Newly printed model called Robotta (search it on Thingiverse if you want it). I’m going to experiment with this guy a little bit. It’s made with ABS and what I’m going to do is try to force ABS to set beyond what extrusion at 240C can offer. Just thirty minutes ago I’ve exposed Mr. Robotta to a gargantuan (you really don’t get to use this word in a sentence too often) amount of 405nm light. If I’m right the model will get more transparent and more brittle within 72 hours.
Polymerization does not stop once the temperature of plastic is lowered. It continues and changes the properties of plastic as it goes. HDPE takes about 72 hours to set. I remember one time when I was working in that industry our company send a whole truck full of HDPE containers to a client right after it was manufactured. When they got there necks of bottles shrunk enough for their quality control to notice that “Theese 'darn bottles leak out our oil”. They returned it. Now you sir are correct in your assumption that sunlight has plenty 405nm light in it’s spectrum, what you came short in your thought process is the amount of light used to cure this model. I used word “gargantuan” and I mean it. I took about 15 minutes going through this model with a 2500mW laser. I have tried curing a one other item I’ve printed as well. After two weeks it does look different.
@ilya_svatutsa , can we see pics of the “before & after” of the other item that you cured?
Thank you
405nm is near-uv, not uv.
@Ivan_Hoe Here is a comparison of that item to another print made from the same roll of ABS: https://plus.google.com/u/0/+ilyasvatutsa_roseville_MN/posts/9jZk5YTiegP?pid=6275730250188670850&oid=117344282240615327093