Lathe improvements?

Two raw brazed items were made because I know my ability to make scrap.

I did not (yet)

The 210 big hole lathe will look something like this

Edited By Niels Abildgaard on 30/04/2020 08:21:49

The Battle Ship is a tangential holder for 2 times 2 mm carbide.

I use it for more than 90% of my swarf.

On a clear day I have line of sigth to New York

Edited By Niels Abildgaard on 30/04/2020 08:27:58

Edited By Niels Abildgaard on 30/04/2020 08:28:54

The 210 big hole lathe is so miserably manufactured that I will ask it to leave house when it functions.

My new 250 lathe on the other hand is nicely made and can stay.

It uses two 45-75mm tapered bearings and I will make a new spindle looking something like this:

Thank you posting the extra tool photo's, Niels - I like that design very much..

You have a new 250? ..with bigger bearing housings?

New York here I come

If You want one for your Hobbymat let me know and we start a new thread.

My first chineese 250 lathe had 30/62mm  bearings and MC3.

MY present 250 has 45/75 and MC4 in nose.

This can be changed as shown without changing sacrosant chineese cast iron.

Edited By Niels Abildgaard on 01/05/2020 08:55:16

The significance of having a line of sight to NY only struck me today (a dull day at work..) - the Dover Strait makes a very narrow window to look through.. Now I see where you are, I understand how Stuyvesant must have got there.. ..not even any turns to make..

I'm always interested in tools that sit firm on a slide with almost no overhang, as everyone should be.. I think I have it figured enough for my own experimentation, for which I thank you again. I'm sure that if you wanted to post further details, others might be interested too, but of course I don't wish to impose on your welding & turning time - mankind is waiting..

I just found this with Google, after being challenged to find any one other person that can use the phrase "living room lathe". So thanks for making me not wierd.
I might as well post a photo of mine... https://photos.app.goo.gl/U2X3SLH3YBWLkehz8

That is the spirit

Servant,dogs and children not allowed near the lathe

A box came this morning from Pilzen with a 210/38mm hole lathe bought for 780€ via Amazon de.

Two days late in Corona time is OK.

It got power and ran very well and everything else was OK and well made.

An hour later it looked  like this:

Plan is to put a bigger spindle in and power it with a 1.5kW/3000rpm sewing machine motor.

I am still looking for a simple yardstick  of hobby lathe performance.

Edited By Niels Abildgaard on 20/11/2020 18:41:19

Edited By Niels Abildgaard on 20/11/2020 18:41:50

The MeGa 50mm hole spindle is in and waiting for a 1.5kW/3000rpm/12 Nm industrial sewing machine motor.

The Spindle flange and tube is copperbrazed..

Screwed on flanges or chuck are dangerous due to the instantaneous stopping of motor.

That certainly looks a substantial spindle assembly. Presume you have access to a large lathe and other engineering facilities to braze and machine a spindle of that size. (machined after brazing?)

I agree about the vulnerability of screwed on chucks but having gone to the trouble you have, why not elect for camlock mount?

Ian P

To match the oversized spindle bore, a chuck would have to be far too big for that little lathe, so the whole exercise is a futile wast of time and money.

This is a _model_engineering_ forum, the whole raison d'etre of which is to "waste" time and money.

And I disagree with the premise. It is frequently useful to be able to have larger diameter sections of parts on the opposite side of the chuck, even if the parts won't fit through the chuck.

And it is relatively easy to make the hole in the middle of a 4-jaw chuck larger, you only need to shorten the screws and bore out the body.

I have made a Camlock mount. It's a lot of work.

http://bodgesoc.blogspot.com/2017/05/harmonic.html

If anyone fancies the idea, though, the cams are probably best bought, and were fairly inexpensive here:

https://www.gatemachinery.com/product/cam-d1-4/

Though they show out-of-stock at the moment.

The 125mm dia raw flange was machined on my 250 lathe that has been liberated by my son and the tube as well.

I worked at a copperbrazing site many years ago and the new owner did it at a fair prize..

If I knew where to get some Easyflow(No,No) I would have done it in garden.

The important step of turning thread and bearing seat in one go was done on my late 250.

The main zeal of exercise is to keep overhang from front bearing as short as possible and show the Chinese that they can do a better job within the given constraints.

It was one reason for giving my Boxford away and starting on this expensive and futile journey,that chucks were getting uncomfortably heavy.

Mass shall not exed my latest 50£ 125mm four independent jaw. It is incredibly precise and well made.

When I plane the two faces of a 90mm disc there is maximal 0.02 mm thickness difference.Often less.

Hole is 30mm and can easily (I think) be opened to 45mm.

A 160 mm independent four jaw would come with a 50mm hole but would be to  heavy for old men.

A 160 mm independent four jaws that has moving parts from the manufacturers line of 80mm chucks will be optimum and can be lower mass.

The standard workholding equipement for a 50mm bore 180/210 lathe can be:

An ER40 collet holder that can be adjusted say 0.1mm relative to spindle flange and cover 2-29mm dia:

Standard 3Jaw 125mm Chuck.My old PratBurnered has 36mm hole.

Standard 4 jaw 125 opened to 45-46mm and a low mass 160mm four jaw with 50-55 mm hole.

All mounted with front screws.On my 180 it takes less than three minutes to change fro 3 to 4 jaws.

Edited By Niels Abildgaard on 25/11/2020 08:48:05

Edited By Niels Abildgaard on 25/11/2020 08:50:32

"...This is a _model_engineering_ forum, the whole raison d'etre of which is to "waste" time and money..."

Andy, never a truer word.....

Matt

What a strange outlook!

Despite the title this is not just a forum for model engineers, who I am sure do not all waste time and money.

There are many avid user of this forum that have no interest on models or steam.

Ian P

Please find a picture of boring a 50mm hole in a 125mm four jaw chuck on a 180mm lathe with 30mm hole.

My 210 mm lathe is not running yet but has a 50mm hole in spinde.

Next picture shows how it will look on the 180 lathe ready for action.

I have not yet thought of an elegant way to cut the jaw screws.

They are hardened.

Any sensible objections?

From the photos, particularly the first, it looks like there will be very little left of the inner part of the screws when they are cut to clear the 50mm bore. The remaining flanges are all that will hold the jaws and the screws in the chuck.