Quote:
Originally Posted by SlowOne
I had a couple of FF diffs in my Sierra XR4x4, and they were excellent. 
Any of these diffs can be scaled to fit into a model, that's the easy bit. What you can't scale is the Laws of Physics, and they start to give different results when things get bigger and smaller. Those results don't always mimic in a model car what is experienced in a full-size car. The clutch-style LSD might not work correctly when the area on the clutch plates gets to be so small, for example. An example of this is the size of dampers we use. If a TC damper were scaled up to a full-size touring car, it would be so big it wouldn't fit in the space provided, but if the touring car one was scaled down, it would have so little fluid and movement it wouldn't work at all in a TC!
That's the challenge, finding a solution that does what you want it to do. Simply looking to full size and trying to scale it is probably not what is needed. Something different is likely to succeed IMHO. |
Indeed! This was why Team Associated were so successful from the get go! They designed their RC cars as purely RC cars with new ideas, and not trying to downscale a 1:1 car
Those who did try to downscale 1:1 car more than anything else ended up with way too complex solutions, and WAY WAY(!!!) too heavy cars!
We also need to remember the INSANELY big jumps our cars face! Only thing that slightly resembles an upscaled RC as I can think of right now are those Paris-Dakar buggies. They have very long suspension travel and can jump like a kangaroo
Quote:
Originally Posted by Apricot Slice
one daft idea was to have a cog on each outdrive meshing into an idler and then to another cog that carries a slipper linking each side. It was the only manufacturable way within my means to do it as far as last nights thinking was concerned. Probably take up too much space and too much rotating mass.
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I'm no engineer, but that looks like a simple and good solution to me!!!
Quote:
Originally Posted by Razer
Fun fact: My latest ball diff did about 350 laps on Thursday and 440 on saturday, on carpet, and it still feels brand new;-)
Also, the B-fast stuff gets a lot of good words, I'll be trying that soon...
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B-fast stuff???
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But guys, have you all read about this?
http://www.oople.com/rc/photos/euros2010/day2/
Georg Kotzinger from Germany was running a pretty standard looking Associated B4.1 buggy - but we got a tip off about his unique gearbox which looks like nothing special from the outside.
Inside however - he's got something pretty strange going on. The differential is a geared diff that he's been running for the past three years and ABSOLUTELY won't give away it's internal secrets to us mere mortals.
The differential has the usual 'differential' action so one wheel will turn more around a corner but most of the time it locks or has a limited slip action. If the car lifts a wheel when going round a corner for instance, the car wont lose momentum and the wheel with the most grip (the one on the ground) will have full drive. Interesting - wish we could get to see inside! 
If any of you guys were there to see it... did it perform well or not??? Often hard to tell if these home-made solutions are good or not, as "mad scientists" like these seldom are the best drivers...
