Author Topic: Piston for Corliss  (Read 1232 times)

Offline vcutajar

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Piston for Corliss
« on: January 25, 2014, 05:43:09 PM »
Hi guys, it's me again.

So today I was going to start work on the MEM Corliss piston and the plans give a choice of either making it with mild steel or cast iron.  The cylinder block is made from mild steel.  I am under the impression that the cylinder and the piston should not be made from the same material.  Am I correct?

In the meantime I managed to find a small piece of cast iron (left over from the Kiwi build) and was thinking of making the piston from cast iron.  If I need to remake the piston, can I use brass or bronze?

Regards

Vince

Offline Florian Eberhard

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Re: Piston for Corliss
« Reply #1 on: January 25, 2014, 05:48:34 PM »
Hi Vince

Yes, it is better not to make the piston and the cylinder from the same material.
Actually, if you are going to run it with pressurized air(since you are using mild steel), I would propose to make a brass piston with teflon piston-rings. I would even say make them seamless, they can be expanded with a cone and after that you compress them again with a funnel shaped ring (only slightly tapered).

Regards
Florian

Offline vcutajar

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Re: Piston for Corliss
« Reply #2 on: January 26, 2014, 12:25:41 PM »
Thanks Florian for your suggestion.  As I have started the piston with cast iron I will see how that works out.  If it has to be remade it will be done in brass.

Regards

Vince

Offline Florian Eberhard

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Re: Piston for Corliss
« Reply #3 on: January 26, 2014, 08:56:45 PM »
Hi Vince
 
I think cast iron will work as well as brass would. Just has to be something different than the cylinder is made of (and cast iron has some graphite in it which is also helpful when there is not enought lubrication)

Regards
Florian

PatJ

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Re: Piston for Corliss
« Reply #4 on: February 06, 2014, 07:47:02 PM »
Cast iron works well running on cast iron, and that is how most of the old engines were made.
I would think cast iron running on steel would also work well.

I am a big proponent of making cast iron rings.
Cast iron rings, if made correctly, will basically last forever, and will operate under any heat conditions that the engine will encounter.

Pat J