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Old 10-30-2008, 09:04 PM   #301
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If I ran a t-bar car, I'd be tempted to wire a pack like that up in parallel and run one half on each side of the t-bar. Youd get a 9600 mAh 3.7 volt battery that would likely not need much if any weight to keep the car the same as it is with 4 NiMh. Can you say runtime? lol
Maybe I'm missing something though . . .
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Old 10-31-2008, 03:08 AM   #302
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Hi Danny

what testing has been done with mod motors? My motors of choice are 5.5t or 6.5t, would it be possible to run your lipo cell with these motors?

Steve
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Old 10-31-2008, 07:42 AM   #303
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Originally Posted by andrewdoherty View Post
If I ran a t-bar car, I'd be tempted to wire a pack like that up in parallel and run one half on each side of the t-bar. Youd get a 9600 mAh 3.7 volt battery that would likely not need much if any weight to keep the car the same as it is with 4 NiMh. Can you say runtime? lol
Maybe I'm missing something though . . .
I thought of doing the exact same thing with a T-Bar 1/10 pan car and an Orion 4800 saddle pack. The Orion's are hard-cased (required by some tracks) and you can mount both 3.7v "bricks" to keep the chassis balanced then just run your battery leads to which ever 3.7v "brick" you want to use and just switch the battery leads over to the other side rather than pulling out your battery to re-charge. I bet with 4800mah you could run two 5-minute (remember I'm running 1/10 World GT) races with each "brick" so there may be no charging what so ever if you run the usual 3 heats and a main. Also, you can charge both bricks at the same time as a 2-cell pack (maybe neccessary for those with lipo chargers that won't charge a single cell pack). Just a thought.
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Old 10-31-2008, 08:08 AM   #304
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Originally Posted by andrewdoherty View Post
If I ran a t-bar car, I'd be tempted to wire a pack like that up in parallel and run one half on each side of the t-bar. Youd get a 9600 mAh 3.7 volt battery that would likely not need much if any weight to keep the car the same as it is with 4 NiMh. Can you say runtime? lol
Maybe I'm missing something though . . .
Yes Andrew, weight. You are not going to want to lug around any extra weight running 3.7v. The weight limit at my track is going to be 680g for 1c Lipo. One of the main reasons for the whole Lipo deal was to make the cars very light to have less wear and tear, and tire wear. Also it's harder to make the 1c/13.5 run with 4cell/17.5 with out running light. Running light its right there.

-Donny
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Old 10-31-2008, 08:08 AM   #305
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... and just switch the battery leads over to the other side rather than pulling out your battery to re-charge.
The same tracks that require hard shell packs will more than likely require you to put the cells in a lipo sack for charging.
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Old 10-31-2008, 08:20 AM   #306
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Originally Posted by cla5675 View Post
I thought of doing the exact same thing with a T-Bar 1/10 pan car and an Orion 4800 saddle pack. The Orion's are hard-cased (required by some tracks) and you can mount both 3.7v "bricks" to keep the chassis balanced then just run your battery leads to which ever 3.7v "brick" you want to use and just switch the battery leads over to the other side rather than pulling out your battery to re-charge. I bet with 4800mah you could run two 5-minute (remember I'm running 1/10 World GT) races with each "brick" so there may be no charging what so ever if you run the usual 3 heats and a main. Also, you can charge both bricks at the same time as a 2-cell pack (maybe neccessary for those with lipo chargers that won't charge a single cell pack). Just a thought.

Thats essentially what I was pondering just with only one on the car, then saving the other side of the chassis for the reciever, ESC, PT, and reciever pack and any ballast thats needed.
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Old 10-31-2008, 08:30 AM   #307
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So what are the dimmensions of this SMC pack?
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Old 10-31-2008, 08:39 AM   #308
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Originally Posted by Danny/SMC View Post
The production pack with hardcase will measure L92mm x W46mm x H22mm.

The bottom does have some humps to fit in the battery slots but I'm not sure if the height of the bumps. I think they are 1.5mm but I don't see them dimensions on the drawing I have.
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Old 10-31-2008, 08:59 AM   #309
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Hi Danny

what testing has been done with mod motors? My motors of choice are 5.5t or 6.5t, would it be possible to run your lipo cell with these motors?

Steve
I've run some mod with single cell and it works fine. You do have to motor up 4.5 instead of 5.5 but it works fine. I even ran a 3.5 and it worked fine.

With the runtime that the SMC pack is going to have, you'll need to drive it oldschool to make it run 8 minutes but that's probably not a bad thing IMO
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Old 10-31-2008, 09:37 AM   #310
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I've run some mod with single cell and it works fine. You do have to motor up 4.5 instead of 5.5 but it works fine. I even ran a 3.5 and it worked fine.

With the runtime that the SMC pack is going to have, you'll need to drive it oldschool to make it run 8 minutes but that's probably not a bad thing IMO
Thanks Fred,

i do remember thoughs days when we had to drive carefully so as we didn't dump our cells at 6mins. I think i'll stick to the 4cell for the moment as it would hurt my championship hopes if i have to start backing off just so i could finish a race.

Cheers
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Old 10-31-2008, 09:47 AM   #311
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Originally Posted by Fred_B View Post
I've run some mod with single cell and it works fine. You do have to motor up 4.5 instead of 5.5 but it works fine. I even ran a 3.5 and it worked fine.

With the runtime that the SMC pack is going to have, you'll need to drive it oldschool to make it run 8 minutes but that's probably not a bad thing IMO
Sounds exciting, now (fuel) strategy can be brought back to racing. I thought it was long gone with the arrival of LiPO.

I'm sure the next generation packs will have a little more cacity to play with
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Old 10-31-2008, 04:29 PM   #312
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Yes Andrew, weight. You are not going to want to lug around any extra weight running 3.7v. The weight limit at my track is going to be 680g for 1c Lipo. One of the main reasons for the whole Lipo deal was to make the cars very light to have less wear and tear, and tire wear. Also it's harder to make the 1c/13.5 run with 4cell/17.5 with out running light. Running light its right there.

-Donny
Good point. I'm all for less tire and mechanical wear. I think our track is ripe for Lipo. Its nice to have some other data from a respectable source to stand on when presenting the idea. . .thanks for being honest and making your testing info public. These days it can get a little hairy when the words lipo and 12th scale are mentioned. If you don't mention the right number of cells along with those two words you might get crucified!
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Old 11-01-2008, 03:18 PM   #313
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So today I went to my old stomping ground for racing, and checked out what everyone was running. They all are running 17.5T 4 cell NiMH brushless setups on link cars. (in stock class) So I figure... if thats how it is... thats how it is I may just need to man up and buy a link car.

I got to talking to the folks about LiPo and everyone seemed to think 1S wont work as none of the ESC's are rated to work at that low of a voltage and could shut off mid run.

I know there was some discussion in this many page thread already about this. I was looking at a Novak GTB 4cell Spread Spectrum ESC with a 13.5 motor. Not sure thats the best choice or not in regard to the low V cut off.
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Old 11-01-2008, 11:39 PM   #314
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I got to talking to the folks about LiPo and everyone seemed to think 1S wont work as none of the ESC's are rated to work at that low of a voltage and could shut off mid run.

I know there was some discussion in this many page thread already about this. I was looking at a Novak GTB 4cell Spread Spectrum ESC with a 13.5 motor. Not sure thats the best choice or not in regard to the low V cut off.
I belive all that is needed for most ESC's is just use an RX battery pack with a switch. Leave the ESC switch off and only use the RX battery switch to power on the car.

For the GTB, you can turn off the low voltage cutoff. The instructions are at http://teamnovak.com/download/instru.../56-lipo-2.pdf
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Old 11-02-2008, 12:03 AM   #315
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Danny,

I don't know how bigh your influence is but I was thinking if 3.7V LiPO is going to get the green flag I would like to see two standards of battery packs legal for 1:12 cars. I would like to see ROAR commit to some provisional rules during this development stage so that if other manufactures enter the 3.7V market, they won't be making some odd ball sized pack or making a MEGA pack that is 50mm tall and that will just end up creating confusion and costing racers or manufactures extra money should one pack be illegal in future. These provisional rules would be more intended as guidelines to manufactures to provide club racers a LiPO pack for pan cars so IF 3.7V should become sanctioned, racers already have the legal gear.


Just an idea.
Pack Option for Linked Cars. 92mm x 47mm x 23mm MAx no +/- tollerance
Pack Option for T-plate cars. 70mm x 47mm x 30mm. MAX no +/- tollerance

When the outer skin is accounted for both packs should have roughly the same internal volume of battery so they should be equal. For T-plate cars this would require the battery to be placed on one sided of the T-plate and the ESC, RX and some ballast on the servo side. For linked cars, the provisional rules would keep the pack height low enough that the center shock can clear or will clear with a small spacer. Both packs would not require new cars but the T-Plate would fare better with the old school 6-cell layouts.
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