Hafco AL900A lathe, is anyone able to identify what it really is?

Doug, your peep sight method is ingenious to say the least, I've never heard of being done that way but if it worked fine. The final test is does it turn parallel when a bar is not supported by the tailstock. that is the only true test.

I don't think you can say the original factory settings still existed on the lathe as it was not turning parallel. The correct settings are the ones that work. Adjusting the levelling feet will not make a great deal of difference, that is only for the final thou or so.

with the lathe as level as you can get it measuring on the bed surfaces even with a carpenters level, as long as it's true, will be good enough to start with. Then you have to square the headstock then the tail stock in that order. You can't use the tail stock as a reference if it is not correct.
 
Bob. Thanks for that, I did not realise the feet leveling was only a finale, I thought it was the basic adjustment and everything else was reliant on it.

So, tomorrow (providing there are no other tasks needing a higher priority) will put feet back to level with carpenter's level as everything is doubtless out of kilter now, will then do the turned point in the chuck , align headstock to tailstock then run tailstock to far end and peep sight it and see what that tells me. If that agrees will then try for parrellel turn.
I see on the web that I should have an old double edge razor blade to insert between the 2 centres as the most accurate way of aligning them. Hmmm, will need to do some digging to find one of those!

However, if moving tailstock to far end is out of line with peep sight, what then?

The ways look nice, I think (and hope) that they are straight.

I suppose another check would be to dismantle the carriage/saddle and check for anything weird out of sight.
But that really will be a last resort.

Regards
Doug
 
Bob. Thanks for that, I did not realise the feet leveling was only a finale, I thought it was the basic adjustment and everything else was reliant on it.

So, tomorrow (providing there are no other tasks needing a higher priority) will put feet back to level with carpenter's level as everything is doubtless out of kilter now, will then do the turned point in the chuck , align headstock to tailstock then run tailstock to far end and peep sight it and see what that tells me. If that agrees will then try for parrellel turn.
I see on the web that I should have an old double edge razor blade to insert between the 2 centres as the most accurate way of aligning them. Hmmm, will need to do some digging to find one of those!

However, if moving tailstock to far end is out of line with peep sight, what then?

The ways look nice, I think (and hope) that they are straight.

I suppose another check would be to dismantle the carriage/saddle and check for anything weird out of sight.
But that really will be a last resort.

Regards
Doug

Doug 1st. Rough lelvel is all you need to start.

2. Have you proved the headstock is square by turning parallel without the part supported in the tailstock that is the first test. Turn a piece as long as you can. It's no point proceeding until you have that.

3. now check the tailstock with a center point freshly machined in the chuck, adjust tailstock center to center. If you don't have a razor blade handy a piece of thin steel shim will work,, even a blade out of a box cutter will work, not quite as accurate, but close enough for this stage.

4. Now slide tailstock to the right and insert a test bar. with center pre drilled. You can start with a 1" cold rolled steel bar, or something better if you have it. Mount dial indicator on tool post or saddle, run indicator up and down length of bar should be close to parallel. Rotate bar 180 deg (roll chuck over by hand) confirm measurement is the same. If there is any error, from chuck to tailstock with indicator at tailstock end adjust tailstock to half the error, lock it and measure again. repeat until parallel to your requirements. Now for the proof, take a light cut from one end to the other, and measure with micrometer. make final adjustment as needed.

You can now test your peep sight if you wish, but you certainly don't need it here. And it just might be introducing an error.

Later down the track when your lathe castings have relaxed and you've acquired a better level you can fiddle with the levels but not really necessary unless you want to do toolroom quality work..
You only ever need the machine itself, a dial indicator and a level. to reset it if it ever gets out of whack, usually only after being moved, or a crash.

BTW the original factory settings were only ever valid in the factory, after it was shipped and relocated it should have been done again.

One other test you can do is place a largish piece in the chuck and face it, test with a straightedge for flat. this will confirm your saddle is square with the rest of the lathe.
 
Pierre thanks for the links.

Bob - I am still struggling with item 2 on your list. Doesn't seem to matter how much I turn the headstock, the damn thing still won't cut parallel!
Will keep at it tomorrow.
Am locking the carriage and using compound and cross slide only to eliminate any issues there may be with the carriage.
Headstock on mine has 4 locking cap screws and 2 adjusting cap screws. Both of the latter are on the motor side of the headstock. I am assuming there is a central pivot. Does that sound correct?

Regards
Doug
 
Doug, yes many or most lathes that I know of do have a central pivot. However not 100% sure if yours does. With the locking screws loosened set a dial indicator up to see if anything moves, then try the adjusting screws. hard to know what is going on without being there. can you take and post some pics. I know this is terribly frustrating, but it as to be done. Can you determine if the headstock is actually turning on its base as you adjust.. Can you grip a long bar in the chuck with some sticking out both ends, then try to move it by hand.

I don't think the carriage is your problem, don't worry about it, unless you have a specific reason to believe it's a problem. What we are trying to achieve is to get a line through the headstock to be parallel to the bed. The only way to achieve this is to rotate the headstock on its base, no other adjustment will fix it.
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Doug, yes many or most lathes that I know of do have a central pivot. However not 100% sure if yours does. With the locking screws loosened set a dial indicator up to see if anything moves, then try the adjusting screws. hard to know what is going on without being there. can you take and post some pics. I know this is terribly frustrating, but it as to be done. Can you determine if the headstock is actually turning on its base as you adjust.. Can you grip a long bar in the chuck with some sticking out both ends, then try to move it by hand.

I don't think the carriage is your problem, don't worry about it, unless you have a specific reason to believe it's a problem. What we are trying to achieve is to get a line through the headstock to be parallel to the bed. The only way to achieve this is to rotate the headstock on its base, no other adjustment will fix it.
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Doug, DO NOT use compound slide for this. Unlock carriage and use the long carriage feed, for your test cut. If you have long bar set in the chuck, you can set it up fairly well just by running a dial ind. mounted on the toolpost, run it up and down the length of the bar using carriage handwheel only, when you get it reading the same over the length, then take a test cut, for final adjustment.
 
Bob
Understood. I reverted to your method.
I had to move the headstock a surprising amount. It appeared to be very reluctant to do as told and each time when I tightened the locking cap screws it removed most of the gains but not by any predictable amount. So it was a very repetitive process.
Got it down to 1 thou out of parallel per inch over a 6" unsuported steel tube. Then 1 thou per inch over 18" of 2 1/2" alloy thick walled tube.
So very consistent.
Then trued tailstock to headstock centre to centre using razor blade. See Photo.
20180628_110141.jpg


Now for the big question, is 1 thou per inch out of parallel acceptable?
If am very wary of fiddling any more due to the amount of spring in the headstock. Any changes there are pure guess and hope as there is no consistency to the response especially with the amount of spring that seems to be in it when snugging down the locking cap screws.

Opinions please?
 
It is still too much, but now you know what to do and you can relax a bit. It would be better to achieve nearer to Zero across the whole length but it will take some time to do so. I would take a break and start to learn the machine and turn some small stuff and practice a while. Dial the rest in at your leisure but don’t wait too long.

Old computer printers are a good source of straight steel rods, some are ground only and some can have a high polish.
 
Pierre

Thanks for the advice. I will look for a broken printer and see if it has a suitable bar.

I do wonder if I am better off now to wait for summer. A soaking 45°C in February should allow everything to relax and adjust to its new home?

Regards
Doug
 
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