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Completion of this project has been almost a decade in the making... Commercial-level high-rez resin 3D printers had been sitting beyond $200,000 for all of the nineties and even when smaller desktop units dropped below $20k by 2011, their build envelope was only large enough to cram 5 or 6 custom ring designs into... IOW, not terribly applicable for 1:10th scale modeling. Jewelry casting resin was $175 a liter. Disruptors came on the scene with their $2500 resin printers. In 2012, this was a downright bargain compared to my first printer at $15k. Resin was "less" costly at $100/liter. Reasonable expense for paying clients, but remains extravagant for hobby tinkering -- and the build envelope stayed minuscule at 5.7 x 3.2 cm. The only way to fit a standard on-road 26mm wheel into this space is to orient it upright. I attempted this very exercise around 2014 but the end-result wasn't worth posting here. Problem? Vertical print position pooled and caused a resin imbalance. The build-envelope constraint permitted no other alternative attempts. The wildly off-balance wheel was only good for shelf display. 2019 is the next watershed year where resin 3D printers have started tickling the $200 milestone. How'd they achieve this? By utilizing super-inexpensive components from the cellphone industry -- deploying a relatively cheap 2k-resolution smartphone screen rather than building a 3D printer around a $1000 theatre projector makes all the difference in final cost. All the buzz became loud enough to take notice. At $200, there are indeed some cheap resin printers cost-wise but also cheap in quality; questionable design features abound. Experience proved invaluable in identifying features to avoid. The standout winner worthy of a spot in the stable is the Elegoo Mars at $250. Jaw-dropping price point no matter how you cut it. Tons to like: Stretched-film release design similar to my $15k printer suggesting low-maintenance workhorse reliability/repeatability. Superb Z-axis rigidity using a linear-rail like design. A wobbly Z-axis arm can cause disastrous banding in the print. User-replaceable critical components as demonstrated by their own instructional YouTube videos. Crack the masking screen? $40-ish replacement makes things right. Considerable leap in the build envelope. The Elegoo is able to print what fits within 11.9cm x 6.8cm (x 15.5cm height) and still maintains a 50-micron resolution. Color touch-screen control. Files read off a thumb drive. Prior resin printers mandated tethering to a dedicated computer to drive the projector. (itself limited to a bulb lifespan) After running a few calibration tests (largely unnecessary and for my own satisfaction), it was time to address my long awaited project. 26mm width BMW Style 35 wheel fitted to a Tamiya hex hub. Elegoo Mars 3D printer. Quickly Glowforged a pedestal storage box for it and made sure there was resin on-hand. One liter of their resin is just $45. Third-party resins can be used as long as they're formulated for these kinds of masked-SLA printers. Laser SLA like Formlabs and Moai require different resin formulations. Still, not many are gonna beat $45/liter! The free support & slicing ChiTuBox software has quite a bit of nice features coming from this veteran resin jockey. The ways to identify & edit supports for undercuts or floating islands is praiseworthy. One nit is that there's no apparent publicly centralized data pot for exposure times for Elegoo resins. Possibly walled off in their Facebook page. The product box only provides a range -- thus my initial tests. Small-object test prints suggested that my settings for Elegoo Black Resin be 60 seconds for the first 5-6 layers and all subsequent layers can be at 6-seconds exposure. As shown here, the represented build platform has plenty of space to accommodate an on-road wheel. For reasons outside the scope of this hobby forum, a flat lay-down positioning of the wheel isn't necessarily the most recommended, but I've printed using two alternate ways and got away with successful prints. ChiTuBox goes as far as asking how much I paid for this batch of resin and can calculate the projected volume of resin used and total cost of parts put on the build platform. Let me do the math for you.. a liter of resin ought to yield around 66 Tamiya wheels. Toss the sliced file onto a USB thumb drive and feed it to the printer. Here's the angled & supported version... What kind of detail does 50-micron yield? Hex heads on the lug bolts resolved with a faithfully reproduced dimple at the center of every one! Here 'tis mounted to the M-04L chassis... spins just as nicely as the Tamiya-made wheels. No off-balance issues. Giving the back part of the rim a squeeze shows that it takes nearly DOUBLE the effort over Tamiya's ABS plastic to start deforming. At roughly 1mm resin wall thickness, the toughness observed so far suggests it would fare no worse than manufactured wheels. Once I get my hands on more resin vats, I'll dedicate each one to their own resin making for super-quick printing material changes... black, grey, white, translucent, etc Now all the things that normally get scuffed up (side mirrors, body posts) can be easily and affordably re-grown on the high-res 3D printer. Onto the possibilities of fabricating all the details I only dreamt of decades ago... windshield wipers, light buckets, suspension arms, action cam mount...