Whiteside router bits--does size really matter?

[wood_newbie]

Okay, you can call me anal, but what would you guys consider acceptable tolerance between a router bit's stated cutting diameter and its actual cutting diameter?

I just bought a Whiteside spiral upcut bit, a 1/2" shank with a 1/2" cutting diameter. This would normally have been a $50 bit, but all Whitesides are 15% off at Hartville Tool through the end of the month.

Pretty little &^%$er, she is, all bright and shiny with her razor-sharp curves ready to tear at a man's heart...

So I chuck 'er up (collet 'er up?), and rout a nice little test mortise. Only to find out...she's undersized by .006. That's right...she's .494, not .500. My Starrett dial calipers say so, and they cost a whole lot more than the bit, so I gotta believe them, you know?

I know this is wood, and not metal, and I'm not performing brain surgery with the bit. But I would have thought, especially for Whiteside, that it would have been out by, at most, about +/- .002 or so.

Any thoughts?

[Frank K.]

Go to

and click on CONTACT US. They will answer in a couple of days.

Frank

[Vic Baron]

Considering that is less than 1/128" - I wouldn't concern myself. The wood will change size more than that daily. IMHO, in woodworking - about 1/16" is within tolerance.

Just MHO -

[Leon]

Seriously, what are you going to fit into a 1/2" grove? Not plywood. If you do find something or cut something to exactly 1/2" to fit into the grove simply sand the edges that go in a touch and it'll go right in. Plus, try milling 20 or 30 feet and then remeasure. You will probably find that it is even smaller.

[no(SPAM)vasys]

What type of wood did you use for the test? For .006 I'm wondering if the wood compressed while routing and then expanded once the bit passed.

Try mic'ing the bit.

[CW]

Horseshit. Ever try to fit a 3/4" shelf into a 11/16" dado?

[CW]

He did. Read it again.

[no(SPAM)vasys]

I read it again:

"So I chuck 'er up (collet 'er up?), and rout a nice little test mortise. Only to find out...she's undersized by .006. That's right...she's .494, not .500. My Starrett dial calipers say so,"

I read it as he measured the mortise.

[David]

And the winner...in this corner...wearing the...well who cares?...is...

Jack Novak

The OP mic'd the mortise; not the bit.

dave

[Robatoy]

You're anal.

I have several bits, some high-end, and the shafts measure all over the place ± .006. I have one bit which requires me to drive a steel wedge into a collet gap to open it up enough for it go in. That's a $285.00 insert bit. My experience has been that they're all over the map.

[Toller]

I bought a spiral bit from MLCS to use with my existing box joint jig. The craftsman straight bit gave too much tear out. With the MLCS bit my joints didn't fit. Turns out the craftsman bit was

0.500, and the MLCS was 0.485. I complained to MLCS and they told me to return it for credit less a handling charge, since a 0.015 error was within tolerances. I never bought from MLCS; I wish they would stop sending me their catalogs.

[CW]

[George]

More important, consider that after you rout the first inch or so that bit will have expanded say ... .006 from the heat, and we all know that you can trim a tight tenon easier than you can add to a loose one.

Worry about the bit when you can cut your tenons to .006 tolerance.

Oh yes, put the goddamn Starrett in the drawer and learn to use a rule or tape.

[Leon]

Not to mention that they stay sharper and hold up better than carbide tipped. I was plunge cutting 3/8" wide, 3/8" deep and 1/5" long slots through 3/8" thick Ipe typically 200 at a time. After 400 cuts the carbide bits were toast. After 600 the end mill bits still looked and cut like brand new compared to the carbide bit. I was using 4 flute HSS end mill bits.

[wood_newbie]

Sounds like a good idea...thanks you guys.

I must say, though, I'm unfamiliar with what an end mill actually is. It sounds like something more suited for drill press speeds, am I correct? (I don't want to end up like the guy that put a rosette cutter on his router, then through his aorta...)

[Morris Dovey]

I've also had good experiences using end mills. I recently got a batch of standard length 3-flute center cutting carbide mills from KBC Tools

catalog #1-330-008 and #1-330-016) and really like 'em.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[David]

Dave

[wood_newbie]

I work mainly with cherry, which is to say "I burn mainly with cherry." Think I would have any problems with burning on a 4-fluter? I would probably have problems lining up a 3-fluter, and I so far haven't found a 2-fluter.

Also, what kind of RPM should I run something like that at? (I believe my router goes 8,000 to 25,000).

[Morris Dovey]

I've been running my 3-flute bits at 15,000 - 16,000 RPM and feeding at 90 inch/minute (1-1/2 inch/second). Burning is as much controlled by feed rate as by rotation speed.

With a hand-held router (I'm cutting with CNC router which allows me to control both feed and speed) you'll benefit from practicing on scrap to get a feel for feeding at a rate that doesn't burn. Remember that it's the chips - much more than the airflow - that carry away the heat.

-- Morris Dovey DeSoto Solar DeSoto, Iowa USA

[Art Greenberg]

Morris,

Looking at that catalog, I found the parts by name on page 167. Where is the first part of the part number (1-330)?

And, what do you do for a collet for the 1/8-inch cutter (and for all of the cutters that aren't 1/4 or 1/2 inch dia.)?

TIA.