Lapping It Up: Setting up for precision hand lapping

In which we learn about making and using cast iron laps and diamond slurry to achieve high finish and high accuracy surfaces in hardened tool steel.  And have fun doing it.

Robin Renzetti:  ‪@ROBRENZ‬ on YT and Instagram: robinrenzetti

Tom Lipton:  ‪@oxtoolco‬ on YT and Instagram: oxtools

Adam Balogh:  ‪@laneymachinetechclassroom‬ on YT and Instagram: laneymachinetech

Referenced videos:

Tom Lipton: Making Flat lapping plates 1 - Making flat lapping plates 1
Tom Lipton: Making Flat lapping plates 2 - Making flat lapping plates 2
Tom Lipton: Making Flat lapping plates 3 - Making Flat lapping plates 3

Robin Renzetti on the PFG Live, on lapping:  PFG IG Live 2022 0410 - Robin Renzett...

Adam Balogh on the PFG Live, on lapping:  PFG Live 2023-0115: Lapping with Adam

McMaster-Carr:
The Cast Iron plates - https://www.mcmaster.com/8588T23/
Hyprez Diamond Lapping Slurry, 3 micron:  https://www.mcmaster.com/4857A47/

---
ERRATA:

Robin Renzetti (‪@ROBRENZ‬ ) makes a very good point:  

"Remember that the straight band only shows "straightness" not flatness. You must align the bands a second time 90° to the first to access straightness in that direction to determine "flatness".

Only one reading is like using a repeat o meter on a surface plate oriented parallel to one side only. The flat is showing all the information in one orientation but curvature 90° to the bands registers as variation in band spacing which is not easily discernible by the human eye."

Thank you, Robin!!

---
Links for products/designs mentioned are at pfg.gg/links

Follow me on Instagram at "spencer_webb_nh".

("PFG Stones®" is a registered trademark of Kinetic Precision)