1018 or 4140

[fdew]

I want to make a crank shaft from one piece of steel. Stock will be .75 X 2 in X 12 in
I can get 1018 or 4140 steel

What do you think?

Frank

 

[steamer]

First Choice...neither

1144 stressproof. Works great and machines nice.

1018 is good for low power hit and miss engines....but not much more

4140 is fabulous for any crank...but machining it will be a bear...


Dave

 

[fdew]

Thanks, I should have added that this is for a "steam engine" that will probably only see compressed air.
It was designed around a 5 piece crank but I would rather try one piece.

Frank

 

[steamer]

A show engine running slow, turn it from what ever you like

I would consider 12L14 for this as it's strength is very good, and it's stable

1018 stress relieves in the Cold rolled form

Dave

 

[Philjoe5]

I too vote for 1144 steel. Whenever I machine the stuff I keep a smile on my face ;D. It hasn't disappopinted me yet

Cheers,
Phil

 

[fdew]

I too vote for 1144 steel. Whenever I machine the stuff I keep a smile on my face ;D. It hasn't disappointed me yet

Cheers,
Phil

1144 seems to be available only in round stock. Because the crank has only one throw I was planning to make it from 3/4 X 2 in plate.

Frank