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View Full Version : Rear mounted quick change tool post on 70 yr old bench lathe



Ian9toes
03-17-2017, 04:38 PM
G'day, here's some pics of my 70 yr old Australian made 8x17 and rear mounted quick change tool post.

I wasn't as stoked with the rear mounted part off blade holder that came with the lathe as I was originally.

I didn't like its lack of practical height adjustment, so I searched the net for ideas, but nothing jumped out at me, plus they all needed a mill to make them, which I don't have.

A lack of a mill probably forced me to think differently to those who had one. What I came up with is a rear mounted quick change tool post. Not only does that give me the easy height adjustment I wanted, but it also allows me to easily remove the tool holder, and give me heaps of room to move. Or I can use different tools back there, a bit like having a turret lathe.

Note how the tool post is hanging off the back of the cross-slide. The base is 1/2 inch steel plate, the tool post sits on two bits of 20mm welded together. The whole setup weighed 6.5 kg's on my bathroom scales.

The two bolts add extra security as I didn't want the tool post to rotate on the centre stud.

The blade holder was a zero rake holder so I cut off the shank and welded the blade holder to the tool holder for a 4 degree positive rake.

I've had a play, and it is very sturdy.


http://i199.photobucket.com/albums/aa47/ian9toes/0efe5f654ba9e3782af1a3c0aea6a4d9_zps2ivoy2fk.jpg

http://i199.photobucket.com/albums/aa47/ian9toes/c76f9013a188015b7411dd033b945f64_zpsg6dnwknk.jpg

I really like the cantilevered bed, it gives it a watch maker lathe feel about it

I picked it up from gumtree for $700 apparently back in 1948 a brand new one was worth 115 pounds. They were made in Sydney from as early as 1939 to the late 50's, I don't know the true age of mine, but I like to think of it as being 70 years old, which is about the midway point. The badge on it is "New Gregco" which were made by "Blackberry and Austin".

It's a beautiful little machine with a centre height of 4 3/16-inches and a between-centres' capacity of 17-inches, basically a 8x17.

Despite being smaller than my 9x20 (soon to be moved on) Chinese lathe, it is considerably beefier in many aspects. For example the cross-slide dovetail on the New Gregco is more than twice that of the Chinese one. The compound dovetail on the New Gregco is actually wider than the cross-slide dovetail on the Chinese one.

Here's a comparison of the two compound rests.

http://i199.photobucket.com/albums/aa47/ian9toes/2761fc8ae798856399745238a70c8e91_zpspalpzgry.jpg

Check out the simple belt tensioning device, the weight of the beefy old 880 watt motor is what provides the tension.

http://i199.photobucket.com/albums/aa47/ian9toes/36ecf00e4cf575a6064937e9d434d31c_zpsdn5wbu1w.jpg

George Bulliss
03-18-2017, 09:52 AM
Bump

Got stuck in moderation filter.

BCRider
03-18-2017, 11:59 AM
Welcome aboard! Seems like a bunch of new folks are introducing themselves recently.

I gotta agree with you on the design and looks of your lathe. It's an oldie but a goodie. And the stand and overhead countershaft is as intriguing as the machine itself

mattthemuppet
03-18-2017, 12:42 PM
That's a cool looking lathe, looks very solid for its size. I like the rear parting holder too. That's something I've wanted to do for a long time.

lakeside53
03-18-2017, 12:55 PM
Post the pics of the original rear tool post that you posted over on PM. You are limited to 4 pics per post, but not per thread so have at it!

flylo
03-18-2017, 01:20 PM
I have a Warner Swassey & a Logan with dual front & rear tool post, the rear one for mostly parting off but never saw a rear only one.

Ian9toes
03-21-2017, 07:08 PM
Because of the 4 photo limit I couldn't fit everything in the first post.

I replaced the leather belt with something made in this century.

With the back gears it has 6 speeds, on the lowest speed you can actually watch it turning around.

I plan to put a 3-phase motor on it with a VFD inverter with a reverse switch. That way I get "infinite" speeds, plus I can crank up the belt tension and leave it on one position for the most part. And with a soft starter I should be able to remove the clutch. The current motor (pun intended) trips out the fuse if turned off and on too many times in close succession, which is why it has the clutch in my opinion, though I could be wrong.

With the clutch disengaged, I can leave the motor running while taking a measurement, but with a soft starter I should be able to just turn the motor off and on all the time for taking measurements or removing something from the chuck.

I'm hoping with a modern 3-phase motor and the clutch removed, I should have a quieter smoother running machine, which will be pretty impressive given it's already pretty quiet.

http://i199.photobucket.com/albums/aa47/ian9toes/083ed61a876468ff35db22c77a20d709_zpssejjmdqr.jpg

This is what it took to install the one piece belt. It was more work to remove the drive shaft and clutch from the frame than it was to remove the spindle.

http://i199.photobucket.com/albums/aa47/ian9toes/051f16c39222c95bd0c0376c5cf2bc1b_zpsuoe5jdu2.jpg

http://i199.photobucket.com/albums/aa47/ian9toes/eaf7609dba789c71bb925560e1a5eb0b_zpsy5zti0ib.jpg

http://i199.photobucket.com/albums/aa47/ian9toes/842ec29d6cec6d5bd585f272e7db0546_zpsbbnj1fh7.jpg