Why is it cutting like this?

[Rob Mulgrew]

This is my 2nd CW and this machine cut like this right out of the box but I never had time to mess with it yet being I don't do a lot of cutouts. It actually carves raster just just fine, even vector letters are fine and right where they should be but any cutouts are all over the place on each end. I'm only going .30 per pass and its a sharp bit into pine. I'm using masking tape on the bottom and I don't see where it's losing contact with the roller.
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[bergerud]

I do not believe that is due to loosing contact with the brass roller. I think, if you look closely, you will see that the tracking went wrong during the cut along the side by the brass roller. The vibration of cutting so close to the brass roller seems to confuse the brass roller encoder. I always make cutouts which go near the brass roller up on a sled.

[Rob Mulgrew]

The cut travels past where it should on each end. It actually is perfect on the roller side and the side against the sliding plate. Each pass seems to go out a little farther than the last on the ends. Does it sound like a board tracking roller problem? I could swap out the tracking roller with my other machine but really dont want to do that if I dont have to.

[bergerud]

The cut travels past where it should on each end. It actually is perfect on the roller side and the side against the sliding plate. Each pass seems to go out a little farther than the last on the ends. Does it sound like a board tracking roller problem? I could swap out the tracking roller with my other machine but really dont want to do that if I dont have to.


The poor tracking happens as it cuts the roller side. The length of the cut is what is wrong. You only see the result in the end cuts.

When the brass roller data is determined to be faulty by the controller, the tracking is handled by the x motor encoder data instead. The x motor tracking is uncalibrated and very poor.

[Rob Mulgrew]

That makes sense. Thanks for the explanation. I'll try a sled and see if it makes any difference for the next one. Thank you

[DickB]

A sled with 1" rails will keep the cutting bit away from the roller and avoid problems. A 3/4" plywood base will add mass and dampen vibration. I use a sled on every project that is 12" wide or smaller. Avoids scrap wood and yields consistent results. 2nd best advice after a top-mount dust collector.

[Digitalwoodshop]

I am going to be "Difficult" and go with the board loosing contact with the brass roller.
By depth of cut, can you tell if the cut is shifted to the left in the picture as in both ends shifted toward thee head of the board?

How much wood stayed under the rollers?

Was the board held to the table by both rollers the whole time and never holding the board by one roller? This is when the board lifts when held by one roller and loosing contact with the board and brass roller.

Did you have masking tape on the bottom of the board at the brass roller edge to give the brass roller something to bite into?

IS the under side of the board edge perfect? No missing wood that would confuse the brass roller when the wood was missing?

Any chance you vacuumed the machine and sucked the rubber bumper from under the brass roller?

Are the intake and output trays level to the belt deck? A high out feed table can lift the board off the brass roller.

I am just falling back on the "traditional" reasons.

Did doing the project on a sled work?

******* Can LHR chime in on the X Drive Encoder taking over for the Brass Roller ??? Never heard that before just want some clarification and in what versions this works in? ******* Thanks :)

AL

[Rob Mulgrew]

I always leave the 3.5" on each side and select stay under rollers. I do use masking tape on the roller side and I cannot see where it lost contact with the roller. I do not think it's user error on this one. I've carved thousands of signs over 5 years and have 2 machines. With my old C machine I never needed masking tape and did not have this problem. I will try a sled but don't have time right now. Everything else carves fine. Even if I put in a 60v or 90v bit and carve a border all the way around the sign it carves fine and lines up fine. It's only on the cutout that it drifts past where it should on each pass.

[fwharris]

With the cut path that close to the brass roller it could causing the skip. Did you get a warning message about needing to jog because of the bit coming in contact with the brass roller when up uploaded the project to the card? If you did when the cut path comes to the area of the brass roller it will add a tab there. That bit of movement of the board advancing looks to be close to the cut off set. I try to leave a minimum on 1/2" of board edge when I do cut outs on boards that are not in sleds.

[Nick68]

Your not alone...im having same issue. Moving the cut path 3.0in away from brass roller, decreasing depth to .125, adding sand paper to underside of board, adjusting head pressure, squaring the squaring plate, building a sled, using the 4.5" rule, masking tape or no tape, checking the x motor gears/teeth, realign the head, remove the rubber o ring from brass roller/reinstall, trim .250 off of front/keypad rubber belt. Have yet to remove the cut motor and attach it to an external self, as well as, gut the machine of all electrical components and mounting said components in a box located away from machine. So, instead of gutting the cw I order new parts...belts, brass roller, eye balls and bit. I suspect the rubber belt is slipping because they, the rubber belts are out of spec/to big. O, i did adjust the trays. Producing much scrap, makes for a warm fire pit lol

[Nick68]

I also purchased the Universal sled. I guess I could add tension to the rubber belts by adding 2mm washers to the springs located in the x feed trays.

[Rob Mulgrew]

I will try moving the project over and using a bigger board but I've made tons of these signs on my older C machine with the same settings, same design, which all worked fine. My thought was also that it had something to do with the rubber belts because with the sandpaper belts it worked just fine.

[Digitalwoodshop]

I always leave the 3.5" on each side and select stay under rollers. I do use masking tape on the roller side and I cannot see where it lost contact with the roller. I do not think it's user error on this one. I've carved thousands of signs over 5 years and have 2 machines. With my old C machine I never needed masking tape and did not have this problem. I will try a sled but don't have time right now. Everything else carves fine. Even if I put in a 60v or 90v bit and carve a border all the way around the sign it carves fine and lines up fine. It's only on the cutout that it drifts past where it should on each pass.

Wow, that makes for a much clearer picture....

So my first thought after all this is that I wonder if 1. Your head is level? and 2. The 4 screws on the bottom of the machine holding the 4 smooth posts are tight...

A WAG.... Wild AL Guess...