Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines
The Regular Stuff: Chat, Buy, Sell, Off Topic, etc. => General Discussion - Scale Model Gas Engines - Hit & Miss - Throttle Governed - Non-Compression – etc => Topic started by: 70Rcode on February 21, 2020, 11:10:52 am
-
Hi Fullrace,..
maybe not...Major o-ring factory application data says Non-lubricated o-rings wear quicker & have higher drag friction.With an obviously Rigid, stainless steel, Mirror Polished Smooth cylinder wall surface finish the majority of surface applied lube oil gets nearly totally wiped clean off by the 1st few strokes (the surface lube oil has No protected void areas to allow oil
migrating into) & subsequent(many) reapeating piston strokes will run o-ring wear damaging dry(bad). So some kind of a Surface finish with zero Rp (rough projecting surface edged Peaks) but with many Rv (smooth edged dimples or angled linear groove Voids) to allow much needed lube oil(good) to migrate into protective surface storage areas A heavily surface Plateaued honed, low Rp, high Rv, fine Crosshatch honed finish could provide the lube friendly cyl wall finish. Somewhere around a 600 grit bore hone followed up with a 800-1000 grit Flex-hone brush could produce the Plateaued low Rp, high Rv effect surface finish. Standard pneumatic o-ringed cylinders might be mfg'd this way. Maybe someone has already tried the o-ring factory suggested cyl wall finish on the M90 like engine & can advise....tom.
-
This would imply that the cylinder is soft and not hard.
-
Hmmmm......I hadn’t noticed.
I will take a look.
-
Hi all,... noticed my M90's factory smooth cylinder wall finish. Has anyone tried the major rubber o-ring mfg's reciprocating application, oil retension friendly, light-fine plateaued crosshatch cylinder finish ? ...i notice after a short run, the cylinder wall looks wiped clean dry by the o-ring...thx, tom.