View Full Version : Couple of Questions

08-26-2003, 06:45 PM
Hi all, first off ... this site rocks!! I've been just taking in this wealth of knowledge out here, and what a big help you all have been ( with out even knowing ).

I have a new mill, planning on going cnc very soon.. and just out of experience, with 5XXX and 6XXX series aluminum, what have any of you found gives the better finish result ??
I've found so far that 4 flute @ 2500 rpm seems to work the nicest, but I'm leary of smoking the bit.

Also I do plan on going cnc very soon, have any new kits come out recently that are worth looking into, or that someone else has just got, and likes the package ?? I've been looking at Stepperworld.com, for a kit..... any feedback on these ??

One last one..... ( I know I said a couple ).... Notching out say 1" dia. O.D. steel tubing, does anyone know the name of the end mills that can be used for " fishmouthing " the end of the pipe/tube to create perfect joins for welding ?? Closest I've found is a 1" roughing ticn milling bit.... any suggestions ??

thanks in advance!!


08-26-2003, 06:58 PM

You didn't say what size end mill you are using, so the speed and feed thing is hard to say.

5000 series aluminum is fairly soft. It is not normally used for machined parts per say. 6000 series is harder, so it will normally finish better. and 6061 is more commonly used that 6063 for machined parts.

For fish mouthing a common hole saw will work quite well. Or you can get "rotabroach" mills, a high dollar hole saw. Both Hougen and Jancey make their own versions.

08-26-2003, 07:10 PM
I've found so far that 4 flute @ 2500 rpm seems to work the nicest, but I'm leary of smoking the bit

Smoking is bad for you, besides, how you gonna keep that sucker lit?? :eek:

More info on the tooling you're using. Dia? Material?

FYI, I run between 600 and 1200 sfpm on alum for HSS and Carbide.


08-26-2003, 07:24 PM
I am thinking the stepperworld kits are good for wood routers and shirline and taig conversions. I am not sure they would be good for a larger mill.


08-26-2003, 10:31 PM
oh, yeah specs on it would help huh ? ....sorry long day...
It's a Speedway Series Mill, from harbor freight. It's rated at 4/5ths of a hp. It has 2spds, and 0 to 2500 rpm variable speed adj. Nice solid little unit, fairly accurate, about as good as it gets for the pricetag. I've had up to a 3/4 " end mill 4 flute running nice and cleanly through .250 depth in a single pass, with no problems what so ever. It takes a R8 collet with a jt33 taper.

The stuff I've been working with the most has been some 1/4 and 3/8 " thick plate 6061....and more recently .125 thick aluminum plates.
hope this answers some questions...