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Old 01-21-2008, 09:16 PM   #31
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Actually most of the link cars with the pack going across the chassis allready have long battery slots since they have adjustments to move the battery foward an back to shift the balance. They probably would be the easiest to convert. This is cars like the Gen X, Db12R, and others. The Darkside and Diggity with the in-line batteries would be a bit more difficult of a conversion as all new battery slots would need to be cut.

And that is all fine for the change over period to the new technology. But I imagine we would quickly see even more radical changes in chassis design to try and maximize the weight difference. Possibly even something so far out as the electronics toward the back (including the servo) to try and get some more weight on the rear and the batteries toward the front.
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Old 01-21-2008, 09:23 PM   #32
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Mason has a good point,

Just because you can abuse LifePO4 cells more than any other battery including NiCD you still need to be wise about your cell handling. Never overcharge, over discharge, leave batteries connected when not in use or try to attempt the vidoes shown on YouTube about the abuse these batteries take.

If you have a LiPO charger and would like to balance charge a LiFePO4 pack without spending another $100 to $200 for a charger there are things like the "Daptor" which should allow you to charge the A123 cells. Do some research before trying it, I just heard of the "Daptor" last week.
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Old 02-17-2008, 07:10 PM   #33
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I Saw something today that made me wish I had brought my camera with me to the track. One of the local guys, Roland Shao (hope I spelled that right, Roland) came out with something that really made me take notice. He took an old Diggity 1/12 chassis, put a two cell 7.4v LiPo in it, with a brushless 1/18 Mini-T motor in the pod and a Quark speed control (he had to fabricate a little adapter plate for the motor to fit, but it looked like an easy enough thing to make.) When he first showed it to me, it had the body on and it looked like your everyday normal 1/12 scale car. He handed it to me and said "that's ready to run", to which I replied "yeah, when you put a battery in it." That's when he turned it over and I could see what was going on.

My first reaction was that no way would it work well. The motor looked absolutely TINY in the pod (you could have fit three of them in there) and with the Diggity setup of the battery running longitudinally up the middle I expected it would simply be WAY too nose heavy to handle.

Then he did some laps. To make a long story short, it looked absolutely GREAT out there. Didn't put a stopwatch on it, but I'd bet money it would have been the class of the field against 19 turn cars, no doubt whatsoever it would have demolished the stock field. I drove it some, and I have to say it drove VERY well. Tire wear seemed a LOT less that we get now, I guess the reduced weight takes care of that, and the times I saw it test the integrity of the boards it took no damage at all (again, the lighter weight probably had something to do with it.

The only issue I could see was that it dumped after 6 minutes or so, but no one was driving to make run time... And this was with a 1500mah Lipo pack. And did I mention the thing was FAST with a capital F. I'd pretty much bet a paycheck that with a bit milder motor and a 2074 or 2200mah LiPo (which are pretty common among the TRex Heli guys) it would have made time easily and still given the 19 turn guys a hell of a run.

I'll be the first to admit that I tend to resist change, but seeing this car in action made a believer of me. Our track (360 Speedway) will run a class if 5 people show up. I'm going to prepare something to run, it just seemed like there was no downside to this... Faster, lighter, less tire wear, better crash survivability, and so on, and so on... Not that I'm ready to abandon 4 cell 1/12 scale... but I could DEFINITELY see myself running one of these as well. Heck, I'd want one if for no other reason than to have a super low maintenance practice car to run between race days.

I don't know if this is the future of 1/12 scale, but if it does go in this direction, I'm not in the least bit hesitant. If ANYONE would have told me yesterday I'd be saying this today I'd have told them they were outright crazy, but seeing IS believing.

Consider me a believer.
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Old 02-17-2008, 07:33 PM   #34
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Sounds cool Trips...that is pretty much what Slapmaster and I have been talking about doing. Though with the SCiB cells able to make a 4.8v pack I am thinking this is probably what we are going to see in the future. Personally though I like the 7.4v with smaller motor idea
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Old 02-17-2008, 10:32 PM   #35
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Quote:
Originally Posted by Trips
If ANYONE would have told me yesterday I'd be saying this today I'd have told them they were outright crazy, but seeing IS believing.

Consider me a believer.
Don't ask, I'm not giving you any lotto numbers.
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Old 02-18-2008, 07:24 AM   #36
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No!!!! this is the reason im trying 1/12 electric, because its simple and uses 540 motors!! lol Its the variety i love. If there was lipo, they wouldnt be allowed to lower the weight right? people would have to add weight, instead of the Ni-Mh/brushed guys trying to lose weight?
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Old 02-18-2008, 12:29 PM   #37
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Don't worry Ferrarimk, we are not talking about now...we are talking about the future of 1/12th when NiMh batteries are difficult to get in good quality race cells.
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Old 02-18-2008, 01:27 PM   #38
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I'm going to try some CR123A Li-Ion cells in 12th to see how they work. These cells are actually smaller than a sub-C cell so the only mod that would be needed is a simple lexan tray that would sit in the battery slots. I'll try both single and 2 cell voltages. Worst case, they'll probably fit into my Recoil. At $20 for 10 cells they're pretty reasonable.

I still think that the best thing would be to actually make a sub-C sized cell but...

I know that this thread is a look toward the future but I think that it's a good thing to capture where we're at now.

1) There are no Li-Ion/Fe04 cells available that even remotely fit in the package space of a 12th saddle pack.

2) The only cells that I've found that will fit into a saddle style 12th car would require a bunch of cells to handle the current that 12th draws. Cost of the pack that I built to test was around $100 for 12 cells.

3) Both LiPo and Li-Ion based cells can't make the voltage that we currently run in 12th (or oval).

4) The oval guys are using LiPo packs with high wind motors. They seem to be pretty happy with this combination (LiPo & 21.5).
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Old 02-18-2008, 01:53 PM   #39
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Quote:
Originally Posted by InspGadgt View Post
Don't worry Ferrarimk, we are not talking about now...we are talking about the future of 1/12th when NiMh batteries are difficult to get in good quality race cells.
phew I just dont see the need for such drastic changes whether that would be now, or in the future. Sure lipo and brushless will take over eventually, but ill promise you that they wont change motors to fit batteries, its never been that way, and i hope it never will. Until they find a 4.8v lipo, i aint switchin
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Old 02-18-2008, 06:11 PM   #40
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phew I just dont see the need for such drastic changes whether that would be now, or in the future. Sure lipo and brushless will take over eventually, but ill promise you that they wont change motors to fit batteries, its never been that way, and i hope it never will. Until they find a 4.8v lipo, i aint switchin
Well look back at how long it took NiCad to get phased out of racing when NiMh was legalized. Sure you can still get NiCad packs but those are all sport packs. Once NiMh was legalized the entire race manufacturing switched to NiMh in a relatively short time. Now the only class that LiPo is not legal in is 1/12th...how long will it be until the same happens with NiMh? Probably a bit longer then it did with NiCad because they are still being used in 1/12th but it will happen. So with current LiPo cells not being able to make 4.8v we are stuck with 3.7v or 7.4v choices (unless SCiB works out). With 3.7v it will be necessary, in most cases, to run a reciever pack 7.4v on the other hand is going to have a ton more power then we currently do so something needs to be done there to temper the power. The 2 choices is to change the wind specifications for each of the 1/12th classes or to change the motor entirely. Smaller motors have more then enough power in BL to power a car the sized of a 1/12th, are lighter, and take less space then a 540 motor. The lighter we can make the class the less wear and tear there will be and less damage in a crash.
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Old 02-25-2008, 09:01 AM   #41
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Well Roland had his experimental car out again yesterday, and Drew Smith brought one of his own as well. Roland ran in 1/12 stock with us to see how the car compared.

As I expected, it was the fastest car on the track, I believe it would have given a field of 19 turn cars a whipping as well.

Roland and Drew are both excited about this, I'm going to build one up for myself and see if we can't get this going as a separate class.

Roland's car is an old Darkside chassis, 2000mah 7.4 lipo down the middle, and a Castle 6800kv motor with a Quark 33A speedo. Drew's car is a Speedmerchant Rev4 (or 4.5, can't remember now) with the same motor and a Castle 25A speedo. I have an old CEFX chassis laying around that I might use, or I might build up a Speedmerchant version for myself.

Roland used a short piece of Carbon fiber tubing (1/8" OD) to adapt the pinions to the smaller motor shaft. Drew used a 48 pitch pinion that fit the smaller shaft directly. Both cars seemed to work very well.

I know my buddy Alex "Valls" has a spare Rev4.5 chassis in his box, I'm gonna start the brainwashing this week to see if I can't get him going with this too... Maybe we can have enough guys to run it as a "demo" class at the March 9 "Gauntlet" trophy race at 360 Speedway...
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Old 02-25-2008, 09:46 AM   #42
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Going with a new motor size isn't a really good idea as far as I'm concerned. I race 12th indoors and sedan outdoors and use the same motors all year.

If i'm forced to go with a new motor set-up I'll have to buy a new motor(s) and speed control. Add to that the cost of a LiPo and it's not all that great.

I did a little testing Sunday with a 17.5 and LiPo and it's pretty fast with 7.4v. Like almost mod fast. I didn't have enogh time to gear up at 3.7v so it was pretty slow. I was surprised to find that it ran fine on 3.7v without a receiver pack (spektrum system).
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Old 02-25-2008, 10:35 AM   #43
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Trips- Please post some pics. If you know anyone selling adapters for using the small motors please post that as well.

Here in Miami we have been racing Recoils at a really nice indoor facility. Thats all they race there but a few of us have gotten permission to run pan cars. Mind you none of us have ever run pan cars but we all have long admired the simplicity and beauty of the design.

Since we do have experience running 1/18 and 1/14 scale we are all very comfortable with Lipos and small brusless motors. I cant wait to run something that wont require a magnifying glass and girly hands.

I am buying a NIB genX from a friend and the A123 cells also sound very interesting. With my Hyperion charger which has programming for a123, I could charge them very quickly. With 2 packs I could probably run non-stop.

I dont know if this is the future but for our small group it looks like a way to get started and use alot of stuff we already have laying around.

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Old 02-26-2008, 07:35 PM   #44
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Ok do I have bad breath or something? lol.
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Old 02-26-2008, 11:29 PM   #45
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Trips- Please post some pics. If you know anyone selling adapters for using the small motors please post that as well.

Here in Miami we have been racing Recoils at a really nice indoor facility. Thats all they race there but a few of us have gotten permission to run pan cars. Mind you none of us have ever run pan cars but we all have long admired the simplicity and beauty of the design.

Since we do have experience running 1/18 and 1/14 scale we are all very comfortable with Lipos and small brusless motors. I cant wait to run something that wont require a magnifying glass and girly hands.


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