River Raiders EV 2012

Catapult Challenge Trebuchet taking shape. Loaded and ready for...

Sun, 06 Jan 2013 18:29:02 +0800

Catapult Challenge
Trebuchet taking shape. Loaded and ready for test fire.

Raiders Relegated to 2nd

Sat, 17 Nov 2012 22:13:55 +0800

This week River Raiders we found out there was an error with the results at the EV Challenge and Team SKM beaten our time in the first race in the second race. Well done to Team SKM and unfortunate that you did not get the recognition on the day.

River Raiders Win Rod, Jamie and Wayne win the open (C class)...

Sun, 28 Oct 2012 07:49:21 +0800

River Raiders Win

Rod, Jamie and Wayne win the open (C class) race and Yuassa class in Roadbot 3 to take the 2012 ITC Global EV Challenge trophy.

Roadbot 3 was consistently the fastest car on the track, even lapping it’s stablemate Roadbot 4. Roadbot 3 had a big efficiency advantage over the 4 wheel car so we could travel a lot faster for the average 10 amp power we were targeting. In the end Roadbot 3 had used only about 80% of its battery capacity, so we could have pushed a lot harder.

Does this prove 4 wheel cars are less efficient than 3 wheel cars? While the cars had identical bodies, batteries, motor and controllers, we feel that there were some drive train losses in the Roadbot 4 that could be eliminated and we could increase the efficiency to get a lot closer to Roadbot 3, although with the extra wind and tyre drag of the fourth wheel and the extra weight of the fourth wheel, axels and diff, it will never be as efficient. On a tight circuit the improved handling cornering might be able to make up for reduced efficiency, but for efficiency races, the question is…. ”Confirmed”

Race day has arrived

Sat, 27 Oct 2012 05:40:41 +0800

Race day has arrived

River Raiders cars to be named Roadbot 3 (three wheels) and...

Sat, 27 Oct 2012 04:40:34 +0800

River Raiders cars to be named Roadbot 3 (three wheels) and Roadbot 4 (4 wheels) for the 2012 EV Challenge
Picture: Roadbot Logo

The cars are finally running with most of the gremlins fixed, so...

Sat, 06 Oct 2012 23:02:52 +0800

The cars are finally running with most of the gremlins fixed, so today we spent some time playing around with gear ratios. It would be handy if we had a quick way to swap cogs, but alas we are getting good at taking wheels off and rebuilding clusters.

Started off with heaps of pickup and felt great on the carpark which is a bit tighter but a run with a pace car on a long straight road only clocked 40km/h. Back to the shed change ratios and we are getting less acceleration but still pulling fine and the top end seems like it will go a lot faster. Unfortunately didn’t get a chance to go back out and measure the changes - a job for next weekend.

Solution to the braking problems found - brake lever with twin...

Thu, 06 Sep 2012 09:55:43 +0800

Solution to the braking problems found - brake lever with twin cables and balance inside.

Test driving the new car for the first time. Brakes fail at the...

Sun, 26 Aug 2012 22:31:44 +0800

Test driving the new car for the first time. Brakes fail at the end of the video but no damage fortunately and easily fixed with improved clamp design in the brake balance bok

It Works A hoot on the gravel, the cyclone motor has enough...

Sun, 26 Aug 2012 10:01:52 +0800

It Works
A hoot on the gravel, the cyclone motor has enough power to get the skinny bike wheels sliding around corners. The first test didn’t last long before the brakes failed, fortunately an easy fix with one of the cables slipping in the balance box.

Photo

Thu, 09 Aug 2012 02:39:55 +0800

Checking the ergonomics of the 4 wheeler.

Mon, 02 Jul 2012 18:41:32 +0800

Checking the ergonomics of the 4 wheeler.

Scooter hack Brief digression from building EV Challenge cars, I...

Fri, 29 Jun 2012 23:51:39 +0800

Scooter hack
Brief digression from building EV Challenge cars, I finally found time to lengthen the back arms of a scooter I picked up at the lions auction for $10 to fit a hub motor I had lying around. So simple, can’t wait to see how it goes tomorrow when hook up the controller. Should be able to fit a reasonable battery pack quite neatly in between the front arms of the frame.

Suspense… Car number 2 this year is a 4 wheeler, so to...

Tue, 26 Jun 2012 23:05:02 +0800

Suspense…
Car number 2 this year is a 4 wheeler, so to keep 4 wheels on the ground, it will be fully suspended. We are using swing arms for simplicity and minimizing suspension componentry in the airstream. More sophisticated geometrical control of tyre angles is not required as we are only using narrow bike tyres.

Build number two has commenced and we’ve now pulled...

Tue, 26 Jun 2012 22:59:04 +0800

Build number two has commenced and we’ve now pulled another couple of bodies off the mould. The moulds required extensive surface repairs after the last demoudling saga, so this time around they were very thoroughly waxed and coated with pva release agent. It worked, the bodies popped out easily by hand. The first (bottom) shell was almost perfect but the second ( top) was a disaster with extensive crocodiling. The gel coat went on on a cold night so guessing the catalyst level was not increased sufficiently and the gel coat had not gone hard enough.
The pink patching shows up the extensive areas that are requiring patching.

It’s time to get back into documenting progress of the...

Tue, 26 Jun 2012 22:52:06 +0800

It’s time to get back into documenting progress of the build after a holiday break and driving across Australia, so here she is in full colour, about a month after Jamie finished sanding the body and painting her. A word of advice, be careful using polyester resin like a paint when not laid up in a mould it stays tacky and was a nightmare to sand.
As well as the finishing the body, Jamie added a new seat and Jamie and Rod completed the electrical system, adding a battery pack. I’ll have to get details from Rod. The first major test was done at the AEVA drive day at the Perth RAC driver training centre track where we also gave a few people a drive including some of our EV challenge opponents.
From all reports (I was away on a holiday) it went well and seemed faster than last years car, but was not clocked on the day.

The first road test was passed on the gravel around the sheds....

Sun, 15 Apr 2012 21:08:44 +0800

The first road test was passed on the gravel around the sheds. The ground clearance didn’t suit the gravel, but it was enough to demonstrate everything is working as designed.

A test on the concrete floor of the shed proved that the steering geometry was working well after being adjusted to increase the ackerman angle after there was some scrubbing with the first attempt.

The car body has now had a coat of primer and is ready for its first real test on the skid pan at the RAC driver training centre in Perth later this month.

The Body Gets a Soul

Thu, 05 Apr 2012 20:22:55 +0800

The Body Gets a Soul

The body is released. Use plenty of wax on the mould or you...

Wed, 04 Apr 2012 08:48:59 +0800

The body is released.

Use plenty of wax on the mould or you will need a lot more wacks with a hammer to get the casting out. We had a few anxious moments when a patch on the mould that was clearly not well waxed decided to stick. It eventually prized away with a lot of mdf wedges, with some of the gel coat of the mould still attached to the body. A bit of damage, but nothing that some body filler won’t fix and a lesson that won’t be quickly forgotten in making sure the mould is well waxed.

Photos showing Jamie in the body before fitting to the rolling chassis.

The bottom half of the body is laid up in the mould. Sorry no...

Wed, 04 Apr 2012 08:42:19 +0800

The bottom half of the body is laid up in the mould. Sorry no action shots, its all hands on deck applying the resin, wetting out the glass and finishing the surface when we are doing the layup.

The whole team got together on the weekend to lay up the...

Fri, 30 Mar 2012 00:23:35 +0800

Inspecting for Bubbles

Making Mould Release Look Easy

The whole team got together on the weekend to lay up the fibreglass moulds of for the new body. The fibreglass work was led by Jamie and it was great to learn techniques, tips and info that made the process successful. Of note was Jamies attention to detail including thick and even gel coat, filleting edges and ensuring no bubbles were present in the layup and always ensure the mix is well stirred. And yes, fibreglass is toxic stuff, smelly, itchy and burns your skin, but amazing how it can create just about any shape that you can imagine.