Cutting Melamine faced chipboard

[NPW_BESPOKE]

[QUOTE=Ger21;98845]Whether you do it in one pass or two (onion skin) depends on the size of the part, and the quality of your vacuum hold down. (you do have a vacuum table, right?)

Do NOT climb cut, as it will leave a rougher edge. Conventional cut always with melamine (and most wood products).

Gerry
Thanks for the reply. Invaluable knowledge and massively appreciate the advice.

Yes I do have a vacuum table (sorry cant find spec...) and am machining large parts (kitchen carcass panels). Had spindle speed about right but feed rate less than half what you are suggesting



one last question (sorry) regards cutting direction - will I gain anything (mainly cutter lifespan?) from running an initial offset 'climb' pass before doing final dimension profile as a conventional (melamine + most wood materials) ?

thanks again in advance

Nicko

[Ger21]

Imo, no. Conventional cutting will give better tool life.
By doubling the feedrate, your tool life should also nearly double.

[Ger21]

The reason that some people do a climb pass first, followed by conventional, is this.
At high chip loads like this, the cutting forces are pretty high, and with a conventional cut, will tend to pull the tool into the part, resulting in a slightly undersized cut.
This can also happen when onion skinning. The first pass will pull the tool into the material, but the final pass will be more accurate, and leave a small lip on the bottom of the part.
By doing a climb cut first, the tool is actually pushed away from the part, which leaves a small amount of material for the final, conventional cut.
But the climb cut won't cut as clean, especially as the tool starts to wear, so it may leave chips that won't be removed on the final pass.

[NPW_BESPOKE]

The reason that some people do a climb pass first, followed by conventional, is this.
At high chip loads like this, the cutting forces are pretty high, and with a conventional cut, will tend to pull the tool into the part, resulting in a slightly undersized cut.
This can also happen when onion skinning. The first pass will pull the tool into the material, but the final pass will be more accurate, and leave a small lip on the bottom of the part.
By doing a climb cut first, the tool is actually pushed away from the part, which leaves a small amount of material for the final, conventional cut.
But the climb cut won't cut as clean, especially as the tool starts to wear, so it may leave chips that won't be removed on the final pass.

Thanks again Gerry
Great info - this I feel will become a major part of my machines work so much appreciate being pointed in the right direction...

Now to go and play...
Thanks again
Nicko

[EddyCurrent]

One of the best methods to achieve a full depth cut is to use a trochoidal machining operation.
CamBam has an excellent plugin for such cuts if your current software does not.; http://www.atelier-des-fougeres.fr/C...choPocket.html

[Ger21]

There's no need for trochoidal toolpaths when cutting wood, and certainly not when cutting cabinet parts.