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Rubber spray test with acrylic and glass

I have made some test with rubber spray and transparent acrylic but the results were not satisfactory. Following are some acrylic tests with one coating rubber spray:


After that i tried with glass. That was awesome :slight_smile:


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Hi Salvi,

Thanks for sharing the images.

Are you able to point out the areas that were not satisfactory and we can try to give you some suggestions on how to improve them?

Hi Domenic

Thank you very much for your offered help.

As you can see on the acrylic pictures, I couldn’t completely remove the remains of the black rubber spray, because it was burned into the acrylic.

Also in the power grid you can see that only at a power of 100% (3 Watt) the shades on the acrylic were relatively clean. The surface of the acrylic, where the laser has been lasering, “crumbled” at the other power settings.

With the glass, however, it worked very well in my opinion.

I will do another power grid test on glass to see how different settings will work but will also make some other tests with acrylic.

That glass looks great!
I’m keen to see what difference settings make.


When we engrave into acrylic, the amount of power and speed is critical to getting good results.

  • Too much power will cause the acrylic to melt, hence capturing the surface coating. This may be what you are seeing.
  • The thickness of the coating is important. We found very thin coatings gave us better results.
  • Glass tends to vaporise, rather than melt, which is why the issue doesn’t appear.

Another grid test experimenting with the minimum amount of power required would be worthwhile.

One last suggestion is to use the ‘overscanning’ setting in the cut menu. Set it to over-scan the engraving area by 5-10mm (if possible). This will mean the acceleration/de-acceleration the laser while changing directions will happen in the over-scan area, resulting is constant velocity of the laser while actually scanning. The result of this will be a more consistent engraving across the whole design.

Hope those suggestions help.

Dear Domenic

Thank you very much for your precious  informations. Then i will try to make some tests with less power.
I think, that was the problem for melting acrylic and the remains of the black rubber spray.

In any case i was very surprised about the results with the rubber spray. Very fascinating :slight_smile: Thanks again.


Hello Salvi and Domenic,

The glass looks great! I’d like to etch some microscope cover slips–glass about 0.11mm thick or so, I think–for the purpose of making a break line I can exploit with grozing pliers. Essentially, I want to snap the square into smaller squares. A good etched line is often sufficient for this purpose.

I can’t seem to make a good line another way that I’ve found, so I might try the rubber spray. Are there any brand names I should look for? I’m in the southern African hinterlands, so who knows if I can find anything. What’s the rubber spray’s normal use?



Hi Michael

Thanks :). I have made the glass with rubber spray from MIBENCO http://mibenco.com/fin/liquid-rubber-spray but i think, others liquid rubber sprays used in model making work equally well.

If you are looking on YouTube for example rubber spray use, you will find many application videos where these rubber sprays are used.




Here are some tests we have been performing recently with Rustoleum Peel-Coat.

Applying a thin and even coating is very important.