bazhart
Barcelona
- Joined
- 20 May 2009
- Messages
- 1,343
These are chatter marks where the rings has in the first ever running touched a few high spots and bounced on its way up and down.
Interpretation of markings is important and every mark must have some depth - but in that case all the cylinders are scored all the way round in an angles plane where you see the honing marks - which are (if you want to be awkward) scores.
The interpretation however of "bore scoring" is different - being deep grooves cut into the surface and not insignificantly microscopically polished areas that were originally minutely high spots where the ring touched those small high spots a little harder when first run and because the load then per unit area is high - managed to polish them down a little to create an even more round bore and better ring to bore fit, higher compression and less blow by - but due to the highly polished nature of Nikasil on reflection - marks the bore where the running in took place.
Baz.
Interpretation of markings is important and every mark must have some depth - but in that case all the cylinders are scored all the way round in an angles plane where you see the honing marks - which are (if you want to be awkward) scores.
The interpretation however of "bore scoring" is different - being deep grooves cut into the surface and not insignificantly microscopically polished areas that were originally minutely high spots where the ring touched those small high spots a little harder when first run and because the load then per unit area is high - managed to polish them down a little to create an even more round bore and better ring to bore fit, higher compression and less blow by - but due to the highly polished nature of Nikasil on reflection - marks the bore where the running in took place.
Baz.