Maybe try some better inserts, When I first got a facemill (50mm) I got cheap inserts and it really struggled and the machine vibrated a lot. Changed them to Korloy and YG-! and it transformed the ability to cut. These are 0.8mm tip radius.

+1 for Jasons' suggestion of getting a better breed of insert.

The sharp edge on aluminium specific insets is, by reason of its slender geometry, inevitably somewhat weak. The continually repeating shock loads of a face mill give it a hard life.

Cutting stresses on steel are considerably greater than on aluminium so there is a good chance that the sharp edge will be rapidly battered off if the insert material is insufficiently strong. The made to be inexpensive inserts are likely to be made from a less costly carbide giving an edge that is strong enough to handle aluminium and its weaker alloys when used with care under appropriate conditions. But steel is asking too much of it.

Professional grade inserts are designed to stand up to production use in CNC machines which drive them hard enough that the shock loads in aluminium can be greater than those encountered on ordinary steels when used in our lighter machines. So they stand up pretty well when used on the wrong material. Some of the harder breeds of steel will faze them tho'.

As ever its a question of price / performance ratio. Leaving aside the uber cheap "probably junk" selections the less costly the insert the more care you have to take to stay firmly inside its safe operating region. So inexpensive aluminium ones should stay on aluminium and be used with care.

None of us are in any real position to definitively evaluate insert performance so its just a matter of common sense and appropriate use. In the "good(?) old" HSS days there was a certain commonality between home shop and industrial use / machinery so intelligent re-appraisal of industrial focused guidelines was easy and appropriate. Not so now where carbide use is generally focused on making more chips per day then most of us manage in a lifetime!

The uber cheap inserts are frequently just grabbed from a batch that failed quality control so its totally dependant on luck and statistics whether you get good ones, bad ones or something in between. No production user will risk inserts that don't have reliable performance statistics so iffy batches are binned on a regular basis. Up to Mr Carbide Scrappy whether the material is re-cycled or sold on for cheap inserts. Whatever is the best deal. Money talks.

Clive

The sharp inserts intended for aluminium will work very well with lighter cuts in steel, both for mills and lathes. The cheap ones have got far better in recent years and if you are happy to use them instead of the steel grades, then go for it. Small cuts will take more time, but will extend the tip life greatly The radius differences are only significant if you want a sharp corner, and the tiny bit left could be removed using an ordinary end mill.

Edited By old mart on 31/05/2022 17:48:41

Here is what I just received for a 40mm shoulder mill as advised by Walter agent for use with my benchtop mill(2hp) for aluminium & metal, cast iron etc. You can look up the details. I am still waiting for the cutter(4x inserts).
Cutter=F4042.B16.040.Z04.08. : 6077954 Milling Cutters Walter BLAXX/Xtra tec

Inserts:
-ADMT080308R-F56 WKP35S. : 5886208 Milling Inserts 10 (Walter BLAXX/Xtra tec)
ADHT0803PERG88WK10 : ADHT0803PERG88WK10