CNC Router Aluminium surfacing

[dfox1787]

I think there are many methods, tools and theories of what is "best". Personally I am using simple four flute, 6mm diameter bits at 18-22krpm and that works fine for me. The surface is very smooth and shiny. I can't use larger ones because I have ER11 spindle. I would not dare using any fly cutters with these high speed spindles.

Thank you. Thats the issue i am having. Very limited collet size. Ive used a standard endmill before but i seem to get tooling marks that have a slight texture to them. not sure if this is machine related or if its normal.

[A_Camera]

Thank you. Thats the issue i am having. Very limited collet size. Ive used a standard endmill before but i seem to get tooling marks that have a slight texture to them. not sure if this is machine related or if its normal.

Close your eyes and feel the surface with the tip of your finger or the nail of your index finger. If you can feel the pattern then it is machine related and not good. Otherwise it is normal. There is always a visible pattern unless you polish the surface. Of course, you must use sharp tools.

[russell]

Don't use coated endmills on aluminium. You will tend to get build up on the tip and poor finish. I find these work well. Also make sure you have a good grade of aluminium for machining - it makes a world of difference.

Russell

[Zeeflyboy]

tooling leaving ridges means your spindle is out of tram in one or more axis (ie it is not perfectly perpendicular to the X/Y axis)

The smaller the bit, the less obvious this will be so one solution is to use smaller bits and smaller step overs but you will never get a really smooth surface unless you spend some time shimming your spindle into tram (or if your machine has adjustable tram then even better than shimming of course).

As mentioned above you will always have visible swirls/marks but if the surface feels ridged then look to tramming as your solution. With good tram, it should be relatively easy to polish away the tooling marks with some light sanding.