Machined blade finish without having to polish?

[Ironman1]

Hi Guys,
I have been machining some custom knife blades on my vertical mill for a couple weeks now and have been having trouble getting a nice smooth finish.
I use a 3/8 ball nose end mill for my finish pass on the blade and I haven't been happy with how it turns out.
Has anyone here been able to get a smooth finish to their blades just machining them? Or am I just dreaming of being able to get away from having to polish the blades?

Really appreciate any advice/suggestions anyone has.

 

[Frank Niro]

Nathan the Machinist will probably get around to reading this. He will definitely have the answer for you. Frank

 

[leifjl]

Just curious, but why choose a ball mill to clean up flats?
Like Frank said, Nathan will probably have a good answer for you, but I'd say that a good satin finish can't be beat by a machined finish.

 

[Nathan the Machinist]

A good satin finish can't be beat by a machined finish. I've tried. The knife on the left is "as machined" and tumbled, the guy on the right was ground.

I documented the process with a WIP thread earlier in the year. These are the highlights:

The center of a ball endmill doesn't cut well, so unless you can angle your workpiece it is going to have that dragged-over-with-a-ballmill finish.

I think the best approach to get a good surface finish on a mill is to use the side of an endmill or use a facemill. But you can't beat grinding.

 

[Frank Niro]

And as well, doesn't he do great work !!! Frank

 

[AVigil]

Those pig stickers are just screaming to stab something.

 

[Don Hanson III]

It can be done on a mill, Nathan is the man!

 

[roblockwood]

A bull endmill works better, but I agree (as usual) with Nathan.. Youre best off either making an aesthetically pleasing machined finish that shows off the machining, or plan on getting it close enough that it doesn't take much work to clean it up manually.

Nathan, do you remachine the bevels post HT? Or are you taking it rather close pre-HT?

 

[NCCNC]

Hey ironman, e mail me at damianhhweller at gmail dot com, it will be worth your time. I am feeling giving this season.