3D Printing - "It's all about design and quality output. Not how fast the printer can run."
The camera doesn’t know how to manage an exposure using a lot of UV light. It’s close to what it looks like with the human eye. Some colors fluoresce under UV light. This is one of two 10 watt UV lights I am using.
Most of the resin I intend to use with my WD7 printer requires a UV after cure process. The parts could be set out in the sunshine, if the sun is shining. The more controllable process is to use a UV cure box and put the parts inside the box with UV lights to cure. Faster and more controllable.
I like building most of my machines and building a UV cure box is not much of a challenge and is fun to do. It doesn’t need to be very big for the size of the prints that the WD7 can produce. This box is only eight inches square.
I have my homemade HB2 CNC router and this is a good project for using it to make the parts. I am using low cost 5/8 inch wood fiber board. This is not the high quality MDF. It’s the coarser material that Lowes stocks in 1/8 sheets. (2’x2’), 33% more material than is required for this project.
I used my table saw to cut all the parts to exact size. It’s far less waste than using the router to do all the cuts to size. I have a nice 8” x 24” board left over. Then the router is programmed for the top and bottom edge recess and the recess for the turntable on the bottom center. Two of the sides are cut through for mounting the UV lights. The base of the lights get warm so with the fixture totally outside the box, the box will be cooler. Heat is not required or desired to cure the resin.
I use Vectric Aspire to create the CNC path files. The computer pictures (below) of the parts are produced by Aspire
The proof is with the next print job when I will have some objects to cure. I think it certainly more UV than sunshine. I picked these lamps as they emit UV at the correct wavelength for resin curing, 395nm - 400nm. Energy is not wasted at the wrong wavelength.
"Holy poker chips batman!" I poured about 3/16 inch of raw resin into a small plastic cup. Then I placed it into my curebox. I filpped on the UV lamps and checked the small cup about 60 seconds later. The resin and the bottom of the cup were so hot I couldn't touch them. The top of the cup and the rest of the box was cold. There was a good wiff of cured resin.
The resin had completly hardened through in less than 60 seconds. The reaction is certainly exothermic because of the heat in the material. I would call it an extreamly rapid reaction. I certainly have enough UV power available. I left it in another four minutes, just to be sure. The picture shows the poker chip I made. 20 Watts is probably overkill. I have a real part printing and will test agin. I think I have a very good cure box.