Blender's TRX-4M as Superduty "ute" with aussie style tray

[Blender]

Got back into crawlers again, but scale now is way more advanced than before. Started with a TRX-4M. Didn't even finish off the battery before it was in pieces. It's a pretty nice little machine to be honest. It will be rebuild as somewhere between an overland style truck and a service truck. Will play nice with my 1:14 scale semi trucks and still technically "micro" in 1:14. Don't expect it to crawl great, but should look the part.

• TRX-4M bastard axles- stainless steel tubes and center section, Meus pinion mount/gears, stock diff cover/bearing support. Stock CV joits, axle C and Hubs. Construction will be tiny welds.
• Superduty SLA body
• Flatbed/Tray like the aussies use, but in stainless steel sheet
• Suspension: front might be ford-style radius arms in stainless steel. Rear will be stock -4M links
• Transmission unknown, maybe just a planetary gearbox and 1:1 transfer case
• Motor: HobbyWing mini16 - looks like i'll have to turn down the motor shaft to 2mm
• Wheels/tires: 65-70mm OD is slim pickings. RC4WD Lego series is my best option now. Ideally 1.2in wheels or so to be scale-ish. Wheel will likely be SLA printed since Meus stuff is too much offset
• Some blinky lights
• 2S lipo
• Jeti radio shared with all my toys

Body STL file was bought from Cults3D and scaled to 1:14. Pieces were combined to reduce print cost-- Slight fitment adjustments are needed

Taking half of a Meus Axle and half of the stock traxxas creates this chunk that holds all the bearings. Now i don't need to mess with cutting/printing bearing pockets. Clamp thickness will be tough to match on the axle body. Need to cinch down on the bearings just as the two halfs clamp to the axle housing. Going to be hand-fit.

I will order the purple part to link up the off the shelf parts. Short side axle shaft is stock -4M. Long side will need to be extended. Outer Cs and knuckles will be stock. Varius tabs from stainless steel sheet will be laser cut and welded on. Tubes are 5/16" OD .028" wall. Pretty close to a scale 4" axle tube. Ends will be turn down to press into the purple part. Some welds along the outside for good measure.

160" wheelbase in 1:14 scale. A bit of a trail limo. High CG thanks to the metal bed. STL of the body is huge in terms of file size. Had to reduce/omit to get it to show in CAD. Was printed at the original higher-mesh.

Weld teaser on .5mm stainless. Tray will be ~0.8mm with some 1.2mm here and there.

 

[Saltrock]

Reading through I saw you say weld a few times talking about the axle housing. I kept thinking “when you say welds, what do you mean?” lol. And then I see the pic of the weld, “oh, that’s what you mean by weld, lol”. Very nice work and that weld is… chefs kiss.

 

[Blender]

Thanks! It's a fusion weld, no filler. An increase in capability over soldering/brazing everything. The abundance of laser and waterjet cut sheet metal parts has been a game-changer.

 

[Blender]

Now we are in the physical build:

Tacked together to check fitment. Not too bad. Drawer will house the lipo so body mounts can be stationary. That's a TX lipo from another low amperage project. No idea what the mini16 actually draws in terms of current, but i should be able to fit an alternate pack if needed.

Storage boxes are next. Was originally going to have them open/close, but i'm not really feeling it. Going to be simple non-operational boxes.

Wimped out on the diff center section as a machined part. Did a print first to check fitment. I'll commit afterwards.
Settled on a set of Injora wheel/tires at 70mm OD. Roughly a scale 38" which should look about right.

 

[Saltrock]

Killer, that battery tray is sweet.

 

[Gula]

Yes it is!

*Edit
After further review, I must recant my statement, and apply that to that whole bed setup!

Wow! That's killer, and you said it's laser cut?

 

[Gula]

What would be cool is if you had a vendors star and sold these as a fold to braze yourself together deals. Truck tool beds/boxes, just saying..........

 

[Blender]

What would be cool is if you had a vendors star and sold these as a fold to braze yourself together deals. Truck tool beds/boxes, just saying..........

Hmm. I'm not opposed in the future. Been working on another hobby's parts as side hustle, this would be "easier" in comparison. I'd probably adjust the design a bit to include a few screw connections to ease brazing fixturing. Holding parts in place was always my struggle with brazing... And melting nearby joints accidentally.

Parts are 304 stainless laser cut from Send Cut Send although many places offer such a service. Just a little touchup with a file at the tab edges is all they needed. I'm usually slow to paint which I why I use stainless. they won't rust on me. Thickness is .030" 0.8mm.

 

[Blender]

Did some super sketch lathe work to make a Mini16 fit where it shouldn't. Case is not obvious for disassembly like the bigger 540 sized Fusion Pro so I improvised. Chucked the entire motor in the lathe and ran the mini16 motor to turn down the shaft to 2mm. It's so quiet and can spin so slow a few times I was trying to measure the diameter while the motor was still running. Shaft is soft near the tip, but feels hardened closer to the motor face. Kinda weird.

From running this little motor it's great. Super quiet, good torque and spins so slow with authority. Power supply was reading 750 mA current draw at 7.5V while I was cutting the shaft down. Looks positive for keeping a low C battery. Make me want to put this motor in everything.

All I have on hand is a 62:1 planetary gearbox. Numbers say it will be way too slow on 2S. I'll use it for mockup and swap it out next time I order stuff. Transfer case will be a 2:1 Lesu unit. Divorced mounting from the gearbox. I'll turn down the input and output shafts to 4mm so everything matches

Still dreading the last of the bodywork. Needs adjustment to get the A pillar/Fender/rocker panels all looking right. Slight warpage on the print and some inconsistencies from how I merged the STLs. Shoulda asked the file creator to merge for me.

 

[Blender]

Front D60 with a printed center section. Final will be steel. Short side shaft is stock length and engages into spool. Tire clearance to radius arms is going to be tight.