Question about cutting again on already carved board

[arttocad]

Not sure if I have posted here before but I've had my used machine (48hrs of cutting time) for about 5 months now and not too much troubles except yesterday, the flex cable popped out and today I had my second torn belt :mad:. If this should be in a different section of the forum, I apologize in advance.

I was cutting a design that had lots of carving and then several cut through details. It is on a 11 3/16" x 48" x 1" pine stair tread. I squared it up and removed the bull-nose on my table saw and the board was perfectly flat. Most of the carving went off without a hitch but part way through, the flex cable popped out of the z-truck. It looks like the ball groove is showing signs of wear. Is there any way to turn that part of the shaft? Only the area at the ball is getting worn out and the rest of the groove is in perfect shape. I re-inserted the shaft after cleaning and lubing it. Didn't pop out again after another 2 hours of carving.

Then I switched over to the 1/8" cutting bit and most of the cutouts were fine. It got to one where the tabs were insufficient to hold part of it in place, the cutout dropped between the belts, and the rear belt was history. So, I already had over 5 hours into cutting and didn't want to have it go to waste almost at the end. I made a reference stop to mark where the board was and then removed the board to replace the belt. Swapped out the belt and cleaned a bunch of sawdust out while I was at it. Then went about carefully placing the board back into the machine. The board tracking roller probably moved at some point but I was hoping it wouldn't count that since the machine had been stopped.

I started cutting again. It went to the first cutout and started fine but then as it approached a corner, it was misaligned by about 1/4" in the x-axis. I stopped the machine, lifted the board off the board sensor, and moved it about 1/4". Started again and it was still misaligned. Frustration was building at an immense rate by then. Then I had the "genius" idea of modifying the program to remove all of the cutting that had been completed and just have it finish the last few cut-outs and the perimeters. Since most of the surface had been carved away, now I can't get it to go all the way through the calibration on the new program. Here is what has been done so far:

-Tried manual measure of board: width works fine, length fails every time, haven't tried height.
-Tried to start my modified program: again fails on length measurement.
-Tried laying a strip of masking tape down the length of the board under where the optical sensor was lined up: length measurement worked once out of five attempts, then the machine went crazy when moving on to the bit calibration (by crazy I mean jogging rapidly in alternating directions on both x and y axis). I tried stopping and restarting the machine several times but it kept doing the same thing.

Is there a way to manually key in the board dimensions? If not, is there a way to override where it is trying to take the length measurement? There are about 3/4" wide strips down the full length on both sides of the board. Is there a way to manually assign where to do the board height/bit calibration?

My last idea I have to fix my dilemma is to try and flip the program and the board over but that seems risky. If I can't get a solution on the machine, I will have to resort to cutting the rest by hand or scrapping the project. Neither are appealing options. If anyone has some insight or ideas on how to get a mostly carved board to re-calibrate, I am all ears.

One more thing my machine has been doing: The bit calibration plate does not pop out by itself anymore. I have been opening the cover and manually moving it into place. This seems to work OK but is this a common problem and is there a solution for it?

I appreciate any and all responses. I may not be able to check back in on the forum until mid-week or next weekend and hopefully there is a solution waiting here for me.

[Sallen1215]

Can you post the MPC file so we can see the design your talking about? also it seems you may have some cleaning issues as to why the bit plate wont come out. As for the skipping back and forth, check to make sure you have full contact with the brass roller on the keyboard side of the machine and that the rubber "o" ring is in place. Depending on how mechanically inclined you are there are several places that need to be lubricated and gears that should be looked at to make sure the alignment issue isn't a warning sign to bigger issues. I have lost several carves halfway through and usually what i do is always use my board placement on center (as long as the board is not cut the project should stay in the same place) and i either let the machine go through and after it makes a start on the carve i remove the bit and let it "air carve" until it gets close to the point at which it stopped. You shouldnt have any problems with that method except if you have board alignment issues that can be caused by gears slipping or missing teeth as i would suspect if a piece of the project jammed the machine and tore the belt. The flex shaft issues you are having you may need to just find a slightly larger ball bearing like a bb and slip off the black retaining ring and replace the ball. For more on errors and skips you should do a search for thew username "Digitalwoodshop" as he has covered any of these issues many times.

Hope this helps cause i have been where you are and it sucks.



Stephen

[AskBud]

Turn the machine off and move the Truck by hand and see if you can accomplish the task with no extreme pressure. There could be several reasons for the contact not to be made, or the plate to move stiffly.

1) The Truck travel may be impeded by dirt on the rail, or in the track. Lube on the track or blowing out the inside of the track may help.
2) The Truck belt may not be tight enough (The adjustment is made by changing the tension on the Right end of the track).
3) The Bit Plate may need a spot of lube.
4) Check for a set of wires to be blocking the Bit Plate movement (They are just beyond the Plate, and should not touch). Move them toward the main cut motor. They actually impede the truck from contacting the Bit (touch) Plate with enough force to move it in place.

[arttocad]

Sorry, can't post the MPC file. The artist would have a fit if her work were to be reproduced by someone. A picture is attached below for reference. The two far left cutouts on the dahlia design still need to be cut and the perimeters of both designs.

On the roller, o-ring is in place and I have a whole pack of spares. I'm using tape on the roller edge for every project and there is a clear indent into the tape showing full contact down the length of the board.

The running w/o bit idea is good but as I mentioned, it won't even get through the initial board setup since most of the surface has been carved. I did have the original program running in center of board and the new program setup the same.

47520

[AskBud]

I doubt that your machine has a calibrationl problem. However, to be sure, place a new board in the unit and measure the width and length.

Where, on the original project board, does the unit do its dance?
How far from the top edge are your cut-outs on the flowers? which, if any, have been cut? When the machine did its dance, was one of those areas just forward of the bit?

I'm sending you a private message as well.
AskBud

[Dan-Woodman]

Put masking tape down the middle and across the width of measurement. It' probably detecting the cutout areas.
later Daniel

[arttocad]

AskBud: I don't think it is a calibration issue either and while replacing the torn belt, an inspection of the gears showed no visible signs of damage. I did not spin them around though so there could be a missing tooth hidden from sight.

I will have to try your idea about measuring a different board this weekend. I will be pretty busy with school and work over the rest of the week. On my already cut board, it is measuring the width fine, even over cutouts. I did get it to measure the length one time after trying the tape method and it was the correct length as well.

The image from the designer software shows net board dims almost touching the design. This is done to prevent scaling in the machine and I just cut the board oversize and center on board. Down the 48" length, there is about 3/4" borders on both sides. The ends have 3-1/2" of excess so it had no problem staying under the rollers.

Here is everything that has been cut:
The tree design and all of the flower carving detail has been completed. The surface has been relieved down between 1/16" and 3/8" everywhere on both designs. On the dahlia design, all cutouts with the exception of the far left 2 (closest to the tree design) have been completed. The upper far left design is the one I had alignment issues after reinserting the board but I was going to have the program run over it again and try to hand carve out the mistakes after it was done. The perimeters of both designs have not been cut.

The machine did the dance as it was approaching the upper middle section of the tree design. About the same area mine always goes to for bit calibration. It had the hardest time running over the trees since the carving is so deep. I think the optical sensor is not seeing the board and it is having errors due to that.

Dan-Woodman:
In my original post, I stated that I already tried the tape method to measure the length. Not needed on the width since it had no problem measuring that.

[DocWheeler]

As Dan said, put tape across the board if the width measurement is bad.
For the length measurement, all you need to do is put tape AROSS the ends of the board (about 1.25" or so).

The flex-shaft connection on the top of the "Z" truck can be rotated 180 degrees to give you a new "wear-spot".
There are threads about re-starting a carve - you can "mask" the areas that are already carved in a new mpc.

Try this thread (http://forum.carvewright.com/showthread.php?11792-Power-outage&highlight=zero+depth+region).

[gapdev]

It was my understanding that if you are going to Air Carve or use a new MPC with already carved areas masked out, then you can NOT remove the board?

I tried it a couple of times but I had removed the board and I could never get the machine to align the 2nd carve with the first. I don't think it is accurate enough to do this when the board is removed. Although I've done 2 sided carves that turned out OK. But, I've not been able to get the Air Carve's to work correctly.

Kenny

[RogerB]

I have had the same thing happen to me. My carve was centered I tryed the tape that did not work. What i did was took a paper the same color as the wood.Scrapbooking paper works 12x12 once the reading is done and its carving cut the paper out and let it go. Worked for me. Saved a two day carve.