Difference between revisions of "FieldStops"

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==OpenSCAD==
 
==OpenSCAD==
  
OpenSCAD is a dream. I wrote the following script which even includes kerf compensation. It auto generates and even neatly tiles the two pattern sets. Then I can export right to DXF. This is my first openSCAD project. I think I am hooked...  
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[http://www.openscad.org/ OpenSCAD] is a dream. I wrote the following script which even includes kerf compensation. It auto generates and even neatly tiles the two pattern sets. Then I can export right to DXF. This is my first openSCAD project. I think I am hooked...  
  
==Results==
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==Script Results==
I still need to actually laser these out of black cardstock the next time I am at the lab but...
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There is a kerf bug. Technically the kerf is the entire width of a cut, not the difference between expected and actual edge coordinates. The script is actually looking for 1/2 of the kerf. So if your cut is 0.3mm wide then you need to put in 0.15mm as your kerf. Oops. I'll fix that someday.  
  
 
Here is the openSCAD script. [http://svn.nebarnix.com/sub/CAD/laser/microscope_stops.scad]
 
Here is the openSCAD script. [http://svn.nebarnix.com/sub/CAD/laser/microscope_stops.scad]
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And here is a CorelDraw render of the DXF [[Image:Microscope_stops_0kerf15mm.png|640px]]
 
And here is a CorelDraw render of the DXF [[Image:Microscope_stops_0kerf15mm.png|640px]]
  
And here is a pdf file you can use to laser your own set but really you should just load the openSCAD script and customize it yourself! CMON LAZY BONES! [[Microscope_stops_0kerf15mm.pdf]]
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And here is a pdf file you can use to laser your own set but really you should just load the openSCAD script and customize it yourself! CMON LAZY BONES! [[image:Microscope_stops_0kerf15mm.pdf]]
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==Laser Results==
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Using 1mm thick cardstock at a power of 20 Watts and a travel speed of 10mm/sec I was able to produce the following. I assumed the same 0.15mm halfkerf. The results are amazing! The spars and ring are thick and sturdy and they fit perfectly in my filter tray!
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<flickr>8555579059|thumb|left|m|All Stacked Up.</flickr><flickr>8566698700|none|thumb|m|Second run with engraved identification.</flickr>

Latest revision as of 14:01, 22 March 2013

Problem Statement

I want darkfield and oblique stops with my low and medium magnification objective lenses on my compound microscope. I want them to be repeatable in case they break or I find another needy scope. I want them easy to make and use so I can share them with the world. They need to fit in the filter tray. I also don't really know what sizes I need so I want a way to generate a laser cuttable geometry that can sweep a variable over whatever range.

Solidworks

First I made a few patterns in solidworks but I wanted to be able to change things like arm spar geometry and swept range really fast and painlessly. That is not solidworks. I wanted to change one thing and have it carry through the entire swept set. And kerf compensation because the laser at HSL doesn't automatically apply it. Yikes... Onward towards a better solution...

OpenSCAD

OpenSCAD is a dream. I wrote the following script which even includes kerf compensation. It auto generates and even neatly tiles the two pattern sets. Then I can export right to DXF. This is my first openSCAD project. I think I am hooked...

Script Results

There is a kerf bug. Technically the kerf is the entire width of a cut, not the difference between expected and actual edge coordinates. The script is actually looking for 1/2 of the kerf. So if your cut is 0.3mm wide then you need to put in 0.15mm as your kerf. Oops. I'll fix that someday.

Here is the openSCAD script. [1]

And here is what it spits out (DXF) [2]

And here is a render of what it spits out (PNG) Microscope stops.png

And here is a CorelDraw render of the DXF Microscope stops 0kerf15mm.png

And here is a pdf file you can use to laser your own set but really you should just load the openSCAD script and customize it yourself! CMON LAZY BONES! File:Microscope stops 0kerf15mm.pdf

Laser Results

Using 1mm thick cardstock at a power of 20 Watts and a travel speed of 10mm/sec I was able to produce the following. I assumed the same 0.15mm halfkerf. The results are amazing! The spars and ring are thick and sturdy and they fit perfectly in my filter tray!

DSC_3900.JPG
All Stacked Up.
Microscope Stops
Second run with engraved identification.