Dial test indicator on a mill question.

[Parlo]

Does anyone ever need to set their indicator stylus not parallel to the spindle?

IMG_20220614_143413.jpg

drive.google.com

 

[woodchucker]

NO, not that way.
You can set it no parallel from the dial plane, but not the side of the body's plane.
For an accurate reading.

Now that being said... yes you can do what you showed for a relative reading, where you are just looking for movement of the pointer.
But for an actual reading of distance, NO.

 

[Parlo]

NO, not that way.
You can set it no parallel from the dial plane, but not the side of the body's plane.
For an accurate reading.

Now that being said... yes you can do what you showed for a relative reading, where you are just looking for movement of the pointer.
But for an actual reading of distance, NO.

Thanks for your reply, I agree 100%.
If I can expand on the subject a little further with a slightly different question.
Is there EVER A NEED to set an indicator where the stylus is not aligned with the spindle and the stylus travel is not directly towards the centreline of the spindle.

 

[woodchucker]

Thanks for your reply, I agree 100%.
If I can expand on the subject a little further with a slightly different question.
Is there EVER A NEED to set an indicator where the stylus is not aligned with the spindle and the stylus travel is not directly towards the centreline of the spindle.

well from what you are showing no.

But if the object were lets say an angle plate, and you already had something attached to it, and wanted to make sure it was sitting square to the base, you might need to reach in there like you show to get behind the other part so you can run the table up and down, or the quill up and down.
SO YES.

it's rare, it's against the rules, but rules are meant to be broken.
There are no absolutes in life except death. Everything dies eventually... at least every living thing that we know about.

 

[Larry$]

Not sure I understand the question. In use the contact tip must move in an arch about it's pivot. Otherwise you are likely to damage something. The contact arm is (usually??) mounted as a friction fit to the indicator so it can be positioned to odd angles to the rest of the indicator but again only about it's pivot point. The movement should be as close to tangential to the arch of the tip as possible to reduce cosine error. Only applies to actual lineal measuring not positional like sweeping a hole.

 

[Parlo]

Not sure I understand the question. In use the contact tip must move in an arch about it's pivot. Otherwise you are likely to damage something. The contact arm is (usually??) mounted as a friction fit to the indicator so it can be positioned to odd angles to the rest of the indicator but again only about it's pivot point. The movement should be as close to tangential to the arch of the tip as possible to reduce cosine error. Only applies to actual lineal measuring not positional like sweeping a hole.

Thanks Larry,
The specific research involves finding the centre of a small hole on a mill and the issue if the indicator not set vertically. Also the other issue that arises from the stylus not travelling directly towards the spindle centre (i.e. the indicator face not at a tangent with the spindle ).

 

[mmcmdl]

There are no absolutes in life except death.

And TAXES !

 

[Parlo]

well from what you are showing no.

But if the object were lets say an angle plate, and you already had something attached to it, and wanted to make sure it was sitting square to the base, you might need to reach in there like you show to get behind the other part so you can run the table up and down, or the quill up and down.
SO YES.

it's rare, it's against the rules, but rules are meant to be broken.
There are no absolutes in life except death. Everything dies eventually... at least every living thing that we know about.

I see, the part must be thicker than the 1/2 the diameter of the indicator to use at 90 degrees to the angle plate.

 

[woodchucker]

I see, the part must be thicker than the 1/2 the diameter of the indicator to use at 90 degrees to the angle plate.

no, you are showing the indicator running the face of the square, not the edge. The edge is square, the side is not.
so running the tip along the face would not be done for a square.. yes for an angle plate.
That tip can only register things in the swing of it, not things adjacent to it.

 

[woodchucker]

And TAXES !

not to get political.. but there are people who have never paid taxes for one reason or another.
medical ..
mental...
etc.. never worked a day in their life..

and more..