Using an Edge Finder - Tormach CNC

Tormach on the web @ http://www.tormach.com

Overview:
This video reviews how to use an edge finder and the difference between a mechanical edge finder and an electronic edge finder.

Material: 2" Aluminum
Cutters: Mechanical Edge Finder, Electronic Edge Finder
Speed: variable
Feed: n/a
Machine: Tormach PCNC 1100

Background:
Essentially an edge finder is a dynamic indicator of the location of a work-piece edge with reference to the center line of the spindle to which it is attached.

Fixtures & Tooling:
The mechanical edge finder in a simple device and can be purchased for as little as $10 USD. In order to operate this type of edge finder, you need to have a rotating spindle.

An electronic edge finder is a bit more complicated and will cost a little more. Its main advantage over the mechanical edge finder is that it can work in a NON-rotating spindle. It is battery operated and works by lightening up its internal LED (usually red) when the electrical circuit formed by the instrument and the machine is closed.

Motion Planning:
The edge finder is put in the rotating chuck of the milling machine and the work-piece is moved towards the edge finder.

When the work-piece and the edge finder come into contact, the rotating motion of the edge finder visibly changes.

In use, the spinning edge finder is moved into contact with the edge that you wish to locate. As the lower cylinder of the edge finder touches the edge, that lower cylinder "kicks" to the left (assuming a clockwise rotation as seen from above). When the kick is observed, the axis of the spindle and the edge of the work-piece are located 1/2 the diameter of the edge finder from each other. This is typically 0.100" but it can be different, so make sure to check.

Cutting Process & Results:
With either a mechanical or electronic edge finder, you will be able to center your work-piece accurately every
time.

Key Words:
edge finder, mechanical edge finder, electronic edge finder, wiggler, centering, machining, milling techniques, CNC, Tormach

Category:

Science & Technology

Tags:

• Tormach
• CNC
• edge
• finder
• mechanical
• electronic
• wiggler
• centering
• machining
• milling
• techniques

[tomclemans]

Excellent video - good explanation and demonstration. Thanks - I will show this to my students today.

However, I learned the hard way (by destroying the edgefinder and damaging the part) to turn off the spindle before raising the Z axis when the edgefinder is touching the part.

[TheHireTheBetter]

Thank you SO much for posting this. I've watched several "how to use an edge finder" videos on YT and all of them have the same problem: they either use terrible cameras, or they don't zoom in enough - you can't see anything! Again, thanks for posting a video where you can actually see the edge finder in action.

[whereisdave]

@Quinsanta try cnczone forum its brlliant

[Quinsanta]

Thank you very much for posting this. As a hobby machinist, I don't have access to machinists to ask these type of simple questions.

Best Regards,

Jon

[crazybritishlad]

i can run our one at 1600 rpm all day long

[FactoryDragon87]

@VirtRampage With this tool You may forget 0,005mm accuracy, but 0,0005inch= 0,012mm maybe it is posible. Exist too many reasons why You never get 0,005mm accuracy useing touch methods. Better is use dial gauge tool! Also useing dial gauge tool You may find out that- workpiece is perfect paralel to work axel- X, Y or Z.

[MarekUmbug]

You will use probe .

[riltjd]

@fortmcmurraycash so how would you make a circle? just pure skill? hehe...

[fortmcmurraycash]

spring loaded edgefinder is only good for about a half anyways. they will differ...they get fucked up quick too. im a manual guy tho no CNC, my best is with a rollin paper...zig zag whites are my edgefinder LOL. i run mine usually about 1200 rpm...never any higher.

my "Z" axis is my left hand and "X" is my right hand ;-D

[VirtRampage]

its usualy 0.005mm accuracy