Guy, actually using a collet or a chuck of whatever with or without (much) run-out mostly doesn't matter when using a rotating edge finder. It will run true to the rotational center of the spindle. So, if you want to find the center of your work piece (splitting the difference between two measurements), this will work perfectly. However, not rotating the digital edge finder results in a measurement error in this case (finding the center) if the edge finder is not exactly in the center line due to (minor) deviations of the chuck, collet, etc. A mechanical edge finder will show a sudden shift opposite to the rotation when the friction between the work-piece edge and the finder is higher than the friction between the finder point and its base. That is a tiny force, so the finder just touches the edge. If used in this way I am sure the mechanical finder is superior to this not rotating 'digital' solution when it comes to finding the exact center between two measurements,
I understand and agree, but I measured the run out of the Fowler unit at .0003" in my R8 collet, so non-rotating measurements are as accurate as I need them to be on my machine.
I like both versions of edge finders that you showed. I just prefer the Starrett brand myself. I have yet to try the light switch version, may have a look into that. I have used a diy electric contact edge finder on my home built CNC machine, no lights but it sends the 0.00 position signal to the controller and it will automatically check all 3 axis in both - and + locations.
@@GuyMarsdenMakesStuff if I ever convert my mini mill to CNC I will most definitely use the device that I made for my CNC router because it is extremely accurate
I have been meaning to get one of those , Not sure if I should get the beeping one with the LED or this one you show ? I have an old spring loaded one that works but I like the tech of that style..
@shawnmrfixitlee6478 The led style is less accurate than you might think. Any runout of the collet plays a part in the equation with these and they are generally considered sub par. Suburban tool has a good YT video outlining the differences.
I don't bother with edge finders. I chuck a short precision ground rod and hook one end of my multimeter's alligator clip to it. I hook the other lead to the part and set the multimeter to continuity mode. I slowly creep the table until the multimeter beeps, meaning the rod contacts the part completing a circuit.
I don't understand how you are electrically isolating the part. A continuity meter would measure a connection before you touch the two parts because the whole Mill and vise etc are connected.
Guy, actually using a collet or a chuck of whatever with or without (much) run-out mostly doesn't matter when using a rotating edge finder. It will run true to the rotational center of the spindle. So, if you want to find the center of your work piece (splitting the difference between two measurements), this will work perfectly.
However, not rotating the digital edge finder results in a measurement error in this case (finding the center) if the edge finder is not exactly in the center line due to (minor) deviations of the chuck, collet, etc.
A mechanical edge finder will show a sudden shift opposite to the rotation when the friction between the work-piece edge and the finder is higher than the friction between the finder point and its base. That is a tiny force, so the finder just touches the edge. If used in this way I am sure the mechanical finder is superior to this not rotating 'digital' solution when it comes to finding the exact center between two measurements,
I understand and agree, but I measured the run out of the Fowler unit at .0003" in my R8 collet, so non-rotating measurements are as accurate as I need them to be on my machine.
@Michel-Uphoff This! You are indicating the center of the spindle, runout of a collet or chuck does not matter.
I like both versions of edge finders that you showed. I just prefer the Starrett brand myself. I have yet to try the light switch version, may have a look into that. I have used a diy electric contact edge finder on my home built CNC machine, no lights but it sends the 0.00 position signal to the controller and it will automatically check all 3 axis in both - and + locations.
I think I may alternate between these two depending on the application...
@@GuyMarsdenMakesStuff if I ever convert my mini mill to CNC I will most definitely use the device that I made for my CNC router because it is extremely accurate
@@taranson3057 I measured the run out of the Fowler unit at .0002". I call that pretty good accuracy!
@@GuyMarsdenMakesStuff I would hope so :-)
I have been meaning to get one of those , Not sure if I should get the beeping one with the LED or this one you show ? I have an old spring loaded one that works but I like the tech of that style..
I considered one with a beep, but one of the reviews said that it was a really annoying sound.
@@GuyMarsdenMakesStuff ah yes , I could see that being an issue while trying to concentrate on the job at hand ..
@shawnmrfixitlee6478 The led style is less accurate than you might think. Any runout of the collet plays a part in the equation with these and they are generally considered sub par. Suburban tool has a good YT video outlining the differences.
But whats the repeatability ? Isn't that the most important thing to understand here ?
Absolutely. I think it's more about personal style though. I like blinky lights more than I do wiggly bits.
Yes.
I don't bother with edge finders. I chuck a short precision ground rod and hook one end of my multimeter's alligator clip to it. I hook the other lead to the part and set the multimeter to continuity mode. I slowly creep the table until the multimeter beeps, meaning the rod contacts the part completing a circuit.
I don't understand how you are electrically isolating the part. A continuity meter would measure a connection before you touch the two parts because the whole Mill and vise etc are connected.