Hi all, I've been recently trying to get to grips with threading on my Denford Orac machine it's not something I've done alot of on the cnc.
The problem I am having is that the thread is not cutting deep enough on an internal thread for the values I am entering into the threading wizard v1.17.
I have adjusted the backlash to zero in software (only 0.035mm in Z and oh my 0.09 in X)
I have adjusted the v point tool offsets (Glanz internal insert tool) so the point just touches the internal bore at 44.67mm
I require a thread pitch of 1.25mm and my math works the depth out using pitch * 0.866025 for crest to crest thread.
So in the wizard X start of 44.67. and the X end value of 45.7525. First pass depth of 0.15 which works out at 20 passes.
The lathe is started and threading commences, all sounds good and small swarfs of aluminium on each pass.
Removed billet and inspect thread, thread is cleanly cut, tracked perfect but the internal crest has a flat of approx 0.5-0.8mm on it.
I've done this thread several times and they all come out the same.
Is my maths wrong or is there something I have overlooked in software settings.
I know I can bodge the figures to "get in right" but I will be doing a large amount of threads at differing diameters so I am trying get the sums right first.
Any advice helpful.