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Old 11-19-2010, 11:40 AM   #61
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Just build it! Alphacat will want a sackfull of them, I will borrow one of his, he won't see it for at least a year, I'll tell everyone it's a protoype and they can't have one right now, only special people can be on the list. The orders will flood in...easy!
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Old 11-21-2010, 03:34 AM   #62
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Err... to me both raising the front pivot ball of a tbar or the front pivot bal in a decently designed link car are different from each other and also different from just lowering the roll center.

Angled side link would give rear steer, in one direction or the other.

Angled t-bar or angled pivot balls axle... you might lower the RC a little bit, but then again this induces so many other unwanted effects that I can't see it used , except may be with a very thin shim, if you're a setup guru. I can remember that richard Chang's 1/12 cheat sheet mentions it, but can't remember what it's supposed to do.

I'm from Geneva. Have we ever met ?
On a standard Associated-style t-bar, the rc is at +/- 11mm (at 5mm ground clearance). A 3mm shim under the front pivot lowers the rc a bit less than 3mm to 8mm (Still high over the ground). But it gives rear steer, thats right.

Rc at or below the ground is (using a t-bar or traditional link system) nearly impossible. But there a some link designs, that can reach rc's below the ground (Rc-devil, for example)

Geneva? I was 1 or 2 times in Preverenges at the HPI-Cup, but thats some years ago. At the moment, I only race 2 or 3 times a year


@Mantisworx: As long as it works good on the track, there's no reason to change your suspension. Theoretically, a tradititional link-car wouldn't work either, but with some flex and slop, it works amazing.
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Old 11-21-2010, 05:05 AM   #63
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On a standard Associated-style t-bar, the rc is at +/- 11mm (at 5mm ground clearance). A 3mm shim under the front pivot lowers the rc a bit less than 3mm to 8mm (Still high over the ground). But it gives rear steer, thats right.

Rc at or below the ground is (using a t-bar or traditional link system) nearly impossible. But there a some link designs, that can reach rc's below the ground (Rc-devil, for example)

Geneva? I was 1 or 2 times in Preverenges at the HPI-Cup, but thats some years ago. At the moment, I only race 2 or 3 times a year


@Mantisworx: As long as it works good on the track, there's no reason to change your suspension. Theoretically, a tradititional link-car wouldn't work either, but with some flex and slop, it works amazing.
OK

Sorry to be so stubborn, but I just don't see how a Tbar car could have the roll center anywhere else than in the middle of the pivot ball - let's suppose it's horizontal for the sake of the discussion.

Admittedly , a traditional link car isn't perfectly mechanical, but the matisworx rear end makes it A LOT worse.
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Old 11-21-2010, 07:25 AM   #64
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The sprung mass rolls around the axis, that is given by the 2 pivotballs. The rc is on this axis, but behind the pivot balls (At the position of the rear wheels).
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Old 11-21-2010, 08:30 AM   #65
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OK

Sorry to be so stubborn, but I just don't see how a Tbar car could have the roll center anywhere else than in the middle of the pivot ball - let's suppose it's horizontal for the sake of the discussion.

Admittedly , a traditional link car isn't perfectly mechanical, but the matisworx rear end makes it A LOT worse.

and you know this because you have driven it??? you must be a pretty good engineer to be able to look at a picture and automatically know that it wont work, maybe i should hire you to design for me! why dont you take your car and wiggle the front wheels, guess what, there is more slop in the front end of your car than in my rear end. the front has bearing slop , dual tie rod slop and servo slop. but my .015 slop is waaaaaaay worse. its amazing that my chassis even makes it around the track its soooooo bad. and actually its my plan to fool everyone into buying my chassis so i can make a million dollars!!
gimme a break man, your only making yourself look bad By making statements like that when YOU DO NOT KNOW WHAT IT IS LIKE. it would be different if you actually had a chassis and it didnt work than you could make a point but this is not the case. so please do me a favor and save your negativity for another thread or wait til it is released and fails and you can be the first to say "i told you so".......

whats funny about all of this is that i have not created anything new, just combined what i feel are the best systems out there single ball pivot (proven to work) tri-shock (proven to work) dual link (f109 proven to work) but all of a sudden because of some black hole is space, every f109 on the plant all of a sudden quit working!!! last time i checked INZANE won every race last year in his series with a linked 109........but mine wont work???

for those of you that are positive and have sent me PM's , thank you for your support! the haters only pour fuel on the fire
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Old 11-21-2010, 08:44 AM   #66
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and you know this because you have driven it??? you must be a pretty good engineer to be able to look at a picture and automatically know that it wont work,
I make no comment about your car as I know nothing about it but show me a picture that allows me to see that the roll center will be a foot above the car and I WILL tell you it wont work very well. If there was no way to know if something should work or not on paper, there would be no engineers, there would be no paper. Trial and error backyard mechanics would rule the universe.
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Old 11-21-2010, 09:11 AM   #67
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I make no comment about your car as I know nothing about it but show me a picture that allows me to see that the roll center will be a foot above the car and I WILL tell you it wont work very well. If there was no way to know if something should work or not on paper, there would be no engineers, there would be no paper. Trial and error backyard mechanics would rule the universe.
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Old 11-21-2010, 10:39 AM   #68
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I make no comment about your car as I know nothing about it but show me a picture that allows me to see that the roll center will be a foot above the car and I WILL tell you it wont work very well. If there was no way to know if something should work or not on paper, there would be no engineers, there would be no paper. Trial and error backyard mechanics would rule the universe.

maybe i am crazy but show me how you change the rear roll center with only a single ball pivot point. if you can prove how that works enlighten all of us. my ball pivot is on the exact same plane as every other single ball pivot pan chassis out there the more i think about it the more i wonder what in the world you are talking about, you cannot change RC on a motor pod setup the wheels are always parallel with the ground and the pivot point is at its lowest point, the chassis itself can roll but the pod can not so in that sense the front suspension controls RC not the rear, now with a link system you can alter the IC. maybe you accidentaly got your terms backwards , at least i hope so!

exotec,f109,CRC etc etc they all have the same pivot point, but of course mine will not work because of the "desktop engineers association". send me a DXF file or post a diagram of how this will not work and how you have figured out how to eliminate ALL "slop" in RC cars. let the debate begin!
BRING IT, maybe you can teach me something, maybe not and while your at it show me what you have designed/fabricated that works.

oh yeah one more thing, explain to me why the f109 does not work again??

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Old 11-21-2010, 10:49 AM   #69
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Again, I was NOT talking about your car. Just pointing out that if you know what you're doing, you can tell a bad design from a photo.
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Old 11-21-2010, 10:51 AM   #70
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Originally Posted by Der Dicke View Post


The sprung mass rolls around the axis, that is given by the 2 pivotballs. The rc is on this axis, but behind the pivot balls (At the position of the rear wheels).
Great example. Really helps to show how it works.
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Old 11-21-2010, 10:59 AM   #71
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JMHO--but I am thrilled to see ANYONE working on F1 designs.
Bring one to Horsham and people will be ALL over it.
Better yet-- sell me one
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Old 11-21-2010, 11:35 AM   #72
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Again, I was NOT talking about your car. Just pointing out that if you know what you're doing, you can tell a bad design from a photo.

oh ok man, sorry about that, i have been getting hammered here lately and its getting old! my apologies
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Old 11-21-2010, 11:36 AM   #73
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Great example. Really helps to show how it works.
but this is two ball pivots, on my design the links make up for the missing front pivot and this is IC not RC.
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Old 11-21-2010, 11:49 AM   #74
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Originally Posted by heretic View Post
OK

Sorry to be so stubborn, but I just don't see how a Tbar car could have the roll center anywhere else than in the middle of the pivot ball - let's suppose it's horizontal for the sake of the discussion.
Quote:
Originally Posted by Der Dicke View Post


The sprung mass rolls around the axis, that is given by the 2 pivotballs. The rc is on this axis, but behind the pivot balls (At the position of the rear wheels).
Quote:
Originally Posted by MantisWorx View Post
but this is two ball pivots, on my design the links make up for the missing front pivot and this is IC not RC.
He was responding to someone that asked about a T-bar car.
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Old 11-21-2010, 01:06 PM   #75
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The sprung mass rolls around the axis, that is given by the 2 pivotballs. The rc is on this axis, but behind the pivot balls (At the position of the rear wheels).
OK, I see, thanks.

Mantisworx, I am not an engineer, of course, but I have seen and owned enough link cars to know that empirically it works perfectly...like the F109.

I think the only reason your car can make it around the track is because of the flex and slop of your links, to a larger extent than for the other link cars.

Excuse my less than average english, it's not my mother tongue.

Good luck.
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