ER 40 Milling nose

The great John Stevenson thougth little of MorseCones for lathe noses and more of ER threads.

I was playing around with my camera and my HBM BF 25 Vario milling machine with MC3 spindle nose (All my lathes bar first Myford and soon to be my sons WM250 have had MC3 as well) and some nice ER 40 gear.

The machine will be cheaper,better and nicer with ER40 direct.

The lower bearing is the 32007 (62/35/18)  and can be replaced by 32908(62/40/15) in the new ER40 spindle

Edited By Niels Abildgaard on 26/09/2020 08:42:12

Edited By Niels Abildgaard on 26/09/2020 08:58:49

Hi Niels are you going to make a new spindle with integral ER 40 nose or a different adaptor into the Morse taper.

David

A new spindle to save heigth

Edited By Niels Abildgaard on 26/09/2020 09:32:31

Edited By Niels Abildgaard on 26/09/2020 09:32:49

I watch with interest.. I can also see that there could be advantages in freeing the top end of the spindle from a drawbar, too..

Nice project, I look forward to seeing developments..

Have you considered how you will hold Morse tooling in the new spindle arrangement, particularly drill bits?

I have never drawn it up, but what size Morse taper would fit within the confines of the ER40 collet cavity?

No ,never

What I have done is to turn mistreated morse male cones cylindric and then hold them in ER collets.

I will try to scheme Your idea

An ER40 size collet can easily grip a MC3 and very marginally the thinnest half of a MC4

Edited By Niels Abildgaard on 26/09/2020 19:31:50

Why not change it to R8. You can hold most tools directly and use an ER holder if required. Putting a thread on the nose risks wear, although in the hobby workshop will outlast most of us.

Since the range of collet sizes is from 3-30mm diameter, to utilise them all fully would need at least 4 diameters accomodated from the face of the nut. A much larger lower half of the spindle would be needed to take a 30.5mm bore. The size of the clamping range of these large collets is such that it is doubtful if cutters in the smaller sizes would be held accurately or tightly enough.

R8 cannot accomodate bigger than 20mm cutters and then only with very limited depth which means that standard length 20mm cutters project a long way.

Edited By old mart on 26/09/2020 19:29:24

The Quill is bored 62 for the lower bearing that can be 40mm inside.

Can You please explain another way for my understanding?

As long as the length of, say, 110mm from the end of the threads can be 30.5mm then that gives a decent choice of fitted lengths for the larger longer cutters. There needs to be room in the design for spanner flats directly above the nut. Some long spanners will be required as the recommended torque for larger cutters is 145 ftlbs.

I converted a Tom Senior spindle from MT2 to R8 last year and am very pleased with the results. R8 is still a very popular fitting and there is a wide variety of tooling. You would have to make special adaptors if you wanted to use shell mills with an er40 spindle, although there would be no need for a drawbar.