1144 Stress-proof equivalent in Europe?

[DiegoVV]

Hi fellow members,

For the crankshaft of my next project (An Offy 270), the plans asks for 1144 to make the crankshaft. I understand that this steel combines great machineability with low internal stress that will help in keeping it straight when removing large amounts of material.

The problem is that I don´t seem to find the equivalence of 1144 in the European standards. Does any colleague from the old side of the world have any suggestion?

Thank you all!

 

[Bessemer20]

The European equivalent of 1144 stress proof steel is typically considered to be EN 10088: 44SMn28 under the European standard, which is a steel grade with similar properties to 1144 steel, particularly its high strength and good ductility.

 

[TonyM]

EN 10088 is stainless steels standards. https://bssa.org.uk/bssa_articles/c...BS EN 10088-3 is,duplex), grades are included.

 

[Bessemer20]

That was what come up in a quick Google search.

 

[TonyM]

The nearest chemical composition is probably EN16C That probably makes it easy to machine but "stressproof" relies more on the production method than composition.

 

[djc]

That was what come up in a quick Google search.

What comes up in a slower, more thorough Google search?

If the doctor told you you were to die tomorrow, you would probably seek a second opinion before going public with the news.

This is quite comprehensive (but does not contain 1144):

https://www.michael-smith-engineers...o/MATERIAL-GRADE-COMPARISON-TABLE-for-Web.pdf

This has 1140 and 1146 on it, also downloadable as a pdf:

https://www.hastingsmachine.com/steel-grade-equivalency-table-3/

 

[Bessemer20]

What comes up in a slower, more thorough Google search?

If the doctor told you you were to die tomorrow, you would probably seek a second opinion before going public with the news.

This is quite comprehensive (but does not contain 1144):

https://www.michael-smith-engineers...o/MATERIAL-GRADE-COMPARISON-TABLE-for-Web.pdf

This has 1140 and 1146 on it, also downloadable as a pdf:

https://www.hastingsmachine.com/steel-grade-equivalency-table-3/

And here comes the real reason I try not to help anyone on a public forum...

 

[Nerd1000]

Stress-proof seems to be a US special, I certainly wasn't able to get anything close in Australia.

You might consider alternative grades. The main requirements are sufficient hardness to run against the bearings and sufficient strength to avoid bending the crank. Below are 3 options which all meet the hardness required:

1045 or C45 will provide similar mechanical properties to 1144 but somewhat more difficult machining.

4140 or 42CrMo4 will be stronger and more challenging to machine.

Ductile iron (EN-GJS-450-10) will be easier to machine with minimal distortion in my experience. However its strength is only comparable to mild steel. This may well be sufficient, often in model engine parts 1144 is chosen more for its hardness and machinability than its tensile strength.

 

[ChazzC]

Hi fellow members,

For the crankshaft of my next project (An Offy 270), the plans asks for 1144 to make the crankshaft. I understand that this steel combines great machineability with low internal stress that will help in keeping it straight when removing large amounts of material.

The problem is that I don´t seem to find the equivalence of 1144 in the European standards. Does any colleague from the old side of the world have any suggestion?

Thank you all!

Since it doesn’t appear that there is an equivalent, why not buy some 1144 and have it shipped?

 

[djc]

And here comes the real reason I try not to help anyone on a public forum...

It is well-known that the internet is a fickle mistress. Even for your own use, it is not wise to trust the first answer you get. If that answer is going to be used to assist someone else, doing your very best to ensure it is correct before posting it would seem to be even more important.

 

[michael-au]

Since it doesn’t appear that there is an equivalent, why not buy some 1144 and have it shipped?

Shipping from the US is super expensive
I had some shipped back in 2015 1' x 36" the 1144 was $22 us and postage was $29 us
also in 2017. 2" x 24" 1144 cost of steel $56us postage $58us
I think there would be a big increase it the price of the steel and the postage since then not to mention the exchange rate

That was from Amazon US it was the best I could find at the time, I don't think there any sellers on there now that ship to Australia

 

[Jasonb]

The main reason stressproof is specified for model crank shafts is not it's strength or hardness. It is due to it's specific method of manufacture that leaves little or no stress in the material. This means when you take unbalanced cuts out of the side of it as you do when making a crank it won't end up like a bananna.

It is a trade name not a specification.

You can do your best to avoid the part moving by using hot rolled or stress relieving bright bar. Then rough out and leave it on the bench for a few weeks before final machining. EN8 (080M40)or EN8M (212M36) in the hot rolled form would be a reasonable choice and is what is specified on a lot of UK designs for model engine crankshafts

 

[Charles Lamont]

It is well-known that the internet is a fickle mistress. Even for your own use, it is not wise to trust the first answer you get. If that answer is going to be used to assist someone else, doing your very best to ensure it is correct before posting it would seem to be even more important.

Exactly. Anybody with a qestion will almost certainly already have done 'a quick Google search'.