G-Code for a lens

[PEU]

I want to test my machine in 3D milling, and I tough that a acrylic lens could be a nice way to do it.

So anyone here have a G-Code file for an acrilic lens?

I have some 2x3x0.5in pieces of acrylic and many 1/8" ballnose mills to test

THANKS in advance


Pablo

[joecnc2006]

Originally Posted by peu I want to test my machine in 3D milling, and I tough that a acrylic lens could be a nice way to do it. So anyone here have a G-Code file for an acrilic lens? I have some 2x3x0.5in pieces of acrylic and many 1/8" ballnose mills to test THANKS in advance Pablo

I would use a ray trace program and design the lens for the size and focal length you need, this will give you the curve you need, concave or positive min. lens, then draw it into cadd and create the g-code from there.

Joe

[PEU]

Joe: I don't have any special requierements for the lens, I had in mind these lenses used for reading maps that are flat in the base and curved on top.

I just want to test the router

Thanks!


Pablo

[Chris Welton]

The GCode file would be huge unless you can tell us for a fact what kind of circular interpolation your controller uses....

[Lionclaw]

I threw together a quick VB program to output code for a lens.

Double check the gcode before running it. Let me know if you find any bugs. I know next to nothing about lenses, so hopefully I'm doing this right.

Source is included.

PLEASE!!! Post pictures of your results. I don't have any thick polycarbonate to test this on. So far I've only tested on MDF.

http://www.comptonsoft.com/LensCrafter_001.zip

[joecnc2006]

Originally Posted by Lionclaw I threw together a quick VB program to output code for a lens. Double check the gcode before running it. Let me know if you find any bugs. I know next to nothing about lenses, so hopefully I'm doing this right. Source is included. PLEASE!!! Post pictures of your results. I don't have any thick polycarbonate to test this on. So far I've only tested on MDF. http://www.comptonsoft.com/LensCrafter_001.zip

Very nice program, now all you have to do is make a lends for your projector... lol

What bit did you use ?


Joe

[Lionclaw]

Exactly Joe That's my motivation here. A homemade pro lens Now if only I knew more about optics I'd be well on my way...

I'm thinking about disassembling my current triplet lens and trying to reproduce it just to see how well it would work.

I'm testing with a 1/4" ballnose right now. I've got a 1/8" ballnose I'll try later.

I'll post a pic with my MDF results here in as soon as the machine finishes the current run.

[joecnc2006]

Originally Posted by Lionclaw Exactly Joe That's my motivation here. A homemade pro lens Now if only I knew more about optics I'd be well on my way... I'm thinking about disassembling my current triplet lens and trying to reproduce it just to see how well it would work. I'm testing with a 1/4" ballnose right now. I've got a 1/8" ballnose I'll try later. I'll post a pic with my MDF results here in as soon as the machine finishes the current run.

Cruser measured the existing pro lens if you need the measurements i can get them for you and also make a raytrace for it and see about tweeking it, also rox has the info, we kinda worked the lens out preliminary in chat and he finished it.

[Lionclaw]

I'll have to get myself a book on optics. If this works out ok, I think I'll try to start off by making a larger version of the 330mm standard triplet. I think there'd even be a pretty good market for it. A lot of light is lost with the current 80mm diameter.

[Lionclaw]

Here's a picture. The one on the left was done with .1" stepping. The right with .01" stepping.

[Chris Welton]

Polishing it will be the hard part, i'd think... The smaller your scallop heights, the more scallops you will have.

[Lionclaw]

Geof made a post where he described how to polish acrylic. I can just mount the lens on the lathe and work away at it.

http://www.cnczone.com/forums/showpo...83&postcount=9

Now I just have to hurry up and get the lathe fixed :frown: