Author Topic: hit e mis engine  (Read 1541 times)

Offline paolo1959

  • Full Member
  • ****
  • Posts: 24
hit e mis engine
« on: June 08, 2021, 04:15:02 PM »
Hello from Paolo from Italy.
I have the problem of finding the cylinder liners and segments for my internal combustion engines.
Where do you buy them ???
I usually use the red o rings but they do not last long (a few hours of engine operation)
Thank you in advance for your help.
live to save lives

Offline Jo

  • Administrator
  • Full Member
  • *****
  • Posts: 15293
  • Hampshire, england.
Re: hit e mis engine
« Reply #1 on: June 08, 2021, 04:54:15 PM »
Caio Paolo,

If you are making your own model then we normally machine our cylinder liners. They can be made of cast Iron or in Aero engine models steel (EN8) is often used.

The term "segments" has not translated correctly into English: You have mentioned the red silicon O rings so do you mean the rings for the piston? We also turn those up ourselves out of cast Iron. In the UK some of the Model Engineering suppliers will supply them but in limited sizes. You should also be able to buy them in Italy. Think of small IC engines, like Lawnmower engines and see if you can find one with the right bore size.

If the Silicon o rings are not lasting very long it could be that the liner surface is still a little rough. Cast Iron rings "bed in", i.e. wear a little against the cylinder liner this makes the bore of the liner smoother. What this means is you need a better finish on the bore of your cylinder if you are going to use O rings.

Jo
Enjoyment is more important than achievement.

Offline Jasonb

  • Full Member
  • *****
  • Posts: 9463
  • Surrey, UK
Re: hit e mis engine
« Reply #2 on: June 08, 2021, 05:14:56 PM »
If you are using red O Rings then they are not the best material for hit & miss engines, OK for steam. You need to look for Viton rings, these work well in a honed bore.

https://www.ebay.it/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=viton&_sacat=0&LH_TitleDesc=0&_odkw=vitone+passo+rapido&_osacat=0

Offline paolo1959

  • Full Member
  • ****
  • Posts: 24
Re: hit e mis engine
« Reply #3 on: June 08, 2021, 10:40:41 PM »
Thanks so much for the advice.
i am looking for a shop that sells piston rings.
the problem of the cylinder liners (but it can be my fussiness)
and that with a common lathe it is not possible to have an appropriate finish.
and certainly the functioning of the engine even with only an o ring seems to improve the finish but if you measure it you can see that it is not necessarily perfectly round and perfectly cylindrical.
live to save lives

Offline morane86

  • Jr. member
  • **
  • Posts: 1
Re: hit e mis engine
« Reply #4 on: August 08, 2021, 11:07:25 PM »
Hello Paolo, it is possible to find here. Check on Ebay.it item number 170930945418.

   

 
Piston Rings Ø 12 - 30 mm (0.472 - 1.181 in)
État :Neuf

Offline paolo1959

  • Full Member
  • ****
  • Posts: 24
Re: hit e mis engine
« Reply #5 on: August 09, 2021, 09:23:23 PM »
Thanks so much for your help !!!! :cartwheel:
live to save lives

Offline Admiral_dk

  • Full Member
  • *****
  • Posts: 3752
  • Søften - Denmark
Re: hit e mis engine
« Reply #6 on: August 10, 2021, 12:21:06 PM »
That eBay shop do sell some very nice spareparts - pistons, rings etc. - and a number of them will be useful for our purpose.

You can use your local eBay and search 170930945418 - great for those who don't feel like making them.

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal