I’ve wondered for a while if it’d be possible to print walls, such as brick, for HO scale models. Not because it’d be the most efficient way to get brick sheet but because I didn’t have any brick sheet, and have some brick buildings I want to build, and I have a bunch of filament and a 3D printer why not try.
Live has kept me busy but I finally got around to it and modeled a parametric brick sheet in OnShape. My first attempt was using a 0.4mm nozzle which is the stock size for my printer… it was so bad I disposed of it immediately. I more recently tried a 0.2mm nozzle and had a little better results.
My first attempt exactly off standard dimensions as I found them online. This looks good in cad but just didn’t have enough definition. It was so hard to see straight off the printer I painted it white and then covered in a red. The hope was to catch just the brick faces and leave the white mortar.
That didn’t really work, a wall of it might pass as brick but just didn’t feel detailed enough (and would be nearly impossible to try and lighten the mortar lines as they are just too shallow and narrow.
The next attempt increased the depth and width of these lines (which was really easy thanks to parametric CAD!). This had better results in my quick paint test.
It was definitely an improvement* but I didn’t like how the gap was narrower on the horizontal to ground lines but bigger on the vertical (and this maybe a printer belt issue that’s too small to have noticed previously) and the inconsistency with the brick face bugged me a little so I made the bricks a tiny bit shorter and the horizontal gaps the same amount bigger.
Pulling it off the printer immediately showed the improvement* but painted it really seemed to pop a bit more, especially at a distance. If you get up really close the mortar lines look a little big but I’m thinking that looking good at 3 feet but maybe not 3 inches is better than looking good at 3 inches but not 3 feet.
Certainly there will be more experimentation but looks promising for printing larger wall sections than say Walthers modular system, and with details like doors and windows exactly where I want them… and without having to run to the hobby shop for supplies 🙂
For my quick tests I also found another use for my printer, specifically the part cooling fan. It makes a great small part paint dryer
* I typed this post up as I was printing and painting these tests but since it was getting a little late I called it a night with the intent of taking pictures the next day and finishing up the post. The next afternoon I didn’t really have time to finish the post but decided fairly quickly that my opinion from the night before was wrong and that the first batch looked better just with a little under extrusion problem on the bricks. I ended up comparing it to a commercially available brick building and the second two attempts ended up looking fairly bad in comparison with giant gaps between the bricks.
So from here I’m going to try and adjust the model back to what I had originally and change my painting method. Rather than painting red on white going to paint them red and then use a white wash to try and get the low spots which might work better with the smaller gaps
Matt's Railroad Blog 