Collin and I set up an appointment with Chelsea Graham at West Campus to try out her Artec scanner. We were told that this is the next level scanner up from the David scanner we already have and it might be the best for scanning something small like the scorpion. We took over two specimens to West Campus, a 9.5cm scorpion and an 11cm centipede. The scorpion was sprayed with white children’s poster paint first. The centipede was already a light color, so we thought we’d try it without the poster paint. It turned out that we didn’t have enough time to work on the centipede, but Chelsea was able to get a pretty good scan of the scorpion.
A pretty good scan is made up of many scans stitched together. Each scan was assessed before saved and then, if it made the grade, it was included. The scanning took several hours and some experimenting to get the scorpion in 3D. Chelsea worked further to clean up the scan file after we left and later sent us what appeared to be the best scan we have been able to get to date. Collin immediately set to work sending the scan to the Taz printer. Again, we got the best print we have been able to get to date. Both filament printers (Taz 6 and Dremel) leaves a visible contour even at a high resolution print setting, which makes the prints hard to use without sanding or covering with wax or putting them into an acetone gas chamber.
By coincidence I ran into Joe Zinter and Dante Archangeli from CEID on my lunch break. This was on the very day that Collin got a couple of prints from our filament printers. I asked Joe if he had a laser/resin printer at CEID. He said they didn’t have one, but that we should try their Objet Fused Deposition Modeling Printer. He told me the quality is as good as the laser/resin printers. Within an hour, I had the scan on a thumb drive over to CEID and they had it loaded and printing by the time I left. The scorpion print was scheduled to take 3 hours and 30 minutes, so I told him I would pick it up the next day.
I was back at CEID in the morning and the prints were done and still in the printer. Dante scraped it off the printing table and handed it to me. I wasn’t impressed!
It looked like something you get from a schlocky gift store. But Dante told me that most of what I was seeing was matrix that all comes off. You can literally pick it off with your fingernails. The cleaning appealed to my obsessive nature. I was supposed to get a display of taxidermied birds set up for this weekend’s Fiesta Latina celebration and I couldn’t stop picking away at the matrix and uncovering what appeared to be a very nice print. (I got the birds done later!)
I used ethanol to do the final cleaning, though I’m not sure it clears the matrix from the print. I went over and over the print removing more of the matrix each time. I finally got it as clean as I could and here’s the results. I think this print is ready to paint without any further work on my part.
I wanted to throw in one more issue that has come up with the ObJet print. The matrix is very difficult to remove completely. I spray painted the scorpion with Krylon matte white paint after going over it 4 times with a metal dental pick. The paint adhered, but after it dried, I could remove it with a toothbrush. Dante and Joe from CEID said that sodium hydroxide (NaOH) was suggested as a cleaner by the company who sold the printer. First, I removed the spray paint with acetone, which seemed to have no effect on the printed plastic whatsoever, and took the paint-free scorpion back to CEID. Dante put it into a solution of NaOH. It was left there for about three hours. The solution seemed to loosen the remaining matrix, but it still felt greasy to the touch, almost like there was vaseline on the surface. Dante then gave it a high pressure power wash. After that, the print no longer felt greasy and I felt hopeful that I could paint it now. Unfortunately, I decided to check it with the dental pick again and here is the result:I’m going to spray it anyway and see how it works…Stay tuned. Also, Dante is contacting the company to see if they have any further suggestions for clearing the matrix.