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Starting turning on an old lathe


Gazzar

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That's true. No wobble. There is play in the slides, though.

When I've the electrics the way I want them, I'll work on the bed levels, then adjust the slides so they are not tight.

Is there a decent oil to apply to the bed? WD 40 is rubbish at that sort of thing.

Oh, and the drill centres arrived today, as well as some grub screws I'll adapt for inserts.

Tomorrow is to be great weather, storms and rain, so should be in the workshop all day.

 

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8 hours ago, Gazzar said:

Thanks, 

I see where you are coming from, I think. I find getting the HSS to do what I want difficult, the inserts have worked better so far. Though I might get more HSS and experiment more.

Out of curiosity, what is a fast speed? I think my machine goes to nearly 1,200 rpm, according to the gear box plate.

 

Tool grinding with HSS does take practice, if you have a look on YouTube there are some good videos to get you started. 

 

As for RPM, that depends what diameter your cutting... However to give you an idea, our biggest lathe at work (which is a baby in the grand scheme of things but very powerful for its size) uses a 42mm insert drill regularly, it goes through mild steel at 1850RPM... The only reason we can't go faster is coolant pressure.

 

You need to learn about cutting speeds, the formula is:

(Cutting speed X 1000) / (3.14xR)

So if you had a piece of mild steel 100mm diameter you were finish turning at 325 meters a minute your RPM would work out to 637RPM.

 

Good quality inserts will have starting points for feeds and speeds on the box. Do note that you will need different grades for each material you want to cut, general purpose inserts are garbage.

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4 hours ago, Gazzar said:

I wonder if I've given up accuracy for the ability to handle larger stuff.

Can't see why, though.

And it wasn't expensive, so why not? The previous owner only used it to clean up the inside of thick wall pipe so he could use the pipe as crush tubes in bits he was making. 

It comes with a 12 inch 4 jaw chuck and a pile of alternative gears.

I've worked in an environment (and Ejparrott still does) where there's machines that can carry bits of metal over 1 meter diameter and 5 meters in length.... And we would be upset to not hold dimensions within 0.05mm.

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Good to know, I suspect you and EJ know what they are doing, unlike me!

I must be realistic in what I can achieve. Time and cash are the usual constraints, so I'll limit myself to general turning, hobby style. If I need quality, hubs or flywheels, I'll get my local outfit to turn them, they like small volume stuff as it's fun.

I'll explore HSS more on you tube.

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For oil for the bed you want slideway oil. Your lathe may have a tank for it in the apron and you press a button to pump a bit to the right places for you or you may have oiling points that you can pump a bit in with an oil can. They look like a ball bearing in a hole, as you pump the oil in they push in a bit to let it past and they can be all over. I've bought oils from westwaylubricants on ebay before and it's always turned up quickly. 

You may also have oil in your gearbox / apron just for lubricaing the moving parts. If you do there is usually a window for checking the level, although you often can't see through them :unsure:

That looks like a pretty serious piece of equipment! Fair play!

If your worried about damaging the thread in the chuck get or make some soft jaws. A bit of equally sized aluminium on each jaw is all you need. 

These arn't mine just pinched off google

img_3360.jpg?w=500

maxresdefault.jpg

Edited by Cynic-al
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Yeah both the photos are home made things, should've said that. A cheap bit of ali works well as you can throw it away when it gets marked. 

I'm not sure what to call them if soft jaw isn't technically accurate. Soft face or something like that?

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The Slide oil and oil can arrived today.

Assuming this hasn't been lubed in a decade, I guess the best thing to do is to pump oil into everything until it comes out somewhere clean? Then repeat with the screws half way along and then at the other end, for the slides?

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The lathes I work and the one i own are lubed little and often, if its a busy day then they see the oil can twice a day, but with only a small squirt.

 

Check your manual, there will be places you need to point the oil can, and yes, pump it through until its clean. then clean it all off and then apply a light amount.

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Thanks VB, regrettably, no manual came with the lathe.

Once it's flushed through, it will be little and often.

 

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No success. Different company. Very polite people though.

Anyway, I've pumped oil in everywhere. In most places it just goes in and flushes out the grey/brown stuff. But in some places the oil doesn't go in, it gets spat out. I'm assuming this means that I've to engage that lever before the oil can go in, or something.

It's made a difference, the main saddle is quieter to move. And the slides feel, slicker, I suppose. I've also figured out why the  main saddle has a 'skip', it's the rack bolted under the bed, as the gear moves from section to section, there's a miss beat, almost, that I feel through the wheel. Perceptible, but not an issue, and, since I've oiled the gear, nearly gone.

 

I've still not looked at the drum switch yet. Time is precious.

 

I'll get to it.

 

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I'm kind of guilty of getting it working but never finished too. I pinched an automatic lubricator from a moulding machine we were scrapping at work but never got around to fitting it and writing a macro to run it on the CNC mill. I also fitted a variable speed inverter to the motor and a motor RPM feedback back into the PC but never got around to connecting the two together so that the G-code can control the spindle. And as for the wiring, best the door is kept closed to the panel :lol:

Looks like your getting on well with the lather though, getting some nice work done on it. 

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I think the next job will be to make some wheel spacers.

The disks on the lightweight are thicker than the drums, so the rear wheels are a few mm further inboard than the front.

I think I'll turn down some old drums to shim the wheels out. A few mm. I've already got longer studs, so it will be fine.

 

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  • 3 months later...

Bugger.

 

I think my lathe motor has died.  I was trying to turn some seal press tools, in Ali, and the motor just stopped. It tripped it's internal trip.

Resetting the trip just produced the 'errmm' noise of a motor that just couldn't be bothered.

Where's good for reliable motors?

 

3kw, 1ph 1400 rpm.

 

Damn.

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