You need inserts for interrupted cuts for the lathe and mill be it's nature delivers the same type of cut – you don't get that sort of info with the Chinese cheapies.

I use 0.4mm dia points if you are using 0.2mm that might be why.

I would tend to say no, you are doing very nicely with the kit you already have. Bargains do come up on ebay from time to time, I have some resharpened solid carbide endmills which would have cost 4 times what I paid when new. I also bought some second hand 6mm solid carbide endmills very cheaply, and when they arrived, I quickly bought the rest of the stock before somebody beat me to it. They get used for rough jobs and still keep cutting.

Get used to putting a soft landing pad under the cutter when loosening the collet, it saves those pesky chips.

Hi Iain.

I bought a large amount of carbide cutters some time ago. These are top or good quality ones . I did as you say make a boo boo with one of them by dropping it from memory. Or coming into the work to fast. See pic.

But when treated with respect they are quite an amazing cutter to have in your arsenal. Just yesterday i was cutting steel for some vice holding clamps & the ease of cut & finish was very good.

Steve.

Your post makes it sound like you are loosening collets in a vertical mill and allowing the tool to fall working edge first onto the material/vice/machine below it. Not a good idea but i might just be mis-interpreting what you wrote.

Regarding chipping of carbide in the lathe, the only issues I have had with unexpectedly premature destruction of the carbide tip is if the tip is pushed in the wrong direction by manually moving the chuck when there is subsequent contact with the tips or if the part is rotated in reverse and not noticed until too late. If this happens it takes next to no effort to chip the edge and may not be noticed until it is used the correct way round and falls apart. The last one I chipped like this I needed to invert the tool I was using to get into an odd position on the right and working away from the chuck and forgot to reverse the spindle.

Martin C

Guess what guys cutting tools are brittle.

Tony

At high rpm the velocity vector will always be close to vertically downwards or in a direction where the cutting edge has support behind it unless you drive the insert towards the workpiece at silly fast rates. At low rpm the velocity vector can go more towards horizontal which inserts are not designed to handle. A zero rpm will always be a horizontal velocity vector and there is then no support behind the cutting edge on a lot of inserts.

Martin C

Actually not much of their turning stuff, CCMT is usually Kennametal where you can pick up a box for around £10 (5 in their boxes) and the others mostly from APT about £3 each as they do more shapes and 0.2mm radius which I mostly use on both **Mt and **GT.

I do use ARC's milling inserts and can't tell any difference between results from them and Korloy but both are considerably better than really cheap BG that I have tried same for BG's turning inserts.

On the Milling front I do use ARC's Premium HSS in 10 and 12mm sizes mostly as well as a few of their premium Carbide milling cutters. Small HSS is often 3-flute "disposables" by Hertel as the price is right and 6mm and under carbide cutters for the CNC mostly come from APT again as they do types that ARC don't though I do have some ARC ones as well as New Century which are from YG-1's china factory rather than the main Korean one.