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View Full Version : My Blackjack 29 V3 progress



fweasel
10-23-2016, 02:57 PM
Got the boat from eBay with the sharpie mark of shame on the inside of the hull, but there was no damage, and even included the parts listed as missing in the auction description. Bonus for me. I initially installed an OSE flexshaft, OSE upgraded strut, and an Octura x642 S&B prop from RC Chief. Drilled out the cooling inlets and output, installed larger diameter cooling hose and routed it through the bottom of the motor first (shipped connected to top of the cooling can) and ran it on Turnigy Nano-tech 2S 5000mAh 35-70C batteries.

First run was a disappointing 36mph. My Blackjack 24 was running 34mph on 3S at the time
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Took it home, readjusted the strut, anad managed 38.3mph the following day.
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Video of the run
https://youtu.be/4P7tFgvabQM

Bigger issue at the time was a complete lack of range with the motor cutting out after a turn. I chased my tail on that issue for a while, replacing the transmitter (wanted a new one anyways), checking connectors, added a capacitor to the receiver, then finally replaced the receiver. It wasn't the new receiver that fixed the problem, but as soon as I pulled the old one out and compared it, the problem was very obvious...
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The non shielded part of the antenna had been broken off, leaving only shielded coaxial wire. Yep, that makes sens. Stripped back the shielding, added a little heat shrink, range issues gone.

Spent a little more time aligning the motor to the flexshaft, tweaked the strut a little more, and maxed out what I feel is the limit of 4S performance on this boat, 41mph.
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fweasel
10-23-2016, 02:58 PM
After several outings of reliable, trouble free runs at 4S, it seemed the boat was just to tame at that speed an had a lot left in it. 6S was the next step, and I had two new sets of graphene packs that I was running in the Voracity to try out. Not knowing where to start with the prop, I dropped down to a S&B stock prop that Dasboata did for me. Hull ran much drier, less bounce, and a good bump in speed. First run was 49.7mph
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Ran that setup for another two weekends while I figured out what prop to move up to and tuning my Voracity at the same time. Finally decided on an Octura x440/3 that I sent out to Dasboata. Came back looking like jewelry.
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Hurt my back this week, but felt good enough today to try out the new 3 blade prop. There would be no swimming today, so only the the red boat made the trip. Only other change I made for this run was to reroute the cooling lines to feed the ESC first, then the motor and dropped the ESC timing form 15* to 7.5*. Right out of the hole, the boat was screaming. Brought it back in after a minute, and the temps all seemed good. Ran it hard for the remaining 4min and just hit the LVC as I was rounding the last corner to bring it back. Opened the hatch, and a little bot of magic white smoke puffed out. Temps were pretty warm, 150*F on the motor, and nearly 200*F on the motor connectors, but the batteries and ESC were within range. None of the caps were puffed, no bad smells, not sure where the smoke came from. Maybe a little excess oil from the motor bearings? I let everything cool off while we ran the kids' boats. Best part, 59mph!
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Video of today's run. Boat runs very smooth on 6S with this new prop. No bouncing, tracks straight, can be a little squirrelly in the turns, but Rafael warned me of that and I'm hoping some strut adjustment might help.

https://youtu.be/xkRT5dXBNKM

I rerouted the cooling lines again to feed the motor first for the 2nd run. Sent it back out, ran great. Whatever smoked on the first run still had enough smoke left inside it that there were no problems. Forgot to start the GPS for the first half of the run. I brought he boat back in, temps were good, sent it back out again with the GPS running. Ran it hard, rolled it in a turn, but fortunately it landed business side down. Decided that was a good time to call it a day. Temps on the motor were still pretty warm, about 140*F, but the motor connectors were much cooler this run. Wondering if that was because I kept it out of LVC. Seems like whenever I run a boat back to shore on LVC from out in the middle of the pond, my temps are always a little north of where they usually are. GPS said 56.8mph, about 2mph slower, likely due to measuring the second half of the pack only.

Long story short, the 440/3 is an awesome prop for this boat on 6S.