Too wide recess

Does anyone know why I get a wider recess
though I have specified the same as the material thickness


Did you calibrate your machine. If you are using the stock setting in GRBL they may be off just a little bit causing it to be wider.

Sorry Sir
I´m to newbe with this to understand what it means by “nominal”
Please explain to me

I have not done any calibration at all
Please explain the stock setting for me

Bits have a nominal (normal) size. If the diameter is over sized your cuts will be wider than expected. Not all bits are created to close tolerances. There are numerous websites with bit sizes with decimal equivalent so that you can check the bit with calipers or a micrometer.

The material are 6 mm thick, and I have used 1.5 mm bit
and I did cuting outside the line

This is the pattern:

I do have a micrometer but how do that help me ?
the bit is smaller than the slot

how do I check that

Think of it this way. Easel thinks your bit is 1.5mm, so if you cutting outside the line Easel moves the bit .75mm to the outside of the line for the cut. If your bit actually measures 1.6mm, Easel still moves the bit .75mm, so your cut would actually be .05mm inside the line. (1/2 dia of bit as measured = .80 - .75 = .05mm).

Use your mic and measure the dia of the bit at the flutes not the shank.

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This is probably the best way I can explain it. Robert does a great job.

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Several things at once are happening to make your slot a little bigger than your wood thickness.

• Your spindle isn’t perfect, it can wiggle a little bit.
• Your bit isn’t exactly the size it’s supposed to be.
• It’s also not perfectly straight.
• Your material isn’t perfectly uniform in thickness, nor is it as thick as advertised.
• Your X-Carve isn’t capable of truly perfect positioning.

All of this is only a few hundredths of a mm here or there, but it all adds up.
Some ways to help fix this:

• Measure your bits, type that number into Easel.
• Measure your material in several places. If you have access to a jointer and thickness planer, use them.
• Tune and calibrate your X-Carve. There are several videos linked throughout this forum with great explanations how to do this.
• Get a high-precision collet for the spindle. This will minimize how much the bit is allowed to wobble.

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