Lowering the centre of gravity….
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- This topic has 15 replies, 10 voices, and was last updated 21 years, 4 months ago by
brendan.
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September 21, 2003 at 6:06 pm #11367
Been thinking about this one for a while….
Want to be able to achieve the following
1) Stop the car from flipping on carpet.
2) Get better handling on floorboards.
3) Get some drifting happening, if possible.So I started stuffing around with some lead and I bashed a ball of it down into a plate of about 1.5mm thick. I then cut this plate to match the chassis profile from underneath. After this I then gave the lead multiple coats of clear gloss ’cause lead is poison and it can be absorbed through the skin.
As you can see it ain’t much to look at but it fits well. I use some bluetak to secure it to the base of the car. It ain’t a perm fix ’cause one needs access to the battery terminals for charging.
One idea though that has come to mind is that the lead helps to magnetically “insulate” the steering assembly from the ground and in my tests I’ve noticed that less crap gets caught in the steering. One place where I drive my cars has lots of metal filings on the ground that the car will just loose it’s steering with 20 seconds. The lead base plate has helped mitigate this.
As for clearance…..No problems there. I guess a full wheel mod would give you more clearance and allow a larger piece of lead to be positioned there….
So here it is, some video of a car with the lead plate. The car is a 45mhz chassis, mosfet mod with the perf 4.2Pro and 12:1 gearing. Rear tyres are lxx softs…
One thing I have noticed is a reduced runtime due to the increased load on the motor because of the lead plate. Increased load = increased current drain = decreased battery life.
Generaly I have now noticed better handling on floorboards. It might not seem the case from this video but before any motor above a 3.0 on my floorboards just ended up in torque spins all the time. I will do some more experimentation on this, increase the size of the lead plate, change the distribution of weight, etc, etc…..
ph2t.
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September 21, 2003 at 8:30 pm #32961
sounds like a good idea ph2t, might try it my self. maybe it will help my bit run in a strait line when i put a 3.0 motor in.
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September 21, 2003 at 8:31 pm #32962
i got a press n wi make some flat assss lead n c how that works
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September 21, 2003 at 8:41 pm #32963
I would reccomened a mosfet car for this, given the extra weight….
ph2t.
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September 22, 2003 at 5:41 pm #32897
does the mosfet increase output? if so a change to low ratio gears might also ruduce the strain on the motor.
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September 22, 2003 at 6:40 pm #32904
I’ve got the highest ratio gears on the thing, the light blue 12:1 ratio ones.
Wouldn’t the highest ratio gearing provide the motor with the lightest load? I’m not sure how a low ratio gearing would reduce load. Yes the fets increase the output torque of the motor.
ph2t.
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September 22, 2003 at 10:54 pm #32694
Something amiss here. I’m not sure if you’ve thought through the physics of it. How much does the lead weigh and how much more power do you require to accellerate the car up to speed.
Going around corners slower may be what is keeping you upright, not the lower C of G.
You can also lower your c’g by widening the wheel base etc. Good suspension also is what keeps cars from flipping. I’ve seen a few mentions of suspension on here before, but I haven’t taken any notice of what people have been doing (yet).Lead by the way isn’t really toxic. You exposure to it rather ‘minimal’ even swallowing it isn’t going to hurt you as it will pop out the other end without too much fuss. Compunds of lead on the other hand
are toxic. Lead chloride etc. Long exposure to such things or high doses will make you a bit dumber than the rest of us.
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September 23, 2003 at 6:59 am #32349
Depends how fast the lead is travelling 😛
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September 24, 2003 at 5:31 pm #32240
LOL good one!
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September 28, 2003 at 10:48 am #31346
I LIKE that vid and the MUSIC – what is it? Hendrix?
I notice that the car still gets into the occasional spin, though.
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September 28, 2003 at 12:25 pm #31348
Yeah the music is Hendrix, as always…:approve:
Yeah the car is still spinning out, not a much as before but still does. I just bashed another piece a lead that is longer and heavier now so I’m gonna give it a whirl soon to see how it goes.
ph2t.
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September 28, 2003 at 7:52 pm #31290
them low ratio gears would increase power output but lessen your top speed. since the thing is modded for power it would double the effect and wouldnt take as long to reach peak performance…
give it a go and tell us of your results….
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September 30, 2003 at 10:53 pm #39228
i done it but i must of done something wrong because it just slids out, it didnt make a differce if it did it made it worse, i just put some pull back wheels on ill give it ago see if it is any better.
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October 1, 2003 at 12:54 am #31064
I’m not sure what is available in tyre temprates like mini-Z, but maybe this is the answer.
Stock Z’s come with 50deg tyres… rock hard, they only stick to concrete. At the bottom end is
10deg, so soft that they practically stick to oilly carpet. -
October 4, 2003 at 5:27 pm #30511
I really need to get 12:1 gears. I’m running the same as you except I’m running 8.25:1 gearing. Your car looks way faster.
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October 4, 2003 at 7:43 pm #30514
Actually dude the 12:1 gears are slower than the gearing you state. :approve:
ph2t.
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