locate midpoint...

[junior33]

Contoler reads: GE Fanuc series 18i mb5

If I edge find from one end of a 20 inch long piece and then edge find the other in order to find center, is there a short cut persay that does a midpoint location?????anyone...

[DareBee]

If your part is 20inches, all you need to do is edgefind 1 end and offset 10inches + .5*dia of edgefinder.

But that is not what you asked.
I don't know that control or whether it has a center function.

Zero the control at the 1st end, find the second end, then G91 back half of the number on your axis display (or G90 to half of the number on your axis display).

[ckirchen]

Here's what I do whenever I want to find a midpoint:

1. touch off on the left side and record the DRO reading
2. touch off on the right side and record the DRO reading
3. add the left DRO reading to the right DRO reading and divide by two
4. jog to the result; that's your midpoint

If you use an edge finder, you don't have to take into account its diameter, as long as the edge finder is concentric with the spindle.

Hope that helps.

Chris Kirchen

[junior33]

Originally Posted by ckirchen Here's what I do whenever I want to find a midpoint: 1. touch off on the left side and record the DRO reading 2. touch off on the right side and record the DRO reading 3. add the left DRO reading to the right DRO reading and divide by two 4. jog to the result; that's your midpoint If you use an edge finder, you don't have to take into account its diameter, as long as the edge finder is concentric with the spindle. Hope that helps. Chris Kirchen

i realize this.....I do all that...I am just checkin to see if there is any short cuts...automatic type.....

[junior33]

Originally Posted by DareBee If your part is 20inches, all you need to do is edgefind 1 end and offset 10inches + .5*dia of edgefinder. But that is not what you asked. I don't know that control or whether it has a center function. Zero the control at the 1st end, find the second end, then G91 back half of the number on your axis display (or G90 to half of the number on your axis display).

how does the line read to use the G91????G90???MDI mode????thank you by the way.

[ckirchen]

Originally Posted by junior33 i realize this.....I do all that...I am just checkin to see if there is any short cuts...automatic type.....

not without an integrated probing system; either off-the-shelf (such as renishaw) or homegrown (http://www.industrialhobbies.com/how...ouch_probe.htm). you'll also need macro capabilities to do the math.

Originally Posted by junior33 how does the line read to use the G91????G90???MDI mode????thank you by the way.

if the length is known and you edge find to the left end, the MDI's would be:
- G90 G00 X[current_x+length/2+diameter_of_edge_finder/2]; or
- G91 G00 X[length/2+diameter_of_edge_finder/2].

Chris Kirchen

[machinist_1]

Simple. If you touch off on the left side X, go to your offset page and input X-10.0 input+. Do the same for your Y axis if needed. I use the same control on my FADAL VMC4525.

[machinist_1]

Simple. If you touch off on the left side X, go to your offset page and input X-10.0 input+. Do the same for your Y axis if needed. I use the same control on my FADAL VMC4525. Oh, make sure to add for you edge finder.

[DareBee]

Originally Posted by machinist_1 Simple. If you touch off on the left side X, go to your offset page and input X-10.0 input+. Do the same for your Y axis if needed. I use the same control on my FADAL VMC4525. Oh, make sure to add for you edge finder.

You forgot the edge finder.
So it would be X-(10+(1/2 of edge finder))

In my control I can input edge finder dia for setup so the offset would be a straight X-10.

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