Need Help!- tooling for a novice...

[shaun]

I have always wanted to learn how to run a lathe and milling machine. I finally have access to a manual knee mill, but there isn't anyone there that can give me guidance (I think the guy uses it as a drill press)...

My first 'project' was to take saw cut aluminum 1-3/4" round bar and face it on both ends yielding parallel ends and 'close' to the same height (2"). All the tooling is random. I did several pieces with an end mill that wasn't carbide and got ok surface finish, but the cutter clogged and needed a very slow feed rate. The next time I got an end mill with removable carbide inserts from the 'pile'. This tool cut great, but seemed to 'dig' in when either entering or leaving the work leaving a bad surface finish.

What end mill should I buy (and where from) for this type operation?

[78nova]

I use solid carbide SKI-CARB End Mills from Fullerton Tool for Aluminum milling and an A-Symmetric Solid Carbide End Mill from Hanita for steel. A high shear positive rake carbide insert cutter will also work and with any tool the right depth of cut, corner radius, feed & speed needs to be considered.

You stated you were digging into the work piece on entry and exit. try a shallower depth of cut and leave .010 to .020 for a finish pass to improve the finish. Make sure your work piece is solidly held and that your work head and table are both locked in place.

I am not much of a manual machinist so I do not know the workings of a knee mill to give you better operating advice. I run a 5-Axis Okuma MC60H CNC Horizontal Mill with a 100 tool capacity. 5000 max rpm.

Milling is milling. The tool does not care or know what machine it is being used in. Hope this helps some.

Kenny

[Fegenbush]

I don't know if tooling is the issue here. Feeds and speeds, as well as a light cutting oil are important for working with aluminum. If you have a decent endmill available at the shop and let us know the size, we can recommend a procedure to produce quality results. Setup is also important when dealing with short round pieces like you described. How are you holding the piece?

[ImanCarrot]

Remember the difference between Conventional Cutting and Climb Cutting

Here: right down the bottom of the page:

http://en.wikipedia.org/wiki/Milling_cutter