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sco
06-05-2012, 11:17 PM
Anybody got any tips or tricks for this? I've been mounting a dti on the bed and indicating off the side of the top slide as I move the saddle a set amount. From the saddle movement and the dti deflection I can then calculate the angle but it's tedious in the extreme to have to keep tweaking the angle and re-measuring.

Anybody got a better method, cheers,
Simon.

lane
06-05-2012, 11:29 PM
Use a sine bar. Set sine bar to correct angle and indicate the compound to it. most accurate way to do it.

TGTool
06-06-2012, 12:44 AM
Use a sine bar. Set sine bar to correct angle and indicate the compound to it. most accurate way to do it.

That's the way I do it too, but it's still tedious. It helps a little to watch the indicator and making a mental note of how much it moves as you tap the compound around. Then see how much you've gained on the error. It's still an iterative process but you can get some measure of proportion with a little thought.

oldtiffie
06-06-2012, 02:46 AM
Use a good protractor - vernier or digital - and perhaps a bevel guage - set the side of the top slide to/from the face of the chuck (which is square to the head-stock spindle axis).

Protractors are calibrated to 0.10 degrees (6 minutes) which has a rise of 1 in 573 or about 0.002" per inch.

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_setting/Lathe_angle_set9.jpg

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_setting/Lathe_angle_set10.jpg

Of course you can set the bevel guage or the protractor with a sine bar on a surface plate which is much easier and more accurate if you wish.

After the original setting the angle of the top slide can be "fine tuned" with a good (0.001"/0.01mm (~ 0.0004")) dial indicator.

sco
06-06-2012, 08:48 AM
Thanks for all the replies, I think a sine bar plus height gauges might be quite fiddly layed on it's side to set the angle so would have to be used with a bevel gauge.

I did find this old post which seems to be what I'm looking for; http://bbs.homeshopmachinist.net/showthread.php?t=25152

So I might have a go at making one, as an alternative what do people reckon to these devices; http://www.machine-dro.co.uk/digital-angle-finder.html - are they any good or a bit cheap and nasty.

Background to needing to set the top slide angle was for machining an ER collet holder.

dp
06-06-2012, 10:38 AM
Thanks for all the replies, I think a sine bar plus height gauges might be quite fiddly layed on it's side to set the angle so would have to be used with a bevel gauge.

Use a small locking sine plate. Set it up on your surface plate, lock it, then take it to the lathe.

http://www.amazon.com/Sine-Bars-2-Plate/dp/B004KAH1O4

bob ward
06-06-2012, 11:39 AM
A lathe chuck mounted sine bar could be the way to go. I made one a while ago and find it very useful for setting small angles eg morse taper, ER, NT30.

Once I have set the sine bar, I put a mill parallel of the appropriate width against the bar, set the block against the parallel, then clamp the block. Easy.

http://madmodder.net/index.php?topic=6839.0

justanengineer
06-06-2012, 01:27 PM
Maybe I'm the only clueless one on this, but what exactly are you trying to do?

Typically, if youre trying to get <1 degree angularity on the compound, there is a tapered fit involved in which case the angle in reality doesnt matter. What really matters is the fit to the mating part in which case you need to get out the blueing.

Arthur.Marks
06-06-2012, 01:29 PM
Use a small locking sine plate. Set it up on your surface plate, lock it, then take it to the lathe.

http://www.amazon.com/Sine-Bars-2-Plate/dp/B004KAH1O4
Locking? Never heard of such a thing. Your link looks like a normal sine bar to me :confused:

sco
06-06-2012, 01:36 PM
Reason for wanting to set the top slide accurately was to machine an ER collet chuck - bought a cheap Chinese one which when installed in the headstock had a runout of ~0.1mm measured on an endmill which I thought was excessive. I skimmed up the 8degree collet mounting taper in the main body and the 30degree taper in the nut and got the runout to 0.03mm which I thought was quite good. The skimming took minutes, setting the two angles took hours!

KEJR
06-06-2012, 01:58 PM
Use a sine bar. Set sine bar to correct angle and indicate the compound to it. most accurate way to do it.

How do you get the sine bar perfectly perpendicular to the axis of rotation of the spindle? Maybe if you had a precision faceplate with zero runout on its face, I suppose and you clocked the sine bar perfectly square, but it sounds like alot of error considering his application.

I'd think to turn a piece of stock in the chuck or collet with a good finish and put an indicator in the toolholder. then put another indicator inline with the compound to measure travel and do the trigonometry (I think this is what you did?). I'd use as much travel as I could to try and reduce errors of reading the DTI (I'd say a good 1/4 to 1/2 inch would be OK).

It sounds tedious, but I'd think that unless you can chuck up a cone or funnel with the exact angle and get it running out nice in your spindle you are stuck with indicators.

I'm wanting to see a way to use the sine bar here, but how do you make sure it is perpendicular? Do you turn a piece in the lathe and then block up the sine bar and hold it against that trued up piece? I can maybe see htis working nice.

KEJR

moe1942
06-06-2012, 02:07 PM
Once you get it set mark it with a witness mark so you can go back to the same place without the hassle..

TGTool
06-06-2012, 03:14 PM
I'm wanting to see a way to use the sine bar here, but how do you make sure it is perpendicular? Do you turn a piece in the lathe and then block up the sine bar and hold it against that trued up piece? I can maybe see htis working nice.

KEJR

Bob Ward has a link to at least one setup for sine bar use. I did nominally the same thing, making this tray to hold the sine bar with a back rail that can be adjusted to be straight with the ways.

http://i48.photobucket.com/albums/f244/TGTool/P1010352.jpg

The back rail is spring loaded with an adjustment screw so it's quick to get it zeroed out with the indicator on the carriage. The shank or handle for the tray can go in the spindle taper or just be gripped by the chuck.

Once the rail is zeroed then the sine bar is indicated from the compound travel. Still a little fiddly to get set since there's no corresponding adjusting screw for the compound angle - just tap and check. Maybe that should be my next project.

http://i48.photobucket.com/albums/f244/TGTool/P1010348.jpg

You do need something this accurate to get ER collet cavities done right. If you accept as much as a thousandth movement of the indicator as good enough, it translates into two thousandths error at the front or back of the collet and your stock will be all over the place. I've made quite a few ER adapters so I've visited the pitfalls.

dp
06-06-2012, 03:43 PM
Locking? Never heard of such a thing. Your link looks like a normal sine bar to me :confused:

Wrong link! :( I'll find it again.

Short on time and can't find the original, but I found a 1" wide version of one of these:

http://www.precisiontoolgrinding.com/images/sine%20plates.jpg

Mcgyver
06-06-2012, 04:32 PM
I did nominally the same thing, making this tray to hold the sine bar with a back rail that can be adjusted to be straight with the ways.

that is a clever enhancment.....with it the build can be simplicity itself with little care to accuracy....all you need is 'flat', your 'adjust true' fence and a way to chuck it. Good stuff

sco
06-06-2012, 05:23 PM
Thanks TG - that looks a neat setup. In the meantime I've refined my original method making it much quicker - basically position the dti on the top slide so that at one end of the saddle sweep the point lies on the axis of rotation of the slide. In this way rotating the top slide has a small effect on the dti at one end of the sweep and a maximum effect at the other end - makes it much quicker to iterate to the correct reading. Picture would help to explain - I'll take one if anyone is interested.

Thanks all,

Simon

Arthur.Marks
06-06-2012, 07:03 PM
Short on time and can't find the original, but I found a 1" wide version of one of these:

http://www.precisiontoolgrinding.com/images/sine%20plates.jpg
Thank you, dp. I'd never seen that feature before. It looks practical for specific setups. Mental note... file away for when later needed :D

Toolguy
06-06-2012, 07:33 PM
I just put the dial indicator (1" travel dial) on a rod in the chuck or collet and set it against the side of the top slide. Then zero the Trav-a-dial for the carriage. Then run the carriage an inch or two or four, whatever I figured for the triangle. The long side is the carriage travel, the hypotenuse is the compound slide and the short side is the indicator reading. It is a simple matter to level out the indicator by turning the spindle and get it parallel to the cross slide by visually comparing it to the edge. This is not quite the accuracy of the sine bar methods above, but pretty close.

lane
06-06-2012, 09:49 PM
How do you get the sine bar perfectly perpendicular to the axis of rotation of the spindle? Maybe if you had a precision faceplate with zero runout on its face, I suppose and you clocked the sine bar perfectly square, but it sounds like alot of error considering his application.

I'd think to turn a piece of stock in the chuck or collet with a good finish and put an indicator in the toolholder. then put another indicator inline with the compound to measure travel and do the trigonometry (I think this is what you did?). I'd use as much travel as I could to try and reduce errors of reading the DTI (I'd say a good 1/4 to 1/2 inch would be OK).

It sounds tedious, but I'd think that unless you can chuck up a cone or funnel with the exact angle and get it running out nice in your spindle you are stuck with indicators.

I'm wanting to see a way to use the sine bar here, but how do you make sure it is perpendicular? Do you turn a piece in the lathe and then block up the sine bar and hold it against that trued up piece? I can maybe see htis working nice.

KEJR


Mine has a V grove on the bottom clamp it to the shaft you are working on and roll the chuck until the flat side of the sine bar is parallel ,then indicate the angle in. You can also clamp the sine bar to the extended ram of the tail stock and do the same thing.

Rich Carlstedt
06-07-2012, 11:40 AM
I think I am missing something.
If you want an angle that is easy to set up, Take your tool slide off, and grind or mill it parrallel to the toolslide positive way ( which is always the headstock side )

I did this to my Boxford Lathe a number of years ago as can be seen in this photo.

http://i273.photobucket.com/albums/jj220/StationarySteam/Shop%20tales/P6070001.jpg

Use a sine bar or protractor from this accurate finished surface to the work piece, or your chuck

Remember on any taper turning, tool height is critical for getting accurate tapers

Rich

PS
It is also easy to clamp a flat (ground !) plate ( say .5" x 4 x 4 ) to the ground surface and that brings you upto turning center height
for measuring against the work

TG- Nice tool !

Carld
06-07-2012, 12:50 PM
I have honest questions and want honest answers.

How many times do you need to set the compound to within a minute or a second of a degree?

What are you making that requires such degree of accuracy?

Do you do that every time you move the compound?

Have you checked the marks on your lathe to see if they are accurate to +/- 1 degree and isn't that good enough for general work?

dp
06-07-2012, 01:05 PM
How do you get the sine bar perfectly perpendicular to the axis of rotation of the spindle?

I use the locked ram of my tailstock for the reference surface. My chuck is too small to work effectively for a reference except for aligning the QCTP.

Mcgyver
06-07-2012, 01:23 PM
How many times do you need to set the compound to within a minute or a second of a degree?


any time you make a machine taper.

Personally I've never done so using the compound. I use the compound for quick and dirty stuff like including turning insitu centres in the three jaw. I use the taper attachment for machine tool tapers. Obviously not every lathe has a taper attachment so anyone cutting machine tapers with the compound will have to figure out how to set it. I did a lot a more machine tapers way back when than I need to now, it was a crappy process....indicate an existing taper, do a trial cut and either check with blue or a sine bar, rinse, repeat.

A simple device that expands shop capabilities like that pictured on the previous page makes it into the 'thats neat' category regardless of how frequently its used....because when you do make a machine taper it looks like it will save a lot of frustration and time.


What are you making that requires such degree of accuracy?

any machine taper, in the case of this thread, its an ER collect chuck

justanengineer
06-07-2012, 01:54 PM
any time you make a machine taper.

Personally I've never done so using the compound. I use the compound for quick and dirty stuff like including turning insitu centres in the three jaw. I use the taper attachment for machine tool tapers.

I do the same. I use the taper attachment, but I also then blue the part and check with a known good taper socket as I do not want to ruin another taper (seen it in too many damaged spindles) by forcing one Ive made into it, or worse yet damage something bc an improper taper let go of a tool.

Personally, I dont see the need to use (and wouldnt as they will introduce inaccuracy) sine bars or any other jigs to set a compound's angle. I would simply use an indicator on the compound and measure deviation from a known good taper in the lathe spindle. Take your cuts, then blue the new part and compare it to a known good reference part. If its off, break out the emery paper...

Mcgyver
06-07-2012, 02:07 PM
what introduces in accuracies is indicating existing tapers.....they are often much shorter than a sine bar and the indicator point has to be dead on centre height for that to work.

the tool TGT shows would be far more accurate than indicating a taper...the sine bar introduces error? :confused: sine bar and guage blocks is the most accurate way to set or measure an angle. this cutting, blueing, adjusting, repeating is the pita that tool is intended to eliminate

Carld
06-07-2012, 10:02 PM
And I will venture that even when you set the compound with the sine bar tool shown in one post you will still have to tweak the compound to get it right. The point is, and what I do, why not set it to the nearest angle you seek marked on the compound and then tweak it? Why spend a lot of time with the sine bar accessory and dial indicator and then do it again with the sample part.

It just seems like a way to take longer to do a job but I realize that is the goal of many home machinists.

Even if you don't have a sample part to double check the setting at some point your going to have to use some method to be sure the taper is correct. To me, anything you do on the front end as a setup has to be verified for the final cuts to finish to the correct taper.

What I am saying is the sine bar method or nearest angle method is only a starting point at best. From there you must measure the taper in inches of travel on the work piece to get it right.

I use a universal bevel protractor to set the starting angle if I don't trust the marks on my lathe. From there is a cut and try to finish to size.

TGTool
06-07-2012, 11:47 PM
Carld,

Keep doing what you're doing if it makes you happy, but I'm telling you from long experience that careful work with a sine bar will make the part right without more adjust-and-try. When I've adjusted the compound with a sine bar I can depend on the cut fitting the collet. I do a check with marking compound to verify but I don't have to go back and tweak the angle because the sine setup was only approximate.

It's also used in tool and die work where one part has to fit a multitude of others. A mold insert has to fit the other inserts without gaps and flash and the molded part has to fit whatever the final assembly is. You'd be bounced out of the toolroom if your approach to parts was cut, check, adjust, cut some more, check again. It's wasteful of time and material and doesn't produce the quality expected. Of course toolmakers make mistakes, but the goal is careful setup and making the part right the first time.

Carld
06-08-2012, 12:52 AM
Actually I never have and never would apply for a tool room job. It's just not my cup of tea. I prefer job shop work.

oldtiffie
06-08-2012, 05:53 AM
Too many are assuming that the (reference) side of the top-slide that they rest the sin-bar or what-ever on is parallel to the top-slide dove-tail axis to the same or similar order of accuracy as that of a/the sine bar.

It may not be - but even if it is, how would you know?

sco
06-08-2012, 06:06 AM
Too many are assuming that the (reference) side of the top-slide that they rest the sin-bar or what-ever on is parallel to the top-slide dove-tail axis to the same or similar order of accuracy as that of a/the sine bar.

It may not be - but even if it is, how would you know?

Good point - I proved this wasn't an issue by winding the top slide from one end of it's travel to the other with the dti resting on the reference side - the dti did no nore than 'flicker'. I think this proves the dove-tail axis is parallel to the top slide side.

oldtiffie
06-08-2012, 06:24 AM
Right on.

But some lathes do not have an adequate "reference side/face" - what then?

Is there a universal answer?

Mcgyver
06-08-2012, 09:38 AM
It just seems like a way to take longer to do a job but I realize that is the goal of many home machinists.
.

you think that is the goal? Sounds a lot like you attempting an insult - why? I may not get it right and inadvertently take longer to do something but to say its the goal is ridiculous.

1st off, this isn't a job so there is no delineation between 'job shop' and 'tool room' work. Its the hardly the case where if you have a B&S taper to do you call your buddy who is more into the tool room hobby work than the jobbing hobby work. :rolleyes: We do whatever needs doing and lots of hobby guys make tooling even if you don't.

Secondly, I doubt you are right that it is shorter to to do the bluing and iteration process. Curious why you think so...it's a process that can take some time whereas I can see this just nailing right off the bat. Oh and it also works with the taper attachment too so don't assume it's just the compound.


Even if you don't have a sample part to double check the setting at some point your going to have to use some method to be sure the taper is correct. To me, anything you do on the front end as a setup has to be verified for the final cuts to finish to the correct taper.

What I am saying is the sine bar method or nearest angle method is only a starting point at best. From there you must measure the taper in inches of travel on the work piece to get it right.


and how is that accomplished? sinebar and gauge blocks. I'm just not seeing how applying the same accuracy to the setup in the first place is either inadequate or a waste. But I haven't used one (nor have you) so I defer to those who have - how well do these taper setting devices work? Are you able to get a good tape fit without all the fidgety adjustment steps?

dp
06-08-2012, 10:52 AM
Too many are assuming that the (reference) side of the top-slide that they rest the sin-bar or what-ever on is parallel to the top-slide dove-tail axis to the same or similar order of accuracy as that of a/the sine bar.

It may not be - but even if it is, how would you know?


I know that when I got my lathe verifying the cross slide was one of the first steps I performed. While it probably should not be considered a given, it does seem a reflexive thing to do with a lathe very early on.

rohart
06-08-2012, 08:03 PM
When my main lathe was a plain Lorch - plain meaning no saddle - I had to do this frequently.

I mounted a small laser module in an ally holder, and glued on two mini magnets. WHen I wanted to set the top slide, I would attach the laser to the slide and point it at a large scale at the end of the woprkshop, ten feet away.

I degree was about three inches on this scale. I could get the slide to a sixteenth of a degree with no sweat at all. All it did was show up the slop in the top slide pivot.

oldtiffie
06-08-2012, 08:15 PM
Originally Posted by oldtiffie

Too many are assuming that the (reference) side of the top-slide that they rest the sin-bar or what-ever on is parallel to the top-slide dove-tail axis to the same or similar order of accuracy as that of a/the sine bar.

It may not be - but even if it is, how would you know?


I know that when I got my lathe verifying the cross slide was one of the first steps I performed. While it probably should not be considered a given, it does seem a reflexive thing to do with a lathe very early on.

Dennis,

I have the same lathe as you do as it seems do quite a few Canadians. Its a good small light lathe.

Here is a sketch that I did some time ago of verification of the perpendicularity of the cross slide to the lathe spindle head-stock.

It should be self-explanatory.

All the tools required should be in most shops:

http://i200.photobucket.com/albums/aa294/oldtiffie/Sketches/Face-platecheck1.jpg

oldtiffie
06-08-2012, 08:19 PM
Originally Posted by KEJR

How do you get the sine bar perfectly perpendicular to the axis of rotation of the spindle?


I use the locked ram of my tailstock for the reference surface. My chuck is too small to work effectively for a reference except for aligning the QCTP.

That should do it provided that the tail-stock and its quill are locked/clamped and an indicator on the quill reqistered no movement when the carriage is traversed along the bed. If that is the case the quill is parallel to the lathe bed and able to be used as a reference face.

Frank Ford
06-08-2012, 09:02 PM
I have a system that works for me. Once I made up the holder for my sine bar, I was able to cut accurate tapers by indexing against the locked tailstock ram, simply gripping the entire assembly together with one hand as I locked down the compound with the other:

http://www.frets.com/HomeShopTech/Tooling/LatheSineFixture/sinefixture06.jpg

It's not the be-all end-all for accuracy, but I can make things like R8 tapers that fit well enough to work. Here's the full writeup on my little rig:

http://www.frets.com/HomeShopTech/Tooling/LatheSineFixture/sinefixture.html

oldtiffie
06-09-2012, 12:07 AM
Too many are assuming that the (reference) side of the top-slide that they rest the sin-bar or what-ever on is parallel to the top-slide dove-tail axis to the same or similar order of accuracy as that of a/the sine bar.

It may not be - but even if it is, how would you know?


Good point - I proved this wasn't an issue by winding the top slide from one end of it's travel to the other with the dti resting on the reference side - the dti did no nore than 'flicker'. I think this proves the dove-tail axis is parallel to the top slide side.


Right on.

But some lathes do not have an adequate "reference side/face" - what then?

Is there a universal answer?

The very simple answer is here:

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_setting/Lathe_angle_set13.jpg

Put a parallel strip in the lathe tool post and lightly tighten it. Set the top-slide scale on the cross slide to zero. Put an indicator on the parallel strip, zero the dial and run the top-slide through it limits. Adjust the parallel strip so that there is no deflection of the dial as the top-slide is run fron end to end.

The face of the parallel strip is now accurately aligned to the axis of the top-slide dove-tail axis.

Put the base of the dial indicator on the lathe bed and the dial on the parallel strip checked face.

Traverse the lathe carriage to run the indicator from end to end of the parallel strip.

Adjust the compound (but not the tool post or parallel strip) until the dial fluctuation is zero as it moves from end to end of the parallel strip.

The parallel strip and the top-slide dove-tail axis are both now accurately parallel to the lathe bed axis.

Check the top-slide to compound circular scale is zero - if not re-mark it.

Carld
06-09-2012, 12:15 AM
I too checked to see if the sides of the cross slide were perpendicular to the axis of the spindle and they are only off the concave effect of the cross slide face cut. I also checked the angle marks on the compound setting and they are very very close.

I don't blue, test and cut. If I have a sample male taper I use a dial indicator along the side to set the compound angle. For a female taper I use the inside to set the compound. If the dial indicator shows "0" then the angle setting is correct. It's just like running it along a sine bar. When the taper is cut you should check it by bluing it and rubbing it in the socket and you may have to lap it in or dress the high spots some way. It's hard to cut a near perfect taper on most home shop equipment.

Originally Posted by Carld
It just seems like a way to take longer to do a job but I realize that is the goal of many home machinists.
.
Mcgyver said,
you think that is the goal? Sounds a lot like you attempting an insult - why? I may not get it right and inadvertently take longer to do something but to say its the goal is ridiculous.

Not an insult at all, just an observation. From reading the threads most home machinists would rather take time doing setups because they enjoy working in the shop and they are in no hurry. I'd rather just get it done and do something else. I guess it's a throw back to working in job shops.

Actually the tail stock quill may not be in alignment with the axis of the spindle due to wear on the quill and the bore it's in. Most tail stock quills have a little movement in them which may be a degree or more off axis, especially when extended. If I were to make such a sine bar tool I would use the ways as a guide to be in alignment with the spindle axis. Of course that assumes the spindle is in line with the bed ways.

I just have a hard time believing the sine bar taper setting tool will cut a near perfect taper every time any more than my way does.

oldtiffie
06-09-2012, 06:07 AM
Here is a solution that I've used for quite a while.

http://i200.photobucket.com/albums/aa294/oldtiffie/Sketches/Angle-set_accessory1.jpg

It is made from scrap (I prefer aluminium or brass) and is machined on a rotary table - the final/"spring" cut is "climb-milled".

It will be as accurate as your rotary table - my 6" "Vertex" rotary tables are calibrated to 20 arc minutes (1/180 of a degree) and is correct to 0.000097 " per inch or 0.0001" per inch which is 1 in 10,000.

There are no slip guages or sine bars needed but the accuracy is of the order of a sine bar - and no awkward convolutions either.

It works for internal and external tapers.

Set the accessory/tool up in the tool post.

Set one face ("A" or "B") parallel to the top-slide dove-tail as before.

Swing the top-slide and set the same face parallel to the lathe bed as before.

Now swing the top-slide and set the other face ("A" or "B") parallel to the lathe bed axis.

The lathe is now accurately set up for turning the required taper.

Mcgyver
06-09-2012, 09:16 AM
I just have a hard time believing the sine bar taper setting tool will cut a near perfect taper every time any more than my way does.

Thats the real question, if it does its a wonderful thing, if not and you have still do the iterations why bother.

Lots of credible guys have built them.....so how well do they work?

dp
06-10-2012, 12:50 AM
Actually the tail stock quill may not be in alignment with the axis of the spindle due to wear on the quill and the bore it's in.

Quite so - but if that is something one does not already know about their lathe then the idea of turning a taper with any precision at all is probably wishful thinking. These kinds of errors should be known to the lathe owner and corrected if possible if they are interested in high precision and repeatability.

But it does not mean that the sine bar cannot be used - it simply means the error has to be included in the sine bar setting.

One can also use the sine bar to set the cross slide angle and then use your method to verify! These are not exclusive operations - you can have it both ways.

oldtiffie
06-10-2012, 01:57 AM
So far all I see is how to set up presuming to use a lathe tool.

While the angle turned may be accurate enough, the real requirement for a good class of fit is surface finish. Any undue "highs" and "lows" will reduce the contact area of the taper mating faces.

The better solution is to keep using the same top slide angle set up, rough it by turnng it and finish off with a reasonable tool-post grinder. Or use the old fall-back of a fine single-cut file and "wet and dry" rubbing/cutting paper.

Final "tweeking" of the angle can be done with a good (0.001"/0.01mm) dial indicator on the rear and side of the top-slide.

http://i200.photobucket.com/albums/aa294/oldtiffie/Lathe_setting/Lathe_angle_set14.jpg