Brimod Prototype Car

[dinglem]

No not my design - i just saw those and told him they were just what i wanted. He is also in the process of making a set of the 'standard' Pro Radiant smooth dish rims as well, now that he has the measurements, but these look WAAAAAAY better!

[Coelacanth]

I agree, they do look way better. I find dish wheels boring. If the Radiant dish wheels weren't gold-plated, they'd be nothing special, to be honest.

[dinglem]

Had a go at cleaning up one of the front shocks last night, and it really came up well, especially considering how poor they originally looked when the car first arrived.

I also trial fitted one of the hex rears to go with it - looks great!

[Dadio]

Just looking at this car I start to wonder what the price tag would have been if it went into production ? A lot more that my pocket money would afford as a 15 year old I'd guess

[dinglem]

Some RC cars look like toys in my eyes; this certainly isn't one of them! Every component seems to have been thoroughly thought out and then totally over-engineered. It's a thing of beauty and there are immaculate details all over it.

I couldn't even afford a pair of Brimod shocks back then, let alone an entire Brimod car

What is good about it though.... if you break a wishbone, you just have to cut a matching piece of fibreglass (i plan on getting some spares cut prior to use). Drive gears are just pinion gears. Drive shafts are rebuildable Brimod items.

All of the aluminium components should break whatever you hit rather than the other way around...

[jwscab]

You would more likely rip threads of out the aluminum parts of the arms before you broke the fiberglass.

Very interesting setup. I wonder if the extra layshaft was a solution due to an oversight on the motor rotation/gear drive on the diff/front belt. The motor could have been flipped left to right to alleviate that, but maybe the chassis parts were already cut. It's certainly something that would happen to me hahhah.

[Dadio]

I can't see the double lay shaft as a bodge , at first it kind of looked that way to me , maybe a measuring error and they saved the proto chassis by bodging up a solution but then why go to the trouble of making the machined aluminium cover ? I've done similar bodges to save time and money but I would not then waist time and money making the cover ? No I'm sure its deliberate and the more I think about it its got to be to reverse the drive direction , that makes sense as well as the option of further ratio changes .

[GoMachV]

...maybe the chassis parts were already cut.

I had considered that as well but the plates could have been swapped left to right to flip it. I suspect the reason for the idlers were taking into consideration the gyro effect of the motor. The way they made the gears easily accessed makes me think they wanted it for more radical final drive changes but as he mentioned the housing isn’t large enough. They could have easily fit those two gears inside the chassis had they wanted to, so there is some reason for it. I am sure once it is revealed it will be a ah-ha moment.

Did their 2wd prototype use the same idler configuration?

[dinglem]

Probably correct about that. Main aim will be not to crash it!!

I can't imagine they had any oversights with the drivetrain, or any other part of the build. They were known for being super technical and clinical. They had produced a pair of 2wd cars at around the same time, and that had a belt drive system to the rear wheels, so perhaps they were also looking into that for this car? They certainly looked at chain drive as they also produced front and rear chain driven gearboxes which came with this car when i bought it, although i still haven't quite figured out how they fit/work at this stage.

I am still hoping to get in touch with any of the old Brimod team to find out more about this car, but i haven't had any luck thusfar.

I spent this afternoon working on the shocks some more. The fronts, though cleaned up, had a major issue in that the hex thread adjusters were jammed solid. If you look at the earlier pictures the initial ones show the entire units as being in a very poor state and corroded slightly in some areas. It was a real job to get them looking decent. I gave the threads a good scrape out with a fingernail, then a toothbrush with a little household soap, and then left the entire shock unit soaking in WD40 for a few hours. Then it was a case of carefully clamping the shock body itself in a vice and locking a spanner over the hex and gentle wiggling it back and forth until eventually it began to move..... little by little it freed off and once the bound area was cleared i could clean and lightly lubricate the freshly exposed thread. The first one is done and now spins very freely indeed. Quite a relief as i have never seen another pair of hex fronts. I am now soaking the second front as i type.

The next thing was that the trial fit of the rear hex shocks had identified that they were a shorter throw than the original Brimods that were on the car when it arrived. By quite some margin in fact. I was curious as to why, as the body length was identical between the two versions. I ended up stripping one of them to reveal the old silicon tubing trick; the same thing we used to do for our carpet racing Mid in order to limit ground clearance and improve indoor handling. This version was a bit posher than our chopped piece of silicon though, as it was mounted on a brass slider.

With these removed the throw length is restored and back on the car they now look and feel fantastic. They are mounted on the screws with a thin silicon collar (rather than the usual stepped plastic sleeve) which is kind of cool and seems to make the movement a little smoother somehow. I have also switched the upper screw direction to allow me to add some wing mounts at the back of the shock tower.

Sorry for the picture heavy posts, but i am really rather enjoying working over this car. Once the remaining front shock has finished soaking and has been freed off i will start looking at the diffs and drivetrain.... kind of putting off stripping it down but have to go for it eventually....

[Dadio]

You got to get rid of the red on those wing mounts and strip em back to bare ally ! I'm sure you already were going to but I had to say it .

[dinglem]

Just managed to free off the second front hex after much jiggery-pokery.... The difference is quite remarkable and they have eventually come back to life and almost look like new after quite a painstaking few hours.

It is really starting to look like i am making some progress now. I have also cleaned off a bit of servo tape residue from the inner chassis rails - which clearly suggest it has been used (supported by the black markings on the belt tensioner). I also cleaned the steering system up a little and in doing so i also noted that it actually has quite a bit of steering lock - more than i was expecting anyway.

My next lesson to self:- do not try to strip anything without taking plenty of pictures of it first

I thought the belt tensioner looked fairly straightforward so had a go at stripping it for a clean. Lordie

It came apart MUCH easier than it went back together again, that's for sure. The main issue i am having with the whole car is that there are loads of C-clips holding many of the components in place. Not necessarily anything unusual, but i am at work, on a ship, in Mauritania, and i literally just have the car here with me. Tools are from the ship, but i do not have one single spare C-clip. Needless to say i have already had several hands-and-knees session looking for a pinging C-clip which has vanished to the floor upon removal or attempted replacement. Thankfully, for now, i have the full set still. The belt tensioner also uses them and being housed within the central drive channel this was very tricky to do, especially when going back together. The rollers are both ballraced and the bearings got a good flush and soak before it all went back together again. Pretty neat design, which looks a lot better now it is clean and spins nice and smooth.

That's all for today i think. I'm still putting off breaking it down to get the diffs out!

[dinglem]

You got to get rid of the red on those wing mounts and strip em back to bare ally ! I'm sure you already were going to but I had to say it .

Yeah, i know. I'm pretty miffed with myself to be honest, as i have two identical pairs at home and i grabbed the red ones rather than the silver ones by mistake when rushing to pack. Arseflakes.

Nice to know you're thinking along the same lines as me though

[RC10th]

Maybe you should use some good bowls for stripping the diffs to save more hands and knees looking for diff balls

[Dadio]

I used to work as an AA Patrol man (mobile car breakdown mechanic if you dont live in the UK ) and a useful tip when taking appart anything that might spring of is to use a large clear plastic bag , work inside the bag , then if a circlip fly's off its in the bag , if you put a hole in the bottom of the bag its easy to have both hands in there , at the roadside if something sprung off it was a knightmare especially at night !

[dinglem]

Are you happy now Dadio?