[FLUTE HEAD]

When using an edge finder to touch-off the top of a work piece how does it react? I've never used one yet, but do understand the x and y of how it works on a mill. Does it react with an eccentric movement or similar? Thanks Matt

[Rekd]

They're not for touching off the top. If you do, it will damage it and/or the workpiece. Use an indicator or electronic edge-finder for the top.

[Rekd]

...Thanks Matt

BTW, how'd you know I was going to be the one to respond?

[FLUTE HEAD]

Thats my name too. I should have put a comma.

[FLUTE HEAD]

I'll look into the electronic edge finder. Is it used for x and y also? Where can I find an inexpensive one? Any other suggestions?

[Al_The_Man]

Are you talking manual mill or CNC 3 axis probe? The majority of 3 axis CNC measuring probes use a precise 3 axis probe (x,y,z) that breaks an internal optical beam (opto-isolator). and they are connected to a CNC dedicated input called skip input which in turn is programmed by a G31. Essentially what happens is an axis move is programmed with a G31 and when the probe trips, that move/line of code is immediately terminated and the position is captured, the code drops through to the next line.
The measuring routine is in the form of a macro unique to whatever you want to achieve by measuring. The probe has hysterisis that has to be calculated i.e. from the point of mechanical contact to the electronic trip has a certain definite offset which is subtracted from the measured point.
is this what you wanted, or are you sorry you asked
Al

[duluthboat]

This is the easiest way to find the top of your stock with the cutter installed, spindle OFF. Bring the cutter down close to the stock, lay a dowel pin on the stock next to the cutter, and now raise the cutter until the dowel just rolls under the cutter. Now you know the exact height of the cutter. If it is an odd shaped part and you can’t use a dowel, try this very carefully. Take a short slice of paper of known thickness. Turn the spindle on, lightly hold the paper between the part and cutter, and slowly lower the cutter until the paper is pulled from you fingers. These have worked for me for over 30 years.

Gary

[IJ.]

Turn the spindle on, lightly hold the paper between the part and cutter, and slowly lower the cutter until the paper is pulled from you fingers. These have worked for me for over 30 years.

Gary

Very interesting Gary!

Never seen this method so I'll give it a go next time I run the Mill!
(I currently use an electronic but it's 50 mm high so on some projects it can be hard to use)

[FLUTE HEAD]

No, not sorry. I appreciate all the input. Even the simplest subjects we can all learn from. Thats funny, the paper trick has run through my mind. Any more input? Hey maybe a trip laser kit placed above the workpiece at a known distance, when the cutter trips the laser you know you are that distance away. Just talkin outa my head

[Rekd]

Warning about the paper; Don't EVER put your hands or hold anything in your hands next to a moving spindle. If it grabs, your hand could be toast very quickly and very easily. Instead, turn the spindle off and hold the paper, (small piece, 1" square) down flat with a finger and move it back and forth under the tool as you bring it down. You'll feel the paper get tighter under the tool, then it will stop moving. If you want to get close, use the celophane(sp) from a pack of smokes, it's generally about .0003 to .0007" on a pack of Marlboro's

[HomeCNC]

Yes, an electronic edge finder will work for all three axis. However it will only work on metal material. If you are ever going to cut plastic then you will not be able to find the edge using the electronic type.

[IJ.]

Yes, an electronic edge finder will work for all three axis. However it will only work on metal material. If you are ever going to cut plastic then you will not be able to find the edge using the electronic type.

In this case I use the Edge finder on the X/Y corner of the vice then do my setup from there .

Keep it coming guys lots of interesting things coming from this thread!

[723]

on the cnc, I use a regular edge finder for the x&y, and a 1" gage block for the Z. On the manual, I just move the table up untill the bottom of the endmill touches the part. For more accurate work, then I walk over to the cnc and grab the gage block.

[Rob D]

I've used the paper trick, but instead of holding it put a drop of oil on it and stick it to the workpiece. When the cutter grabs it you are within .001.

Rob

[Konrad]

Well,... everyone has it's own little tricks!
Me, for X, Y, I have ground a dowel pin to .200 and holding in collet, apr. 200 rpm. I make it black with a marker, move to the edge, last few thousands by .001 increment's, until the black gets wiped off, move tool up above work piece, then one more move .100 increment to center.

For Z, I use .002 shim stock under the tool.
Konrad

[Klox]

I have seen the process in action as Gary described, it really, really works! Just be carefull not to get the fingers caught by the cutter!

Klox

[singhtechnical]

look for it on alibaba.com