If you use that to launch a satellite, maybe the discrepancy would add up just saying
Machine Chuck stuck cx707
- Thread starter Theflyingwrench
- Start date
Machine
In hindsight, it was a good call. But it looks like the cause for celebration was premature.
I agree with @RobinHood. Leave things alone for now and figure out where you really are.
I'd advocate some more reading on this forum before doing anything else. You will find lots of threads on here about levelling a lathe / aligning a tailstock / aligning a spindle / concentricity, etc. You will quickly discover that levelling is not really levelling. That's just what much of the world calls it. If you conclude that it really is levelling, then I would submit that you have not read enough yet to be adequately confused
.As you may already know, I am not a fan of YouTube. Setting up a lathe properly, is something that gets totally messed up on YouTube all the time. Who do you trust? I'd hate to see you get led further astray by a flaky YouTube video.
Instead, I'd suggest browsing this forum to find good threads on the subject. You will find lots of debate, mistakes made, gallant efforts to fix problems, and lots of conflicting information. That is ok. Read it all anyhow. What it will do is inform you about all the ways folks mess this job up as well as learn about how they got resolved, what works, how opinions differ, and what the terms are. Taking short cuts will rob you of the opportunity to understand the complexity and the nuances of setting up a lathe.
For the purposes of getting going, I would suggest that you start your journey by understanding that not all lathes are fully adjustable and that the methods for setting them up vary by design and size of the machine.
If you have not already realized it from all the humour posted here, a tenth is probably not really a realistic goal. Especially not for non-adjustable lathes. For many of the smaller lathes, about all you easily do is align the tailstock.
That said, there are 3 primary goals you chase when you setup a lathe.
1. Measuring and attempting to remove bed twist and bed arch. (This is what is usually called Levelling.)
2. Aligning the tailstock.
3. Aligning the axis of the spindle with the axis of the bed.
There are others too, but these are the main ones. As I said above, not all lathes are adjustable for all three of these goals. But once you understand these 3 primary goals, you will be better equipped to decide what method(s) are best for you and your lathe based on reading the debate and discussion you find on here.
Let me just finish by saying that I have my preferred way of doing these things and others have their ways. Some are outright wrong, but most are just one fellow's opinion of what works for him. Personally, I don't think it's wise to jump into the middle of debates and discussions when your own lathe is on the operating table........ That's why I am deliberately avoiding telling you how I would do it if I were you. Instead I recommend you undertake to bring yourself up to speed and then come back here for the discussion. I (and many others) will happily engage in the debates at that time (and yes, there will be debate..... We do not all agree! LOL!)
Thought I would drop back in. If the lathe is level, put a dead centre in the tail stock, then see if one can be put in the head stock spindle with out removing the chuck. Remove chuck if need be, gently run tail stock up towards head stock, when tips of centres are close to touching, lock down tail stock. Carefully advance ram in tail stock to almost touch tips of centres together, this is where we see what shimming tail stock feet did!! Tips should line up from every angle viewed at 90 degrees to the bed of lathe. If tips don't line up, maybe remove all shims and see what happens. This gives a base line to work from. It does not indicate if bores of head stock and tail shock are parallel to each other or to the lathe bed. There is usually some way to move tail stock left and right. This adjustment is used to line up tail stock or to misaligne for cutting tapers.( longer then compound will do).
This still does not show you where the tail stock centre will be in relation to to head stock centre at the far end of lathe bed. Time for a test bar. Test bar length will depend on what is at hand, it has to able to support it own weight over the length you want to check. A 1/2in. or 12 mm. bar over a 6ft/2 m. length will not work well. And you should be able to easily handle it. It looks like this lathe is 36in. between centres. I would start with a piece about like you had, looks like 1in., but longer, maybe 18 in.
This is one way to line things up or see what you have. Put test bar in chuck, a 3 jaw will do for this, have enough material out of the jaws to turn end square and centre drill , 3/16 centre drill or so. Also machine O.D. of bar about 1/2 to 1in. This dia. is fairly important because you want the same dia. on the other end of the bar also. Turn bar end for end, machine and centre drill again. Do centre drilling and O.D. maching on end without moving bar, before turning for other end.
Put centres back in, support bar between centres. Do not put a lot of pressure on tail stock ram to support bar. Just a nice gently firm turn of the hand wheel, you want to be able to turn test bar with fingers. A tiny drop of oil wil help on each end. Don't use a live centre.( a variable). Now I hope you have a dial gauge. A sharp pointer would work, a sharp lathe bit. Put dial gage on/in tool holder, put probe end on machined O.D of bar, zero, gently turn bar, should stay at zero for full rotation. Now for the big one, pull probe back away from bar, Do not move cross slide or compound!! Move carriage to tail stock end of bar, put probe on this machined O.D. Do we still read zero, turn the bar gently, should read zero. Horrah, great, dam I like this lathe.
When we don't read zero, can we live with it, is it a tenth or 2, or?... Does the reading change when turning the bar? Not centre drilled on centre or burr, chip in taper ofcenter drilling. Ram abit loose, centre moving around in centre drilling. If the reading does not change when turning bar but is out anyway, tail stock may need to be moved sideways, Or,Or, tailstock could be low or high.
This does not show whether bore of head stock or tail stock are out of line with lathe bed.
For a giggle or 2, put dial gauge at centre of test bar, zero dial, unlock ram of tail stock, gently turn hand wheel tighter, did the needle move? depends on dia. of bar. Don't get the cheater pipe on the hand wheel. Put dial gauge probe on body of tail stock by the ram if possible. Put a bit of pressure on with hand wheel again, tail stock moveing a bit? While dial gauge is at centre of test bar, gently push bar back and forth by hand, any different readings? If you put the gauge against head stock body put some pressure on, if this moves life may be about to get interesting.
Another long story, and this is only the very basics.
This still does not show you where the tail stock centre will be in relation to to head stock centre at the far end of lathe bed. Time for a test bar. Test bar length will depend on what is at hand, it has to able to support it own weight over the length you want to check. A 1/2in. or 12 mm. bar over a 6ft/2 m. length will not work well. And you should be able to easily handle it. It looks like this lathe is 36in. between centres. I would start with a piece about like you had, looks like 1in., but longer, maybe 18 in.
This is one way to line things up or see what you have. Put test bar in chuck, a 3 jaw will do for this, have enough material out of the jaws to turn end square and centre drill , 3/16 centre drill or so. Also machine O.D. of bar about 1/2 to 1in. This dia. is fairly important because you want the same dia. on the other end of the bar also. Turn bar end for end, machine and centre drill again. Do centre drilling and O.D. maching on end without moving bar, before turning for other end.
Put centres back in, support bar between centres. Do not put a lot of pressure on tail stock ram to support bar. Just a nice gently firm turn of the hand wheel, you want to be able to turn test bar with fingers. A tiny drop of oil wil help on each end. Don't use a live centre.( a variable). Now I hope you have a dial gauge. A sharp pointer would work, a sharp lathe bit. Put dial gage on/in tool holder, put probe end on machined O.D of bar, zero, gently turn bar, should stay at zero for full rotation. Now for the big one, pull probe back away from bar, Do not move cross slide or compound!! Move carriage to tail stock end of bar, put probe on this machined O.D. Do we still read zero, turn the bar gently, should read zero. Horrah, great, dam I like this lathe.
When we don't read zero, can we live with it, is it a tenth or 2, or?... Does the reading change when turning the bar? Not centre drilled on centre or burr, chip in taper ofcenter drilling. Ram abit loose, centre moving around in centre drilling. If the reading does not change when turning bar but is out anyway, tail stock may need to be moved sideways, Or,Or, tailstock could be low or high.
This does not show whether bore of head stock or tail stock are out of line with lathe bed.
For a giggle or 2, put dial gauge at centre of test bar, zero dial, unlock ram of tail stock, gently turn hand wheel tighter, did the needle move? depends on dia. of bar. Don't get the cheater pipe on the hand wheel. Put dial gauge probe on body of tail stock by the ram if possible. Put a bit of pressure on with hand wheel again, tail stock moveing a bit? While dial gauge is at centre of test bar, gently push bar back and forth by hand, any different readings? If you put the gauge against head stock body put some pressure on, if this moves life may be about to get interesting.
Another long story, and this is only the very basics.
Susquatch has a very good point, my why is not better then anyone else's, it works for me until it does not. Many are happy with the way it works for what they are doing,the way it is. He was replying while I was still writing so I didn't see his reply until after I posted.
Do the basics first, put the powder in the pill before it's swallowed.
Do the basics first, put the powder in the pill before it's swallowed.