Not wanting to hijack someone's thread, I started a new one to continue the conversation.

Quote Originally Posted by Kev Williams View Post
TIM-- trade ya my 30 for your 50...

I'm curious as to why you think 50w is overkill, I've been tempted to get a 60w or higher machine, and very glad I didn't get a 20...

What lens you get with that? A 110mm at 50w would produce a very small and powerful beam spot; might be doing more cutting than engraving, or put another way, more melting than 'chewing' and vaporizing. Even a 160 lens (what I have) might be prone to melting with 50w, but I have NO problem with 30w...

You might try de-focusing a bit, to fatten the beam spot, that'll cool it down and may help with the overkill.

Another idea to try-- with my 30w my settings for deep engraving are 100 power 300 speed 30 freq. with 45/135 hatches at .03, and a 0 hatch at .04 with 800/80/80 as a 'cleanup' pass. Here's the thing, if you look at the beam overlap at 300 speed and 30 freq, it looks like this:
Attachment 367158

Now, double the speed to 600 and the freq to 60, and --
Attachment 367159

--the beam overlap is identical, which means the actual engraving/ablating process should be identical, but with less power density due to the increased engraving speed-- but you have nearly double the power! So, I'm thinking you should experiment with higher speed and frequency, maybe you'll be pleasantly surprised! -- or not..? I do know there IS something to this because when attempting to engrave pure copper, I found a very narrow speed/freq setting that worked, and doubling those settings, also worked. Nearly any other settings wouldn't mark the copper a bit.

speaking of focusing, how are you focusing? Red lights or-? About 2 months ago I decided to run a focus-line test, basically 6" worth of 4" long lines spaced 1mm apart, ran at zero power on anodized aluminum while moving the table up & down to find the sweet spot. When I found it, I took a piece of 1/4" thick Cintra, cut a 1/2" wide piece of it and cut it to fit perfectly between the aluminum I was engraving and the bottom edge of the lens housing. That was one of the best 'upgrades' I've done, and haven't used the red lights for focusing since. Last night for example, I engraved dutch oven lids, and with the focus stick, I could move it around and physically and visually find the 'average' focus distance between the low and high spots in the arc of the lid. With the light you have one spot to focus on and everywhere else is just a guess...