Drilling centres in long bar without a fixed steady.

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Gauge3

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Well, a couple of weeks ago, the old machine orphanage I operate gained some new children. As usual, I wasn’t planning on buying anything but a visit to a tool dealer uncovered an EW (2.5”) lathe in very good condition. It came with 3 & 4 jaw chucks, faceplate, boring table and vertical slide. It also had the backgear and change wheels. There was no motor or countershaft – but the old pulley shaft and pulleys were all in the box.

It was pretty complete and in good order for a lathe that started production in 1947, although mine is probably younger than that as it has no ‘Stringer’ plate. All this kit for about half the price of a new Chinese mini-lathe. It’s small enough to pick up and carry about but robust enough to do real work. Ideal I thought for an “inside” lathe. Inside in the warm that is!

So, I’ve fixed up a table with a lump of worktop for a surface and have started to think about making a countershaft to power her up. However, the Picador bearings are plain oilite ones and the shaft is quite badly scored. No, problem I thought, I’ll knock up a new one.

The shaft is 5/8” in the middle, so I found a bit of rusty 5/8” and cleaned it up. Problem, it wouldn’t fit in the mandrel of the ancient mariner (my old Myford) to drill thge required centres. I needed a fixed steady to drill the centres but whilst I have the castings – it’s something that’s never quite got completed (there’s a lot of things like that I’m afraid).

Casting about I found an old flange that had a 5/8” hole in it and initial thoughts were to use it with a lump of wood to make a temporary steady. Then I had an idea – and I’m sorry if this is sucking eggs for some of you. I found a 1” piece of scrap MS just over 5/8” and turned it halfway down to fit the hole in the flange. Then I drilled it enough to guide my centre drill. I had intended to hold the bar in the vice, slide the flange with guide over it and use an electric drill to centre it.

I didn’t end up doing it this way, although I did use the flange as a filing guide to clean up the bar ends. It occurred to me that my drill press has a 1” hole in the table centre. First thoughts was to use an angle plate to hold the bar upright but (unusually) I then had a second (and temporary) moment of brilliance. I have a Keats plate.

I used the Keats to hold the bar upright on the table and used the guide to centre the drill over the bar. I clamped the Keats down, removed the guide and drilled away. The other end was simply a matter of reversing the bar.

No handy flange or Keats plate? Well I could have drilled some scrap to 5/8” and used a simple angle plate on the drill press (with some fiddly set-up). It could have been done in the vice with an electric drill too but not as easily.

I hope someone finds this useful – I’ve seen lots of good stuff on the site and hope this small contribution is sufficient thanks.
 
An interesting post.

I'm not sure that I am visualizing correctly what you said.

A picture is worth a thousand words.

th_wwp

SAM
 
I think i can visualise what you did. sounds a good tip. How did you centre the bar with the axis of the drill? use a DTI or line it up with the flange and guide? and how long was the bar? by coincidence i've just come in from the shed where I had a devils job trying to centre drill the end of a 8 1/2 inch bar in my peatol (Tiag lathe). even with the tailstock turned round just bearly enough room on the end of the bed. ended up grinding the centre drill into two, but i actualy have a keats type v block .As its far too big for the lathe never consider it for anything these days. Ah well, I live and learn! wish I had read your post before I went into the shed!
 
Hi Sam - yes I completely agree about "picture worth" etc and it is something that I find particularly useful. I don't normally have a camera handy in the workshop but I have 're-staged' the set-up to help explain it a bit better.

The bar was about 10"long by the way...



Workshop - Centre Drilling - crop1.jpg


Workshop - Centre Drilling - crop2.jpg


Workshop - Centre Drilling - crop3.jpg


Workshop - Centre Drilling -crop4.jpg
 
For those who don't know what an 'EW Lathe' looks like - here it is.

And I've also just done a test cut to check the between centres set-up. Next will be some sort of 'H' shaped contraption to hold the countershaft.

Oh, and to answer the other question - I simply used the guide to position the Keats in the right place by moving the drill up and down tll it entered smoothly. I thought it best to remove the guide once everything was lined up - as I've broken centre drill tips off before and I wanted to be able to clear swarf away easily.

Seems to have worked out fine.

Workshop - EW Lathe - crop6.jpg


Workshop - Centre Drilling - crop5.jpg
 
Gauge3,

Thanks for the pictures.

Now I can understand what you did.

I have to file this for future use.

SAM
 
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