Lathe - Boring Speeds and Feeds
First off just want to say major thanks to Mr. Gerfanov for the wonderful tool he has created in HSMAdvisor. I have a a few newer (2012 and up) Haas machines and the speeds/feeds and WOC/DOC that have been recommended on the mills have been dead on in aluminum, A2, D2, 1018 and A36 HRS and increased my productivity by multiples.
The question I have is regarding the lathe feeds and speeds. I have a small Haas CNC Lathe (TL1) and am having difficulty with the recommended feeds and speeds, especially regarding boring operations.
I typically run small (3/16", 1/4") boring bars that are carbide with a brazed on tip with coated carbide inserts. I have attached a screenshot of the recommended feed and speed for a 1/4" bar that I tried to run and had chatter and visible deflection from the first pass in A2 tool steel. I am inexperienced on the lathe and can not figure out how I am supposed to come even close to the numbers the calculator presents. I have found success at approximately 75 SFM, 0.00808 FPR, and 0.005 DOC. This is 1/3 the DOC and less than 1/4 the surface speed the calc has recommended. Is this bar just too long and not being compensated for in the calculator properly?
I have tried with a 0.2500 bar and 0.3750 bar and all of them chatter so bad I am lucky to not have broken one already (and these are $100+ bars, good quality tools). Is there a secret to the lathe side of HSMA I have not figured out?
Sorry about the book, I just looked for a long time and in the help and forums for someone with the same problem and couldn't find it, so I decided to create a detailed post explaining what I need.
Thanks in advance,