As stated previously the clear plastic molded original wheelhouse was lost somehow during the 10+ years of storage at my parents' basement.
I decided to go the 3D printing route to build the replacement part.
While the shape of the wheelhouse is very simple, it still took some time to get the basic of 3D solids modeling to get something that would look passable.
3D model was based on measurements on the 1:1 plan supplied with the kit. I also used pictures of the Gruno V found online.
My model differs slightly from the real thing. To keep the design simple, the wheelhouse is actually just a half shell which is then mirrored into a complete structure.
It also lacks the slightly rounded shape of the front.
Once I had the 3D model it was time to print a prototype. I got my 3D printer a few days ago so I'm still new to it. I also only have PLA while I intend to print the part in ABS which has physical properties a bit more appropriate but is trickier to print.
Once your 3D model is ready you feed it to the slicing software that comes with the printer.
Based on your settings, the software will slice the model into hundreds of layers. The slicer can also add support structures under zones that would otherwise "float in the air".
As you can see on the "sliced model" above I decided to print the wheelhouse upside down to use the ceiling as a good solide baseplate.
Support material (blue-green) is added by slicing software because printing "mid-air" is not possible. You can achieve so decent overhangs depending on the angle (45° seems the reasonable limit). A fine-tuned can even print straight lines above two centimeter gaps but the windows of the wheelhouse are too high and too wide to print unsupported.
And off to the printer ...
And now the result ...
This is actually my fifth print with my 3D printer. It took approximately 15 hours and 155 grams of PLA (including support structures).
Printing raft and support structures were obviously removed before pics were taken. Some quick deburring and sanding too.
The walls and windows look very decent. Some light sanding will be required but I think primer would even things out quite easily.
The steep taper to the ceiling - especially the corners - on the other hand don't look so great.
The tapered section (and the small rounded windows) were printed without any support.
Things to test/improve:
Final part will be printed in ABS (which I currently don't have hence PLA) which will probably also incure some tweaks.
Overall I'm happy with this print. As with any technology there's a learning curve but so far even with my limited experience things are very decent.