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: rodnoc on July 29, 2022, 12:09:03 am

Title: Microcosm o-rings
Post by: rodnoc on July 29, 2022, 12:09:03 am

Do any of you know a source of odd-sized o-rings?

I need 15.2mm ID x 1.8mm ring width, and 15.5mm ID x 1.6mm ring width.  These are used in some Microcosm water-cooled engines but are not currently available as spare parts. 

I’ve tried McMaster, even requested a special order, but no joy. 

Title: Re: Microcosm o-rings
Post by: Fullraceflathead on July 29, 2022, 08:33:43 pm

I think you may find that those are actually SAE size rings. If you convert those mm into inches they come very close to some standard overing sizes that are in inches.

Title: Re: Microcosm o-rings
Post by: rodnoc on July 29, 2022, 09:09:24 pm

"Close" won't work, I've tried.  I got those mm o-ring sizes from Microcosm, they are for the H74 and M18.

Title: Re: Microcosm o-rings
Post by: rodnoc on August 04, 2022, 07:14:31 pm

Microcosm has added two more o-ring grooves per cylinder on three of their engines.  The ad doesn’t say that o-rings are included, though.

“This is the cylinder body and cylinder set used by H75, H74, and H73 engine.
It is equipped with four O -ring sealing water channels. Solve the problem of cylinder leakage.”

https://tinyurl.com/2d6np5na


Lets hope Microcosm makes spare o-rings available for all of their water-cooled engines.  Please, Jin.

Title: Re: Microcosm o-rings
Post by: rodnoc on August 08, 2022, 06:19:44 pm

Water-jacket o-rings for the H74 and M18 are now available at Microcosm.

H74
https://tinyurl.com/yxh5e92s

M18
https://tinyurl.com/3yputpjz

Title: Re: Microcosm o-rings
Post by: RedRyder on September 01, 2022, 04:36:36 pm

My H74 and H75 both came with spare o-rings.