25.4_mechanic
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Will check in a sec ...
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Will check in a sec ...
JMS1972
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You can dial out runout with a 4 jaw chuck with independent jaws. It takes some skill and practice though.
25.4_mechanic
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I don't know why I didn't think of this myself again ...
Measured like this, there was nothing to see on the hundredths clock, on the thousandths clock, the shaft runs within 1.5 thousandths.
Then quickly clamped my small self-centering four-jaw chuck:
Error halved compared to the three-jaw chuck!
What do I do now with the three-jaw chuck?
A proper independent Burnered - albeit nicely somewhat older - four-jaw chuck is on its way to me ....
- Bring the machine in balance?
- Leave the bearing as is, at most get the shims a little more homogeneous on a whetstone?
- Prepare the 1" test rod between tips?
- Waiting for the four-jaw chuck?
Anything else?
Thanks!
Carsten
--
brightspark
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the same as any other 3 jaw chuck if your turning down metal. the 1st cut you make and your job will be accurate it just means you cant take it out of chuck and put it back in if needed you can only do that if you use an independent 4 jaw chuck and not a self centering one
25.4_mechanic
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brightspark
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build it back up and set the bed up using and turning a test bar
25.4_mechanic
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I also noticed this irregularity towards the bed, and it corresponds with the somewhat thinner shims there.
I have just driven with loosened belt and without upper bearing shell the shaft manually on the bullgear - then put on the upper bearing shell and tightened - but not as ox-firm as they were - and again driven the shaft on the bullgear: I feel no difference in rotational resistance.
Given the values of the current shims ... I should still have 0.4mm feeler gauge material by the meter here (used to make LockPicks), that's uniformly strong stainless material, I should try it with that.
What do you think?
Thank you,
Carsten
--
brightspark
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shim it so it still runs freely and doesnt lock up when you tighten the screws down and there is no play on the bearing spindle
25.4_mechanic
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Found it 
Shims are secured
Carsten
--
Shims are secured
Carsten
--
JMS1972
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I'm glad your mandrel is roundI don't know why I didn't think of this myself again ...
View attachment 330491
Measured like this, there was nothing to see on the hundredths clock, on the thousandths clock, the shaft runs within 1.5 thousandths.
Then quickly clamped my small self-centering four-jaw chuck:
View attachment 330500
Error halved compared to the three-jaw chuck!
What do I do now with the three-jaw chuck?
A proper independent Burnered - albeit nicely somewhat older - four-jaw chuck is on its way to me ....
- Bring the machine in balance?
- Leave the bearing as is, at most get the shims a little more homogeneous on a whetstone?
- Prepare the 1" test rod between tips?
- Waiting for the four-jaw chuck?
Anything else?
Thanks!
Carsten
--
Personally I think you should put the original shims back in and run the lathe for a few weeks and get to know how to use it.
You will only need to add shims if the front bearing is getting hot.
It seems like you are getting distracted by chasing accuracy and it's taking all the fun out of owning a lathe.
Why not work through some of the projects in the Harold Hall book and get to know the lathes capabilities.
Good luck!
25.4_mechanic
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We both feel the same way.
That sounds very knowing - yes, the joy was a little clouded lately.
That's exactly the plan I have, I had already ordered the material for it on Saturday.
And even there I follow his advice: For projects use material with known properties, no longer the leftovers from the smith/scrapper.
In one point, however, the good Harold Hall is mistaken: When searching for his suggestion 230M07/EN1A, I find exclusively suppliers from the island, he was of the opinion that this designation had become internationally accepted ...
I then translated this into 9 S Mn 28 / 1.0715 and this is on its way to me in various dimensions. EDIT: I never intended to add shims, I just wanted shims with consistent thickness throughout. The machine is back in "found condition", albeit with the front main bearing not quite as tight.
A successful week to all
Carsten
--
prepman
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It's just that it's easier soldering cleanSometimes I think.......yes, that's about it
Active recirculating cooling is currently not in the planning stage, but the tray was nevertheless necessary, if only because of the total-loss lubrication of the two main spindle bearings.
The amount of oil that remains to be absorbed after the chips have been vacuumed out is still within the range of what the blue workshop tissues are capable of absorbing - this should be even more successful now that the machine has been raised.
The tray has become so luxuriously large that it should be quite easy to install a drain at a later date - if, say, there is a milling machine with a built-in circulation pump to the right of it ...
Thank you for thinking of this!
Have a wonderful sunday all,
Carsten
--
If your using a piece of ground stock in a 3 jaw then you are effectively checking the 'true' of the three jaws. To check the spindle then you need a morse taper shaft. You can produce this yourself. Put an oversize bar for MT2 in the 3 jaw chuck. It doesn't matter if the 3 jaw is out or not, If if was running a 10mm off then it would be awkward. Remember it is the axis of spindle you are checking which the lathe produces no matter what the chuck does. If you put a piece of square bar in the 4 jaw chuck and put at 10mm to one side, providing there's enough 'meat' it will still end up with a shaft parallel to the axis of the spindle.I don't know why I didn't think of this myself again ...
View attachment 330491
Measured like this, there was nothing to see on the hundredths clock, on the thousandths clock, the shaft runs within 1.5 thousandths.
Then quickly clamped my small self-centering four-jaw chuck:
View attachment 330500
Error halved compared to the three-jaw chuck!
What do I do now with the three-jaw chuck?
A proper independent Burnered - albeit nicely somewhat older - four-jaw chuck is on its way to me ....
- Bring the machine in balance?
- Leave the bearing as is, at most get the shims a little more homogeneous on a whetstone?
- Prepare the 1" test rod between tips?
- Waiting for the four-jaw chuck?
Anything else?
Thanks!
Carsten
--
Turn the end into an MT2 taper. For safety drill a tapped hole and fit a drawbar. Locate it in the spindle the minus chuck. Machine this up and check for taper. then you can make decision about the bearings.
Just make sure you're not trying to exceed the manufacturer's accuracy
25.4_mechanic
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I think with this advice you hit the core quite well, I sometimes have to tell myself that.
The good Mister Hall also gives - quite rightly - speeds, an area that I had previously only dealt with according to feeling.
But how should I calculate cutting speeds without knowing the speeds of my machine ....?
Yesterday I wanted to get to the bottom of it:
The fully mechanical hand tachometer developed a nasty gear noise
, so the break in style had to be done to measure electronically - but the trusty Shimpo is also a bit on the older side.Have a successful day
Carsten
--
slim_boy_fat
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I'd not forgotten this, weather's been atrocious.
Diameter of the threaded portion is 7.37mm [so...8mm?] but it struck me that your oiler(s) are different to mine and the thread pitch is likely to be different. In order to measure the pitch I'd need to remove them from the lathe, empty of oil, clean then measure.
I can/will if you desperately need to know pitch, but.....
prepman
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Do it by feel and gain experience. The bible on turning doesn't take into account the variable conditions of lathes. Use as reference. There so many variables, especially with insert tools.I think with this advice you hit the core quite well, I sometimes have to tell myself that.
The good Mister Hall also gives - quite rightly - speeds, an area that I had previously only dealt with according to feeling.
But how should I calculate cutting speeds without knowing the speeds of my machine ....?
Yesterday I wanted to get to the bottom of it:
View attachment 330685
The fully mechanical hand tachometer developed a nasty gear noise
View attachment 330687
Have a successful day
Carsten
--
25.4_mechanic
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You have my dispensation, my son! 
Given how different the two are, that probably wouldn't get us anywhere. Thank you in any case!
It's a great thing to be able to do it by feel, the method for the practitioner.However, I didn't know any of my speeds, where should the feeling come from?
You need a point of reference.For example: H.Hall writes in the first practice exercise in the book
something about trying out cutting depths of 1mm, 1.5mm and 2mm and that a good (small) lathe should be able to do more, "but in this exercise we stop at 2mm for the time being" ...
... I had never done that before, even 1mm seemed pretty daring to me, I had never gone beyond that before.
I have now tried the other levels .... and indeed: it works!
My little Myford cuts 2mm out of a 40mm St37 steel cylinder @300rpm~,
you can see that it has to do something and if I wanted more I would have to use the new belt that is already here, but .....What I'm saying is, my gut used to tell me to stop at much shallower depths of cut, now I know more because I've read ....
... I think it takes a fair amount of knowledge to be able to have the right feeling ...
A nice evening to you all
Carsten
--
25.4_mechanic
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Today little Myford showed that she is also able to mill.
This grooving cutter comes from one of the last tool rescues, but not from the big haul I showed Friday.
The cutter has its own MT2 taper with M10 female thread, for this I turned and cut a tie rod with M10 threads on the ends - I specifically resisted the temptation to just take a piece of threaded rod!
I had not reported the vertical slide with accessories as a new acquisition, certain features or their non-existence had to do with it, I then came to an agreement with the seller and there is nothing more to say about it.
I had prepared myself for a lot of noise and drama and was then pleasantly surprised that everything went off with complete ease and effortlessness - perhaps precisely because I had expected drama and had invested corresponding thought and care ...
Along the way, I also learned to use softpacking.
I am very happy about this result - of course this is no substitute for a milling machine ..... Have a nice evening
Carsten
--
25.4_mechanic
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