Hi Dieter
Can you please provide dimensions of the spindle nose, eg. taper start and end diameters, looks a lot like an Orac spindle nose but I believe it is slightly bigger.
xpylonracer
Richard
The Hitachi unit you linked to is not suitable for a 240v 1PH supply, the spec sheet says 3 phase input and also it is rated for 3kW motor so oversized for your use. I believe Hitachi are a reliable make so not necessary to use a higher rated VFD than the motor plated size.
This topic...
Rick
Check to make sure you haven't got a backlash problem on the X axis as that could cause loss of travel into the work after a toolchange if the
grooving tool moved out from the job to provide clearance before making the groove cut.
xpylonracer
Mike
The machine was an Emco 5 cnc lathe on which you can adjust the tension on the ballscrew by turning a nut, reducing the backlash gave improved results.
xpylonracer
Kevork
Is the engine shown your own design ? looks like it is for tethered car model, very strong looking design, I like how you design the starter flywheel via the crankpin.
Xpylonracer
Sometimes if the piston diameter is too large, so does not have enough room for expansion when running, there will be evidence of the tightness on the piston surface as you describe.
Best clean the damaged areas and run again to see if it appears again, after a few run and strip to clean...
Checking the noise level from a running engine is best done over grass in an open area, there is just too much noise reflection inside a garage.
xpylonracer