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Tool tips

Tool tip inserts are commonly specified using ISO references. These define things like tip radius, thickness, shape etc. One of the defined items is cutting length which is usually given the symbol L and is the length between one tip of the tool and an adjacent tip.

Now I would have thought all that eminently sensible until that is I order tips by the ISO reference and find they do not fit the tool holder. The reason is the cutting length is slightly longer which means the clamping screw hole is not centralised over its thread.

In my case the ISO reference was CCMT 060202 and the offending tip cutting length was 6.3 mm rather than 6mm. One tip I think is of American Manufacture and the other European. Of course 1/4" is 6.35mm ..... American! It's the 06 that is the offending reference that can apply to either cutting length, but the M reference does not change. (The M reference is the theoretical diameter of a circle that touches all cutting edges of the tip.)

Has any one else been caught out by this small difference and apparent inconsistent use of the ISO standard? Or have I misunderstood the application of the ISO standard?

Alan

Reply to
Alan Marshall
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The ISO 06 is equates to the ANSI 1/4". The American ANSI designation system predates the ISO so either you either have the wrong insert or your holder has a non standard insert. Of course a lot of inserts do have the hole offset to a degree so that the retaining screw when tightened biases the insert against the holder recess rather that just clamping it to bottom face.

The M actually relates to the cutting tip tolerance, in this case a low tolerance value.

Here's a site that will give you equivalents:

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Tom

Reply to
Tom

Thanks Tom, A useful site.

My toolholder and its tip are from a well known industrial supplier, the holder is supplied with a Sandvik tip. An ISO tip to the same number bought from an industrial tool supplier and is of American origin I believe and that does not fit the holder. Hence the query.

Alan

Reply to
Alan Marshall

Sandvik seem to have a bit of a habit of making toolholders that only take their bits..

-- Steve Blackmore

Reply to
Steve Blackmore

ISO means "the same", and that is the last thing any of these so-called "standards" are concerned with.

Originally British Standards were intended to be the lowest acceptable quality, and most reputable manufacturers were happy, and proud to state that their products were "in excess" of the relevant British Standard.

Those enlightened days are long past, with everything controlled by grey accountants in grey suits, and no-one ever makes anything that is better than the "standard", instead loudly proclaiming that their work is "in accordance with BS"!

Since the Americans can't turn Imperial into metric - e.g in the Hubble Telescope, et al, its no wonder that they and we can't agree what is the size of a 1/4" object.

Dave.

Reply to
speedy2

"International Standards Organisation", in fact, a clever acronym.

Reply to
Airy R. Bean

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