
In an earlier post I wrote about how I finally reached the conclusion that my mineral wagon bodies should be made of wood and brass.
It took me some time to get to that conclusion, and believe me, it wasn’t just a mental process. The pile of rejected body parts in the picture should be proof enough of that!
At the beginning of this project I cajoled a good friend into laser-cutting parts for the wagon body in thin plywood. The parts came out crisp and with very little black crud (or ash you might say) at the edges, but they had a two-dimensional feel that I did not care for. I thought about laminating two layers to build up more bulk, but as the edges of the ends and top of the sides are visible, it did not seem like a very satisfying solution. So those plywood pieces became the foundation of the still life.
The longest detour was due to a hang-up on 3D-printing. Several test parts were printed. First, I had a lot of very promising prints made by the pioneer company Print-A-Part. Print-A-part did unfortunately go out of business, and I have a sneaking feeling that demanding and rather uninformed customers like me were at least partly responsible for this. As amateurs, we demand the best, but are not willing to pay more than peanuts. Most frustrating, because when all the planets aligned correctly, the PAP parts came out almost perfect. But the results were not consistent. This led to a lot of frustating email exchanges about things like part orientation and other remedies to get consistent results. I fully understand that the parent company of PAP, Fine Line Prototyping, decided to concentrate on the professional market! So the PAP turned out to be a dead end in more than one way.
With PAP no longer an option, I decided to try Shapeways services. Shapeways has built their whole infrastructure to serve amateurs and semi-professionals, and they seem to have managed the challenge of creating a 3D-printing service for the masses. I have nothing but praise for the speed and reliability of Shapeways services. Their web-shop is excellent, it is very simple to upload .STL files and order prints. A lot of modellers use Shapeways with excellent results. The results you can get with their best material for detailed scale model parts, FUD (Frosted Ultra Detail) is almost, but only almost good enough for even the most critical modeller. So my test prints for sides and ends were reject for three reasons. First, the detail was not quite crisp enough. Second, they were not solid enough. And last, FUD parts has a sticky residue that is a pain in the proverbial to remove. So the parts ended up in the still life. But there will be some SW parts on the wagons, the coupler pockets are printed in wax and cast in brass by SW. This is a very interesting service that is totally dispruptive for traditional lost wax casting services. I can not wait for the next generation of Shapeways printing services!
The last of the 3D-printing test-matches involved a 3D printing service provider in Seoul that due to the wonders of Google translate ended up printing six wax masters for brass test castings of entire wagon sides. The results were again promising, but the Solidscape printer did not have good enough resolution for the cracks between the boards to show up. And a wagon completely out of brass would be rather massive. Heavy metal, indeed. Another very costly lemon for the still life.
I admit to having a CNC-hang-up as well. This hang-up is fuelled by the extremely good results modelers like Fridtjof (Check out his work on the Westlake modellers forum or Buntbahn.de) cranks out using hobbyists CNC-routers. This is pure modelling pornography, and it is impossible not to be inspired. So when I got access to a High-Z s-400 router I immediately started to mill profiles in brass for the frame. I did not quite get the results I had hoped for, so even if etched & folded profiles are not quite as crisp as milled brass profiles, I settled for this compromise as the etched profiles are much cheaper and simpler to make. Milling brass on light CNC-routers is quite nerve-wrecking and rather frustrating. I will probably try again, but for now the milled end beams belongs in the still life. Even if strictly speaking, they are not body parts.
I hope that this little tale does not come across as complaining. Quite the opposite, I really enjoy experiments like this. Every piece of the still life is a lesson learnt, and I really needed the reality check on 3D-printing and CNC-everything. But receiving all these little packages in the mail is better than most Christmas and birthday gifts. They really add a little excitement to checking the mail box. Even if the gift in the end turns out to be a trinket for a still life.