Vintage Portmac vertical milling machine

I'm now the proud owner of this suitably vintage milling machine and apart from the colour (which may or may not suit your taste) it appears to have been very well cared for and cuts surprisingly well. I've taken a few test cuts using 1/2" end mill in mild steel and the cutting was smooth and clean, something I didn't really expect as I'm used to a much larger machine (3 HP SEMCO at work).

The machine does not use a draw bar and I'm unfamiliar with the collets which I'm guessing may be difficult to source. It came with quite a lot of tooling including a few 1/4" and 1/2" collets. For smaller tooling I'm wondering about making some custom tool holders with a fixing grub screw (grinding a flat on the tool).

All comments welcome (including what colour I should paint it).

Brian

You only need 6 collets to cover all the relevant cutter shanks.

1/4" 3/8" 1/2"

6mm 10mm 12mm

Very useful looking little mill

Z axis adjustment looks interesting … presumably it is this ‘BC’ model: **LINK**

http://www.lathes.co.uk/portmac/

MichaelG.

Having just checked what I actually possess, I need to correct what I stated earlier. I have one each of 1/4", 3/8" and 1/2" collets. The milling machine also came with a good amount of end mills -- I'd guess at about 100+ which should keep me going a while.

I don't have any metric collets, which may or may not be a problem.

Yes, the Z axis is "interesting" but it seems to work very well. I've only tried it for a couple of test cuts but I rather like it already. Unlike most older machines I've owned, this one appears to have very little wear.

I read the same webpage which mentions the "BC miller" but I wonder where the author gets that name from. Mine has various names on the castings including VM20 and VM4.

When I Google "Portmac" all I get is Apple Mac computer ports!

The well-known Lathes website states the following:

the spindle accepted standard dead-length Crawford collets (1.5" long with capacities ranging from 1/8" to 1/2" )

Is this something I could obtain without selling a kidney? 

Edited By AJAX on 04/10/2021 21:25:33

Apparently they may be the same collets as used on a Herbert or Ward Models "0" or "1". I'd be grateful if anyone could confirm that.

If I don't make any progress with collets then I may look at fitting an ER system instead (that may in fact be the better option) making use of the existing nose thread.

That's a really nice little machine! Not seen one before. 😎

.

Disappointing to see that even this got me nowhere: **LINK**

https://www.bristolmodelengineers.co.uk/?s=portmac&submit=Search

MichaelG.

The arrangement with the splined spindle is like the Myford VMB. Is there a fine downfeed?

One could make those collets I'd have thought.

.

From the lathes.co.uk description, John:

[quote]
The head could be slid up and down the face of the column through a range of 7" .
Fitted with a screw-on nose cap, the spindle accepted standard dead-length Crawford collets [ 1.5" long with capacities ranging from 1/8" to 1/2" ]and had a travel of just 1.5 inches with the feed handwheel, threaded internally, sitting just above and surrounding spindle housing so that it acted directly upon the quill - a most economical design, and possibly unique.

[/quote]

MichaelG.

.

Edit: __ killed a smiley

Edited By Michael Gilligan on 06/10/2021 08:54:38

Yes, there is. Rotate the large hand wheel (through which the spindle passes) and the feed can be finely controlled. Fingers also pass very close to the rotating spindle, so I might see if I can fit some sort of boot.

I have too many jobs on at the moment (I stripped down a Multico A3 table saw and it's now an explosion of parts being repainted) but when I make some room I'll take more photos and possibly a video of it running. I think that will be worth doing as it seems a quite unique machine.

I don't know whether I could make one of those collets but I'm sure I could turn something that would be useful. I did actually enquire about getting collets made (or adapted) and the price was not unreasonable but more than I'd like to pay now. I'm still wondering whether I can't make an ER collet adapter than fits on the spindle nose.

Yes, the apparently world-wide absence of information (apart from the Lathes website and a couple of posts here) is a bit curious.

**LINK** is an article on making myford style collets, a similar method should work.

I have been working on this project somewhat intermittently but the mill has now been repainted and a new 3 phase motor fitted. Rather happy with the Leroy Somer 0.25 kW motor which cost only £31.20 including Vat and delivery and comes with a 3 year warranty.

.

Please see my query on the concurrent ‘Chinese Lathe’ thread

Thanks

MichaelG.

DuckDuckGo finds MG's link halfway down the first page. The link also seems to answer the colour point.