Align a Hole within Seconds using Lever Dial Indicator

[Ashish B]

Hi All,

I am Hereby suggested a Technique to find the Hole Centre within Seconds. Please Refer Attachments & also i need your Verdict on Error of Cosine Error.

(For all those friends who contributing in my previous thread "ALTERNATIVE TO SPINDLE PROBE", i really thank u all for your support but opted to start a Fresh Thread so as to avoid confusion & to address attention over the Main Problem which needs Debugging...)


Please Refer Attachments for the IDEA of finding hole with Spindle Orientation Command.

Ash.


Thanks for your TIME, PATIENCE & SUPPORT.

[DareBee]

I would probably give this a look. BUT...

YOU REALLY PISSED ME OFF BY SPAMMING OUR PM SYSTEM.

Shove it.

[Ashish B]

I am Sorry SIR. I truely apologize for the same.

The Sole Intention of doing so it to draw all the People of highest calibre to a Endeavour to align a Hole.


Sorry Sir

But Sir if you give a second thought over it, i hope u will get attracted to that IDEA & all the Barriers of Aligning Hole & we will forget all the Times when we used to sweep dial by hand to align hole.

Also i bet to get a improved Alignment Accuracy ( by 40 % ) by this Technique & need your valueable suggestions to filter out the Problem.

Ash

sORRY

[wildwestpat]

Hi Ash

1. Take a deep breath and think about the geometry between the rack (measuring axis of the DTI) and the probe tip. Your cosine error is obtained from the basic trig function where the cosine = the adjacent side / the hypotenuse of the imaginary right angle triangle. Hence if the angle of the probe is only a couple of degrees off there is virtually no error.

2. In the manual technique the measurement accuracy of the DTI is not important as it is only being used as a movement detector in an iterative process where the end result is the ideal of no movement on the DTI.

3. Most if not all CNC machine controllers have the facility for a touch sensing probe. The probe in its simplest form is only a bit of round stock - a battery - piece of wire and a crock clip. Cost if all items have to be purchased is well under $1 USD. The CNC software when instructed drives the probe into the hole wall stops when contact is made - reverses locates the oposite wall of the hole and centers that axis and repeats for the other axis. The action is similar to that used to set the home switch for machine refference.

For the above reasons the problem of centering a hole on a cnc machine probably does not exist in the real world and requires no skill on the part of the operator. The operation can be automatic if the work is always placed on the table in roughly the correct position with respect to the refference hole / probe sizes. Because the program can be arranged to select the sensing probe and plunge it into the hole and complete the centering action.

For the measurement of actual displacement for the reasons of the geometry at the probe tip the error will be small in terms of dead reckoning BUT this does NOT matter. Think of the error from indicated to actual as being some new unit of measurement say pears. Your DTI indicates a reading of 0.8 pear and you calculate that the center is half of that measured 0.8 /2=0.4 of a pear in from each edge in that axis. Repeating this in the other axis will center the hole but you are using pears as the unit of measurement.

I guess you have by now found that machinists don't like measuring if there is another way of getting the desired result. There have been too many problems in the past due to manufacturing parts in different place only to find that Fred's meter is not the same as Joe's and neither are correct compared to the international standard. Hence my previous comments about tolerancing and error spreads taking into account all the factors.

Hope this has satisfied your curiosity and that the topic can now be put to rest.

Kind regards

Pat

[Ashish B]

Hi...

I am really sorry to say that u can find a perfect example of mine WHEN U DRIVE URSELF CRAZY IN THE WRONG DIRECTION..

The technique expressed before does not work & the DTI probe ( as Pat suggested ) & sweeping the dial by 360 degree ( as all suggested ) is & is only the Method.

I apologize to spam everbody with this NONTECHNICAL / ILLOGICAL SOLUTION....


Ash

[wildwestpat]

Hi Ash

Don't think of it as the wrong direction just a detour. I think you have learnt a lot on the way and after all that is the purpose of the zone. an open mind is going to help you in the future provided you have a sound knowledge of the traditional methods used in engineering. For example the use of optical methods are likely to become practical in the near future as software developed for automated image analysis in the medical and astronomy become common place.

I am now bowing out of this discussion.

Regards

Pat

[Ashish B]