stepover

[mach3vectric]

I am getting unacceptable tooling lines on my CNC router cutting wood signs.
Does a lower stepover number correct this problem?
Thank you
tamediasd@yahoo.com

[GripUs]

Good morning,
Using a smaller stepover may, indeed, reduce or eliminate the lines. Most folks use a stepover of 7-10% with acceptable results. Since there is no such thing as a free lunch there is a cost to doing that...more maching time. I prefer a longer machining time and less time sanding by hand.

Another cause for the lines is your bit is bent (it doesn't take much and may have come like that) or possibly your router axis is not perpendicular to the table. There are several discussions about how to check that on this forum.

Regards,

Joe

[10cop]

hello,

in fact the relevant parameter is the height of the mark leave by the toll (I think it is called scallop)

I made a excel file but I cannot attached it .xls is not allowed !

I attached a screen copy, you can see the formula. the value are in mm but the formula work with the special units used by english guys ! !

when i want a very clean surface I choose value to get a result of 0.005 mm (5µ) in regard with the tool radius.

Also take into account that as great is the tool radius as good is the surface.

I hope it could help.

bye.

[knighttoolworks]

going along the grain will help a lot too. talking a final light pass too. do a hogging pass then a fast light pass.

[Gnarly Gnu]

Presume you have checked your spindle for vertical accuracy? Obviously it needs to be exactly perpendicular to the bed in both planes to avoid leaving cutting lines with each pass. Also in some cases it may be acceptable to take a minute amount of the outer tips of your cutter using one of those hand diamond sharpening tools (can't remember the name); this will slightly 'un-sharpen' the corners of the cut which helps the problem but is not desirable in every situation of course. I only do this on my big flycutter.