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Skydeals
16-10-2015, 09:00 PM
Hi
Bit of a newbie here but Im using a v bit to engrave into mdf and I cant get a smooth finish on the surface. Instead I get a finish with the edges appearing shredded. Could anyone suggest a how to obtain smooth edges or point me to a thread explaining how to.
Cheers

njhussey
16-10-2015, 09:04 PM
Good finish is mostly down to speeds and feeds and the stiffness of your machine. What you got and what speeds and feeds you using?

magicniner
16-10-2015, 09:21 PM
Most finishing strategies involve ball end cutters

Skydeals
16-10-2015, 09:29 PM
Good finish is mostly down to speeds and feeds and the stiffness of your machine. What you got and what speeds and feeds you using?

Ive got a Basic 540 cnc. The feed is at 45inch/min and RPM of 15000rpm. Even when reducing feed I still get the same finish.

Skydeals
16-10-2015, 09:33 PM
Is it possible still to get a smooth finish only when cutting 2D designs to a single depth throughout, with the V-bit. Ive seen outputs on youtube that have a smooth finish with the V-bit.

Christian Knuell
16-10-2015, 10:01 PM
Hi,

MDF is usually quite nice to machine and forgives a lot in terms of feedrate and rpm.
Is your tool sharp enough (cheap ones are often dull by design - good V-bits can be quite pricey)?

You may try to cut in 2 passes to improve results - just start the program twice:

The first time zero your Z-axis 0.1mm higher than required.
Second time zero your Z-axis correctly, use max rpm and moderate feedrates.


Christian

Neale
16-10-2015, 10:02 PM
Also depends on the grade of MDF - some is like cold-rolled cardboard and will never give a decent finish.

Skydeals
16-10-2015, 11:28 PM
Thanks. Il try and see if running the cut twice works. It could be the bit, I got it for under 5.