Hello Everyone,
I have a new 1440 lathe, which cuts a taper when using carbide tooling. I am using TNMG carbide inserts with a 0.8mm tip radius. I am locking the cross slide and compound slides when making the cut using power feed. I checked with a fresh insert and took light cuts of about 0.1mm and it is still doing it. The taper is 0.02mm over 70mm. If I use a nice sharp HSS tool I get virtually no taper. I thought that it may be the spindle bearings but I get a nice shiny finish and when I push and pull on the bar the chuck only deflects about 0.005mm. I am using a 30mm bar for the test.
My question is this normal for carbide tools to push a 30mm bar that much that I get a taper or do I have a problem somewhere?
I have a new 1440 lathe, which cuts a taper when using carbide tooling. I am using TNMG carbide inserts with a 0.8mm tip radius. I am locking the cross slide and compound slides when making the cut using power feed. I checked with a fresh insert and took light cuts of about 0.1mm and it is still doing it. The taper is 0.02mm over 70mm. If I use a nice sharp HSS tool I get virtually no taper. I thought that it may be the spindle bearings but I get a nice shiny finish and when I push and pull on the bar the chuck only deflects about 0.005mm. I am using a 30mm bar for the test.
My question is this normal for carbide tools to push a 30mm bar that much that I get a taper or do I have a problem somewhere?
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