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View Full Version : Etching Pyrex, Quartz, Acrylic, & Polycarbonate



Travis Centers
02-09-2016, 9:51 PM
Hello,

I am new to engraving and was wanting to ask you guys about etching Pyrex, Quartz, Acrylic, & Poly-carbonate. Do any of these materials have any big issues with high quality etching?

I have been calling several different laser engraver manufacturers such as Vision, Trotec, Full Spectrum, and ect.. None of them could really tell me about etching and different types of glass.

One more thing, What machine do you guys recommend? I can only afford the lower end models and I know you get what you pay for. My choice from what I have seen so far was a Trotec Speedy 100 with a Rotary. I don't know that I can do 10k though.

Are there any other good options out there for a production rotary engraving machine that are a little more affordable?

Thank you, any help is much appreciated.

Looking to etch something very similar to the size of a Pyrex Guitar Slide. http://www.stringsdirect.co.uk/images/jim-dunlop-usa-203-pyrex-glass-large-guitar-slide-p6824-6441_medium.jpg

Braden Todd
02-09-2016, 10:01 PM
From my experience Pyrex makes a mess with a laser, large chunks come out of etched area and I never got a good mark. Also is the same as glass torch glass blowers use

Did one Quartz piece but I sandblasted it, great results there but not sure on the laser. True blown Quartz glass is no where cheap so I didn't risk it.

Cast acrylic is good, extruded is bad.

Polycarbonate is is tricky and results can vary on your tube and frequency. I suggest testing from supplier before assuming it works. My helix makes a poor mark but my ext is great, in the end it seemed to be the difference in tubes and the 60watt didn't work well. You can get a nice white mark, but if overdone you get a yellow not so pleasant mark.

I love my my epilogs and would recommend their machines, look for trade show specials for pricing breaks.

Good luck!

Travis Centers
02-09-2016, 11:08 PM
So you are saying that Pyrex can be etched, but the dpi will be much smaller because of the fractures being not as controlled? I read somewhere about using dish washing liquid to coat it before etching.
I have seen a few pics of laser engraved pyrex, but I haven't seen anything in super high resolution. Ex. http://bentedesigns.com/images/recipe_dish.jpg

Really as long as I can do logo's and letters I will be fine. The Genre of items I will be working with don't really require picture perfect etching. So, I guess it will work for me unless there is something I don't know about.

Thanks for the info thus far. I will see if Trotech or the other guys will etch a sample and ship it back to me.

Kev Williams
02-10-2016, 12:33 AM
I've been engraving Pyrex for Xmas presents for years, I haven't found it any better or worse than any other glass. My 40w Synrad LS900 when using the right settings engraves glass wonderfully. But, my 35w Synrad GCC Explorer, I can't get it to engrave glass for squat. Fractures glass horribly.

HOWEVER- So did my LS900 until I found the right settings. But trying to duplicate those settings with the GCC is proving to be very frustrating.

With my 80w Reci Triumph, if the glass will take the heat (most won't), crank it up and it actually melts the glass, and the results are fantastic- if the glass doesn't break. So far, the only glass that I've had success with is 1/2" or thicker. Thinner glass breaks. And power down to normal ranges, and I get bad fracturing.

Finally, with my now-gone 25w Synrad ULS, I got so-so results in glass, but because of the low power I didn't experiment with it all that much.

So out of 4 different machines- 1 glass and 3 Synrads- only the one has ever delivered top-notch results...

Therefore, I've proven, to myself at least, getting good results engraving glass has pretty much nothing to do with the glass itself, and almost everything to do with getting the laser beam and the glass to cooperate with one another.

Moving on to acrylic- Most machines will engrave text and detailed graphics decently. BUT- start engraving out large expanses, and you'll like find "banding" will ruin your day. Sometimes horizontal, sometimes veritical. It's difficult to find a cure for banding, my LS900 is horrible sometimes. Sometimes the fix is to use the same settings as I use on glass, but- detail can sometimes suffer (glass is fairly forgiving). But going back to my little ULS, that machine was phenomenal at NOT banding. I could engrave a full 12 x 18" sheet pure 'black' and there wouldn't be a hint of banding. If only all machines were like that...

Finally, engraving polycarbonate is no fun. Unless you have all day to make a bazillion low power passes, best I've ever gotten is reasonably decent 'utilitarian' engraving with yellow stains.

Travis Centers
02-10-2016, 1:53 AM
It sounds like I would need to have someone give me a demo with my own materials. If not choosing a machine would be a blind decision.

I am looking to etch something like this.

Looking to etch something very similar to the size of a Pyrex Guitar Slide : http://www.stringsdirect.co.uk/images/jim-dunlop-usa-203-pyrex-glass-large-guitar-slide-p6824-6441_medium.jpg (http://www.stringsdirect.co.uk/images/jim-dunlop-usa-203-pyrex-glass-large-guitar-slide-p6824-6441_medium.jpg)

Starting to wonder if I shouldn't just go with etching cream and a vinyl cutter. The problem will be production speed.

Mayo Pardo
02-10-2016, 3:08 AM
Sorry I can't offer any additional help with direct experience for the materials mentioned but seeing that pyrex dish with the recipe etched into it I'm wondering if that will make the dish more likely to fracture when put to the intended use?
Pyrex has always been known for the ability to withstand drastic changes in temperatures (fridge to oven).
Isn't laser etching glass somewhat like using a controlled glass cutter that allows you to snap the glass at the mark?

Travis Centers
02-10-2016, 4:21 AM
Yes very true! Just like using a diamond to cut it before you break it.

Like I was saying though this is for something that isn't going to be stressed to that type of heating and cooling. Something more like a guitar slide.

I would guess that you would have to Anneal it in a Lehr afterwards.

Maybe buying a Vinyl cutter to make a mask, wrapping the object, and sand blasting the cut areas would be a better idea.

Much more time consuming, but way less expensive.

Bob Davis - Sturgis SD
02-10-2016, 5:09 AM
Yes very true! Just like using a diamond to cut it before you break it. Like I was saying though this is for something that isn't going to be stressed to that type of heating and cooling. Something more like a guitar slide. I would guess that you would have to Anneal it in a Lehr afterwards. Maybe buying a Vinyl cutter to make a mask, wrapping the object, and sand blasting the cut areas would be a better idea. Much more time consuming, but way less expensive.

Travis,

In my limited experience with vinyl cutters, you won't get that kind of detail with a vinyl cutter. But there are two alternatives: 1) use photo resist with light sensitive emulsion to create your sandblasting resist, or 2) use laser mask resist and have someone with a laser put your design into the resist. You would normally have the laser mask resist already attached to your object before you laser it. If you don't, the carrier sheet over the resist melts together with the resist causing a big mess.

If you are putting the same design on many items, the folks at Rayzist would be happy to create the photo resist for you. That may not be practical if your design changes with each item.

Bob

Mike Null
02-10-2016, 7:05 AM
I did the attached with my Trotec laser but I think your answer is sandblasting. You can work with all the materials you mentioned, buy professional equipment, and do a better job than a laser will do. I agree that photo resist will provide the detail but vinyl will give you other options at a modest cost as well.

331382

Travis Centers
02-10-2016, 1:48 PM
Travis,

In my limited experience with vinyl cutters, you won't get that kind of detail with a vinyl cutter. But there are two alternatives: 1) use photo resist with light sensitive emulsion to create your sandblasting resist, or 2) use laser mask resist and have someone with a laser put your design into the resist. You would normally have the laser mask resist already attached to your object before you laser it. If you don't, the carrier sheet over the resist melts together with the resist causing a big mess.

If you are putting the same design on many items, the folks at Rayzist would be happy to create the photo resist for you. That may not be practical if your design changes with each item.

Bob

Bob,

Thank you so much for mentioning this. Wow, I had never seen or known sandblasting resist existed. I watched a rapidmask tutorial on the Option 1 you mentioned. It looks to work very well even with halftone Inkjet negative photos transferred to high detail 2mil resist via UV light and then sandbasted lightly.

Option 2, What would be the advantage of the Lazermask over just going with a High Tack 4mil Photo Resist? (I am guessing production time?)

Thanks so much,
Travis

Mike Null
02-10-2016, 2:03 PM
There is no advantage to Lazermask unless you want to use the laser to make the mask for blasting.

Travis Centers
02-10-2016, 6:22 PM
I had a dealer today call me about purchasing a Geograph. My bank account can't touch their production laser machines, but he was wanting to show me some of their rotary engraving machines that use bits.

I have never seen one. I plan to go to the trade show at Gaylord Opryland Hotel this weekend and take some sample pieces and designs with me.

I am pretty much leaning towards Sandblasting thus far. It seems much more like a fail safe and affordable idea.

I would only need a Sandblaster, Inkjet printer, UV Light, and I believe a Kiln to re-temper the glass.

Gary Hair
02-10-2016, 7:11 PM
I would only need a Sandblaster
Make sure you get a pressure pot, not siphon feed.


Inkjet printer, UV Light,
A standard BLB (black light bulb) will work, I've been using them for over 8 years.


and I believe a Kiln to re-temper the glass.
If you do a light surface etch then I don't think there is a need for this.

Mike Null
02-11-2016, 7:01 AM
I see no need for a kiln.

Travis Centers
02-13-2016, 3:15 PM
Any Brands of sandblaster you guys recommend or recommend to stay away from? I know you get what you pay for, but I am not sure how much I should be paying for a blaster.

I will be working with nothing larger then a bottle so I don't need huge space also I do have fairly large hands though.

What polymer seal coating solution do you guys recommend? (This will be a surface that is touched quite often)


Thanks for all the replies. What an awesome community of people.

Gary Hair
02-13-2016, 7:09 PM
Any Brands of sandblaster you guys recommend or recommend to stay away from? I know you get what you pay for, but I am not sure how much I should be paying for a blaster.
For the work you are doing I would recommend the red Harbor Freight cabinet. I have two of them and have been using them for about 8/9 years. For bottles and glasses, you would be wasting money on anything larger or more elaborate. Get a small pressure pot, 20# is fine, and use 150-180 grit aluminum oxide - it will build up static and shock you a bit, but I find it keeps me awake when I'm blasting that 100 glass job... I use their green dust collector to vent outside, with fine media you won't get much dust blowing outside.


I will be working with nothing larger then a bottle so I don't need huge space also I do have fairly large hands though.
I'm 6'4" and have pretty good sized meathooks as well, the HF cabinet has what I believe are standard size openings - my hands fit through fine and the gloves are actually a bit big!

You can look at Crystalblast and Rayzist setups, but for the work you are doing I think they are several thousand dollars of overkill.

Travis Centers
02-14-2016, 1:28 AM
my hands fit through fine and the gloves are actually a bit big!


That is one thing I was really worried about.

Gary, Do you have a favorite Nozzle size for small objects? Do you use a Feed Blaster Gun? Sorry Man, I have
never done this but I am a quick learner and you don't have to tell or show me more then once. I have been
on YouTube for a good while watching tutorials on sand blasting.

I believe after some time I will be getting a Laser also. Epilog sent me a wood and
metal sample item and I could not believe it was done with a laser. Just amazing
quality and very small detail. At some point I will get into laser and metal also.

Mike Null
02-14-2016, 7:58 AM
Having had both the HF and the Rayzist equipment I would not buy the HF again. Yes, it will save you money and do the job but the Rayzist or other pro unit is far superior in terms of dust control (a major issue) lighting, space and recycling the medium. I would also go for silicon carbide as my medium. Longer lasting, sharper and will not produce the very annoying static electricity. It costs more but it's worth it.

Buying a pro unit will still be cheaper than buying a Chinese laser.