cutpath problem

[myshop1044]

I seem to have x direction shift on the second pass of cut path on 2different
projects. see attached. I was there both times, because it cut into project while I was not there
wasted a 3 hr. carve.
Is it possible the cutting bit is getting worn that far up on the bit. I do 1/3 pass on a 3/4" board.
attached are the pictures and the project.
Please feel free to play around with the mpc.
Any help would be great.

Perry B.

[lynnfrwd]

Your boards do not seem to have the 3.5" on each end to stay under the rollers. Are you using a jig with the 3.5" in it? Looks like it lost tracking after popping out from under rollers or check outfeed trays to make sure they are lined up correctly.

[myshop1044]

I used the option 2, not to stay under the rollers both time, could this have cause that problem.
the boards were just enough to fit the projects.

[fwharris]

I used the option 2, not to stay under the rollers both time, could this have cause that problem.
the boards were just enough to fit the projects.

That would be my guess.

[bergerud]

I can tell from the line on the carve that you did not stay under the rollers. In my experience, the effort of pushing up the roller while cutting causes either the board to slip on the belts or the belts to slip on the belt rollers (I have not done an experiment to determine which). The brass tracking roller data is used to make small tracking corrections while routing. If, however, the discrepancy is too large (belt slip for example), the brass roller data is ignored and the x encoder taken as the only reference. The cut will then be off by the amount slipped.

For accurate routing, head pressure, staying under the rollers, a sharp bit, and a healthy x drive system are all important.

[jakab]

And if you carve it again, make sure you spell "Reunion" properly

[myshop1044]

Thank you for your input, my over site.
This brings up a good question. What is option 2 for(don't stay under the rollers)?
When do you use this feature? If it can cause the problems I saw.
maybe I missed something, I have always used stay under the rollers and this time I had about 2 extra inches
in scrap wood to use.
any input would be helpful.
Perry B.

[SteveNelson46]

Thank you for your input, my over site.
This brings up a good question. What is option 2 for(don't stay under the rollers)?
When do you use this feature? If it can cause the problems I saw.
maybe I missed something, I have always used stay under the rollers and this time I had about 2 extra inches
in scrap wood to use.
any input would be helpful.
Perry B.

I'm sure there are many instances where the project doesn't need to stay under the rollers. I use the Carvewright to cut out 1/8" clear plastic templates for my lathe duplicator. I make the actual board (plastic) just slightly larger than the project and it really doesn't matter if one end pops up a little. It's just a shallow vector cutout.

EDIT: In fact, for most of my carves I use the option to "Not Stay Under The Rollers" and "Center Project On Board". Then I make the actual board 7 -8" longer than the project.

[fwharris]

Thank you for your input, my over site.
This brings up a good question. What is option 2 for(don't stay under the rollers)?
When do you use this feature? If it can cause the problems I saw.
maybe I missed something, I have always used stay under the rollers and this time I had about 2 extra inches
in scrap wood to use.
any input would be helpful.
Perry B.

If you select "stay under rollers" the machine will add 7" to your projects size and if your board is not at least 7" longer you either have to scale the carving or load a new board.

Saying "NO" the machine is only looking for a board at least the size of your project. The trick is to always have a board, add on pieces, sled, carrier board or rails so that you are at least 7" longer than your project so that you will still be under the rollers to prevent tipping and maintain good contact with the tracking sensor.

[Digitalwoodshop]

9:00 PM... Just getting to my computer and you guys have all the right answers.... so to recap...

The 7 inch rule of wood... Say YES to Stay Under rollers and don't have 7 extra inches of Physical Wood Longer than Designer Length then it will TAKE it from the Designer Length and Scale The Project....

But Here it looks like since the wood was only being held by ONE Roller, the wood lifted and lost contact with the roller....

It's ALL About the Brass Roller... Once the board looses contact, the board is OUT of POSITION and will never recover...

AL