Brat Project - Short/Narrow chassis w. Mini body
Welcome to my project - an ORV chassis with a 210mm wheelbase (obo 40mm shorter) to fit a 58211 Rover Mini Cooper shell. The chassis has also been narrowed 10mm in the front and the back to fit she shell better width-wise.
I wanted to build an ORV chassis that was unique. Hopefully this submission will be unique enough to be included in the ORV space frame member group. This is still a project in the works but I was so excited I had to post. INSPIRATION: I was inspired by the full scale hot hatch trend of fitting 13inch diameter wheels with wide widths and stretched low profile tires. I already have a Brat and a Ford 350 Truck built on the ORV chassis and I wanted a car instead of a truck. But I wanted it to look better than the old Lancia did. CHASSIS: I wanted to retain the stock ORV plastic chassis. I took about a 40mm section out of the top rail behind the front servo mount, and used a plastic rail (from the rear servo mount) to reinforce where I made the cut. Glued with CA glue and screws to reinforce. On the bottom, I used the screw holes for the metal skid guard and made some aluminum plates to mount to the under reinforcement of the chassis. This part is strong. NARROWING: To narrow, I took 5mm off the front bulkhead where the suspension mounts on each side. This did weaken the chassis a bit. The first one I made cracked here when my son hit a pole with it. V2 notched the metal suspension mounting on the bottom and narrowed the plastic on the top - this way is much stronger. The wheels now tuck halfway under the Mini Cooper shell and do not fowl the body. To narrow the rear, I took 5mm off each trailing arm. Basically, trim off the bearing race recess on the outside. Then, drill out the plastic behind it to fit the bearing back in (you need two to fully support and locate the axle. WHEELS: I used the stock Brat wheels in front and back. The tires are actually stretched 'Smoothee' front ribs from the Hornet/Scorcher. They were difficult stretching onto the rims, but I think they are awesome! The inner bead is the correct diameter, just needs stretching to fit. SUSPENSION: I used Tamiya CVA plastic shocks, 50520. They work the best on the ORV chassis because they offer the proper amount of travel. I fabricated a custom front bulkhead shock mount out of sheet polystyrene. I was going to do fiberglass but the poly is light and strong enough. BODY MOUNT: I used the stock holes in the Mini Cooper body. The front mounts are attached to the custom shock bulkhead mount. Then there is an intermediate plate that holds the rear mounts. That plate is mounted to the stock rear Brat mounts for the Styrene body. FINISHING: I plan on a Union Jack paint scheme for the shell with a Brat driver. HANDLING: This thing handles GREAT! The short wheel base actually makes the chassis more nimble. With the slick ribbed tires, this thing actually Drifts! It's a ball! It runs circles around my other ORV chassis models. I have been running this for about three weeks now and I consider it fully tested. This is actually the second one I built, learning from the first. You get much more suspension travel than the stock M Chassis - you can set this up for off road, jumping - all the things you can't do with the stock Tamiya Mini. I feel like it is perfect now. I'll post up again after the paint and driver are done.
Comments
mikeekim
rally mini, awesome
Origineelreclamebord
Looks like a fun project!
Corona Powered
Thanks for the comments. Work continues. I felt like the front track still had to be a little narrower. So I shortened each of the front suspension links about 2mm. Then the suspension wouldn't work right. So I had to design a new front shock tower. But I finally got it sorted. It runs and looks perfect now. I also painted the shell. I will be posting finished pictures as soon as the weather improves.
Want to leave a comment?