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View Full Version : Laser "crosshairs" for locating reference x,y position


Gerald D
Fri 25 January 2008, 21:17
Copied from another thread . . . .

. . . . Most interesting off-center tool is a down pointing laser dot - position the dot on a reference point, run mini-program and router bit moves reference position.......

Greolt
Sat 26 January 2008, 02:39
Or a cross laser. Can be had on ebay for less than $5

Have a look at this thread. Not a MM but the principal is just the same

http://www.cnczone.com/forums/showthread.php?t=48752

For this sort of cost the accuracy won't suit NASA but for a MM it's great.

And quick! A real time saver.

Disregard the zero device and shuttle pro, just look at the laser cross. :)

Greg

J.R. Hatcher
Sat 26 January 2008, 05:06
Greg, now that was :cool::cool::cool::cool: (cool). Guys if that video and all of that technology didn't make you p in your pants .......then you just didn't need to go to the bathroom in the first place :eek:

Greg said "Disregard the zero device and shuttle pro, just look at the laser cross. :)" I say nooooo breathe it all in.

Greg J
Sat 26 January 2008, 15:38
Greg,

That video was great!!!!

Everything in it has significants to MM's.

Great motivation for getting mine done. Back to the shop.

cncb
Tue 29 January 2008, 20:17
That video is great, the aussies are very creative. It's very basic, and fundamental what was shown. It's nothing new, but it is the fact that he took those three steps, z zero - xy ref and jogging with a cheaper but easily available pendant and showed that you can get the same functions of higher end machines on the diy side. When I first saw it I watched it 2 more times, sent chills down my back, reminded me why I got into diy cnc in the first place :).

Greolt
Wed 30 January 2008, 21:41
It might be just worth mentioning here to avoid any confusion.

The three different things shown in the video (Auto Tool Zero, Shuttle Pendant and Laser Cross) are not in any way interdependent.

Any one of these three can be implemented on their own. They are quite separate.

Greg

Gerald D
Wed 30 January 2008, 21:49
Greg, can we pay you a retainer to hang around here and teach us these things? :)

What rev of Mach3 are you using?

Marc Shlaes
Wed 30 January 2008, 21:58
Amen! I second that!

Greolt
Thu 31 January 2008, 04:58
Wow I've got you blokes bluffed haven't I. :) I'm just a simple carpenter.

Been a long time lurker on this site. No room in my shed for a MM. :(

I hang back a bit these days with Mach versions. Been caught with too many problems using the latest all the time.

Greg

smreish
Thu 31 January 2008, 06:15
Okay - I was so impressed by the video I just ordered a shuttle pro pendant!
Sean.

Greg J
Thu 31 January 2008, 06:38
Greg,

I've already received my pendent (on J.R.'s recommendation), but, once my MM is running, I'll be adding the "laser" and Z zero device.

As for the vacuum hold down, I agree with Gerald, that its a power hog device. But a small vacuum "board" could be nice for the smaller, custom, work. Maybe take a side stream from that 5 hp (talk about overkill) dust control system I'm installing .... hmmmm ....

Doug_Ford
Thu 31 January 2008, 10:25
Greg (from down under),

Thanks a million for taking the time to share this info with us. I'm definitely going to add it to my machine.

J.R. Hatcher
Sat 15 March 2008, 17:59
Greg, Sorry about getting sidetracked on the zero plate, I'll get 1 set up ASAP.
I've been messing around a little with the cross hair laser and found a fast way to mount it, tell me what you think. It's a cord grip and it allows for easy alignment . http://www.factorymation.com/s.nl/it.A/id.5486/.f?category=14659

J.R. Hatcher
Fri 24 October 2008, 04:54
Nils how would the laser work with the dust foot in place?? I mounted mine to the underside of the Y car. The laser I bought has focus capability. It runs off a battery that I will need to change ever year or two.

sailfl
Fri 24 October 2008, 05:46
JR

That is a good point. I have not started to use mine so I have not added a dust foot. I would have discovered the problem then.

domino11
Sat 08 November 2008, 20:57
The laser can be way out from where the true center of the bit is. The only thing it needs is to have the same position every time. This is not a problem since it will be hard mounted. You just put in the "offset" from where your laser is to the center of the bit in Mach. This way you can mount your laser so it clears the dust foot entirely.

J.R. Hatcher
Sun 09 November 2008, 04:09
Heath please be more specific. Exactly where and how do you enter the offsets in mach, and how do you use them. I have had my laser mounted for months now but can't seem to find the time to get it setup to use. Thanks for the help.

domino11
Sun 09 November 2008, 18:04
Sorry JR, I have not done this myself yet, but from the videos I have seen on the zone, most guys have the laser offset from the router center and they have the offset programmed in to Mach so when they say Zero, then Mach just moves the router so the bit is now over where the laser dot or cross was and sets the true zero then. I think Greg (Greolt) has a little more on this in his thread on CNCzone, check higher up in this thread.

Greolt
Mon 10 November 2008, 01:26
relevantre
...........Exactly where and how do you enter the offsets in mach, and how do you use them.


You will need to make a button on screen. Call it "Laser Zero" or whatever makes sense to you. And set it for "VB script function edited in Mach"

Then in Mach, place this code in the button script,

Code "G91 G0 X -50 Y -50"
While IsMoving ()
Wend
Code "G90"
DoOEMButton (1008)
DoOEMButton (1009)

Edit the numbers shown in red for the relevant laser offset.

Greg

Greg J
Mon 10 November 2008, 06:00
J.R.,

In Mach, on the main screen (I have got to get a screen shot program) there is an "offset" section. Click on save offsets (lower right, yellow button, I think). Pick a G command and enter the X, Y, and Z offsets.

I have G55 set for my offset. Normally, what I do, is "Refall" first, then bring up the G55 offset.

There are numerous ways of setting the offset. Add "G55" in the G code, or manually enter "G55" in the command line, etc. etc.