First engraving test :)

[cropwell]

Hi Dave,

Engraving looks good !

I find the problem is usually getting the material flat enough to the X-Y plane to get an even DOC. Taping down to a sacrificial MDF surface which I have skimmed generally works. I use chisel engraving bits with a 0.2 mm flat on the end.

Here's a couple of examples, both are low res photos. The first was done with the chisel point engraver, it is 60x20 on .5mm brass with .1 DoC. The second is done on fibreglass PCB using a 1mm two flute cutter to cut through the copper. It looks good with backlighting but the furnace is never switched off long enough to put that in ! I got the picture by capturing a webcam image, so that too is low res.

[Davek0974]

Nice, I cant be too far off then, what sort of feed rates do you use?

I have a pack 10 30 degree tapered bits with 0.1mm tips - too fine??

With a DOC of 0.1mm do you do that in one hit?

[cropwell]

Nice, I cant be too far off then, what sort of feed rates do you use?

I have a pack 10 30 degree tapered bits with 0.1mm tips - too fine??

With a DOC of 0.1mm do you do that in one hit?

a. 2540 mm/min
b. depends on what you are doing
c. yes

Cheers,
Rob

[Davek0974]

Guess i was running a little slow then at 165mm/min ;)

[Boyan Silyavski]

Many people really miss the main point. All really depends on the stick out of the tool. The shorter the stickout the faster you could go even with 1/8" tool. i would greatly recommend HSMAdviser. Not only its a great program, but most of all opens your eyes about when you change this and that how to achieve the even most important main point of all this- better material removal rate . At the end id does not matter what you do and how you do it. The removal rate matters.

[Davek0974]

Thanks Boyan, I have subscribed to HSMAdvisor but engraving seemed to be throwing up some very odd figures.

[John S]

Dave,
I think also you have backlash issues with the machine.

In the close up you have backlash marks at the top of the o and c and bottom of the d, u and s

I would worry more over this than speeds and feeds.