The main problem existed in the baffles (which are heart of a FTIR table). In the pages below I show how I used hobby wood (cheap hobby wood) from Home Depot, and I drilled holes into that by hand. The consistent 1 inch spacing I had intended had drifted throwing off my even spacing. In addition I couldn't get the dremel and my hand to drill a centered hole so the IRLED's couldn't sit in the middle of the baffle and that threw the alignment of the IRLED's with the acrylic off.
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To the left is the drill press I used at STARBOT. Isn't she a beauty?! You can't see it but to the right is a digital readout that goes to 0.0001 inches! Even with this beauty I still couldn't drill a straight line of holes down that wooden baffle! I was seriously starting to doubt my abilities at this point. Until my friends at STARBOT told me that the grain of the wood was pulling on the drilling chuck. I could do two things, start over with the wood, drilling tiny pilot holes to counter the grain pull effect, or I could bypass it altogether by using Ultra-High Molecular Weight Polyethylene UHWP. I went to Mc-Master Carr and found exactly the part I needed at the measurements I needed; Link to McMaster Carr Baffle Part. I bought two for a total of 10 feet. I then cut each into a 24 inch and a 36 inch part. This would form the frame for my FTIR.
Then all I had to do was drill, and drill, and drill some more.During the MK I proof of concept I only drilled LED's into the top and bottom of the frame. This did a good job of delivering light to the screen, the IRLED's I chose were good enough to deliver light to the entire surface with only half the frame lit up. This time, however, I want to take advantage of the entire frame and string it up with IRLED's. This means a lot more drilling. I drilled holes 1" apart from each center. Giving me 23 holes on the 24" side and 35 holes on the 36" part.
Currently, I need to reorder a new acrylic screen (the old one got really scratched up), and a lot more IRLED's to finish wiring up the new baffle. That's where I'm currently at. Just waiting for the new parts to come in to finish the wiring and begin the coding section of the project.
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In the mean time I realized I never posted up pictures of how I modded my webcam to be more sensitive to IR light. That's coming up next.
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