glass and plate engraving

[stan kern]

http://www.youtube.com/watch?v=dDwON-IwybY basswood plate engrave

http://www.youtube.com/watch?v=LVLxKV_ThVY sailboat and grape engrave on glass

[Michael Oswald]

They look great, nice work

[Ross Moshinsky]

How does the glass actually look? Lasering glass always looks good from a distance. Up close, not so much. Some people use wet newspaper to laser glass to minimize chipping. I wouldn't bother spending too much time on lasering glass. It's not where the laser shines.

Otherwise, I'm pretty impressed with how that Chinese laser is working for you. I'm curious how accurate it is. I would love to see if you draw some squares at particular coordinates, and see how accurately it places them on your material. It would be great to see one of these machines fully tested and shown they are precise. Engraving where you don't care where it hits on the material is one thing, but when you need to hit a certain spot is a whole other game.

[stan kern]

You have brought up a bunch of interesting thoughts and questions.
I found the glass ok not too rough but i can try a wet newspaper,i was wondering why some people use that.
Where does the laser shine ,cannot be cutting or engraving wood ?
I can run some tests ,i think it places cuts/engraves where i have drawn or designed,but i will test it out.
Are you saying to take say a 12inx12in piece and engrave 1 inch squares in each corner say 1/8 away from the 12x12 so there would be 1x1 squares 4 of them on the 12x12 piece?
I like the machine ,i feel its working good (i have a cnc 4 axis router) the steppers are ok and the bearings are good,not real keen on belt drives but most are like that.
What did impressed me today was i had to focus on the higher part of the plate and cut at the lower part ,you really can't notice i thought it would not engrave properly,i gues a person could remove the focus gizmo just before the job(after it focuses)

[Julie Nickerson]

These look good. That plate just a basic white plate?

[stan kern]

the plate was a 1/4 thick basswood plate turned on the lathe

[Ross Moshinsky]

The paper towel or newspaper helps reduce chipping on the glass. It's less intensity on the glass which helps it from not shattering as badly when the laser hits.

As for the test, you're a handy guy who knows how to machine. I'm just interested if you draw a 1.5x1.5 box 2" in and 2" down, will it hit the mark or be off. Sometimes the real test isn't very close to the edge, but at the extremes. I'm tempted this summer to take a drive out to Logimation and see the products run. Montreal to NJ is only a 2-3 day ship and they are in the same time zone. I'd prefer someone closer that could come in if need be, but they seem to know what they are talking about vs other people who just receive and ship. I know one thing, I won't buy directly from China. I did that once with a welder and after I got it, the foot pedal didn't work. They wouldn't fix it or even send me a new one. I was talking to them about selling their units as they were getting popular at the time, and they wouldn't even offer service to a future distributor. After that, I'll pay extra and deal with the middle man.

[Dan Hintz]

I (and others) have found the wet newspaper, dish soap, etc. to be red herrings that have little to no effect on the quality of the engraving... if you are engraving properly. Blasting glass with a ton of power and 100% coverage is a sure-fire way to create a rough engraving and horrible detail.

My last project was a number of Riedel goblets (conclusively proving for the first time, I might add, that etching leaded glass is possible), and the etching is baby's bottom smooth with fine detail. It does not look the same as sand blasting, but that's a fight for another day.

[Ross Moshinsky]

I (and others) have found the wet newspaper, dish soap, etc. to be red herrings that have little to no effect on the quality of the engraving... if you are engraving properly. Blasting glass with a ton of power and 100% coverage is a sure-fire way to create a rough engraving and horrible detail.

My last project was a number of Riedel goblets (conclusively proving for the first time, I might add, that etching leaded glass is possible), and the etching is baby's bottom smooth with fine detail. It does not look the same as sand blasting, but that's a fight for another day.

Would you mind posting your speed, power, and resolution settings?

I just got a sandblast setup, so I'm not really concerned, but I always like to learn. I've seen some passable laser engraved glass, but when I pick up a piece sand blasted, it's enough where I basically refuse to do glass on the laser.

[stan kern]

http://www.youtube.com/watch?v=vI5n53ZB3-I

I used a 12.5x10.5 plywood piece engraved a 10x11 square and then a square in each corner
I found the machine to be fairly accurate,not perfect but i think i know where i need to make some adjustments but its nothing to do with the chinese make its because when i used the indexer and the machine reset and returned to home position the head went through my work piece and i think i knocked it off centre a bit.
I feel i can adjust that

[Ross Moshinsky]

Cool test. I'd be interested in seeing the lines less thick to really show off how precise it is. Another quick question, is there a reason why the plate is off? Just placement on the table?

Either way, I see these machines have a lot of potential. Maybe in July I'll take a ride up to Montreal to see things in action. That time is the slowest for us and it would be good just to know how well these machines work.

[stan kern]

http://www.youtube.com/watch?v=ZhBQT6OfsV4
adding a border graphics to the plate

http://www.youtube.com/watch?v=LAKpD3Xr4HM

graphic detail to a small piece
The plate is off because of the head being out a bit ,this is where i first noticed my problem ,i'm out by 1/16in on a 3in dia circle.
I am going to take it apart tomorow and re-align the head perpendicular to the table .
It was your request for a test that brought this miss alignment out in the open for me ,the plate caught my eye but i kept making excuses

[David Fairfield]

Wet newspaper makes a big difference in the quality of my glass engraving. Makes the surface more frosted, and therefore provides more contrast with the unengraved glass and a better finished product.

Dave

[Ross Moshinsky]

Stan,

Why are you engraving in the middle of your table vs the top left? Setup a guide along the top and left with a nice ruler. Then set your zero and you'll never have to think about where the piece has to sit again.

[stan kern]

Yes i can do that ,but my trouble was when i had the indexer on the table (right lower corner towards the opening hatch) and when i finished i shut down the machine the head was over towards the left a bit and the next day when i switched it on the head took off to home position back right corner ,going diagonally across the table and i had a 3inch cylinder sitting on the indexer wheels and the focus gizmo caught.
I felt terrible ,got everyhting back but i wonder if i'm a bit off when i put everyhting back