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modelman
12-07-2010, 10:38 AM
I use a "wiggler" for finding edges when I am milling and drilling holes but I can never get "dead on" spot. Wigglers depends on vision which I have a problem with. I have seen edge finders with lights that light up when the perfect edge is located. Do these work? Are they accurate? They are expensive but I don't mind spending the money if they work.

pugs
12-07-2010, 11:46 AM
The ball with lights systems do work (or pin or whatever style they have now), but they should be double checked for accuracy with an indicator every once in awhile. Read up on which ever one you think about buying as some use the part as the conductor to finish the circuit for the light going through the machine and back to the spindle. This means that they won't work to find edges on non magnetic part materials or possibly in machines with ceramic spindle bearings (probably not much of a problem on the manual stuff). I have seen a few of the lighted edge finders worked by detecting the ball or whatever moving off of a conductor in the body, these should work with plastic parts etc.

On my manual equipment I typically use a jump style edge finder. These can also be had in a jump and click style so that there is an audible clicking sound once the tip has jumped. I think there are also now some made that can "jump" farther than regular, so that it is easier to see as well.

The CNC equipment I have uses a renishaw probing system so I don't really get much use of the jump style. I don't own an electronic type edge finder, but did play with a couple in tech school and an old employer. The biggest problem I saw with the ball style electronic finder was you could get chips under the ball that would hold the ball off center a bit and then give you a bad reading. Easily overcome by making sure the area is clean of chips when used and keeping the edge finder nice and clean as well.

I have never used a wiggler, so not sure what is available for them.

steamer
12-07-2010, 11:52 AM
I get the Home Shop Machinist and in there latest issue there's an add for a laser edge finder. http://www.lasercenteredgefinder.com/main.html
Never used one myself but a machinist at work swears by them.
Rob

9W Monighan
12-07-2010, 11:57 AM
I use a Starrett edge finder and also have a Blake CoAx indicator for centering on bores and holes.

modelman
12-07-2010, 08:51 PM
On the jump style finders, you still have to watch when it goes off center-correct. The laser type depends on seeing the light at the edge or center point. I think the only one that would help me is this one-
http://www.victornet.com/alphabetic/Tool-Setup-Electronic-Finders/1606.html The model GAE-EF is the one I was looking at . Anyone familiar with this?

pugs
12-07-2010, 10:13 PM
That model is like one of the ones we had in tech school and it would not work on non conductive parts. IF all you do is steels, aluminum, brass etc then it should work fine, but plastics you have to cheat (read gage block that touches the vise).

Correct the jump style you have to watch for the jump, and some have a flat milled in the shaft so that they also click when they jump.

modelman
12-08-2010, 12:38 PM
Thanks jeff-I have a jump style that I got from my father-in-law. It has a
1/2" shank so it won't fit my mill but I can put it in the drill chuck and play with it but I don't think I can see it any better than the wiggler. I think I will try the lighted one.