Cut Pat Problem

[shotgun 6]

Over the last two days I have had a cut path problem. This occurred on the last two projects I was working on. The problem does not apply to the carve or rout as they work perfectly. I set the cut path depth to 0.3 The machine makes the first cut at about 0.7 instead and when it starts the second pass the chuck adapter toches with some pressure the borad and starts scorching. Fortunately, I have been able to stop the machine beforre a fire starts. I have checked and rechecked the mpc. I have removed the plastic cap on the z motor rear and to blow out dust -- there was no dust there. I have 370 hours cut motor time and installed 1.178 last week. I have had this problem twice in the past but they seemed like isolated instances. I have had cut motor errors on occassion as well as z axlis stall but have always been able to work around. I use a Rock chuck and am very cautious about getting the adapter in the chuck correctly.

Any thoughts, suggestions for testing or other help will be appreciated

Bill

[AskBud]

Over the last two days I have had a cut path problem. This occurred on the last two projects I was working on. The problem does not apply to the carve or rout as they work perfectly. I set the cut path depth to 0.3 The machine makes the first cut at about 0.7 instead and when it starts the second pass the chuck adapter toches with some pressure the borad and starts scorching. Fortunately, I have been able to stop the machine beforre a fire starts. I have checked and rechecked the mpc. I have removed the plastic cap on the z motor rear and to blow out dust -- there was no dust there. I have 370 hours cut motor time and installed 1.178 last week. I have had this problem twice in the past but they seemed like isolated instances. I have had cut motor errors on occassion as well as z axlis stall but have always been able to work around. I use a Rock chuck and am very cautious about getting the adapter in the chuck correctly.

Any thoughts, suggestions for testing or other help will be appreciated

Bill

Seeing your MPC may help us.
What kind of wood are you using?

Things to check/do.
1) Use a new bit.
2) is your wood dry, or is it high in moisture/sap? Check with a moisture meter.
AskBud

[shotgun 6]

Thanks, AskBud -- I will attach the the mpc's for review as soon as I can get back to my downstairs computer. The wood is clear pine. After the same thing happened on two different carves I changed the bit and selectled another carve. It did the same thing. I don't have a moisture meter but my basement shop is quite dry and I use electric heat which dries things out pretty much. The first three carves are the bottom, side and top of a heart box I was making for my wife's valentine. The last test carve was the side of the round box that was one of the projects several months ago. I'll get the mpc's up in about an hour.

Bill

[shotgun 6]

Round Box Side.mpcHeart Box Side.mpcHeart Box Bottom.mpcheart Box Top.mpcHere are the MPC's of the Heart Box I'm trying to make. The cut on each mpc resulted in the same .7 depth on the first pass and pressing against the board at the start of the second pass. The fourth mpc is of the side of the round box. I am also attaching an jpg of the top piece which shows the scorch mark at the start of the second cut pass where the adapter is pressing hard against the board and actually indenting about 1/64 (guess) and scorching. It seems like the software is giving the wrong information on cutting.

[shotgun 6]

OOps -- my mpc's didn't attach. Got to figure out how to do that.

[shotgun 6]

Here are the mpc's (I think) Somehow I've missed the Heart Box Side.

[AskBud]

It appears that there is a bevel on the cut-out. Are you using the carving bit to do the cut-out rather than the 1/8" Cutting Bit?
The cutting bit has straight sides.
AskBud

[shotgun 6]

Yes, I used the carving bit in my mpc by mistake. I also failed to invert the surface on the box top.

[Digitalwoodshop]

Without looking at the .mpc lets look and see what can cause this problem....

Since the project Carves Correct and I bet the Text Carves Correct then we know that the Z is working and the machine is finding the surface of the board properly.

The only thing NOT in Common is that the Cut Path OR Depth of Cut, Needs to KNOW the Board Thickness..... To know the Board Thickness with a board less than 14.5 inches wide we use the SLIDING RIGHT SIDE GUIDE. The Bit goes to the Sliding Plate and ducks down in that U Shaped area then shifts Right and touches the RIGHT SIDE GUIDE PLATE. This tells the machine the BOTTOM OF THE BOARD. Based on the Surface and the BOTTOM it makes the correct Z Depth Adjustments to cut the depth you requested. So this leads me to ask....? DID WE LIE to the MACHING....... Causing the ERROR...... HOW may we LIE to the machine?

Well First UP.... Did you remove the Sliding Right Guide PLATE and now the machine is touching the metal further down as the plate thickness is MISSING and THIS is causing your Depth OF Cut error...... Some people in the PAST have stuck a Penny on the Guide Plate to increase the thickness of the Cut Path TABS..... So by the metal Missing you cut DEEPER.....

OR.... You can LIE to the machine when you use a Sled wider than 14.5 and the machine asks you for the PROJECT THICKNESS.... Or The Thickness of the Board ON THE SLED.... We enter that on the keypad.... Garbage in = Garbage Out.... Enter the Wrong number = Error.....

SO let us Know.... Another W A G from AL..... Wild AL Guess not being there..... Just thinking like a machine.....

Good Luck,

AL

[shotgun 6]

Thanks Al. Answers in order:
1. I have not removed the slide plate although I did get a "Ensure Slide Plate Set" error message when I first started carving the project. I changed boards and it didn't appear next time -- then I re-inserted the board I was to carve and didn't get the message again. I have not used any addition such as a penny on the Gukde Plate.
2. I haven't used a sled. My board is a 1 X 8 (0.752 X 7.25 X 14.25 measured by the machine.
I like your thought process. What does the bit touch when it ducks down in the U shaped hole of the Slide Plate to determine the bottom of the board? The best I can dtermine is there is nothing to touch except the bar that the Slide Plate moves on which is way below the bottom of the board
Bill.