View Full Version : First Milling project.....need some help!

10-16-2007, 07:30 PM
I'm going to make a set of bullet mould blocks out of 2024 aluminum for my first test on the milling machine. (2" x 1.5" x 1.5") . When squaring the blocks would you guys use a flycutter or end mill?.. For those who like to use end mills what size would you use 1/2" ???...carbide or HSS, 3 flute or what?? I've seen it done primarily w/ an end mill. I'll probably use the flycutter when squaring the face on the mould blocks so I can scratch a few vent lines in the process.

What about some of the insert cutters for facing ?..... They look expensive to use. Can you get a better finish from these as compared to end mills. I've never used one so I have no idea.

Thanks for the help..........krems

10-16-2007, 07:54 PM
Flycutter. Have a look at these: http://youtube.com/results?search_query=flycutter&search=Search

10-16-2007, 08:05 PM
Flycutter for horizontal surfaces, end mill for vertical ones. I use a 3/4" one running fairly fast. Aluminum is easy stuff. Use WD40 or kerosene for lubricant (WD smells better).

Uncle O
10-16-2007, 08:09 PM
Use a flycutter if you have one, if not and you have an endmill, use that.
Either will get the job done, but a flycutter will get it done in one pass per side. Yes, the insert cutters are pricey, and they're not cheap to load.


10-16-2007, 08:20 PM
I generally square with a fly-cutter on aluminum. Very nice finish, just don't get in a big hurry. Depending on what you want, you can speed things up squaring with an EM and using it to side cut. Not much deflection on aluminum. For EMs in aluminum, I use 2 or 3 flute generally. 2 for finishing, generally HSS, and 3/4-1" at the flutes (3/4 shank in R8). A smaller 2 flute in HSS or carbide for pockets/slots. And 1/2" 3 flute carbide for roughing/hogging in the open (simply because I've got a bunch cheap and you can push them so fast it's scarry).

10-16-2007, 08:35 PM
I agree a fly cutter is just fine. the larger swing of the cutter will cut things flatter.

Dont be afraid to file an anomaly, I use a file all the time.

10-16-2007, 08:38 PM
I agree a fly cutter is just fine. the larger swing of the cutter will cut things flatter.

Dont be afraid to file an anomaly, I use a file all the time.

It will tell you what you need to know about tramming, too :) After using 3/16" end mills for a couple months I thought I'd set up for coving after making a 2.5" flycutter.

10-17-2007, 12:44 AM
I'm liking the flycutters for the horizontal flats. . Especially after watching the link that Dp posted on Youtube.

I'm sure I'll need both eventually. I'll get a 3/4" endmill for side cutting. When side cutting If i'm going to square both block halves together in the vise I'll need to sidecut 1.5" of aluminum. If I am using a 3/4 " endmill for this job what flute length should I get?. Can it be side cut in one pass or an I going to make multiple passes..........???..........newbie here...sorry!

Thanks for the help!..........Krems

10-17-2007, 04:15 AM
I have never used a flycutter and went straight to the insert style facemills. I have a 50mm and a 100mm ie 2" adn 4". The 4" is a Sandvik with 7 inserts.
Man does that thing throw some chips and gives a finish like glass on steel and ally.

My Bridgeport clone runs the 4" well but any larger and I think it might struggle.