Grey Resin

I've not had much time recently for modelling but today I set another test print running in my new 3D printer, not only to try it on a more detailed model but also to try a different resin. The default transparent green resin worked well but looks odd so I thought I'd try a more normal looking grey resin.

As you can see I printed the Sand Hutton Wagon which stalled because I couldn't get decent prints from Shapeways. On an initial look at the prints I was blown away. The crispness of the detail and the smoothness of the surfaces easily beats any prints of this model I've ever had from Shapeways. The underside of each part is deliberately less detailed due to the way they are supported while printing, but I can probably live with that. There are issues though.

First up, the floor of the wagon is missing plank lines. I'm guessing this is because the lines are quite thin, and unlike the sides of the wagon the whole floor surface is cured in one go, and the UV light has bled through enough to fill in the gaps. This could be easily fixed by widening the gaps ever so slightly.

A bigger issue though is the underside of the parts which is frankly horrid. It's all thick and bumpy. My feeling is that this is a combination of the grey resin being a little thiker so it doesn't run off as well when the layer is lifted, and that the part was printed parallel to the build plate. This means that when the layer lifted it held on to lots of the resin which cured slightly when the next layer was printed. It may be that the green resin would give better results as it seems to pour easier, but also tilting the model slightly so that the floor is printed in stages might also help.

So more experimentation is needed, but I'm getting there, and looking at the detail on the wagon sides, if I can iron out the teething problems the printer is going to be fantastic.