Machining Hardcoat Anodize ??

C

capecod

Plastic

Joined

May 4, 2008

Location

Carver,Ma

• Sep 8, 2009

• #1

I have 4 parts made from 7075 aluminum. One surface was supposed to be masked from hardcoat anodize. Didn't happen. Anyway the fix at this point is to flycut clean this surface. (dimension not critical- at all).
The only thing critical is all 4 have to be the same size.

What is the best way to do this. Light cuts, heavy cut etc.

My best guess tells me to put in "old" inserts and take @ .010 off. then change to fresh inserts and take a light finish cut.

What do the people that know and aren't guessing think?

 

L

Limy Sami

Diamond

Joined

Jan 7, 2007

Location

Norfolk, UK

• Sep 8, 2009

• #2

If you keep the speed down it's nowhere near as nasty as many will hve you believe.

As you've only 4 to do, nothing critical or clever, for a fly cutter you can use HSS, run at steel speed to get rid of the anodise, then sharpen / hone cutter then run at ally speed.


FWIW
Steel 100'/min

Ally 300'/min.

 

D

dsergison

Diamond

Joined

Oct 23, 2003

Location

East Peoria, IL, USA

• Sep 8, 2009

• #3

just pretends it's not there and cut. sure it's hard, but very thin. get under it a bit and it be broken up by the advancing chip and you may not even notice too much wear.

 

C

capecod

Plastic

Joined

May 4, 2008

Location

Carver,Ma

• Sep 8, 2009

• #4

Thanks

That was quick... thanks guys

 

IAMATT

Stainless

Joined

Aug 3, 2009

Location

LAS VEGAS, NV

• Sep 8, 2009

• #5

All I can say is go 3 times deeper than the plating. Most plating is about .0015-.003 so take .01 off and you should be good at almost any speed. Hard anodizing is tough but the base metal is not (aluminum)

 

machine1medic

Titanium

Joined

Jul 1, 2006

Location

Clover Hill district, WI

• Sep 8, 2009

• #6

Wd 40

WD 40 , is the concubine that aluminum Loves.

.007 to peel the crust off, the .003 to finish at twice the RPM.
Spray into the fly-cutter as it travels so the back-side of the cut
gets some too.

In the 80's we had to give a 32 finish for heatsinks for SCR bricks.
( SCR's for all three phases in one brick ) was my understanding.

M1M

 

Forrest Addy

Diamond

Joined

Dec 20, 2000

Location

Bremerton WA USA

• Sep 8, 2009

• #7

I didn't see carbide mentioned for cutting edges so here it is. HSS will poop out fairly quickly. Hard anodize in 0.002" or so of a single aluminum oxide crystal.

 

machine1medic

Titanium

Joined

Jul 1, 2006

Location

Clover Hill district, WI

• Sep 8, 2009

• #8

Forrest Addy said:

Hard anodize is 0.002" or so of a single aluminum oxide crystal.

Click to expand...

I wonder if any-one ever put those stunning micriscopic pics of
a hard-coat anodized forrest on the net?

After die-ing it's breath-taking.

m1m

 

C

capecod

Plastic

Joined

May 4, 2008

Location

Carver,Ma

• Sep 8, 2009

• #9

Sorry ... yes 4-flute carbide insert shellmill CNC w/ flood coolant

 

PixMan

Diamond

Joined

Jan 30, 2007

Location

Central MA USA

• Sep 8, 2009

• #10

With hard-coated 7075 make sure you use TiCN coated inserts if at all possible. Uncoated carbide won't last much longer than HSS.