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wmcghee
02-23-2005, 01:39 PM
I have had my shopbot up and running for about a month now and I am very impressed with its capabilities and accuracy. I want to use the probe to set x and y zero with my probe I purchased from shopbot. I was planning on modifying the zzero program to accomplish this. I went in to edit the program but I just can't find the command that does this. The shopbot lingo is very easy to learn and use but this has me stumped. I'm going to use the corner of my spoilboard. I would also like to have a program that I could use to find the center of a hole for setting up jigs, etc. If anyone could give me a few hints on how to do this I would really appreciate it.

Brady Watson
02-23-2005, 04:52 PM
Wayne,
Are you using the Windows software or DOS? There *may* be subtle differences in the file that you would create for each.

-Brady

wmcghee
02-23-2005, 05:39 PM
I'm using windows software. I have the
PRT Alpha96.

Brady Watson
02-23-2005, 06:11 PM
Lemme see if I can do this...

You will obviously need a few vertical blocks to stop the probe when it moves towards the X and Y zero points.

-Brady

Ryan Patterson
02-23-2005, 07:07 PM
Wayne,
To zero the X or Y you will not use the zzero file. Use the file for homing I can't remember the file name. You will need to modify the file switch for normally open or normally closed depending on your probe(oninput 1,1 or oninput 1,0). Then set the offset distance for x and y. If you want X and Y zero to be set at where the probe touches the block the offset distances will be 1/2 the diameter of probe tip.

hope this helps
Ryan

kaaboom_99
02-24-2005, 12:54 AM
Hi Wayne.
Thought I would post for you a set of files I had created a while ago for zeroing all three axis. You would run the z3axis.sbp file which calls the three other files for x, y and z.
I used a 0.250" plate for the z axis and I would lay this across the top of (2) 1" square pieces of stock that I would set up to form a corner. Before running this file you must enter the bit diameter using the VC command.
Look at the z3axis.sbp file and step through it. It should be self explanitory.

Zeroing (3) axis with one switch
Z3AXIS.SBP (http://www.talkshopbot.com/forum/messages/2/Z3AXIS-6537.txt) (1.2 k)

XZERO.SBP (http://www.talkshopbot.com/forum/messages/2/XZERO-6538.txt) (2.6 k)

YZERO.SBP (http://www.talkshopbot.com/forum/messages/2/YZERO-6539.txt) (2.5 k)

ZZERO.SBP (http://www.talkshopbot.com/forum/messages/2/ZZERO-6540.txt) (2.6 k)

cnc_works
02-24-2005, 01:23 AM
I know there is probably a slicker way to do it, but I simply turned my z-zero sideways. Basically edited and substituted X or Y for Z. With a 1/4" bit in and near zero on all three axis, I hold the z-zero plate flush vertically on the corner of the desired axis, X or Y, hit the command (in my case C5 for X and C6 for Y), the bit approaches the plate, touches, retracts, approaches at a slower speed, contacts and sets zero, then retracts a little and goes back to -1/8" (half the 1/4" bit) at that time it sets zero a final time. Repeat for Y. Takes little more time than z-zero. And, actually, if you wanted to do the last movement manually, you could set zero with any unsharpened dimensional bit by doing the mathematics for the final movement and zero set.

I'm thinking of getting a piece of aluminum angle so I can combine the X and Y zero files into one; and I think I could continue to use the aluminum angle for the z-zero.

Donn

cnc_works
02-24-2005, 01:25 AM
Of course there is a slicker way to do it. I'm typing and posting my response, go back and look and there's Perry. Pretty slick.

Donn

propellers
02-24-2005, 11:24 AM
Wayne,I use jigs daily and have a means of zeroing all axis.

I'm not sure exactly what you are trying to do but but be aware the probe will not always be vertical to the table. There are adjustment screws in the probe for contact sensitivity that will keep it from returning to exact center. So as you probe the probe stylus will rotate or turn the chuck of the router and not give you a consistant copy. We put a rubber band on the probe and anchor it anywhere it will attach to on the machine to keep the probe stylus from turning.

I use the homing comand for the xy axis zeroing and the C2 command for the Z axis. These can be added to your program so it will be automatic with each run of the cutting or probing program.

On our jigs we have a reference for 0,0,0. With a reference at each end of the jig we can install anywhere on the table accurately. We then run the xy to the prox switches to learn the distance to the prox. sw. From this we will have a reference to the jig at all times. The homing command is ran andwhich will zero xy. The cutter is then ran back to the jig and we will C2 which will zero X.

This all provides a reference and a starting point for a the program. I find that when running a program over and over the zero will alter due to agressive cutting or quitches and occational program lockups. But once this information is known and logged it is very easy to just run the homing command and you will be exactly on the rference point without a lot of frustrtation.

I have included this into the program so when the cut if finished the program will automatically run the homing and C2 command rezero all axis and park until I load a new part and press enter.

I no longer have parts cut incorrectly sine the machine will always check and set the same location every time.

Hope this presents a few ideas for you. What are you planning to produce on your machine?

dirk
02-24-2005, 04:36 PM
Lonnie:
Your last post stated:
"On our jigs we have a reference for 0,0,0. With a reference at each end of the jig we can install anywhere on the table accurately."

How are you referencing the Jig? Are you Measuring by hand or touching off with router?

srwtlc
02-25-2005, 09:54 AM
Why risk inadvertent damage to your probe. I use a corner zeroing block that is just a aluminum angle screwed to the corner of a block of wood.

2415
X & Y zeroing file

2414 (2.9 k)

I can index/zero off the corner of a jig, material, or table by positioning a broken off 1/4" bit or the actual cutter I'm going to use near the angle and run my modified zzero file. The file will ask for and take into account the diameter of the bit. Sometimes I screw a secondary block under it to zero to the inside of a plywood square screwed down to the table for parts positioning. Note that the block is offset to provide a lip for positioning and a stud is provided for hooking the input wire to. With this method, I have never bothered to purchase prox switches.

fleinbach
02-25-2005, 11:07 AM
Scott

Great solution.

I have had a hard time trying to figure out why anyone would want to use the prob for zeroing. It creates 2 extra steps everytime you need to re-zero. You have to remove the bit, then insert the prob and then remove the prob to reincert the bit.

Your solution allows you to keep the bit in the tool and just re-zero. And I like the safty factor of the bit not hiting sideways on some fixed object.

propellers
02-25-2005, 11:29 AM
Dirk, The jig is a sheet of ply. At each end of the ply we have a 1/2" hole used for alignment when the pattern is placed on the table.

Most of our cutting is with a 1/2" cutter.
Using a 1/2" drill blank chucked in the router we align one hole in the jig..screw that end of the jig to the table. Next we run the router to the other end of the pattern and align the other hole and screw that end of the pattern to the table.

We use the first hole as the 0,0. I then move XY to the prox sw. to have a reference to 0,0, we log these values minus .5" to be used when the machine error or a program locks up we can use these values again to return to the exact 0,0 since we know were 0,0 is from the prox sw.

At the start of the cut file I also insert these values. When the file completes it will home XY, move off the prox sw. -.5" reset to zero and park. This allows an uncut part to be placed in the jig. When the new part is ready to be cut I will use enter to continue the program...now...with the earlier values of the known distance to the prox sw. placed in the file the XY will move to that position which is really my original 0,0.

With the router setting at the original 0,0 I then have in the file Z2 which will now zero XY. So XY has the 0,0 position it originally was located and I know even if the stepper skipped the machine is ready at the correct position every time I start a new file run.

The next line moves the machine to a spot I want set my Z0, I put a pause in the file to provide time to place the metal zeroing foot under the cutter, hit enter and the Z axis is zeroed, another pause allows removal of the zero plate.

I hit enter again which moves the cutter to the cut area and then SO will start the router and money making parts are produced.

I had thought of putting a permanent zero plate on the machine so I can command the XY to locate there, C2 command will zero then move the Z axis to a determined height that represents my zero position then add a line for the ZZ command in the program so when I load the part I run the file and never have to babysit the SB until the SO 1,0 command shuts off the router and parks the machine clear for a new load of the part.

Hope this presents some food for thought, call 419-877-5557 daytime or write if you have further questions.

wmcghee
03-03-2005, 12:48 PM
Thanks for all of the input and ideas. I used the programs that Perry has and modified them to work the way I had planned. I will set 0 at the lower left corner of my spoilboard with the probe.

What Lonnie said though about the probe not always exactly centered does raise some concerns. I didn't realize this. But I do like the way he sets his fixtures up with the holes and drill blank and rezeros before each run. If anyone has a good source for proximity switches at a reasonable price please let me know.


I would also have to agree with Scott about causing damage to the probe. I will need to be very careful and try to avoid this as it could very easily happen. I also put the
"ON IMP(1,0)" before any moves to try to avoid damage.
Although it is extra steps I don't see it as that much trouble since setting x&y zero should not have to be set that often unless the machine losses its position. Although proximity switches is the way to go for speed and ease.

Lonnie asked what I plan on doing with the machine. I don't have a real clear answer to that. I have built custom cabinets for a couple years now. I guess you would call it a hobby even though I have charged for most of my work. I would also like to build some furniture and outdoor stuff. I also have a 16 year old boy that I don't think will go to college. I would like to teach him about the machine and maybe get him started doing some stuff. He just has no interest in it right now
set-y.sbt

2416 (2.1 k)