Lasering a mirror

[matthew knott]

Been asked to laser a wedding plan on a mirror, how would you guys do this, engrave from the front or back? any tips??
Cheers!!!
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[Robert Silvers]

Go to Lowes or Home Depot and but a $10 pack of 12x12 mirrors. Try it both ways. It takes trials to get the power just right so you will need cheap mirrors.

[Darryl Hazen]

I would engrave from the back then paint it with the color font they would like. You can laser it either way. Doing the back gives you a few more options.

[Martin Boekers]

Some (more expensive mirrors) are "mirrored" to a copper plate. Cheap mirrors engrave nicely from the back. Post a photo when your finished!

[Kev Williams]

I just went thru a not-so-fun mirror escapade. 22 mirrors for family gifts, just off-the-shelf things from some store. I found that about half of them my 40w LS900 wouldn't penetrate the mirrored backing, whatever it was. However, the same mirrors in the same place lasered like gangbusters in my 25w Universal...? It had NO problem with the coatings. On a similar vein, my 25w laser refuses to make a nice white mark on black anodized aluminum, no matter how fast, slow, power settings, it doesn't matter. I light gray is all it'll get. The 40w makes much whiter marks on anodized.

What's up with that? (and sorry for the slight hijack)

[Robert Silvers]

Pulse frequency maybe.

[Mike Chance in Iowa]

I have had better luck engraving on cheap mirrors. Some of the more expensive ones had a thicker backing and one batch had a grid-like pattern in the backing that was really difficult to engrave thru. I never took pictures, but I had some nice results engraving on the back and painting with different colors such as copper metallic, gold metallic. I engraved a name on the back of one little mirror and painted the back a hot pink for a friend's teenage daughter's locker. She loved it - her name showed up in hot pink thru the mirror.

[john swank]

I use the mirrors from Lowes all the time. Make sure you get the ones without any adhesive on the back. Engrave from the back.

[Dan Hintz]

I would engrave from the back then paint it with the color font they would like. You can laser it either way. Doing the back gives you a few more options.

This is always my vote... from the back. It looks cleaner since there's no multiple reflections of the text to make it look blurry.

[Tim Bateson]

I can't think of a single reason I would engrave a mirror from the front, although there are probably a few. That's just my opinion of which you'll find many here. So follow the earlier advice and buy the cheap mirrors and do some testing.

[Dave Sheldrake]

First or second surface mirrors Matt?

cheers

Dave

[Kev Williams]

I can't think of a single reason I would engrave a mirror from the front, although there are probably a few. That's just my opinion of which you'll find many here. So follow the earlier advice and buy the cheap mirrors and do some testing. I engraved the 3 Disney hitchhiking ghosts onto the front of three 12x18" mirrors for a lady for Halloween-- The second 'ghost' image reflecting from surface of the glass is actually really cool when you walk by the mirrors-

[Keith Outten]

I always engrave mirror from the back.
I also keep in stock both silver and gold acrylic mirror for several reasons. Acrylic mirror is lighter in weight and since you can vector cut acrylic there are more options available.
.

[Dave Sheldrake]

I always engrave mirror from the back.
I also keep in stock both silver and gold acrylic mirror for several reasons. Acrylic mirror is lighter in weight and since you can vector cut acrylic there are more options available.
.

Tougher as well from memory isn't it Keith?

cheers

Dave

[matthew knott]

Thanks guys, back it is then !!! not something i would normally do but its a 'favour' no doubt it will all go wrong as 'no good dead goes unpunished'

[Joe Hillmann]

Small text (say under one inch tall) is very hard to read if you engrave from the front. You see the engraving as well as the reflection of the engraving and it becomes blurry.

[john passek]

Are there any precautions to take if engraving the front, like masking. can the beam be redirected causing risk to eyes. I have always engraved the back, much nicer results, for me anyways.

[Dan Hintz]

Are there any precautions to take if engraving the front, like masking. can the beam be redirected causing risk to eyes. I have always engraved the back, much nicer results, for me anyways.

CO2 wavelengths can't make it through the glass to be reflected, so you're safe.

[Keith Outten]

Tougher as well from memory isn't it Keith?

cheers

Dave

Dave,

Yeah, acrylic mirror is more forgiving then glass mirror but the down side is that it will scratch if abused and glass won't. I can't say that I use the two for the same purposes but acrylic gives me another substrate to use for less common types of projects. I use gold acrylic mirror on top of black acrylic mounted on a wooden plaque a lot. The look can be quite elegant on some signs and its cheap and fast to produce.
.

[Jiten Patel]

Send it to me Matt - wedding is what we do - no need to bother yourself with such menial tasks!!!

From the back works best!

Also be careful when using acrylic mirror - warp on larger sheets can create a hall of mirrors effect.

[matthew knott]

I may very well send her to you Jit, she's the wife of a guy we do work for and she does a side line in wedding bits and pieces so i said i would help her out, i will mention your sexy stationary when she comes in.

[Patrick Licata]

Hello,
Bringing up an old post here. What kind of settings do you recommend for engraving the backs of mirrors. I know it will depend on the coating etc., but what starting point would you suggest? I have a 35 watt Epilog and I know they recommend 30s 100pwr for 400dpi for plain glass.
Thanks,
Patrick

[Jerome Stanek]

Thanks guys, back it is then !!! not something i would normally do but its a 'favour' no doubt it will all go wrong as 'no good dead goes unpunished'

Just remember to mirror your engraving

[Jess Phiz]

We engrave the front, just masked up then finish with some Rub 'n' Buff as we do on all glassware, the finished product turns out well
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[Bryan Jater]

If you use fiberlaser it works well from the front

[Tim Bateson]

Hello,
Bringing up an old post here. What kind of settings do you recommend for engraving the backs of mirrors. I know it will depend on the coating etc., but what starting point would you suggest? I have a 35 watt Epilog and I know they recommend 30s 100pwr for 400dpi for plain glass.
Thanks,
Patrick

Too little power and the coating or some of it will remain - run again. Too much power (with-in reason) and you engrave the back of the mirror - probably what you want. So, unless you are applying so much power as to break the mirror, test away. I would note however, if you start with low power & need to run again - please INSURE the piece is secure and cannot move between runs.

[Bert Kemp]

Don't think anyone mentioned that if you do decide to engrave the front DO NOT! run your fingers or hands over the engraved area unless you want a hand full of glass slivers.:eek:ouch! On the rare occasion I engrave the front I always take it to the sink and use the sprayer to rinse off the piece first before rub and buff;)

[Mitchell Tutty]

If you tweak the settings just right, you can engrave just the backing off, and not etch the glass at all.

It has an incredibly cool subtle effect.
Depending on what the mirror is reflecting, it looks different at all angles.
It may reflect a dark wall, and be incredibly contrasting, or as you walk past it reflect a white wall, where you can't notice it at all.

I engraved an entire shop front in mirror tiles, as you approach it is hardly visible and definitely not noticeable. But as you're just about to drive past it's incredibly contrasting and catches your eye.
Will see if I can dig up a few photo's.

Mitchell

[Jerome Stanek]

I have done the back and then spray painted it to give it some different effects

[Bill Cunningham]

I've done lots of photographs on mirror, and always engrave and colour from the back301777

[Bert Kemp]

Show off LOL beautiful Bill wish I could do that.

I've done lots of photographs on mirror, and always engrave and colour from the back301777

[Mike Audleman]

I can't think of a single reason I would engrave a mirror from the front, although there are probably a few. That's just my opinion of which you'll find many here. So follow the earlier advice and buy the cheap mirrors and do some testing.

I can think of a few. First, you can frost the glass to form decorative accents on corners and edges. This provides a 3 dimensional look to the accents where the rear engraving would be very flat looking. Second, is wanting to light the effect. You can edge light the glass (mirror) that has been front engraved so that the "frosted" sections will light up. To get the same effect by rear engraving, you would have to engrave through the mirror coating as well as into the rear glass surface or engrave through the mirror coating and then apply an LGA behind the mirror.

But for this apparent project, i agree with the double reflections issue of front etching.




First or second surface mirrors Matt?

cheers

Dave

I would be surprised to find a front surface mirror used in a project like this.

[Charlie Hawkins]

I was given a bunch of mirrors out of projection TV's, and the fellow said I may be able to use them for engraving wth my Epilog Summit. They are double-sided mirrors, however, and have no 'coating' like one-sided mirrors do. I did try a smaller one that fit in my engraver, and it did a glass-type etching on the mirror glass... however, the other side didn't engrave at ALL! Are these a special type of mirror, and has anyone ever used these for engraving? I am not sure what you all use to mask the mirrors, either. The side that did engrave, had small 'shards' of glass left on the surface (very small particles), and is this normal also? I am in need of knowledge on this, as I am not sure about these mirrors. I have had a lot of fun engraving granite tiles so far, and am enjoying my EPILOG Summit very much!! Thanks!
Charlie

[Bert Kemp]

Charlie I have no idea what type of mirrors these are but the side your engraving leaving the shards is normal, you can cut your power down some to reduce this, but you are fracturing the surface and it results in tiny pieces of glass.




I was given a bunch of mirrors out of projection TV's, and the fellow said I may be able to use them for engraving wth my Epilog Summit. They are double-sided mirrors, however, and have no 'coating' like one-sided mirrors do. I did try a smaller one that fit in my engraver, and it did a glass-type etching on the mirror glass... however, the other side didn't engrave at ALL! Are these a special type of mirror, and has anyone ever used these for engraving? I am not sure what you all use to mask the mirrors, either. The side that did engrave, had small 'shards' of glass left on the surface (very small particles), and is this normal also? I am in need of knowledge on this, as I am not sure about these mirrors. I have had a lot of fun engraving granite tiles so far, and am enjoying my EPILOG Summit very much!! Thanks!
Charlie

[Nancy Laird]

Hi, all. Just getting back into SMC and reading up on past laser questions. As far as engraving glass is concerned, if you are engraving flat, from front or back, make sure your piece is stable, and ENGRAVE IT TWICE. As soon as the first pass is finished, just press the button to do it again. The second pass removes most of the glass bits and removes those bits that didn't get knocked out the first time. We do glass for flag boxes and always engrave in reverse, and running it twice makes it look like it has been sand-blasted. Just our experience.

[Mike Audleman]

They sound like first surface mirrors. This is common in projection systems. The side you engraved is actually the back of the mirror. Its the side with the glass. The other side is what the TV used not the side you etched. The reason your laser didn't touch the second side is, well, its a mirror! The light bounced off as it should have. I don't know any way other than applying some sort of material to it to etch on that side. Tape, masking spray, anything that will absorb the IR from the laser.

The reason for this style of mirror in a projection system is so that the image is not doubled. A standard second surface mirror (typical bathroom mirror) actually casts two reflections! Take a standard bathroom mirror and lay it flat on a counter. Set a pill bottle or other upright object on top. Now get down at an angle (45 or so) and look at the base of the object and its reflection. You will see two reflections! One is coming from the silvered surface on the back of the glass. The other is coming from the front surface of the glass. The thicker the mirror glass, the more obvious this second image will be and the farther it will be separated from the main reflection. This is why typical mirrors are made from the thinnest glass possible, it reduces the offset of the second reflection.

Now take one of your projection mirrors. Set it on the counter and put another pill bottle on it and look at it from the same angle. You will see only one reflection. That is because the silvering (aluminum usually) is on the TOP of the glass, not the back. Since light does not pass through the glass to get to the silvering, there is no second reflection. If you see two reflections like the bathroom mirror, you are looking at the BACK of the projection mirror, not the front!

Here is a photo I took with objects sitting on top of a standard second surface mirror.
http://cdn.ipernity.com/200/74/00/36677400.7c97ea4b.1024.jpg (http://www.ipernity.com/doc/wolfie/36677400)
Look in the lower left at the reflection. Notice there is a second fainter reflection offset from the brighter first. That is because the glass and the silver both reflected the light.

[Charlie Hawkins]

Hey thanks for the tip on engraving twice to get rid of the shards1 And, the first surface mirrors is something I had not heard of before, but it makes sense. I am at a loss as to how i could get good results from these mirrors, as I have seen on here. I don't know if there is any way to engrave through that surface, as it is metal of some kind, I believe...