round flutes in round stock

[mbond]

Hi I am working on what I though was going to be a simple project, but I'm stuck on one part

The main body of the work is 1/2" round stock aluminum. I need to add rounded flutes on the outside of the cylinder at 60 degree intervals. I made a test piece with a rotary table and a 3/8th" end mill, but I can only cut the 1" or so length of the end mill and I need 3-4 inches of fluted stock.

Does anyone have any suggestions as to how I can make these cuts?

probably I need to turn the whole thing 90 degrees and mill along the length of the piece, but how do I get the appropriate radius from an end mill?

 

[YYCHM]

probably I need to turn the whole thing 90 degrees and mill along the length of the piece, but how do I get the appropriate radius from an end mill?

Ball Nose End Mill....

0.0781"Øx 0.25" LOC x 1.5" OAL- Ballnose - TiAlN Coated - G4 4F Carbide End Mill

0.0781"Ø x 0.25" LOC x 1.5" OAL- Ballnose - TiAlN Coated - G4 4F Carbide End Mill

castelartool.com

 

[DavidR8]

Are you trying to make something that looks like a fluted column?
If so a ball nose end mill will do the trick.

 

[Aliva]

Here's a 3/8 x 3" end mill. Just fill in your requirements

Carbide End Mills | Made in Canada Skookum Brand | Online Supply

Skookum Brand solid carbide end mills are Made in Canada to the highest industrial machining standards.

onlinesupply.ca

 

[Dabbler]

You could also try a 4" long annular cutter. The annular cutter might be faster, but there is the worry about chatter and deflection... There's a rotary table option. You can spin it off centre in your lathe and drill/bore it out. Many ways to skin this cat.

 

[mbond]

thanks

For these ball nose end mills, none of them seem to document the radius of the hemispherical portion. Is it always half the shank?

I think it is better to try cutting this way than to use a long cutter.

 

[thestelster]

thanks

For these ball nose end mills, none of them seem to document the radius of the hemispherical portion. Is it always half the shank?

I think it is better to try cutting this way than to use a long cutter.

Generally yes, though some of the smaller ball endmills are also available in a larger shank. I.e. 1/4" ball endmill with 3/8" shank.

 

[Susquatch]

Generally yes, though some of the smaller ball endmills are also available in a larger shank. I.e. 1/4" ball endmill with 3/8" shank.

Don't those ones have a smaller neck (say 1/4" or less in the case you mention)?

 

[Upnorth]

thanks

For these ball nose end mills, none of them seem to document the radius of the hemispherical portion. Is it always half the shank?

I think it is better to try cutting this way than to use a long cutter.

A ball end mill has a constant radius. If you want a radius with a flat bottom that is a bull nose end mill. Available in tons of configurations.

 

[thestelster]

Don't those ones have a smaller neck (say 1/4" or less in the case you mention)?

Neck?

 

[thestelster]

A ball end mill has a constant radius. If you want a radius with a flat bottom that is a bull nose end mill. Available in tons of configurations.

I never knew that! I'll have to check them out. Learn something new every day!

 

[Susquatch]

Neck?

Yes, neck. As in:

The neck can be long or short. It's the part that connects the fluted section to the shank. Not to confused with the shoulder.