Matt Bacon Posted May 15, 2016 Share Posted May 15, 2016 I just acquired one of my "Grail" kits -- the Fujimi 1/16 Alfa Romeo Tipo 33 Stradale. It's one of my top 3 car designs ever: The only issue with the kits is those distinctive wheels. Probably because the wheels are moulded in inside and outside halves, the "dish" is nothing like deep enough. These are 13" Campagnolo alloys. Does anyone know of anything that looks like these in the aftermarket? At 13" in 1/16 scale, a set of 19/20" wheels in 1/24 would work as well. Alternatively, does anyone with 3D design skills fancy a quick project to make a CAD file that I could get printed by Shapeways? ;-P bestest, M. Quote Link to comment Share on other sites More sharing options...
Chief Joseph Posted May 15, 2016 Share Posted May 15, 2016 I can do this wheel design in just a few minutes in 3D. I just need some target dimensions. Quote Link to comment Share on other sites More sharing options...
Matt Bacon Posted May 15, 2016 Author Share Posted May 15, 2016 That would be fantastic! On closer inspection, it's a little more complicated than it seems at first ;-PThe real things are 13" rims, 8" wide at the front and 9" at the rear.The kit wheels are made of outside (chromed) and inside halves. All four outside halves are identical.The outside pieces are 24.5mm in diameter, which by my reckoning is 15.4", meaning that the kit wheel size is more like a 14" than 13".Things get weirder when you add the inside halves. The front wheel width is 9mm, which corresponds to a bit under 6". The rear wheel width is 13.5mm, which is the equivalent of 8.5".And finally, the tyres. All four tyres are identical with a width of 15mm across the tread and 10mm across the interior bead. The groove on the rear wheel for the bead is indeed a tad under 10mm. But the front one is under 6mm, so the tyres on the front are simply pinched in by the wheel, and look rather weird.There's also the fact that the attachment for the wheels to the wheel carriers and suspension are different front and back, and the instructions would have you build up the chassis with the inside wheel halves attached, and then put on the tyres and outer halves toward the end of assembly.I'm happy to take some photos of the various bits and measure them up, but I think there's a bit more design involved than I first assumed...bestest,M. Quote Link to comment Share on other sites More sharing options...
Chief Joseph Posted May 15, 2016 Share Posted May 15, 2016 Not really more complicated, just more interesting. I'm just pleased you can use math It's not unusual at all for a kit manufacturer to fudge these numbers a little. Your biggest issue is that the tires are all the same width instead of the rears being a couple of scale inches wider. To me, that throws off the entire look of the model compared to the real car. If it is something you can live with, then it's possible to design the wheels around that problem. Quote Link to comment Share on other sites More sharing options...
Matt Bacon Posted May 15, 2016 Author Share Posted May 15, 2016 Thanks, Joseph...I think the first big decision is whether to use the kit tyres. The width is probably OK for the rears. I think, looking at the tyres, that with some deft scalpel work, I can probably take out one tread zig-zag circumferentially and glue them back together with soft vinyl glue, resulting in a front tyre that's narrower by (conveniently!) 1/16".The alternative is 3D-ing solid tyres as well. That could get expensive, I reckon...I'll have a quick look to see if there are any R/C tyres that might be a viable alternative.So, if we go for the kit tyres, that means that we have to stick with the slightly larger wheel diameter.I'll need to dig a little more closely to see why the front wheels in the kit are so narrow. Looking at the placing in the arches, I think the outside edge is in the correct plane, so I guess it must be that the inner rim doesn't go far enough inboard of the suspension pivot. It's kinda "nailed" to the upright, so there's gonna have to be some thinking about alternative mountings.Thus far, then, I think the external envelope of the replacement REAR wheels needs to be a "plug and play" copy of the kit part, and for the FRONT, it needs to be the front wheel with an additional 2.5mm width inboard, retaining the same mounting point to external rim geometry.bestest,M. Quote Link to comment Share on other sites More sharing options...
Chief Joseph Posted May 17, 2016 Share Posted May 17, 2016 Matt, this discussion is getting a little esoteric for the audience, so I will PM you. Quote Link to comment Share on other sites More sharing options...
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