3-flute and 5-flute measuring

Jun 04, 2015 29 Replies

Step one: Don't pay any attention to Jonnie Bonkers.

Mic the shank diameter.

Place shank in V-Block, put dial indicator tip on high spot of shank (center) and zero out indicator.

Move indicator to flute, measure high spot on flute, difference between shank and flute reading is radial value that value X 2 gives you the difference in diameter.

If needs be, check each flute to see what the run out may be.

snipped-for-privacy@aol.com fired this volley in news:56b29499-27f9-4d2a-8b2f- snipped-for-privacy@googlegroups.com:

Never have... and I don't even see references to him unless someone mentions or quotes him.

Did you have a particular V-block in mind?

If any one flute were more than half-a-tenth out, I would think it was a cheap Chinese cutter.

Lloyd

On Friday, June 19, 2015 at 2:40:41 AM UTC-7, Lloyd E. Sponenburgh wrote: snip

A precision ground V-Block would be my preference. Size depends upon the range of cutters you want to check.

Unless I missed something, we are talking about re-grinds so tolerance is up to the people and equipment doing the regrinds. Also .00005" seems a little tight for a regrind where most peoples tool holders are not that good.

If it is a cheap Chineese cutter I wouldn't even bother to re-grind since the base material itself is questionable at best.

Tom

snipped-for-privacy@aol.com fired this volley in news: snipped-for-privacy@googlegroups.com:

I have a Darex milling cutter grinder, and (finally) know how to use it. As I was warned by a more knowledgeable user, it takes a good bit of practice to be good, even with their so-called 'automatic' method.

Half-a-tenth is pretty tight, but if the stone is kept dressed, and the final cuts are done very fine with a freshly-dressed stone, you can hold that. I only grind HSS. I leave carbide to a pro sharpener.

Since quite a number of years ago, I have not bought anything but good- quality USA or Canadian cutters, even as "single-purpose" tools. The few Chinese cutters I still have are things like (very) rough facing mills with replacable inserts and a few lathe boring bars. The milling cutters are not accurately positioned from insert holder to insert holder, but OK for gross facing; never for a finish pass.

Lloyd

Using your own grinding machine I'm wondering if you couldn't install a drop indicator (of sorts) to get readings directly on the grinder itself. At least that way you can check size, concentricity and taper all at the same time.

Tom

snipped-for-privacy@aol.com fired this volley in news: snipped-for-privacy@googlegroups.com:

'Probably could... I was looking for a "bench" method.

Lloyd

Most people have a height gauge, indicator and a V-Block so that's the quick and dirty way to do it.

snipped-for-privacy@aol.com fired this volley in news: snipped-for-privacy@googlegroups.com:

Yep, but with 3 and 5-flute tools, different v-blocks. I have the height gauge. I can also do the check on the Darex, but I would have to mount and check 'good' tools that way, too.

Again, I was looking for a sort of "shop craft" method. Apparently, none exists, or is so old as not to be employed anymore.

Lloyd

Why would you need different v-blocks for 3- & 5-flute tools? From a few posts ahead of this one:

Mic the shank diameter.

Place shank in V-Block, put dial indicator tip on high spot of shank (center) and zero out indicator.

Move indicator to flute, measure high spot on flute, difference between shank and flute reading is radial value that value X 2 gives you the difference in diameter.

If needs be, check each flute to see what the run out may be.

rangerssuck fired this volley in news: snipped-for-privacy@googlegroups.com:

An awful lot of things have to be 'dead-to-nuts' perfect for that to work.

If there's even a scant second of slant on that v-block, using the 'shank' method guarantees that the tool will look tapered, even if it is not.

The purpose of different V-blocks is so that the diameter can be measured at the point of interest, instead of (up to) several inches away from the reference point.

My existing methods work OK, even if they aren't what I was hoping for in a 'crafty' way.

Lloyd

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