Some, but a bit limited I would say.  You should try to get hold of a copy of Connelly's book "Machine Tool Reconditioning" for a thorough run through on measuring machine tool run out etc.

I'd question the use of a tenths dial indicator away out on the end of an extended adjustable mag base stand like that, with the flexible fine adjustment in the middle of one arm too. And then it's mounted on the flimsy wheel guard (by machine tool standards) which could introduce unwanted movement of a thou or three.

Mag base might be better mounted on the column with dial gauge as close to tthe base as possible to minimise springy overhang.

Parallel stood on edge unsecured like that could be likely to move enough to influence reading too.

Then there is the question of what you are measuring. The ways the table runs on could be well low at one end and that dial could still read zero as it passes by the gauge finger. It will measure if the surface of the table is not parallel to the sliding way surface on the bottom of the table at that particular point, maybe, if it is not riding on other points further along the ways.

The best way to really accurately measure way wear is to strip the machine and measure the ways with micrometers, dial gauges mounted on suitable "sleds" or sliding bases and/or maybe straight edges and feeler gauges.

Probably a more practical way would be to set the gib strips by feel. Set them so they are shake free in the middle of the table's run then see if they get tight when the table is slide by hand to one end or the other. Or go the other way and set gibs shake free at one end and then see if there is slack in the more worn middle section.

Then you are probably better off to set a job up in the machine and take some trial cuts and measure the resulting thicknesses. A couple of test strips about the size of those parallels you have laid down flat would probably suffice.

Looks like a right handy piece of machinery for the workshop. Keep us posted on how it goes.

Edited By Hopper on 24/04/2020 03:01:30

And then there are the spindle bearings….

Measuring for tenths over 8 inches with a cheap parallel stood on a scruffy table adds to Hopper’s points of getting any serious measurements of any worth.

As he says a job of good length is likely to tell you more – after at least giving the table a good cleaning and stoning. It may not even be flat and level, so it may need grinding before any sensible conclusions can be drawn. How accurate do you want your finished jobs to be? Even beyond industrial use it may be good enough for the home hobbyist – ie better than a milled finish. Spindle bearings are likely the biggest headache if the machine has not been run ‘dry’.

I have used a lot of 540 machines, even with minimum care they are a good 30 year machine. The only one I can remember with a wear problem was on the cross slide which showed up on full width. I would put a systems cleaner in the hydraulic oil and run daily for a few hours after manually cleaning any blocked oilways. Change the oil then fit the mag chuck, grind the chuck when the machine is warm (leave it running with table moving for three hours) I doubt you will detect much if any wear in use for normal work.

Totally agree with Dusty, take a skim over the mag chuck and that will be as good as you will ever get regarding accuracy, you don’t say what accuracy you expect or what you intend grinding, are you looking for just a good finish, within a couple of tenths or are you looking to split the atom on it👍. When you grind the top of the mag chuck I was always told to do it with the magnets on, others say off, I wonder which way other members on this forum were taught, and reasons why.

Sort of, but may I take the opportunity to suggest measuring isn't a good way to start diagnosing unknown machine problems?

Trouble is precision measuring is easy to get wrong and liable to lead one deep into a contradictory maze. The pitfalls have been known to mislead experts. For example, using a tenths indicator on the end of a long boom is asking for trouble. It mixes measurement errors up randomly with any problem the machine might, or might not have. Unsafe to draw any conclusions from the results.

As first step I think it's much safer to test the machine by using it to cut metal. If it it performs properly, looking for trouble with a DTI is a waste of time! Conversely, If a machine doesn't cut properly, what's wrong with the cut should provide useful clues. Now is the time to get out the specification, DTI, and straight-edges etc. Precision measurements are invaluable for pinning down exactly what a known problem is and what needs to be done to fix it, precision is less effective, even dangerous, as an early indicator.

By analogy, most would test a prospective second-hand car purchase by taking it for a run round the block. At this stage failure to start, warning lights, weak brakes, slipping clutch, notchy gearbox, shrieking water-pump, noisy exhaust and oil in the road are all much more revealing than whipping the head off and carefully measuring the cylinder diameters for signs of wear!

Dave

It's very possible to have the machine so worn that it produces 'bent' parts and grinding the chuck will not fix that nor will the popular test of putting blocks on the corners of the chuck and grinding them to compare the thicknesses.

I had one of these and the cross axis ways were so worn that anything I ground was convex in the short axis. i did set about re-scraping it but after a lot of work lost heart and got rid of it, mostly because I didn't have a straight edge to fit the cross table ways (you can't fit a regular straight edge in there) and because the wear so so bad that the cross slide screw and nut were trying to carry the weight of the cross slide and table.

You can use your test to check for 'banana ways' but orientate the straight edge across the chuck and check that axis. If the ways are straight it will either indicated evenly along the length or have a gradual rise or fall on the dial. If they are as badly worn as mine the indicator will fall then rise showing a low reading in the middle.

Edited By Pete Rimmer on 24/04/2020 19:08:17

My only bit of advice is don't try to fix problems you don't have. Get the machine together grind the chuck, then grind a piece of steel making sure it at least 15mm thick. Thinner stuff can be pulled down onto the chuck and distorted giving false readings. If you then find problems they can be fixed as you will know what they are.

Since you are measuring with a tenths of a thou indicator, you are looking to be able to detect, accurately, differences of less mthan a tenth.

You cannot afford to have flexibility of anything near a tenth, so the DTI mounting must be as rigid as possible.

If there is any detectable flexibility, it will be difficult to tell if the deflection is ,wear (that you want to measure ) or flexibility which you can't; and don't want!

You can't measure accurately with a graduated bungee cord!

Howard.

Certainly look in a lot better nick than my little Herbert Junior when it arrived.

i don't know if you have a Facebook account , but there's an ongoing album here, which should be set to public viewing, each photo has a basic description of what I'm up to.
Eventually I'll duplicate the album to Flickr, and add some of the content on this forum, but obviously not on your thread.
The column itself was slightly bowed, as well as the main dovetails showing wear in the middles, so the knee rocked in two different dimensions.
The table showed the same banana tendencies, as do the cross slideways.
I could maybe have used it to grind a lens, thou it may not have been optically very good.