1/4" Custom Corian for Engraving

[Ryan O'Hara]

Creekers, I am in need of a custom corian "slab" to which I can mount a stainless sheet to. I am engraving kapton stencils and have found that the vector grid is not flat enough to mount the stainless sheet that came stock with my epilog laser. Is there anybody here with a router that I could send a dxf file to? Thanks for all your help.

[Dave Johnson29]

Hi Ryan,

I do not quite understand what you want made or done. A DXF of what?

[Scott Shepherd]

Talk to Keith Outten about it. I don't know anyone that has as much corian as he does.

[Ryan O'Hara]

Dave, I am basically looking for a custom corian design. I have a dxf of what I need routed or cut with a laser. I just don't have the resources to do it here and would prefer to give some business to someone here on the Creek if possible.

Scott, I will contact dave via PM. Thanks!

[Scott Shepherd]

Scott, I will contact dave via PM. Thanks!



Or Keith ;)

[Kenneth Hertzog]

Ryan
I do a lot of dxf cutting
if you want I will look at the file
if not to big ( larger than 24 x 30
I can do that job for you
if you want send file and I will have a look
ken

[David Harvey]

Ryan,
If you'll send me the file I'd be happy to take a look at it. I can CNC route for you, and if need be I can supply the Corian as well.

[Ryan O'Hara]

Folks, these are the design files:

The general size is 18.25" x 24.313" with a grid of .1875" holes.

1/4"-3/8"-1/2" are the preferred thicknesses. Let me know what you have in stock and I can work with that.

X3 and DXF Format (www.ohararp.com/files/STENCIL_SHEET.zip)

[Jerome Stanek]

I am from up around Cleveland and have a couple 4 X 8 shopbots.
I will have to check what corian I have and see if I can open your X3 file. The dxf only will open as a text file. I can not download it.

[Ryan O'Hara]

Jerome, I changed the link to a .zip file. You should be able to grab that no problem now.

[David Harvey]

Ryan,
I tried to reply to your PM, but your settings don't allow you to receive private msgs.

[Ryan O'Hara]

PM enabled (I figured this would on by by default). Sorry bout that. More than likely user error on getting that setup properly.

[James Jaragosky]

PM enabled (I figured this would on by by default). Sorry bout that. More than likely user error on getting that setup properly.
This looks like a good job for a CnC router.
What color Corian is needed for the job?
Corian is heavy to ship, I suggest you find a local CnC owner to help out.
I would post for help at the ShopBot forum.

[Richard Rumancik]

. . . I am engraving kapton stencils and have found that the vector grid is not flat enough . . .

I realize your request was to find someone to make a Corian slab - seems like you have a few leads . . .

But do you mind elaborating on the "engraving" of Kapton stencils? Are you making solder paste stencils or what? Are you using raster images to cut the openings in the Kapton?

I tried Kapton many years ago and did not have much success - I came to the conclusion that I would need a 9.2 micron laser instead of a 10.6 to do this well.

[Dan Hintz]

I tried Kapton many years ago and did not have much success - I came to the conclusion that I would need a 9.2 micron laser instead of a 10.6 to do this well.
How did you come to that conclusion? The difference in wavelength is so minor as to have little effect on the ability of it to cut the material, nor for it to have any appreciable effect on the accuracy. Was there another factor coming into play with your situation?

[Ryan O'Hara]

I engrave the stencils for solder paste for use on electronic parts. The kapton is ~.0035" thick and I raster engrave it with my 45W laser. I do use a 1.5" lens for fine detail work at 600 dpi. Overall it works very well.

The trouble I was having is that the stock engraving sheet has become slightly warped. I had an 1/8" stainless sheet cut on a waterjet and I was hoping to get around this "flatness" issue, where by the change in height over my work area is significant enough to cause the laser to become out of focus and not properly cut the stencil. The 1/8" sheet has just enough bend to it that I now need this heavier and "flat" corian sheet to act as a sturdy substrate.

[Dan Hintz]

I would think a quick fix would be to add some appropriately-sized ball bearings via glue to the bottom of the 1/8" table... why go to the extra trouble of layering multiple sheets, just fix the one you have. Stick a couple of ball bearings (or other scrap shim metal) in the center to keep it from bowing.


As far as the masks go, any particular reason you're rastering? I suppose if you have a lot of small holes, rastering may be faster than vectoring. Have you tried both with this file?

[Ryan O'Hara]

Dan, I have done a lot of QA inspection stuff and really need a sturdy substrate to do this all with. I have to move the laser to the garage and temperature variations are also causing some trouble. The corian should really help out with this.

Raster is by far way faster than vector cutting. Trust me. I have been down that road using mylar. I could easily have a 1 thousand holes to cut in any given stencil.

[Richard Rumancik]

Ryan - thanks for the info. I am surprised you got good results with a conventional laser as I did not have success when I tried . . . maybe I will look at it again.


How did you come to that conclusion? The difference in wavelength is so minor as to have little effect on the ability of it to cut the material, nor for it to have any appreciable effect on the accuracy. Was there another factor coming into play with your situation?

I just made up that part about needing a 9.2 micron laser . . .

Seriously, I didn't even know 9 micron CO2 lasers existed until I read an article in a trade magazine some time later. I came to the conclusion I needed a 9 micron laser when I found out that is what the industry generally uses for Kapton. Here's one quick article I found.

www.coherent.com/Downloads/CO2ProcessingRev2.pdf (http://www.coherent.com/Downloads/CO2ProcessingRev2.pdf)

Apparently there is much better coupling with Kapton at 9.2-9.6 microns. The problems I had were excessive charring and also buckling of the film due to localized heat. It was pretty discouraging so I gave up on it.

I could buy a "drop-in" replacement for my Synrad tube from here:

http://www.synrad.com/93Series/index.html

but I don't know if there is enough market to do that.

I agree with Ryan that you need to raster. There are too many starts and stops on little rectangles .03" x .06" and smaller that it will just make a mess on the corners, never mind the processing time. I found that raster gives more time for the heat to dissipate as well.

I did not develop a full manufacturing process as Ryan has, but I found that using raster also had an advantage because if I wanted to adjust aperture size I could use PhotoPaint to add or subtract pixels all around the shapes to change the size. If you have 1000 shapes, it would not be practicable to do any size adjustments on a global basis, at least not in CorelDraw.

[Ryan O'Hara]

Richard, don't get me wrong, when you fire the laser on the kapton you generate a really fine ash as the kapton is vaporized. It will leave your machine with this fine ash and it can be pretty messy. Simple Green is your friend! The stencils require a quick washing with soap and water and quick dry with some paper towels.

[Dan Hintz]

I just made up that part about needing a 9.2 micron laser . . .
On that note...

For a long time I had assumed the usable wavelengths of lasers was best defined in terms of tenths of a micron, i.e., 10.6 is different than a 10.7, but no one would bother to distinguish between a 10.6 and a 10.61. Well, that assumption was wrong. I have a book that lists (at the time of publishing) all known laser wavelengths used in manufacturing, including their chemical composition to create that beam. A book... many hundreds of pages, 40 or so frequencies per page, listed to 6 decimal places. I T i s I N S A N E!

[Ryan O'Hara]

Just wanted to say thanks to everyone for you help on this. David Harvey ended up cutting the corian for me and did a great job quickly and for a good price!