The Shop > Our Shop

Red lathe woes..or 'The joy of owning a piece of history'

(1/6) > >>

DavidA:
Although I've been busy doing other things recently, I managed to settle down to spending some time in the warm outhouse today. It is raining very cold water all over the garden so it seemed the best option.

Now,  as some of you will know,  I have an old lathe of unknown provenance. By the quality of the build it is obvious that it was an expensive bit of kit when it was new.

But it is quirky.  And yes,  it's red.

I'm going to note down some of the odd things as they become apparent. All those of you with (relatively) modern lathes may consider yourselves blessed.

First,  a picture. (not sure where it will appear).

Ok.
For some time I have known that the spindle nose M2 taper socket was damaged. Now was the time to do something about it.

I was watching Doubleboost's video on making a tailstock die holder and more or less followed that method.
Problem was,  as the nose socket is damaged I can't stick a centre in there to support one end of the centre I want to use to set my topslide over.
No problem, fit the three jaw and chuck up a bit of bar.  Create a 60 degree point. use that as the location for one end.
I have a centre that is wide enough at the 'big end' to fit in the hole of the tailstock without going right in,  so that was the other end sorted.

Lots of gentle tapping and the dial guage was finally reading zero over the length of the 'alignment' centre.

Great ! ready to bore out the spindle nose. Remove all the gubbings used to set up; including the chuck.

Ah....
Now you see the disadvantage of a gap bed.

With the saddle fully advanced towards the headstock and the topslide as far forward as possible on the slotted table I can't get the boring tool within three inches of the spindle nose. And that is before any cut is made.

Bugger !!  I'm going to have to make some kind of extension that bolts to the table and bolt the topslide to it.

But not today.

You can see the problem in the (earlier) picture.

For scale,  the slotted table is 5.5" from end to end.  Also note that the saddle is as far forward as it goes and the tailstock is hard up against it.

Dave :bang:

bertie_bassett:
would it be worth fabricating a section of bed to fit the gap? iv seen it done for the tail end before

would take some carefull work to get it accurate but might be better in the long run?

vtsteam:
It can be done somewhat tediously (and carefully), with a small boring bar, and a new male taper for a test piece and some blue color -- per scraping. The compound slide angle is set by test and refinement  -- checking of the pattern of the rub. I'll probably be doing it on my lathe building thread at some point in the near future.

In general, you set the angle as close as you can get it. Then take a light cut. If testing with the blued plug shows it is hitting at the front of the cut, the angle is too fine, so tap the compound slightly to compensate. And vice versa if the rub shows it hitting at the back of the cut. You gradually "sight in" on the right angle by successive comparisons, and get to the point where it hits the tapered plug evenly whle you cut. When you have cut all the way from front to back and the taper plug contacting throughout, you're done. As in scraping, the blue is extremely sensitive.

DavidA:
Bertie,

It would be a major undertaking to do that on this lathe.
Although it is a huge inconvenience,  I'm not stuck for the use of the mt socket. Also I don't want to change the original machine.

VT,

What don't show so well in the picture (must get another one) because the chuck is fitted,  is the huge distance between the Morse taped end of the mandrel and the position of the table (and hence my tool post) even when the table is as close to the mt socket as possible.  I would need to have about eight inch of overhang on the boring tool if it was to get right inside the socket.

Many lathes have an 'H' shaped saddle. My Rufold lathe does. This,  along with the bedways going right up to the headstock (non-gap) allows one to get up close to the mandrel.

As for the procedure,  I have no problems with that. As I mentioned,  I did it before I realised I hadn't allowed for the chuck being there.

So I had my topslide all set over and ready to go.  But couldn't reach the headstock mandrel with the too.

I'll fit up something to do the job. It's not urgent.

Any way, I will be able to use the Denford when I get a PSU for it.

Dave.

Fergus OMore:
I am far from sure what you mean by a damaged No2 MT in the headstock spindle.

I have corrected a 'buggered' tailstock on a Boxford with a finishing No2 MT reamer. Not mine- belonged to Newcastle City Council. Again, I recall another one.

So if the spindle is 'soft' and you can't reach in with a normal length reamer, you can use and extended jumper to bring the reamer forward. I'm assuming the gap is the problem!

However there is construction of a sinebar to cut No2MT. One of my mates did one fr his ML7 by using a the Classic 10" sine made from silver steel and a setover of 0.250" and this was the old No2MT ( until someone arsed it)

I've Colin's sketch if you want it.

Norman

Navigation

[0] Message Index

[#] Next page