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View Full Version : Registration for flip side work trouble - Mary Mother o' God....



johnm
06-11-2006, 11:29 PM
Folks -

I think 'bots have the same "crisis detector" found in so many other machines with electronics (read: copiers) When we're screwing around, or working on an element that isn't "mission critical" everything is fine - loose power in the middle of a cut? No problem, XYZ position is mantained.... Got something that HAS to be right... pffft...... 0,0 is somewhere around Barstow, on the edge of the desert... with apologies to Hunter S. Thompson

Okay, we were cutting picture frames with a 1/4 EM for doing all of the cut outs and rabbets, and a V bit for decorative carving. When we lost our registration, we went back and looked at the location of one of our registration dowel holes, and then plotted a reciprocal course back to what we assumed was 0,0. It looked okay, but we were off by 1/4 or so on our X. Y looked okay, but WTF? I had placed the EM directly above the dowel hole and VERY carefully lowered and positioned it so that I was probably within .010. When AC/PW gives you the location of a hole, is it taken at the edge or at the center?

We wasted several hours and 3 frame blanks, and Rose is spooked.... The last time this happened, we used the line of code to plot our way "home" but we picked the "highlighted" line, instead of the one before it. So, same problem, different solution, and we still have the same problem.

Aside from whatever gremlins are making 0,0 become a work of fiction, how the heck do you recover from position loss so that you can resume your location and registration point. We're only working in MDF, so it's not about $$ (this time) but boy....

On the theme of fiction, and writing, I can tell you that I learned some new words..... I am hoping someone can shine some light here...

Thanks in advance...

John & Rose

mikejohn
06-11-2006, 11:56 PM
John
There is another possibility if you can recognise a position on your workpiece.
Assume you had a z move down that you can recognise.
If you air cut to this point you can find the line number (easier if its after a J2 or J3 line)
Now, align your bit with this point x and y (I am assuming z is OK, if not re-set z with the z plate)
Once you are happy with the bit position, set this new x,y position with VA (which you can read from the line number in the file).
Now the bot is where it is supposed to be.
Restart cutting with FG at a suitable line.
Incidently, I can not see a connection between your question and the thread title

.............Mike

johnm
06-12-2006, 12:38 AM
Mike -

Forgive me.... The registration issue is one of wanting to flip a panel over to do V carving on the other side, and have it registered with the end mill through cuts - think of a v bit carving around the opening in the middle of a frame... when we've done the rabbet clearance in the back, and all of the through cuts, with bridges... flip it over so we can carve the face of the frame...

HTH...

John

mikejohn
06-12-2006, 12:51 AM
John
I'm sorry, I don't fully understand.
Are you also having a problem registering after flipping?

..........Mike

paco
06-12-2006, 10:22 AM
John,

once you got you design, position it where you need it in your material.

Next, draw one vertical line one horizontal. Center 'em both FROM you design (not from the material).

Next draw ONE of your registration hole (for dowel); say the lower left one.

Mirror it using the line(s) (generaly selecting the hole/circle first then the "mirroring" line) until you have four around.
You're ready to work on your flipping process.

You'll use one diagonal pair of hole for the registration in the material and the other diagonal pair into the spoilboard.


3929

This is one way to do this, it's basic so it'll get you into an easy start for two sides machining. The accuracy is all about the dowell and hole; must be best match for tightness. Try to avoid spoilboard screw with the spoilboard holes...

beacon14
06-14-2006, 09:47 PM
John, for your application there is no need to rout both sides of the workpiece in the exact same location on the SB.

I would do this by cutting the backs out wherever I wanted to, incorporating a 4 hole pattern as Paco so conveniently drew above. Then I would use the SB to drill four holes with the same spacing into a jig or scrap piece of sheet material elsewhere on the machine. Insert dowels into each hole in the jig, leaving them proud by just less then the depth of the holes in the workpiece backs.

Then you can alternate between routing fronts and backs while you change out the one just completed. The machine no longer has to wait for you to turn the blank over.

Even if you are only doing one or two this method is quick and simple.