How much ramp is too much (aluminum engraving)

[nateflanigan]

I'm working on refining my technique for engraving text in aluminum, the text is 3.5mm tall, depth of cut 0.2mm. It's come to my attention that I should be ramping in to these cuts even when doing multiple passes (doh!). I've seen a 2% ramp suggested but I'm wondering how this all works together, if I program the tool path to be 3 passes with a 2% ramp in preview it looks like it's really spending a lot of time on each letter, is heat build up a concern? Also, those figures work for a profile tool path with single line fonts, I'm also experimenting with pocketing true type text, since the ramp on that tool path is expressed in distance not angle what would be an appropriate ramp value range?

Thanks!

[Rcnewcomb]

Ramp angle is used in some other CAM packages that are more focused on metalwork.

Trigonometry says with a 2° ramp the bit needs to travel 100mm to move down 3.5 mm.

[nateflanigan]

Why is there no face palm smiley? Thanks, sometimes I miss the obvious. Any insights on how long is too long to be milling about on a cut?