As per post below - made a conrod for a 1.5cc model engine and this is how it ended up - with only ever a few pops and maybe a few multiple rotations - but - no running.
Total time in service would be equivalent to around a half minute.
As you can see it has galled badly in the extreme, even left the crankpin in such a rough state you could use it for a file ! A black mess of what was probably Ti dust was inside the engine, but thankfully washed out without any damage to other componentry.
When a conventional alloy conrod was made the engine fired and ran within a few flicks, but the friction from what was happening here obviously denied it the ability to start.
So - what seemed like a good idea at the time - wasn't. !!
Obviously if a nice bronze bearing surface was inlaid both ends of the Ti rod, then that would work very nicely - but for now an alloy one serves the purpose as it has in many thousands of these little motors.
Hopefully this might help someone that is thinking along these lines - for me a lesson learnt - but that's what I made it for in the first place to learn a bit more about this "miracle" metal.
Ed
Photo of the oval crankpin end of the rod and galling on the right hand end of the pin.
Total time in service would be equivalent to around a half minute.
As you can see it has galled badly in the extreme, even left the crankpin in such a rough state you could use it for a file ! A black mess of what was probably Ti dust was inside the engine, but thankfully washed out without any damage to other componentry.
When a conventional alloy conrod was made the engine fired and ran within a few flicks, but the friction from what was happening here obviously denied it the ability to start.
So - what seemed like a good idea at the time - wasn't. !!
Obviously if a nice bronze bearing surface was inlaid both ends of the Ti rod, then that would work very nicely - but for now an alloy one serves the purpose as it has in many thousands of these little motors.
Hopefully this might help someone that is thinking along these lines - for me a lesson learnt - but that's what I made it for in the first place to learn a bit more about this "miracle" metal.
Ed
Photo of the oval crankpin end of the rod and galling on the right hand end of the pin.