Hi Fellow Summit Owners!
I just made the transition from RC Helis to RC Trucks and the Summit is my entry to this side of the RC hobby. While I was waiting for the Summit to arrive at my doorstep, I got a bit anxious to get it up and running right away when it arrived. I had two Dewalt XRP DC9096 18V NiCd packs (15 cells each) that I use for my impact wrench so I harvested the NiCd cells from one of them and made two 2500mah 7 cell packs and charged them up. As soon as the Summit arrived (and the UPS guy was a bit jealous and asked if I wanted to refuse the package... ) I soldered the additional Traxxas connectors I ordered on the NiCd packs, plugged them in on the truck and fired it up. And then I hit the throttle! Awesome!!!
After running these a few times, alternating between the stock PowerCell 7 cell 3000mah packs and the 2500mah Dewalt XRP NiCds, I'm getting longer runs and more power from the Dewalt NiCd packs. I guessing the NiCds have a lower impedance (they were used to remove lug nuts on my full size truck in their former life). These are Sanyo NC-2500SCR cells.
Yeah, I know NiCd is old school, but I thought it interesting that they seem to outperform the stock PowerCells. (3000mah NiMH vs 2500 mah NiCd).
This is an awesome truck and forum! Can't wait to get this thing upgraded to brushless and LiPo (when funds allow). I suppose I'll start with the Dewalt motor since I have an old 12V Dewalt drill laying around. Looking forward to lots of fun on this side of RC "land".
Welcome to the other side! The summit is awesome! (Just make sure you don't get it run over by a fullsize, then it's not quite as awesome!)
Interesting indeed that the NiCad is better. Are you getting the same speed/acceleration as the stock packs?
The forum is great, and the truck is great, you made some good choices!
I gots trucks and no idea what I'm doing!
i get excellent run times with my nicad packs with brushed motors and brushless as well. my run times with the brushed motor is like 30-38mins and on brushless motor around 20-25mins depending if i use full throttle alot. they can handle more power than what it is rated for i have found out on certain batteries
On a full charge with the NiCd pack, the Titan 775 screams (for lack of a better term) at a slightly higher pitch. This is likely due to less voltage drop on load. And yes, I do think speed/acceleration is slightly better on the NiCds. I know this is subjective at this point, so for fun I'll gather some hard data with my available tools. Per the Sanyo spec sheet, these cells are 4.5mΩ impedance (x7 = 31.5mΩ for the pack). I can't seem to find documented IR specs on the PowerCells, I'll run an IR measurement on them in a bit.
Man, good luck with your rebuild. I've gone as far as cleaning the thing and adjusting the suspension... and studying the parts list and diagrams. Daunting to say the least. But I guess that's why we're in this hobby. Bash it, break it, rebuild it, all while supporting the economy (and the LHS) at the same time...
i would run 14 volt dewalt---alot better than 12 volt---they are pretty cheap to get also---everyone says they are some torque monsters---ive got one just havent had time to put it in one yet---i got 3 summits total in house---wifes is bone stock---i got one with tekin 1700kv and other was powered by mmm---but its being run on stock setup at moment---it may get the dewalt or wait til my next one
???Why so serious???
does that new batteries no need to be cycled a few times to reach full potential.I suggest Lipo the difference is vast, but then again my nimhs was not very good either too much use i think for them
I just ran an IR measurement on the PowerCells. Comes to 10.5mΩ/cell (73.5mΩ/7 cell pack). So, the NiCds do have a lower IR, which means less voltage drop on load. I guess industrial grade cells are the way to go??
Will definitely go LiPo when I either get a LVC, LiPo alarm, or new ESC (eyeing the Tekin RX8). I may rip apart my Porter Cable 18v Lithium pack for kicks. (hopefully my power tools won't mind...)
Trax: you're probably correct. I'm doing a few forming charge cycles now.