Electronic LED Edge Finder

[drhaasmach]

I just got an LED edge finder from msdiscount.com. Came with no instructions. It is metric and has the ball on the end. Anyone know the di. of the ball is. When i put it in the calipers i get 9.95mm. But anyone know the size the manufacture gives is it 10mm even? Its not the standard 0.4in
It is the metric one. Plz help if u own a metric one made my MEDA.

[Astonlee]

The vast majority of these edge finders are made in the far-east, and are a nominal Ø10mm, because they use purely as a simple edge finder so 0,05mm (0.0019685”) on diameter error really does not matter. If you are willing to spend a lot more $ you can go try something like these: http://www.mctooling.com/index/images/item569.htm

[Metal1cutter]

Well here we go..

Today I had to prove something to myself. I use an edge finder of the
style which has 3/8th shank and a .200" dia. end from L.S. Starrett.
I spin it about 1600 rpm and move into the work until it falls off
center. Pretty standard tool.


Anyhow I was under the impression that if the shank was running out it
would still find the edge. I mounted it in a collet with a piece of
thick paper stuffed in one side of the collet. The shank was really
running out. Well, it refound the edge within .0001" of the first
time. There! I proved it to myself.


Now! If you can be that sloppy and find the edge, to me that style is
a darn good design.


I am waving my arms around because I can't imagine how an operator can
think he's found an edge with an edge finder which has a light bulb in
it or one which makes a noise. The reason is because if it's not
rotating how does he know if it is concentric to the spindle axis?


One of my soap boxes. Let's hear the flack.. (grin)


Regards to you all,


Stanley Dornfeld (Originally posted on Alt.Machines.CNC News Group Jun 24 1999)

A following post: ***

Quote:
Originally Posted by Carl Darnell
Yep, they'll have to pry my spring type edge finder out of my cold dead hands. I have gotten good with it and it is very accurate IF you have a delicate touch on the handwheels.

Carl..,

You have certianly validated my position on this. Regards!

I've learned to sneak up to an edge and turned the "Tenth Knob" a little and then pause 2-3 seconds and see if the machine vibration will "Giggle" enough to move the table. If not, then proceed some more.

I can usually, if needed, hit +-.0002.

I guess I don't know the constraints the newer machines impose. But, I wouldn't want a machine I couldn't get into, to see what I was doing. I need to be in where the work is being done to do it correctly.

It seems Boris has done all he can to ensure his accuracy using the "eleccy" edge finder.

Though I tend to wonder, why one would do all that, when the L.S. Starrett edge finder does that all automatically even if it's running out a little?

Anyhow, we all do what we have to to make good parts. And hopefully, do so in a way we can go home and sleep at night. *s


Best regards to you all,

Stanley Dornfeld