The Pinnacle

[95geo]

I've begun collecting parts for my next car since my first attempt at a berg is showing promising results. So rather than tear up what is working very well, I'm just going to build another one from the ground up.

Chassis- some derivative of the SA 3.5 and RT2 in a bodiless config.

Front axle- stock berg cases, my tubes, VP outers, lots of steering and Super 300HD's

Rear axle- stock berg cases, my super light/super scronny tubes (looking for close to 1/2 the weight of the current 1.4 oz rear pair, not sure if its possible but I'm going to try!), my one piece 7075 rear axles with integrated wheel hex's and somewhere around 1" wider than a stock axle.

HH's new puller motors, the rest is pretty undetermined at this point, it all depends on how the roller shapes up.

Low to even 4 LBS RTR with more metal than nearly (note, I did not say all) any other car of similar weight. It will be roughly 8 oz less than my current car which could still have a lot of weight shed but not without strong considerations to the side effects. Nothing will be consumable or a planned point of wear/failure as a broken car for any reason doesn't finish a course with the least number of points.

Stay tuned to see some progress as parts arrive and chips get made. This thread is going to be for documentation purposes only so others can get some ideas and turn them into their own. If you have anything to say relative to how something will or won't hold up, hold your tongue because you might be suprized!

Enjoy my thread of nothing for the next few weeks and speculate if you care to.

[superduty03]

I like the sounds of this man... Making me want to start another build myself! (Still may once the 300's show up since the current setup is working well) good luck with the build man, I will be watching closely for sure!

Talk to you/see you soon man!

[ittybitty]

No pics? I like the sounds of your axles...your tubes...especially the 7075 shafts with integrated hexes

[Farmer]

I hope you need a tester!
Later,
Farmer

[95geo]

Originally Posted by Farmer

I hope you need a tester!
Later,
Farmer

If anyone ever takes me up on my offer to design parts for them to manufacture, you're in! But....... I think simply talking about making something is enough cause to join the band! O'well, good thing I have no interest in making parts to; uhhhh.... Test.

[bikerj08]

Has your ck chassis shown up yet?

[95geo]

Negative.

[bikerj08]

That sucks, you ordered yours a week before me too. Not too impressed with dhl paket.

[Farmer]

Originally Posted by 95geo

If anyone ever takes me up on my offer to design parts for them to manufacture, you're in! But....... I think simply talking about making something is enough cause to join the band! O'well, good thing I have no interest in making parts to; uhhhh.... Test.

Later,
Farmer

[GEARSCIENCE]

cool

[rob_b]

"The Pinnacle"

Setting the bar pretty high right off the bat. I'll be watching.



p.s. I do better with pictures, reading comprehension is not so good.

[95geo]

Originally Posted by rob_b

"The Pinnacle"

Setting the bar pretty high right off the bat. I'll be watching.

Yep, but the one thing in my favor is that it's all subject able and more importantly, always changing. So I'm going to take what I know about 1:1 vehicle dynamics and what I've learned over the last year about these little creations, then I'm going to take my knowledge of vehicle design, peppered with some of the best geometry I've seen in an rc chassis as a starting point and what'll come out the other side should exceed my expectations and leave me with a vehicle that, if driven properly, will be aesthetically pleasing and very capable/balanced.

Most of the chassis's out there that I've seen are not balanced and have several undesirable traits that leave a lot to be desired, I'd spill the beans on what traits will make a neutral and predictable car with good behaviors but where would the fun in that be?! All I will say is that some chassis designs are closer to that goal than others.

[binaryterror]

Originally Posted by 95geo

Most of the chassis's out there

Just buy a HallStyle...and listen to some Hall & Oates, I hear it works

Good luck Bryce, can't wait to see what you come up with.

[Nabil]

Originally Posted by 95geo

Most of the chassis's out there that I've seen are not balanced and have several undesirable traits that leave a lot to be desired, I'd spill the beans on what traits will make a neutral and predictable car with good behaviors but where would the fun in that be?! All I will say is that some chassis designs are closer to that goal than others.

I'm intrigued to see what you come up with. The high skid height and really low cg on these cars has always made me have to make compromises with link geometries and shock placements

[95geo]

Originally Posted by Nabil

I'm intrigued to see what you come up with. The high skid height and really low cg on these cars has always made me have to make compromises with link geometries and shock placements

A flat roll axis and a wheelbase that has minimal change is where I plan to start, the remaining details are dependent on how you will like things to handle and react.

I have actually been bouncing the idea around of not using springs on the shocks, simply letting the suspension characteristics and external forces dictate where in the range of travel it will be at any given time. This will also make getting the car flipped back over much easier because the springs won't be pushing the axles away from the ground, they'll remain in contact and have more traction. But in order for this to be possible the suspension will need to be VERY neutral, if not, it'll be a crap shoot and probably a large disadvantage.

Anyways, that's enough spilling of the ideas for me.

[Del Monte]

Originally Posted by 95geo

A flat roll axis and a wheelbase that has minimal change is where I plan to start, the remaining details are dependent on how you will like things to handle and react.

I have actually been bouncing the idea around of not using springs on the shocks, simply letting the suspension characteristics and external forces dictate where in the range of travel it will be at any given time. This will also make getting the car flipped back over much easier because the springs won't be pushing the axles away from the ground, they'll remain in contact and have more traction. But in order for this to be possible the suspension will need to be VERY neutral, if not, it'll be a crap shoot and probably a large disadvantage.

Anyways, that's enough spilling of the ideas for me.

Sounds like you're on the right track. I'm curious to see how you solve some of the inherent geometry issues on an MOA.

[95geo]

Originally Posted by Del Monte

Sounds like you're on the right track. I'm curious to see how you solve some of the inherent geometry issues on an MOA.

I have a mental list of things that are being taken into consideration and how I will be addressing them, but in your experiences, is there anything that stands out from your perspective and should be addressed to make a chassis perform better based on the knowledge you have and with the chassis's you've run semi-recently to currently?

I have a week off between the holidays and I'm going to be using some of that time to make the models needed to create a majority of the car. I just hope I get the one key piece in time to make all of this happen, the RT2!

Would you prefer a car that stays neutral (front and rear) on steep climbs so the suspension can stay functional to maintain traction, or one that makes the front suck down and the rear lift slightly, or make the front stay neutral and the rear suck down? This is with traction obviously, when traction is lost the traits will go away. And which ever style you prefer, the opposite effects will show up in reverse.

Currently I'm leaning towards a completely neutral design that will be stable and free of most odd behaviors and one that is very dynamic throughout its range of travel. In other words, when the suspension is drooped out it will want to compress itself into a neutral zone, when it is bottomed out it will want to extend itself back into that neutral zone. And whichever way it ends up, it'll probably only have about 12mm of sprung bump travel from ride height. To make all of those behaviors function as desired the roll axis location and angle along with the wheelbase change, will all need to be spot on.

[Del Monte]

I've found that I like a fairly neutral suspension setup. Combining this with a somewhat lower roll center makes the suspension feel more free and compliant without adding much weight.

I'm not a fan of having a lot of front dive. It might help with climbing, but it seemed to make my truck a lot less stable in every other situation.

[95geo]

Cool, thanks for the input!

[markfw]

"I'm not a fan of having a lot of front dive"
Are you referring to dive, as in diving under power or digging?