I need to engrave some anodized aluminum and I'm looking for suggestions
for a suitable cutter for vertical use in a mill.

I tried a pointy carbide burr from a Dremel and it didn't work too well,
leaving a ragged edge on one side. I tried a V grove router bit and it
also produced lousy results.

Looking around it seems that those Hermes engravers use a half round
pointed cutter. Thinking I might be able to grind one out of a
sacrificial drill bit shank.

I'm also not sure how fast I need to run them to get decent results.
Obviously I don't need a very deep cut, just a little through the
anodized layer, but I do need a pretty fine line, perhaps .020 - .030.

Thanks,

Pete C.

diamond bits in a high-rpm rotary tool (Dremel & likes) ?

rashid111 wrote:

diamond bits in a high-rpm rotary tool (Dremel & likes) ?

Unfortunately I need to do this engraving partly on a Bridgeport that
tops out at 2,700 RPM, due to the need to use a tilting dividing head
for some of the work (degree markings), and partly on a CNC mini-mill
(2,200 RPM) with a hacked together A axis to do the number engraving.

In case you're wondering why I don't do it all CNC, the dividing head is
too big for the mini-mill and the hacked together A axis which is direct
drive with a stepper will only give me about .9 degree resolution. The
dividing head will give me precise degree markings, and the CNC A axis
will give ok numbering since it won't matter if the number is a fraction
of a degree off as long as the line is correct.

Pete C.

I was having an awful time trying to get decent-looking v-carving
results. SOmeone had sent me a sample of a different cutter a while
back, and I dug it out - what a difference! I'd tried my own
D-cutters (1/2 cone, with relief), New Hermes ditto, all with less
than stellar results. The double ended cutter I NOW use comes from

is TiN coated, and does a great job in Al, brass, acrylic and wood,
at least for me.

I have no connection with the vendor, but just had to speak up.
/mark in BC Canada


Pete C. wrote:

I need to engrave some anodized aluminum and I'm looking for suggestions
for a suitable cutter for vertical use in a mill.

I tried a pointy carbide burr from a Dremel and it didn't work too well,
leaving a ragged edge on one side. I tried a V grove router bit and it
also produced lousy results.

Looking around it seems that those Hermes engravers use a half round
pointed cutter. Thinking I might be able to grind one out of a
sacrificial drill bit shank.

I'm also not sure how fast I need to run them to get decent results.
Obviously I don't need a very deep cut, just a little through the
anodized layer, but I do need a pretty fine line, perhaps .020 - .030.

Thanks,

Pete C.

"Pete C." wrote in message
...
I need to engrave some anodized aluminum and I'm looking for suggestions
for a suitable cutter for vertical use in a mill.

I tried a pointy carbide burr from a Dremel and it didn't work too well,
leaving a ragged edge on one side. I tried a V grove router bit and it
also produced lousy results.

Looking around it seems that those Hermes engravers use a half round
pointed cutter. Thinking I might be able to grind one out of a
sacrificial drill bit shank.

I'm also not sure how fast I need to run them to get decent results.
Obviously I don't need a very deep cut, just a little through the
anodized layer, but I do need a pretty fine line, perhaps .020 - .030.

Thanks,

Pete C.

Check with your tool supply house for a straight shank pantograph needle.
They are a spade type cutting device that cut to the point, so you can
regulate the depth of cut to control line width. They are made in both
HSS and carbide, so if you have much to do, use carbide to get around the
rapid tip wear. Be aware that they are almost impossible to sharpen by
hand, because you lose center almost instantly when you try. That makes
them cut poorly and not on center, so the line will be wider than you
desire. A cutter grinder is the way to go in this instance.

Speed? You don't have anywhere near enough, so you'll have to take it
slow. You should run such a cutter in the ten's of thousands of
RPM-----surface speed is almost 0 otherwise. You'll be able to accomplish
your mission----and burr free, but lubricate the cut well with kerosene or a
good tapping solution for aluminum------and feed slowly. It's very easy to
chip the point otherwise.

Harold

I did a 6" diameter platter for a bender and marked it with 360 degree
markings and numbered every 10 degrees with a rotary table on my BP. I
used a single point tool (not rotating) for the degree markings moving
from the outside in, this raised a small burr at the end which I later
stoned off. The numbers were done using standard punches and a small
fixture held in a collet and prevented from rotating by a pin which went
up through the small hole 5/16"? to the right of the quill. The metal
raised by the stamping was also later stoned off. It took about 2.5
hours IIRC.

Pete C. wrote:

rashid111 wrote:

diamond bits in a high-rpm rotary tool (Dremel & likes) ?


Unfortunately I need to do this engraving partly on a Bridgeport that
tops out at 2,700 RPM, due to the need to use a tilting dividing head
for some of the work (degree markings), and partly on a CNC mini-mill
(2,200 RPM) with a hacked together A axis to do the number engraving.

In case you're wondering why I don't do it all CNC, the dividing head is
too big for the mini-mill and the hacked together A axis which is direct
drive with a stepper will only give me about .9 degree resolution. The
dividing head will give me precise degree markings, and the CNC A axis
will give ok numbering since it won't matter if the number is a fraction
of a degree off as long as the line is correct.

Pete C.

On Sun, 04 Dec 2005 16:48:31 GMT, "Pete C."
wrote:

I need to engrave some anodized aluminum and I'm looking for suggestions
for a suitable cutter for vertical use in a mill.

I tried a pointy carbide burr from a Dremel and it didn't work too well,
leaving a ragged edge on one side. I tried a V grove router bit and it
also produced lousy results.

Looking around it seems that those Hermes engravers use a half round
pointed cutter. Thinking I might be able to grind one out of a
sacrificial drill bit shank.

I'm also not sure how fast I need to run them to get decent results.
Obviously I don't need a very deep cut, just a little through the
anodized layer, but I do need a pretty fine line, perhaps .020 - .030.

Thanks,

Pete C.

Pete, download the Gorton Pantograph manual from John Carrolls site,
its got a decent section on grinding single flute engraving cutters.
Pretty understandable. I posted the link last week. Use google for
the message. I dont have the link handy at the moment..(posting from
laptop out in the shop)

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

David Billington wrote:

I did a 6" diameter platter for a bender and marked it with 360 degree
markings and numbered every 10 degrees with a rotary table on my BP. I
used a single point tool (not rotating) for the degree markings moving
from the outside in, this raised a small burr at the end which I later
stoned off. The numbers were done using standard punches and a small
fixture held in a collet and prevented from rotating by a pin which went
up through the small hole 5/16"? to the right of the quill. The metal
raised by the stamping was also later stoned off. It took about 2.5
hours IIRC.

Unfortunately neither of those options will work. I can't stone off a
burr since that would also take off the anodizing and make a visual
mess. I can't use number stamps since I need to remove the anodizing
where the markings are so I'll have nice shiny silver markings on the
black anodize background.

Pete C.

Pete C. wrote:

Unfortunately neither of those options will work. I can't stone off a
burr since that would also take off the anodizing and make a visual
mess. I can't use number stamps since I need to remove the anodizing
where the markings are so I'll have nice shiny silver markings on the
black anodize background.

Pete C.

Maybe make the markings first, whether with a cutter or stamp, fill
them with paint or a similar type of resist, wipe the resist off the
high spots, then anodize?

John Martin

look into the Metalphoto process.
I have probably run a few acre of this stuff and its really easy. No
special gear needed just a kinda dark room and a couple trays of
chemistry.
You can make the art on your laser printer with vellum paper and the
accuracy will be very high
after you do the shot you just boil it for about 15 minutes
Then cut the part out. It will have a saphire hard anodization that will
last forever.