design error need advice

[sjmoore69]

I designed this carve for a deck on a cedar strip canoe. I laminated some 1/4" ash on top of some 3/4" walnut and spliced two pieces together to make a 14" wide board. After tweeking the design to get the right look, I taped the boards into a sled to get the widest piece possible. The carve went fine until about 10% when the depth began increasing in increments to what looks to be around 5/8" depth and carved into the walnut dowels I used to splice the boards. Is this the result of the subtractive merge style or the product of the 1/4" feather? It would seem that the depth of the two carve areas are added together. It looks perfect in the designer but obviously isn't working for me on the CW. I'm wanting the cross to be profiled in the ash with the rest carved into the walnut.
Any suggestions on how I can achieve this would be greatly appreciated.

Steve

[DickB]

I don't think the problem is with your design, I think you have a z-axis issue. Check for binding in the z axis and dust in the encoder.

[Digitalwoodshop]

Like posted above likely a Z Mechanical or Dirty Encoder issue.

1. Remove the back of the Z Encoder and inspect. 1. Dust and 2. if the clear plastic disk can spin free of the shaft. A drop of Super Glue has fixed this in the past. Just a drop....

2. Dust and dirt in the Z Belt Cogs or even on the roller rail bearings. Do you have Dust collection? The "No Mans Land" the area between the lower and upper bearing then the head is all the way up and all the way down can trip you up.... You must wipe between the bearings while going up and down.

3. FSC Cable... It supplies the power to the Z and the return pulses... When a wire breaks in the 14 pin cable the head can loose pulses due to the broken wire and the computer will KEEP moving the head until it counts the correct number of pulses... Moving it deeper and deeper into the board. THE TEST... Move the head to the Top Mechanical Pin and call up the Z Data on the LCD. Now move the head up and down top to bottom a few times and return to the top. Should return to 0000 when done. IF NOT dirty encoder or loose disk. Do the Same Test but this time move the Y back and fourth as you go up and down... THIS checks the FSC Cable for Intermittent wires....

4. A FROZEN Z Truck Bearing can cause a DRAG on the way UP and the up NOT completing before it goes down again hence deeper and deeper... Mark the bearing with a marker and roll the head up and down. Bearings CAN SLIDE on the rails... Usually the Lower LEFT bearing is the frozen one due to sawdust being thrown at it.... WD-40 can free it up but CAREFUL as WD-40 when it gets on the WOOD prevents finishes from sticking.

5. And Last... The FLEX SHAFT..... On the UP Stroke the FLEX Shaft can CATCH on the top Plastic Cover.... Usually a WORN BB mark from the Top Hat.... A Worn Flex Mid Life Fix is to Rotate the Top Hat 180 degrees.

Good Luck,

AL

A quick test before and after is to draw some small circles and make carve regions and do a test carve.

[sjmoore69]

Thanks guys.