[Cartierusm]

Howdy, I've no idea on how to sharpen endmills and such, nor do I want to learn or get the needed equipment. Sending them out costs almost as much as a new one. So I could use some simple input on the benefit or the difference of using tools with replaceable carbide inserts for milling on a Bridgeport and a CNC router that is rigid enough to cut aluminum. I will be mainly cutting aluminum but also steel at times.

Is the benefit of a tool with replaceable carbide insert is being able to just change an inexpensive insert to get a new sharp tool? Do you just throw away the insert or are they able to be sharpened? Do I follow the same rules when calculating RPMs, cutting speed and amount of cutting?

[DareBee]

If you are facing decent sized parts, a shellmill with inserts is an invaluble tool.
If you are talking about full depth center cutting tools, then you can not run your bridgport fast enough to utilize it effectively.
Either tool will not be suited for the router because it will not be rigid enough to handle the required chipload and extra cutting pressure.

Don't be fooled about insert prices, the good tools use inserts that are 8-15 bucks each.
As far as facing in a knee mill goes an cheap set of tools that use TPU inserts or a flycutter with a carbide tipped tool are the bare-bones - standard minimum requirement.
S & F are calculated the same using different numbers.

[Halfnutz]

Keep in mind most of the carbide insert type endmills are 1/2 inch or larger and these are fine for facing and finishing but too large for profiling on a small/medium sized router cutting out shapes in aluminum. I like 1/4 inch shaft 1/4 inch 2 flute upcut endmills. They are great for cutting out shapes in aluminum with router/gantry type machines and can be had for 12-14 dollars US. I have a 1 inch "lill hogger" with 3 inserts for facing that is great, but for cutting out aluminum I prefer the 1/4 inch endmills and just replace them after they dull.