Laser like rock melting

projectinspo

#1

When I was a kid I took a 12" by 12" Freznel lens and melted the surface of several stones. The pic is of one I was comissioned to make. Not a laser but a very high concentration of light, around 2000 F on good stones. The rock would melt into bubbling black glass.


#2

Cool i just aquired a large fresnel lense i didnt know i could do stuff like this with it. The melted sections looks like the rock @dan put in the glowforge Whatever happened with the engraved rock?


#3

Thanks! That is what reminded me of my work was the rock that @dan did. Please wear high brightness eye protection! I also once in an instant cooked a point on my finger one time to well done :smiley: You will find that rocks range from working well to not working at all to flaking off after you have worked on it for an hour! :-/ I also found that it melted glass dust into little balls. It will also melt bricks and concrete.


#4

Wow, this opens a whole new range of ideas. Again, this is creative overload. I should have ordered 5 Pros to handle all the ideas.


#5

As a senior in HS my boss’s dad wanted me to go the University of Minnesota where we was a mechanical engineering professor. Part of the informal tour was to show me a solar collector about six feet in diameter made up of hundreds of individual mirrors all focused on a single point. At that point was an inch thick piece of plate steel with a golf ball size hole melted in it. I didn’t get to see it in action, but that plate of steel made an impression. The kerf was a bit larger than your typical laser cutter, but for those who want to cut metal…


#6

Out of curiosity, gernreich, were you living in a particularly sunny part of the world when you did this project? I am guessing that this wasn’t done in Ottawa in February…


#7

Good point when picking eye protection. It’s not just about the laser, but also about what is being burned.


#8

Is this sand stone?


#9

@hroger1030 , I did most of the work in southern Arizona on VERY clear days. I found however that I was able to do the same work at the US/Canada border if the day was VERY clear.

@soldiercoleman I would call it “lava rock” that has bleached over a very long time in the desert.


#10

Now THAT is power concentration!!!


#11

I’m in the Southwest. I bet petrified wood could give an amazing look also!


#12

Holy smokes!


#13

What I had to do was test each type of stone I could get a hold of and see if it worked. I don’t think I ever tried petrified wood because at the time I did not have any, since then I found plenty of other stones that worked so I never have tried it.


#14

I picked up smooth stones along the lake bed today after seeing this posting. They are not very large, but big enough to place a design. I am in Missouri so I am assuming it is limestone. Very light but smooth, probably from the water. Has anyone had any experience working with limestone?


#15

The stones that worked for me were silicates. Ones that melted into glass in other words. I have not worked with limestone.