Blank end Arbors

[VicParticipant @vic]

Are blank end Arbors soft all the way through? Just wondering if I can bore a hole all the way through an MT2 arbor. Or can you buy one with a 10mm hole through the middle?

[jimmy bParticipant @jimmyb]

I believe they are fully soft, at least every one I have ever bought has been!

 

Some time ago, when things were a bit quiet at work, I knocked out a box full whilst no one was around. should last me out!

 

Jimb

[DC31kParticipant @dc31k]

You could test it yourself.

If the arbor is hard, all you have wasted is the time it takes to re-sharpen a drill bit.

It may not be relevant, but 10mm through a MT2 might obliterate any drawbar thread at the small end.

[DC31k]

On DC31k Said:

You could test it yourself.

If the arbor is hard, all you have wasted is the time it takes to re-sharpen a drill bit.

It may not be relevant, but 10mm through a MT2 might obliterate any drawbar thread at the small end.

If it’s too hard to drill, I’ve lost the cost of buying it! I don’t need a draw bar.

[VicParticipant @vic]

Not as cheap as they used to be, but I’ve ordered one from RDG Tools.

[David George 1Participant @davidgeorge1]

HI  Vic  Let us know how you get on. I have machined the end section making one to a chuck arbour and another into a boring head but neverthought of drilling through the taper part. Whilst at work we would make some parts which were part finnished then carburised then we would machine of the carburising of some areas to remove the carburising then it was sent for hardening as only the carburised areas would harden. These were ground on the hardened areas and the soft areas were drilled tapped milled etc to finnished item.

David

[old martParticipant @oldmart]

I have never tried to drill right through a MT arbor. However, I have cut off the tangs from a couple of drill chuck Morse Taper arbors and drilled a hole about 1/5 of the taper length without any bother to allow greater stroke of the tailstock in my 7 X12 mini lathe, which also increases the available bed length. The hole accepts the end of the tailstock leadscrew which is self extracting. It is common for soft end MT arbors to have a drawbar end rather than a tang, so I recon it would be possible to drill right through.

Your 10mm hole would only leave 2.25mm wall thickness at the small end of the MY2.

[David George 1]

On David George 1 Said:

HI  Vic  Let us know how you get on. I have machined the end section making one to a chuck arbour and another into a boring head but neverthought of drilling through the taper part. Whilst at work we would make some parts which were part finnished then carburised then we would machine of the carburising of some areas to remove the carburising then it was sent for hardening as only the carburised areas would harden. These were ground on the hardened areas and the soft areas were drilled tapped milled etc to finnished item.

David

The one I got from RDG is soft on the end and through the middle so drilling a hole through the middle was no problem. 😉

[Martin KyteParticipant @martinkyte99762]

Does no one machine their own these days. I know it’s easier if you possess a taper turning attachment but one you are set up you can make a batch to last you years.

[VicParticipant @vic]

I’m just waiting for the collets to arrive now and I can try it out.

[old martParticipant @oldmart]

We have a taper turning attachment on the Smart & Brown model A and I decided to produce a MT2 taper. What you need to appreciate is that a Morse taper requires accuracy within a few seconds of arc. I set up the angle using a true running male MT2 in the spindle and a DTI set exactly on the centreline. The tool height has to be exactly on the centreline also. The setup would only work for MT2 as for some unknown reason every Morse taper is a different angle. The MT2 produced was unused for years until I wanted a cutter to go in the pillar drill which has backgear to cut various diameters of Tufnol used to make cable pulleys for the flying banana.

Vic, I see a tang on your arbor but no 10mm hole. Is the tool a small rotary broach?

[old mart]

On old mart Said:

. Is the tool a small rotary broach?

see: https://www.model-engineer.co.uk/forums/topic/taping-small-holes/page/2/#post-818365

[VicParticipant @vic]

It will possibly serve two purposes. The primary purpose for me is as a sensitive drill. In addition it could be used as a small rotating centre with interchangeable centres.

Inspiration was from here:

https://youtu.be/L0ZTw5J8oTE?si=6ng5kst7cnbtFlDM

 

[Martin Kyte]

On Martin Kyte Said:

Does no one machine their own these days. I know it’s easier if you possess a taper turning attachment but one you are set up you can make a batch to last you years.

On Martin Kyte Said:

Does no one machine their own these days. I know it’s easier if you possess a taper turning attachment but one you are set up you can make a batch to last you years.

The advantage of m/cing your own blank end arbors from bought in stock is marginal, considering the cost of the material.

Of course it’s ok if you have the material in stock or enough in the scrap and odd ends bin.

[Martin Kyte]

On Martin Kyte Said:

Does no one machine their own these days. I know it’s easier if you possess a taper turning attachment but one you are set up you can make a batch to last you years.

I did, but having a “spare” CNC machine made it very, very easy!!

I also ran off a lifetimes worth of slave live centres that day…….

 

Jimb

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