 4130.
 
That was typo
I have made punch and dies from A2 and did not see typo.
It is almost as bad as 400 stainless steel. A machinist will have magnet in tool box for type 400 stainless steel.
Type 300 is non magnetic and dies work harden like 400 does.
I have had few machinist over the years refused to machine A2 or type 400 stainless steel.

Dave

Interesting - I have not had any experience with any of these, unless A1 is equivalent to A2. The latter I have used for a few projects, and never had any trouble machining it - and it hardens beautifully. But as best I recall, though I have drilled A2, I've never tapped it - that might be a test of its work-hardening characteristics.
 
Personally I use 4340 for all of my cranks... It and be a little difficult sometimes to mach but the trade off is its strength.. 316ss for my valves and LM4 bronze for valve and valve followers..O2 for my cam profiles as it tends to work harden over time...I try to use bronze for valve timing gears and the like....Ive been a toolmaker for almost 60 years and you would think making small engines would be boring after all these years but it keep the brain matter active haha Almost finished a 5 cyl radial thats going to go in a 120"Skymaster
 
There a are types of steel I would avoid 400 type stainless steel, D2 tool steel and A1 tool steel. They are so mush fun one miss stake and they are harder than rock.

Dave

303 and 416 stainless are my go to steels when I want to use stainless. Neither work hardens significantly in my experience. Type 416R is the standard SS used by gun barrel makers world wide.
 
416 is a free machining stainless steel.
Still work harden but not as bad as other 400 stainless.
Some 400 stainless will work harden like grass.

I did put chart at bottom if notice the chart shows most 400 around 40% but look at cast iron. The chart does not tell the whole story.

Dave


303 and 416 stainless are my go to steels when I want to use stainless. Neither work hardens significantly in my experience. Type 416R is the standard SS used by gun barrel makers world wide.

Machinability of Metals Based on 100% machinability for AISI 1212 steel
Carbon steel: Percentage
1015 72%
1018 78%
1020 72%
1022 78%
1030 70%
1040 64%
1042 64%
1050 54%
1095 42%
1117 91%
1137 72%
1141 70%
1141 annealed 81%
1144 76%
1144 annealed 85%
1144 stressproof 83%
1212 100%
1213 136%
12L14 170%
1215 136%





Alloy steels:
2355 annealed 70%
4130 annealed 72%
4140 annealed 66%
4142 annealed 66%
41L42 annealed 77%
4150 annealed 60%
4340 annealed 57%
4620 66%
4820 annealed 49%
52100 annealed 40%
6150 annealed 60%
8620 66%
86L20 77%
9310 annealed 51%

Stainless Steel and Super Alloys:
302 annealed 45%
303 annealed 78%
304 annealed 45%
316 annealed 45%
321 annealed 36%
347 annealed 36%
410 annealed 54%
416 annealed 110%
420 annealed 45%
430 annealed 54%
431 annealed 45%
440A 45%
15-5PH condition A 48%
17-4PH condition A 48%
A286 aged 33%
Hastelloy X 19%

Tool Steel:
A-2 42%
A-6 33%
D-2 27%
D-3 27%
M-2 39%
O-1 42%
O-2 42%

Gray Cast Iron:
ASTM class 20 annealed 73%
ASTM class 25 55%
ASTM class 30 48%
ASTM class 35 48%
ASTM class 40 48%
ASTM class 45 36%
ASTM class 50 36%

Nodular Iron:
60-40-18 annealed 61%
65-45-12 annealed 61%
80-55-06 39%
Aluminum and Magnesium Alloys:
aluminum, cold drawn 360%
aluminum, cast 450%
aluminum, die cast 76%
magnesium, cold drawn 480%
magnesium, cast 480%
 
Bare 12L14 loves to rust, even in relatively low-humidity NorCal where I live. I think the places where the lead particles break the surface act like little corrosion cells. By contrast, plain carbon 1018 can be left bare in my garage for years with not much corrosion happening.
 
I have lot of both 1018, A36 and 12L14 they all Rust about same.
All three needs paint or plating or they will rust.

Dave

Bare 12L14 loves to rust, even in relatively low-humidity NorCal where I live. I think the places where the lead particles break the surface act like little corrosion cells. By contrast, plain carbon 1018 can be left bare in my garage for years with not much corrosion happening.
 
Has anyone ever heard of C1139 cold rolled? Back 45 years or so when I was making reloading tools I used what I recall as c1139 but I cannot find any reference to it now. It seems to be very close to 1144. I still have some .75, 1, 1.25 and as I remember it was fairly low in carbon but would harden enough for some tools and machined very nicely. Has my memory gone the way of the rest of my body? Ted
 
The C1139 would very odd steel. I think dates back to World II. There maybe special rolling by a mill.

The 1144 was around at over 45 years ago.

I did check steel supple books from 1970's and no listing of C1139.

I think I remember C1139 is my Machinists Hand book from 1941

Dave

Has anyone ever heard of C1139 cold rolled? Back 45 years or so when I was making reloading tools I used what I recall as c1139 but I cannot find any reference to it now. It seems to be very close to 1144. I still have some .75, 1, 1.25 and as I remember it was fairly low in carbon but would harden enough for some tools and machined very nicely. Has my memory gone the way of the rest of my body? Ted
 
The C1139 would very odd steel. I think dates back to World II. There maybe special rolling by a mill.

The 1144 was around at over 45 years ago.

I did check steel supple books from 1970's and no listing of C1139.

I think I remember C1139 is my Machinists Hand book from 1941

Dave

Thanks for the info Dave...it is good to know that I can remember some things. The c1139 that I have was purchased from a local scrap yard/metals/equipment company in Billings, Montana in the early to mid-seventies. It was a very old company so no telling how long the stock had been in their inventory.
 
Glad to here it help you.
If ever make to Billings, Montana Airport you see what use to manufacturer Aircraft Hangar Doors. If look at the hands or wheels you see the name Smith.

Dave

Thanks for the info Dave...it is good to know that I can remember some things. The c1139 that I have was purchased from a local scrap yard/metals/equipment company in Billings, Montana in the early to mid-seventies. It was a very old company so no telling how long the stock had been in their inventory.
 
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The engines here are models.

Finally! Someone has similar views on the subject. We're making expensive toys. Use whatever material works for you. There is no right or wrong material, method, tool, etc. You get to decide what's right or wrong.

(That is, unless you rip your arm off in a machine. Then I'd say you were wrong.)

...Ved
 
Hi Ted & All:
It has been a while (1954) since my high school metaluregy class but if I am right the
last two digits 39 stand for percent of carbon and the ability for it to harden. 39 is close
to the 40 of 4140 a very common steel for hardening, so I think this is why it worked so
well for you to harden for tools.
Bill Thomas
 
The first two digits shows 11 is easy-to-machining has manganese. The C is carbon steel and the last two digits like you said is percentage of carbon.
This steel dates back to World war II.
The steel that replace/sub is 1144 stressproof.

Dave

Hi Ted & All:
It has been a while (1954) since my high school metaluregy class but if I am right the
last two digits 39 stand for percent of carbon and the ability for it to harden. 39 is close
to the 40 of 4140 a very common steel for hardening, so I think this is why it worked so
well for you to harden for tools.
Bill Thomas
 
I only use 12L14 as a substitute for 1018 Cold Rolled Steel, typically for when I want something that turns more freely for example if I have to single point a threat that I don't have a die for. For cylinder liners I always use cast-iron (or chrome-moly if the walls are too thin for CI), and for crank shafts I always use at least 1144-SP if not chrome-moly, and for cam shafts I always use hardened chrome-moly or drill rod and grind them. I would never use 12L14 as a substitute for alloy steel or tool steel.
just my 1.414 cents,
Peter.
(one exception, I made the finned cylinders for a radial engine out of 1144-SP rather than CI, time will tell if that is a regrettable choice or not)
 

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