My Harrison M400

[Munkul]

With 3 of us cleaning and refitting, we got on really well yesterday.
Back in place, levelled roughly on pads, and equal weight on all 4 corners.
We then cleaned up and fitted the 12" 4 jaw, and I clocked my test bar in... Some 75mm EN1A, 350mm long. It doesn't go through the chuck bore though I might have to turn it to 70mm just to get it inside the chuck bore and get that last little bit of rigidity.
Anyway I got one clean up pass made before I had to call it a night it felt like a different lathe to use, though!

 

[addjunkie]

And how parralel is the cut? Machine looks good.

 

[My Old Landy]

You have certainly made a fantastic job of bringing it back to life! Probably better than when it left the factory

 

[Munkul]

I can't say really... Of course I miked it before I left, I couldn't have walked away it was 0.04mm big on the free end. But that's one pass, on a bar that's not inside the chuck, with a worn insert, and there's bound to have been some spring in there. The bar itself looks rough, it was way too slow a surface speed and the insert would have wanted a bigger DOC.
Brian at Blue diamond told me to ring him up and he'll talk me through his exact method when I'm ready.
It'll probably be Tuesday or Wednesday before I get near it again though

 

[Munkul]

You have certainly made a fantastic job of bringing it back to life! Probably better than when it left the factory

Thanks for the kind words, don't worry I'm not thinking it's anything special, it's still an old Harrison lathe lol, warts and all! It'll just be an accurate old Harrison lathe
The likes of Scottmk1 and shox_dr, those guys made their lathes probably better than factory I'll settle for good enough...

 

[Munkul]

It’s going to be an impressive machine!

I’ve got my eye on a triumph of a similar size. Don’t particularly want a Colchester but you take what you can get.
Getting it out of the place will be interesting.

I can't believe the prices people are asking for Triumphs on ebay! It's the colchester name I think everyone knows.

 

[scottmk1]

Thanks for the kind words, don't worry I'm not thinking it's anything special, it's still an old Harrison lathe lol, warts and all! It'll just be an accurate old Harrison lathe
The likes of Scottmk1 and shox_dr, those guys made their lathes probably better than factory I'll settle for good enough...

Thanks, it looks like you are making a top job of yours as well, I'm sure it will do you proud.

 

[addjunkie]

I would suggest you use a harder better quality piece for your tests en1a is awful stuff to machine. Too soft.

 

[Munkul]

I would suggest you use a harder better quality piece for your tests en1a is awful stuff to machine. Too soft.

I did wonder... I looked about to find something better than plain mild steel black bar, and thought that EN1A would be fine... Could have went EN8 but thought that too hard would be bad too? It's what my steel merchant stocks. They stock the free machining leaded versions and in retrospect I should have got one of those instead.

 

[Hood]

EN8 or 19 would be my choice.

 

[pressbrake1]

Nice sharp hss tool that needs very little cutting pressure

 

[Hood]

Meant to say when I did the alignment of the big lathe (waste of time due to moving floor ) I relieved the bar in the middle by about 5mm so that I was only left with about 30mm to take skim cuts either end.

 

[Munkul]

Meant to say when I did the alignment of the big lathe (waste of time due to moving floor ) I relieved the bar in the middle by about 5mm so that I was only left with about 30mm to take skim cuts either end.

Yeah that's what Brian has advised me he's also said to sharpen the carbide if I can...or use HSS. I have some polished inserts so might try them, they're wickedly sharp and probably ideal for a shallow cut.

This week is actually quiet work-wise so after the early-week rush I should be able to make time and play with it, get to know it better, and get some roughing out of the middle. Might even get an hour or two tomorrow night. If I can't get a nice finish, I'll order some EN8.

I still have the 3jaw I got from @Hood to clean up, but for now obviously I'll stick with the 4jaw until I'm happy it's accurate. It's actually the first time in 10 years since college that I've actually used a 4 jaw and clocked something took me embarrassingly longer than it should have, to get it true, but it'll be 4 times easier next time

 

[Hood]

I used some nice sharp VBMT inserts they are what I normally use for finish pass on the CNC.

 

[Hood]

Regarding the 4 jaw, I rarely use them nowadays, only really for odd shapes. If needing accuracy then soft jaws are the way to go if at all possible

 

[addjunkie]

Itll machine round even if its not clocked spot on. And your error will show regardless.

 

[Munkul]

Itll machine round even if its not clocked spot on. And your error will show regardless.

Yeah I know just saying A fun experience which I suspect will get very old very quickly once I start using the machine for rough farmer work!

 

[addjunkie]

For rough farmer work your current error will be fine. But you need to get it better after spending whst I assume to be a fair chunk.

It would actually be a good time to fit a dro before you get it all completed

 

[Munkul]

For rough farmer work your current error will be fine. But you need to get it better after spending whst I assume to be a fair chunk.

It would actually be a good time to fit a dro before you get it all completed

Hence the test cuts now spent far too much on it to just throw it together and call it OK.

DRO kit will be ordered tomorrow. I was holding off on it until I at least got it back together. Imperial dials when trying to make metric parts is the worst! 1mm = 39 thou is easy... "need to take off 0.65mm diameter = 0.35mm DOC equals... erm... about 13 thou?" makes my head hurt, and I WILL make mistakes

 

[addjunkie]

Doesnt look old enough to be an imperial machine.