Fly cutter or indexing mill?

It looks like end-mill followed by a fly-cutter for no more than 0.002". At least that is cheap :-)

Reply to
Michael Koblic
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Copolymers and alloys are two different things.

- Polycarbonate is a homopolymer-- comes from a single monomer linked together (polymerized)

- ABS is a copolymer-- it comes from two differeny monomers polymerized

- You can alloy ABS with Polycarbonate and get something like this:

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Best regards, Spehro Pefhany

Reply to
Spehro Pefhany

Thanks, Spehro. Curious, I Googled "plastic alloy," hoping that I might clear it up in my mind quickly, but I got over 28,000 hits and quickly gave up. d8-)

-- Ed Huntress

Reply to
Ed Huntress

In plastics "alloy" is just puffery for a blend. It doesn't express the same molecular principles as alloying in metals. The term is used because it sounds so much beefier than "blend". Like that epoxy product that is sold with "weld" in the name, to impress the ignorant who want to believe, or saying a fill-in-the-blank polymer material is "stronger than steel".

Reply to
Richard J Kinch

OK, thanks, Richard.

-- Ed Huntress

Reply to
Ed Huntress

The plastic gears in the 150 Lb Chinese mini-mill are definitely NOT any special plastic, but a crummy nylon-like material. People have told me that you can break the gears by twisting the spindle forcefully with your bare hand. They are also not a planetary set, so one tooth is generally carrying all the load.

Jon

Reply to
Jon Elson

I guess the next Chinese innovation will be plastic carbide toolholders.

Reply to
Ignoramus18994

Too bad. Once they're going to the trouble to make injection-molded gears, they'd might as well be good ones. And the high-performance resins that are available today shouldn't add much cost to something like a mini-mill.

-- Ed Huntress

Reply to
Ed Huntress

Plain spur gears, about 1/4" wide. You could not break them spinning it by hand though. I've broken mine once, but it was definitely my fault.

The poor design is locating the "fuse" in a relatively inaccessible part of the headstock. If I used mine more often, I'd convert to metal gears and a belt drive.

Reply to
RB

I don't think the dictionaries have been updated for plastics or polywhatevers. I was tweaking you for not following the definition I grew up with.

Wes

Reply to
Wes

As a couple of people have commented, it may well be nothing but industry jargon. They hired me for that job because I knew gears, not plastics, and I don't really know anything more about them now than I did then.

-- Ed Huntress

Reply to
Ed Huntress

I have a feeling that plastics is a bit magic just like metals, alloys of metal and heat treatments.

Morphing of terms to deal with new techology seems to be a fad that has caught on. At least we deal with new words or the re-definition of old words a bit better than the French. I'd hate to see what the French would call an 'alloy' of plastic.

Wes

Reply to
Wes

aught on. =A0At

The French have too much bitter experience with "plastique".

TV and advertising writers make up the words, and who is going to stop them?

jw

Reply to
Jim Wilkins

That looks like a nice one, too. Two inches and three inserts should give a nice clean surface. I may have to pick one of these up and try it out myself. Nice price, too.

My only concern with it is that it uses a morse taper while the one I use is a full drawbar affair. No chance of it ever coming loose in the spindle.

-Frank

Reply to
Frank J Warner

Don't get me started on "billet."

Google says it's "en alliage de plastique." Everything sounds better in French. Even snails.

-- Ed Huntress

Reply to
Ed Huntress

I have not even considered that it would not have a draw bar thread at the end! Something to check with Busy Bee I guess. Also *what* thread. Some of them are 3/8-16 some are M12. Mine is the former.

I figured that 2" should be fine for the mini-mill: People use a 2" boring head which is inherently more un-balanced affair.

Reply to
Michael Koblic

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