Newbie- engraving mirrors

[MonoNeuron]

Hey all.
The laser burns away the backing of the mirror which also helps burn away the silver reflective coating which is very thin. I have to use all my 30 watts and engrave at 3 inches per second for it to work properly. Don't forget to reverse the picture image so it comes out properly looking from the front.

I use just plain old steel wool to clean up the back surface of glass debris and chips and wipe off with a clean cloth then paint. If you want to get creative then you can use different colours for different parts but I don't have the time to muck about with all that so they just get a coat of good quality matte black enamel paint.

You also have to disassemble the mirror from it's frame or just remove the backing material to expose the back of the mirror surface and engrave directly onto that surface.
Don't worry if you think you are asking a stupid question as we have all been down that road before and the only stupid question is the one you DON'T ask.
It's all a learning process but an interesting one.

here are some examples. ( I have posted them on your other thread too.)

[denbruno_09]

mono, thanks for the clear explication. Do you do engraving for business of for hobby? if for business, how do you set pricing to engrave a mirror with a picture of a client, so no standard piece, but something with some work on.
thanks

[MonoNeuron]

We engrave for the business but really don't sell too many. We have people interested in them all the time but there isn't too much money flying around here so people don't buy them very often. We have done a couple of orders for pictures of loved ones and sell them at $49.95 but we don't have much expense with the business so we sell them cheap. Some businesses in the USA sell them for $99.00 for a 1 foot square mirror tile. Our main sale for the laser is with Scrapbooking letters and names in Chipboard.
We use Photograv and Corel draw V X3

[KisKZ]

Hello!

A very good, absolutely free etching software (DotG) released now in Englis language!

If you want, test it!



You can find info here:

HobbyCnCArt news

Have a nice day!!

[TLHarrell]

Mono- Those mirror tiles look great. I've been doing the same, but with very mixed results. And mirror backing smells absolutely awful! Combination of burning off the grey coating and the burning metal smell... it's the worst!

For others who are starting on this and are confused by the material, it is basically just a sheet of ordinary glass with a coating on the back. When you burn through it completely, it is clear. For doing logos and lettering, it is fantastic. For images, I've had a tough time with getting the contrast right. What looks great on screen doesn't always register on the material.

[KisKZ]

We made some 1W diode laser set for a small group on www.hobbycncart.com.

Before tests I think this power not so mutch.
But...
Then I tried this on mirror and result is very impressive.
I'm made this with feedrate 100mm/min, with an 1W 808nm laser diode:

http://hobbycncart.com/_ph/16/2/116390915.jpg

[vincenttor]

Well i have been messing around with mirrors again,
Have ruined allot of mirrors again

And still i do not get it how they become ugly when i paint them black.
Here are some results of the mirrors i made

i have no idea how much inch/per the speed is because its in percentage in my software ( retina engrave FSE)

put it on 8 % speed ( pretty slow)
14mA Almost max power

and here are the results. i am just not satisfied because if i look to the results mononeuron has those are great

Have cleaned them with steelwhool , real good tip indeed before painting.

This i painted white, was a test with halftone effect and it came out pretty good with less details.

made a mistake and the laser stopped hehe yo can see that why the txt is there



looks pretty good if the back has light shining on it.




few layers of black paint



http://www.mijnalbum.nl/GroteFoto-VOPAW3LJ.jpg
bigger pic, sorry its upsidedown

you see its not so nice anymore.

here is a better pic


as you can see it allmost is not visible anymore and looks not real nice

Really have no idea what to do about it, maybe testing on some other mirrors is the next step

[keebler303]

I think you need to invert your image before laser engraving. On mono's samples, the lighter parts are not engraved and the darker parts are. Yours is the reverse.

Matt

[osphoto]

This is a rather cool thread. I've got 40W laser that I purchased for making gaskets.

Didn't realize I could etch glass with it. Very cool!

[vincenttor]

thanks for your reply keebler,

but on this picture the color is indeed reversed


But on the next one i think its not if you look to the text and the image


Thats why i havent got a clue why its not turning out as nice as these examples

[MonoNeuron]

They do look as if they need to be the negative of how you are engraving them. The Johnny Depp one especially. What have you got to lose except another mirror. I use the ones from Ikea as well and they are a pretty good quality mirror. I would just make the engraving about 3" square or 75mm square just to try it and that shouldn't use up too much mirror. It is hard to get right but in the end it is all worth it.
I explained to one lady who has bought a lot of mirrors from us that it can take up to and hour to clean the picture up and get it right and then another 3 hours to engrave it and she said "it's only 3 hours" !!!
Some people have no idea how complicated things are and how much time is involved just getting to the stage of being able to sell a product that is good enough for a customer and potentially something that will last 100 years or more. (If the paint stays on :-) )
I engrave at 3" sec and 30 watts of power. Just to get an idea of how fast it is just set a ruler on the table and count 1,2,3,4 and see if it had gone 12". I had to engrave at the full power of my 30 watt tube to get a good result and sometimes a different mirror needed to be slowed down to 2.8" sec to work properly.
If you engrave too slowly then you refuse the silica on the back of the mirror causing a sort of scab to form that needs to be scraped off. Don't go too slow or use too much power causing this to happen.
The laser needs to be very focused and on mine I need to engrave at 320 lines per inch for the lines to blend into the next one. I process at 340dpi.
Rich.

[MonoNeuron]

The Marilyn picture isn't reversed!. Look at the faces of the people in the mirrors and you will see they are all white or mirror. the Marilyn picture has a dark background that is probably throwing your perception out.
All the engravings are positives but reversed side to side so it comes out the right way when it is turned around.
If you engrave on Black Granite then you need to reverse that picture ( Negative) because the granite is black and that acts as the shadow detail in the picture.
Rich.