MT end mills slightly corroded

[Dr. MC BlackParticipant @dr-mcblack73214]

Posted by old mart on 09/05/2021 17:29:49:

I would also avoid using any tanged cutter sideways, it is looking for trouble. That is why mills use drawbars.

Which prompts me to ask why does anybody manufacturer tanged MT2 End Mills?

MC

[Ex contributorParticipant @mgnbuk]

Which prompts me to ask why does anybody manufacturer tanged MT2 End Mills?

Spot facing ?

Nigel B.

[Graham MeekParticipant @grahammeek88282]

Morse Taper cutters that resemble an endmill, but have a Tang, and not a Tapped hole, are usually used to produce counterbores. The thrust from the cutter during counter-boring tending to push the cutter into the Morse socket, rather than winding it out during milling.

Without the tapped hole it would be foolish to use these for milling unless one wants to lead an exciting life, with a possible visit to A&E thrown in for good measure.

Regards

Gray,

[Dr. MC BlackParticipant @dr-mcblack73214]

Posted by Graham Meek on 10/05/2021 08:03:11:

Morse Taper cutters that resemble an endmill, but have a Tang, and not a Tapped hole, are usually used to produce counterbores.

That's very useful information which I shall bear in mind.

Unfortunately, they are NOT marked with size; I shall see if I can determine those.

MC

[Nicholas FarrParticipant @nicholasfarr14254]

Posted by Graham Meek on 10/05/2021 08:03:11:

Morse Taper cutters that resemble an endmill, but have a Tang, and not a Tapped hole, are usually used to produce counterbores. The thrust from the cutter during counter-boring tending to push the cutter into the Morse socket, rather than winding it out during milling.

Without the tapped hole it would be foolish to use these for milling unless one wants to lead an exciting life, with a possible visit to A&E thrown in for good measure.

Regards

Gray,

Hi, however this type with a left hand spiral and a right hand cut, should in theory, tend to push the cutter into the taper.

Regards Nick.

[not done it yetParticipant @notdoneityet]

I shall see if I can determine those.

Easy enough. Drill a hole as a pilot, apply cutter axially, then measure the new hole diameter.

[Dr. MC BlackParticipant @dr-mcblack73214]

Posted by not done it yet on 10/05/2021 12:21:45:

I shall see if I can determine those.

Easy enough. Drill a hole as a pilot, apply cutter axially, then measure the new hole diameter.

I was thinking of using a Digital Caliper across the end to measure the diameter directly.

I appreciate that this would NOT work with an odd number of flutes.

I think the cutters are too large for any drill gauges in my possession.

MC

[not done it yetParticipant @notdoneityet]

In my view, the practical hole size cut is likely more accurate than the theoretical assumption (of concentricity).

[Graham MeekParticipant @grahammeek88282]

Hi, however this type with a left hand spiral and a right hand cut, should in theory, tend to push the cutter into the taper.

Regards Nick.

Hi Nick,

That might be true, re cutting forces, but in my experience these type of cutters are more likely to be "end cutting reamers". Many of the chucking reamers I have are LH spiral.

They may well work as an endmill, but if they were mine I would cut the Tang off and tap for a drawbar. The other problem with these cutters is not all of them are HSS, I have been given some which were Carbon Steel.

Regards

Gray,

[Dr. MC BlackParticipant @dr-mcblack73214]

Posted by not done it yet on 10/05/2021 13:27:04:

In my view, the practical hole size cut is likely more accurate than the theoretical assumption (of concentricity).

Further to previous, all four of the cutters are right hand with an even number of flutes.

I found that I did have some thread gauges with large holes and determined that two are 1/2", one is 9/16" and the last is 1".

But one of the Morse Tapers has been machine to a fairly constant 15mm and fits in a collet.

I'm now seriously considering machining the other three in a similar way. Unfortunately, the spindle on my lathe isn't sufficiently large to hold these End Mills while I machine the tapers to parallel.

The Scotchbrite arrived today but I may no longer need to use it!

MC

MC

[Chris GunnParticipant @chrisgunn36534]

I'm with Bernard, if they were nice and shiny I would still not use them for milling. There is probably a reason they are rusty and you got them for free. Once you have cleaned them all up and you have modified them by turning the shank down or adding a drawbar to possibly make them safe to use, they will give you limited service for all the effort before they need sharpening again. they may put you off milling as well. Put them back under the bench, and buy some modern ones, and buy the sizes you need.

Chris Gunn

[Dr. MC BlackParticipant @dr-mcblack73214]

I was given a lot of tooling by an old chum whose wife decide that they would be moving into a flat so he had to give up his workshop which was larger than a double garage.

These End Mills have never been under MY bench – generally, I don't keep this sort of thing in my shed but in my centrally heated home from where I take what's needed to the shed.

They will go into the forthcoming projects drawer until I can get the use of a bigger lathe using which I can turn the tapers parallel.

Looking at the cutting edges, they look to me as if they have had little use and will probably last me out.

[Chris GunnParticipant @chrisgunn36534]

I just had another look at the pics of the end mills, and note what could be a hole in the end. Hard to tell if it is a centre or a hole. If it is a parallel hole they could be countersinks, with the hole being provided for a pilot. I have some similar under my bench, complete with pilots.

Chris Gunn

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