How long life for piston graphite ??

Discussion on Stirling or "hot air" engines (all types)
Post Reply
thanh-cuibap
Posts: 164
Joined: Tue Sep 06, 2016 8:09 am
Location: Việt Nam

How long life for piston graphite ??

Post by thanh-cuibap » Wed Oct 12, 2016 7:37 am

Hello everyone !! anyone can tell me how long life for piston graphite ??

Ian S C
Posts: 2221
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: How long life for piston graphite ??

Post by Ian S C » Thu Oct 13, 2016 2:04 am

If the cylinder is highly polished in the bore, the graphite piston will last indefinitely, any roughness and the piston will be destroyed quickly.
Ian S C

thanh-cuibap
Posts: 164
Joined: Tue Sep 06, 2016 8:09 am
Location: Việt Nam

Re: How long life for piston graphite ??

Post by thanh-cuibap » Thu Oct 13, 2016 2:24 am

Thanks Lan S C !

thanh-cuibap
Posts: 164
Joined: Tue Sep 06, 2016 8:09 am
Location: Việt Nam

Re: How long life for piston graphite ??

Post by thanh-cuibap » Thu Oct 13, 2016 2:41 am

I'm improving my stirling engine and consider between piston made of graphite, aluminum and rubber membrane,. you can show me make a highly polished in the bore cylinder ??

Ian S C
Posts: 2221
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: How long life for piston graphite ??

Post by Ian S C » Fri Oct 14, 2016 1:30 am

After you have bored the cylinder in the lathe it will have (hopefully) very light machine marks, to get rid of these start with a brake cylinder hone until the bore is an even gray all over, then you need a tight fitting piece of reasonably hard wood. Put a split in this length wise, this is so you can adjust the diameter either with a wooden wedge, or a wood screw. Coat this with fine grinding paste. With the lap mounted in the lathe chuck, and the cylinder on the lap, start the lathe and hold the cylinder with your hand and move it back and foreward, it will take quiet a while. Check that the bore is parallel. After you have finished the cylinder, then make the piston. I'v never made graphite pistons, but they are not too hade to make, initially take it down to near size, it just about to enter the cylinder, now leaving it in the lathe get some strips of ordinary paper, hold this over the piston as you would a bit of abrasive cloth over a bit of steel, the paper is enough to take off the last fraction and leave a polished surface.
Many have had success with the rubber diaphragm. Aluminium rubbing on any metal has high friction (some commercially made motors use Aluminium), the best metal is cast iron. Ian S C

thanh-cuibap
Posts: 164
Joined: Tue Sep 06, 2016 8:09 am
Location: Việt Nam

Re: How long life for piston graphite ??

Post by thanh-cuibap » Fri Oct 14, 2016 2:51 am

Thanks Lan S C !

masaruneema
Posts: 31
Joined: Thu Sep 10, 2015 1:54 am

Re: How long life for piston graphite ??

Post by masaruneema » Mon Oct 17, 2016 8:59 pm

Hello everyone !! :big smile:
จีคลับ 1688

thanh-cuibap
Posts: 164
Joined: Tue Sep 06, 2016 8:09 am
Location: Việt Nam

Re: How long life for piston graphite ??

Post by thanh-cuibap » Wed Oct 19, 2016 3:04 am

:big smile: hi !

Post Reply