Pine Box - Halo issue

[Robin Bernstein]

Hi,
I'm hoping someone can help. We offer pine 1 bottle and 2 bottle wine boxes that we etch for customers.
We use an epilog 30 watt laser engraver.
To prep - I place masking tape -(R Tape Plaque Masking Tape) to avoid the halo effect. But it doesn't always work.
Our settings currently are 25 Speed/100 Power, but sometimes we lower the power to 90.
I really think it just depends on the wood - even if it's all pine.


I'm just wondering is there any way to eliminate the halo completely? Are there any tricks or settings that I'm missing?

I attached an image. On some letters in the pic the letters show a halo.

Thank you in advance for your help!

[Terry Wade]

When I'm engraving wood I notice that I almost always have a residue which I believe is caused by the moisture present in the wood itself and there's nothing I can do about that. What I do is keep a can of Denatured Alcohol around and just simply wipe away the residue with a rag and DNA which dries pretty quick and the residue is gone. Just what I do that works for me....

[Ross Moshinsky]

What tack transfer paper are you using? It should be high tack and applied with a squeegee to make sure it's really stuck on. It's also a good idea to apply and let it sit for a period of time so it really sticks down.

Ultimately, on something like that, you're better off ditching the transfer paper. If you take away the transfer paper, you can get the same look running at 100 power and 40-50 speed. Then just do a quick sand with a random orbital sander at 220 grit and you're good to go. You'll save a bunch of time doing it this way and the results should be better.

[Robin Bernstein]

Thank you! I'll try that. I wonder also if the glue from the tape is cause it to halo. But it's also strange because it doesn't always happen.

[Robin Bernstein]

We use this masking tape by R. Tape. We get it from laserdark.com It says it's high tack. The results vary. Sometimes I get a great etch and other times it's terrible. But also that may be because of the wood.. I'm going to try your suggestion. Thank you!

[Ross Moshinsky]

You're engraving what appears to be medium to low grade pine. You're not going to get consistently great results like you will with something like alder or maple.

Also it's a sappy wood which is causing the goo. To me, your problem is the masking isn't really firmly which is allowing it to seep under the mask instead of stay above it.

Even then, when talking about unfinished wood, it's infinitely better to simply engrave and then sand after. It's faster and takes care of this problem 100%.

[Kev Williams]

What's your resolution settings? I rarely if ever run wood at higher than 300 in both directions, some wood and most leather I run at 200...

How is the smoke extracting? If you can keep the smoke from being pulled across the surface of the wood, it'll help.

That in mind, do you have air assist?
If yes, are you using it?
If so, don't, and check the results...
If not, then try it, BUT, regardless you want ONLY enough air to push the smoke away from the cut and lens ONLY, too much air pressure will push the guck right into the wood...

If you don't have air assist, you might consider trying a small fan right in the cabinet- it would have to be set lower on the table than the lowest point of engraving so the gantry won't hit it... I used to do this when engraving raw leather in the Triumph, the light breeze gently moved the smoke away and virtually eliminated the soot and halo. I've since rigged up a 1/8" air line from the pump I got with the laser, it runs wide open without restriction, but using 1/8" hose there's no pressure, it's just like blowing smoke away with your mouth. It works with leather and what little wood I engrave...

Another option, run 2 passes, same power but at near twice the speed. it may take longer, better better results and not messing with tape usually works out better in the long run!

[Robin Bernstein]

Thank you for your reply! Our resolution is 600 dpi. It's the same dpi that the instruction manual advises. But we have tried different dpi.. I don't think we went down to 200, but definitely tested at 300 and 400 dpi.

We have an exhaust fan venting out of the building. We did not get the air assist.

I think the suggestions have been great. It's very helpful. My hesitation of going over it twice is the time involved. We are in the middle of holiday ordering and with so many etching jobs to get out, I don't know if we can do it. I think our best bet would be to try the dpi and test that. But also try the no tape and then sand after and see what our results are. I think if we had more lead time and less orders, I could definitely experiment more with it.

[Real Mercier]

On the Epilog you have the option to engrave from the bottom up. This way you are not pulling the smoke up over the engraving.

Hope that helps

[Kev Williams]

If you're running at 600dpi, running 2 passes at 300dpi will run at nearly the same speed- at 400dpi you won't be adding that much more time to get pretty much the same results; if it takes 2:00 minutes to run 1 pass @ 600 lines, then it'll take roughly 2:45 to run 2 passes @ 400 lines. And if your machine is capable, run the Y at 400dpi and the X at 600dpi, increasing the X will somewhat increase the material cut and adds zero extra time. However, do som experimenting, 400 or even 300dpi X may give good results with even less smoke...

This much I've learned- If I'm spending 5 minutes of my time cleaning up after a 5 minute job, it's worth it to me to increase the engraving time if it'll decrease MY time ;)