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djarboe
12-29-2010, 01:37 PM
I've run into this several times, and suddenly solve it. problem is, I don't remember how.
I have a piece of cherry about 11 inches long. Since this is only slightly longer than my carving, I attached a rail on each side, also cherry, that is much longer. At each end of the rails, I put a piece of masking tape across them. I also put masking tape along the bottom of one rail, just to make sure the tracking roller is, well, tracking.

So, when I start the project, I tell the machine not to keep it under the roller, since my rails are so much longer than my project. The machine then measures the width, and then starts moving the board to the front of the machine. It finds the masking tape, registers on the back edge and starts pulling the board back in to locate the front edge. It stops about 2 inches into the actual board, and thinks it is done measuring.

By the way, the rails are 31" long... plenty for an 11" carving, and when I tell the machine to measure the board, it get's that right.

What am I missing here?

Ike
12-29-2010, 02:24 PM
Is there a gap between the actual board and the rails? The sensor will see the break as the end of the board. My next question why add the rails if you are not using the rollers? I make signs and never use the rollers I use the exact size of the board from the designer to the machine and never have any issues. Be advised it is not recommended not using the rollers and to used the 7" rule.

For example your project being 11" long, I have a silly question I run into with my sign business when you say 11" it is the length not the width? People call the length the width, anyway I am sure you mean length by the way how wide is your board?

Back to the 7" rule if your project is 11" your board needs to be 18" or a sled that has 3.5" on each end. I find it a waste to use a longer board, but that is me! Why not try just loading the board or a test piece since it is Cherry and run the project the 11" long and whatever the width is! Cherry is dark and will mess with the sensor so you may need duct tape or contact paper on the top surface. A white contact paper would be best for the edges use some sandpaper to cut it to the edge rather then trying to make it exact. Just lightly cut the paper against the edge with the sandpaper 100 grit or less should work!

Ike

cnsranch
12-29-2010, 02:35 PM
Thinking out loud.....

I've been told that the machine starts looking for the end of the board once the board comes out from under the front roller (the one to the left as you're facing the key pad side). If it's stopping way short of that, could there be a roller issue (stuck, maybe?)

If the rail isn't making constant contact with the brass roller, there could be an issue, there, too. Look at the underside of that rail, and make sure there are marks all along the tape - it will get compressed by the brass roller, and make tracks, evenly spaced, all along the tape.

djarboe
12-29-2010, 03:29 PM
Good questions. I use rails to "fool" the machine into thinking the board is bigger than is actually is, in both length and width. That way I can save wood, work with smaller pieces, and not have 7" of scrap on each carving. I'm just cheap.

By Length, I mean the board length setting in the program, since the CarveWright designs sideways (to me anyway). In use, the carving will be hung at 90 degrees to the machine software. In that case, the 11" would actually be the height. I'm used to doing solid modeling with SolidWorks, and have to reset my brain (tiny as it is) coordinates every time I use the CW software.

eelamb
12-29-2010, 04:01 PM
I use rails all the time, so I have a few suggestion. Make sure the ends are taped (tight but not so tight as to pull the rails inwards), the rails are very close to the same thickness of the boards, the tape is at least 1.5" wide (3/4" is necesary but a 1.5" tape width avoids measurement problems), the tape is tan or white (not blue) and last but not least the actual board is flat and square. The only problems I have had is when the baord is not flat or not the same thickness thoughout. As to the rollers I have tried it both ways and not had any problems, so I normally say stay under rollers, since I have plenty of length to work with, such as in your case. Hope this helps!

djarboe
12-29-2010, 04:06 PM
Found the solution! Went searching the forum questions and found how to make this work. Found a thread that said you have to set the "board size" to the size of the rails (length/width) and then pick "don't stay under rollers". That worked.

I am getting old, but I don't remember having to do that in earlier software/firmware versions. Is this a new enhancement? (Please note, I may also have forgotten this.)

Anyway, it works.

djarboe
12-29-2010, 04:13 PM
I have always done exactly the same thing, and use 2" wide regular masking tape, which I merely lay across the rails, but never pull them (learned that lesson the hard way.) All my wood is jointed flat on one side, and then run through my planer to micrometer accurate thicknesses.

I made dedicated custom rails for the two board thickness I use. They are within 0.005" of the same thickness as the boards.
I found a solution in searching through the forum messages. See my solution post.

Problem is that so much time goes by between my opportunities to play that I forget the tricks. Part of getting old, I guess.

Dave

eelamb
12-29-2010, 04:19 PM
Thanks for the post of your solution. I hav enot used the rails with the new version, and will have to remember this trick.

fwharris
12-29-2010, 04:37 PM
This is how I do my rail set up for small pieces.. picture is just a quick rough draw not to scale or aligned..

The carving board is centered length wise between the rails. Tape the 2 rail ends and a center tape on the center of the board to the end tape. The tape is for filling in any voids so that when it is being measured the optical sensor does not see any voids in the board. If it does you will get either an error or incorrect measurement.

Since the total size is bigger than the project size I select NO for staying under the rollers and to center on the board...

I have not tried this with the newest version but I do not see why things would have changed.

djarboe
12-29-2010, 04:59 PM
I actually tried the tape strip down the center, thinking the difference in cherry/making tape colors might be the problem, but seriously never had to do that before. However, that did not work either. Since upgrading to the latest version, and reading some related posts, I found that we now need to set the board size to the total rail size. That works. Then just make sure you choose the option to center the pattern on the "big virtual board".... without the center stripe. I still pick "NO" for staying under the rollers.

fwharris
12-29-2010, 05:07 PM
off to the shop to test....

Back from my test and all went as planned. It went thought all of the normal steps as before and went to asking for the bit...

I just went back and read the original question on this post and I think I know what your issue is..

It measures your width then does the length. After if finds the first end and starts the other direction and then PAUSES and ASKS "keep original size?" and displays 2 numbers. The first number is your actual board and rail width, the second number is your design width. If you continue "press enter" to the "keep original size" it will carve as you have it set up..


Let me know if this was what

djarboe
12-31-2010, 09:51 AM
off to the shop to test....

Back from my test and all went as planned. It went thought all of the normal steps as before and went to asking for the bit...

I just went back and read the original question on this post and I think I know what your issue is..

It measures your width then does the length. After if finds the first end and starts the other direction and then PAUSES and ASKS "keep original size?" and displays 2 numbers. The first number is your actual board and rail width, the second number is your design width. If you continue "press enter" to the "keep original size" it will carve as you have it set up..


Let me know if this was what

Will try that on my next carving today.