Measurement errors

[Patrick Darrigan]

On my four recent projects I selected the "Center on Board" option for the carve location and the CW carved the project but not on the center. I measured three random boards to verify the CW was measuring correctly. It's not. First board actual 12" X 3.5" MDF the CW measured 12.047" X 3.602 not bad. The Second Board actual length 18" X 3.5" MDF the CW measured 19.307" X 3.592". Bad! The third board actual 26" X 2.3125(5/16)" (Oak Plywood) the CW measured 28.493" X 2.439" Worse! Does anyone have any ideas what could be wrong? I did place masking tape on the boards for the tracking roller to follow.

[Digitalwoodshop]

First Post WELCOME !!!!!

You may need to put some tape on the actual board bottom, like 3 strips in total to add to the one you put for the brass roller. Sometimes the board is slippery.

Plus the board can lift up and off the brass roller if the outfeed table is too high.

I like to plan projects and use place on end or corner. I measure out where I want the project to go and leave the board long and cut it off later. It also measures the board only once... With Center you measure the board twice leading to more wear and tear on the machine.

AL

[DickB]

Your boards are all relatively narrow so less grip. What Al said. Check your head pressure. Or, when you crank it down just apply some additional pressure with your hand and see if that helps. Especially with the longer boards I would double check the outfeed tables as Al said. The outfeed rollers should be high enough so that the rollers touch the board and rotate, but not so high that they cause the board to lift. There are also procedures to check and adjust x and y calibration, but try the other suggestions first.

Personally, with that narrow of a board I would use a sled, but then I almost always use a sled.