Cutting a window

==================== I don't know your overall sizes, but I have had good results using magnetic base dial drop indicators and ignoring the dials. I have three bases (2) 1 inch and (1) 2 inch indicators which I use on both the Emco lathe and mill. My eyes are starting to go and the dials are much easier to read. They also eliminate the backlash problem and can show you how much things shift when you tighten the clamps. Also is real eye opener when you lean on the machine.

Poor man's digital readout.

Uncle George

One of these days I will weaken and buy a couple of 2 inch (bigger if I can get cheap ones) plunge indicators to play around with this idea. Dumb question: where/how do you mount the indicators? Do you do anything special to protect them from chips and oil?

Bill

I wouldn't unlock, and relock. Instead, I would put a slight drag on each axis and leave it there while I make the cuts. Older mills especially will move quite a bit when you play with the locks.

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================== I find the standard jointed dial indicator holder to be minimally useful in this situation.

I have several indicators with the magnetic back. Use the for 2 of the axis and as a lathe "stop"

Also bought 2 of the mightymag holders -- use these to mount my 2 inch stroke holder. With a set of 123 blocks I can get good accuracy up to 5 inches which is all I ever needed so far.

No particular care taken to keep oil out but several indicators do have oil inside.

I use the PRC Enco indicators for this. Can't tell any difference between then and my B&S/Mitutoyo drop indicators except these feel a little more "gritty." Top quality indicators may be better in a production environment.

Watch the Enco sales fliers. Get the indicator/mightymag copy and a set of contact points for less than 15$. Your choice of black or white dial.

Uncle George

Thanks for the detail. Have you posted pictures of this anywhere? Please don't do so just on my account, but if you have gone to the trouble, I would enjoy seeing the setup.

I am by no means production oriented in the volume sense. The four clips are done, and that was a big run :) Two of them are pretty good; two more are more than useable but nothing to write home about. I just received a shipping notice that, among other things, tells me my stops are on the way. Too late for this batch, but I now have first hand understanding of why they are helpful.

Thanks!

Bill

I have used the dials as you do for years. Finally, about 5 years ago I bought the Shooting Star 2 axis DRO and installed in on my well worn mill. It has worked very well for me. Well worth the money. I just wish they had the new design when I got mine.

Pete Stanaitis

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F. George McDuffee wrote:

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See 3rd picture down at

Shows a magnetic back dial indicator for the mill Z "knee" and a mightymag for the table Y. Both drop indicators are PRC Encos. Test indicator is also an Enco 15-0-15 for general use, but I have a 0.0001 German made Maier test indicator for very accurate work.

I don't yet have all the pictures uploaded where I have the captions.

FWIW -- the upsidedown rear mounted cutoff [parting off] tool holder is a very worthwhile project.

Uncle George

George,

That's a nice page! Early on, I tried placing an on/off mag base on the flat(ter) portions of the base of my machine, without success. The base sticks, but it never sits flat so any readings would be questionable. The mighty mag clone you suggest is worth a shot. If nothing else, it would be nice to see how much my machine moves around when the locks are applied. So far, I suspect I get better results using them than not, but I appreciate your raising the question.

With the power feed in place, it is not super easy to feel the longitudinal gib resistance. At one point, I might have been having problems because the gib was not properly tensioned and not so much because I needed the locks. Since I need to remove the feed to get to the left oil port, I am trying to remember to note the gib resistance while it is removed.

I was envisioning a longitudinal indicator too. Is there any particular reason you do not use one in that direction?

Thanks!

Bill

You can also use "kentucky windage" and off-set the move when the clamp is tightened it will be to put the table/slide where it should be. V-way machines are much less prone to this than the round column "knee" that the Emco has.

I have not yet had occasion to try this but several people have told me of good results by applying a thin teflon or HDPE [high density polyethylene] based tape to the sliding surface of the gib and using only light/thin oil. See:

you try this let us know how it worked as I am sure many people are in the same situation.

============= Did not need micrometer location accuracy along that axis [X] [cutting slot] so did not put an indicator there. I have never had occassion to machine anything that required micrometer accuracy on all three axis at the same time.

If you think you may be doing this sort of thing extensively you may want to consider fabricating dial indicator holders and possibly modifying your table/slide [drill & tap] to mount the indicators/holders.

Uncle George

George,

My machine has a round column, but dovetail ways. Does that change anything?

If you try this let us know how it worked as I am sure many

Interesting. What is that intended to fix? Is the idea to give tighter fit with less wear? So far, I appear to fine as long as I have the gib properly adjusted, it just took me a while to realize the consequences of the obvious: one feels the feed more than the gib.

If any 31 Bestline feed users know of a good alignment proceedure, I am most interested. It seems to be aligned fairly well, but there is no doubt room to do a better job. I might buy a couple of machinist's jacks in hopes of holding it in place with the adpater loose. That would hopefully allow me to fiddle until the gears work as smoothly as possible, and then tighten the bolts w/o disturbing it. Comments? Better ideas?

Fair enough.

It was _not_ (!!!!) me, REALLY :) One of the old war stories in my general niche is that some well meaning dude took a drill to a high tech anesthesia machine. He wanted to mount something - simple, right? What he didn't know is that machine in question had manifolds integrated with the case. I did not hear whether the entire machine was scrapped, but it seems likely.

First, I will start with a mighty mag to see how it works out. Looking at the machine with your comments in mind, I might see how to do it w/o drilling. Before I drill, I would want to have evidence that the machine is flawed. So far, I still believe it is more accurate than its operator.

Thanks!!!!

Bill

-------------- They generally are .... Main reason for using the dial indicator is easier reading [which becomes more important the older you get] and elimination of the backlash problem. One concern on metric machines is when they kept the metric feed screw [or use someting other than a 10 or 20 TPI] and simply used a .001 inch graduation collar to produce an inch machine. Works fine for small moves but is a problem when you go "across" the division lines by moving more than one lead.

Uncle George