Love it!

 

great way to take up about 6-8 thousandths in diameter.

From what this machinist learned in school, (never done knurling on a piston, but have on a small shaft on a manual lathe), it raises the metal inside the knurl AND actually is more likely to increase the strength of the metal than fatigue it if done properly. Very little if any burrs will be raised, but some minor lapping (sanding) to fine tune the knurl easily can take car of that.

I can imagine it would allow for MUCH better lubrication.

 

Would like to see a pic of your air powered knurling machine Ivan...sorry lol I found the pic very cool!

Nice post.

 

here's someone elses writeup:

http://www.pbase.com/stealthfti/image/53355694

 

thats it the red machine in pic the air is just to putt preshure on knurlling wheel

Theese engines are getting kms putt on them the first knurlled piston engine has over 100000kms on it since and no piston slap and there are 30 + more out there that are racking up kms and no problems to report. The only downside is takes a long time to breakin about 3000kms customers have noticed 25-28 mpg after 3000kms or more jumps up to 30-34 mpg takes abitt to losen up but still no slap on any of them or any ishues