settings

[stan kern]

For cutting/engraving are setting pretty well trial and error or is there some guide line for say a 100 watt laser .
I have some guide lines but i also find different woods react different,ie a piece of birch with a laquer finish acts different to say a piece of pine raw.
Also when it comes to glass ,what sort of settings and to my surprise the power isn't like what i thought if you cut something thick the 100% power is not necessarily the answer.
i see a lot of people here with lower power and getting along just fine

[Bruce Volden]

Stan,

There'll be a lot of trial and error while learning the curves. I have a 35 watt and 2 25 watt machines, I RARELY use 100 power and have instead become somewhat profecient manipulating my speed settings as well as pulse settings. This enables me to get the results I desire. When I bought my first machine I was running 100 power and the results weren't always good (centers breaking out of text etc. on wood). I find glass engraves / fractures easily with little power. I run glass, usually, @ 25-30 pwr, 30-50 speed, 150-300 dpi. Just keep playing and learning! Also, get a large roll of painters blue tape as this will come in handy for low power "dry" runs. Also ALWAYS proofread your text. DAMHIKT

Bruce

[Ross Moshinsky]

I run everything at 500dpi. I did a test running from 1000 down to 100. 1000 - 500 no difference in looks even using a jewelry loop. Once I got below 500dpi, I started getting slightly pixelation. So my first suggestion for you is to do the same with your machine. I'm sure your sweet spot will be somewhere in the 400-600dpi range.

Second thing I do is set my speed to 100 and vary my power from there. Sometimes that's not even a remote possibility but, time is money and I want my machine working as fast as possible.

The next step is to vary power. I run Gravostyle 5 and can setup 8 layers at once to run. I put 8 lines of text on a small piece of material and then vary the power on each. If I find I can't get anything to engrave @ 100 power, I know I have to knock my speed down.

If I can get the item in sheet goods, I do this with every piece that comes in my shop. It takes a bit of time, but once its all done, I have an optimized setting for any material I plan on using. Once you get experience, you can look at your other settings on similar materials and start from there to optimize.

Again, run at the lowest acceptable DPI & highest speed. Fine tune with the power setting. Time is money. Keep that laser moving.

[Scott Shepherd]

One of the things I learned about a year after having a laser was that about 100% of the time, I had been using way too much power. I had common settings of 100% speed, 50% power for all sorts of things. I thought everything was fine and life was good. Then, with the purchase of a new laser, it had a manual that showed how to properly tune the laser to a piece of material (it's a method that works on the Universal's that allows for all sorts of manipulation), but in the end, I was finding that 20% power was getting through the material. So I had been using over twice as much power as needed. When I dropped the power, my engraving got a lot sharper as well. All that time I thought it looked great, that was until I saw it done properly and then I realized what I thought was good, was actually blown out.

Many plastics do not take much power at all to break that top surface.

Today, typical power settings on engraving plastics for me are anywhere from 18%-30% at 100% speed. That's on a 45W machine.

[stan kern]

I did whole buch of tests today and i was using 50 to 80% power so maybe i need to try some low power setting and re-do a lot of my tests
But its amazing

[Zsolt Paul]

I have a 100W laser. What is your maximum speed? What focus lenses do you use?

For the most part, you want to use the highest speeds at all times and adjust your power accordingly. In other words, if something looks good 70% speed and 50% power, well perhaps it would look exactly the same at 100% speed and approx 80% power with the added benefit of getting the job done faster.

[stan kern]

thats my problem i know i have 100 watt and i think the max speed is 39in/sec,lens spot size .008 and machine res 250 dpi
Any of this help?

[Dan Hintz]

Several have mentioned that 100% speed is what you should shoot for, but I'll add that it depends on the image you're engraving. If the piece is small, 100% speed may end up being slower overall due to the overshoot. On several small items I've sped up the overall processing time by 25-50% by going to a slower speed with a lower power.

[Daniel Reetz]

One thing that I do is laser the settings onto scraps of material. So if I find out that, say, 100% power, 27% speed and 1100hz cuts 3/16" birch perfectly, I laser those settings onto a piece of birch and then tape it to the wall. That way, I have a huge, instantly visible library of laser settings for all my materials.

[Zsolt Paul]

Good point Dan, that's why I said "for the most part". Small items are definitely an exception often.

Several have mentioned that 100% speed is what you should shoot for, but I'll add that it depends on the image you're engraving. If the piece is small, 100% speed may end up being slower overall due to the overshoot. On several small items I've sped up the overall processing time by 25-50% by going to a slower speed with a lower power.

[Rodne Gold]

GCC machines have a system that stops a lot of overshoot on small items . called Smartact which works quite well.
The literature says it does somewhat compromise the engraving but I have not noticed any degradation using it.
Ideally one wants to balance thruput with engraving quality , however It must be said time based optimisation is only an issue when one has full order books or are doing large multiples. If you have the time , so to speak , then I would opt for quality rather than speed. The issue is that then any costing based on laser time is thrown out the window.

Stan your results look pretty good to me , if you don't mind me asking , how much did that laser cost you?

[stan kern]

the laser cost with indexer,chiller unit small compressor,small blower was 9000 usd
I am not kern's lasers --just a hobby person with that good name