Edge Finder

[slamman]

Can an edge finder normally used on a mill be used to find the edge of material on a CNC router?

If so at what RPM. I have seen it written that edge finders should be used at 1000 RPM, but my spindle isn't supposed to operate below 9,000 RPM.

[christinandavid]

How precise do you need to be? Accuracy with edge finders varies depending on the type of edge finder (mechanical/electronic) and the method employed (run-off/light line).

Or are you refering to the conductive electronic variety (meaning you must be working with metals) which can be out if the surface isn't scrupulously clean.

If you can live with .1mm error just use a dowel in the chuck and a piece of shim to set with.

For supreme accuracy I always use a DTI.

DP

[dertsap]

my spindle isn't supposed to operate below 9,000 RPM.

too dangerous

I accidentally spun and edge finder at about 8000 rpm and the tip flew off like a bullet
i agree with the use of a dowel pin

[slamman]

Understood. The shop had a couple of mechanical edge finders for our mill and I was unsure if they would be useful for the cnc. Had a problem with a powerloss between a rough cut and the finish process and lost zero...consequently the finish pass ended up being just a tad off...like a 1/16th or 1/8th its hard to tell. I was hoping the edge finders would solve such a problem. I am just beginning to work with the cnc router. My thought was I need to line the X and Y edges up on the center of the bit which is very hard to do. Is there a better way? What is the dowel method?

Thanks

[dertsap]

What is the dowel method?

Thanks

put a round dowel pin or equivalent into the spindle , jog the pin toward the workpiece and slide a piece of paper in between while jogging , once the paper is tight between the two then set the workshift and add 1/2 the dia of your pin

[TarHeelTom]

I haven't used one, and don't see much written about them, but there are also laser edge finders.

Total lack of experience here.

But, they don't need or want the spindle turning at all. Seems like 0 rpm should be an easily attainable speed for your spindle.

Anyone here used a laser edge finder?

Tom

[dertsap]

there are a number of guys using the laser edge finders or making their own , ive got a cross hair laser kicking around here somewhere , i find the accuracy to be questionable but probably good enough for some wood working