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ozzie-crawl
05-09-2013, 06:29 AM
getting back into boats after a few years of. Never had a rtr so orded a bj29 should be here tomorrow.
Going to run 6s with a proboat 1500kv motor.
Question is those who have run 6s does the bec in the esc handle the voltage or are you using a ubec.
Any input much appreciated.

Ozzie

G-UNIT
05-09-2013, 08:03 AM
Use a ubec or battery pack and disconnect the red wire, don't take a chance of burning up the esc, buy the way what esc are you useing, the stock one, if so upgrade to a t180 or seaking 180 JMO.
just maybe stick with 4s untill you get used to boating again and check out the bj section on here.

ozzie-crawl
05-09-2013, 08:40 AM
Thanks for the reply. Will try a ubec with the stock esc if it goes pop will try a t180.
I will try and data log the first few very short runs see what sort of amps it draws.

G-UNIT
05-09-2013, 08:47 AM
Good idea, I don't have a data logger so no good info from me, I just check temps and run times.
burned up to many esc when I started out and now I try and stay conservative.
have fun.

ozzie-crawl
05-09-2013, 08:57 AM
When i first started in boats a few years back i went threw countless esc,s. Very steep learning curve with boats.
Will definatley start of with very short 1-2 passes on 6s and see how it goes.
Thanks again for your help.

BHChieftain
05-09-2013, 09:37 AM
You probably know this, but just in case...
The blackjack has an 1800 motor in there while the geico has the 1500

Chief

ozzie-crawl
05-09-2013, 06:35 PM
Thanks chief. Have the 1500kv coming for it.
if i get the blue dynamite one are tbey the same as the older black can bj26 motor.
Picture of motor when i orded shows the old black can and i know they handle 6s from past experiance.
Not sure if the new blue can is the same motor with a face lift.

hydro_pyro
05-09-2013, 09:56 PM
Leave it alone and don't mess with it. Theres no need to swap anything out unless you plan to upgrade both the motor and ESC at the same time. Horizon presently sells this boat as "6s ready", straight from the horse's mouth. Don't believe me? Call Horizon and ask.

Just keep the stock prop and raise the strut nice and high so the prop is not overloaded.

I usually run mine all on 6s, all-bone-stock with a balanced and sharpened stock prop. The motor and wire connectors get fairly hot after hard running, but nothing has burned up. Consistently runs 50-60 mph.

ozzie-crawl
05-09-2013, 11:00 PM
I have 5.5mm bullets to put on and 1500kv motor should be here any day now. Would rather the lower kv on 6s.

hydro_pyro
05-10-2013, 12:00 PM
I measured running RPM on 6s with the stock motor at 31,000 to 34,000 RPM using audio tone and an average of approaching and departing Doppler effect.

G-UNIT
05-10-2013, 12:41 PM
According to the voltage chart your rpm would be 33,300. but is'ent that an unloaded rpm?

hydro_pyro
05-10-2013, 01:28 PM
When it's hanging nice and high on 6s, there ain't much load on it. :)

ozzie-crawl
05-10-2013, 06:35 PM
To me the 1800kv is a 4-5s motor. The 1500kv motor on 6s gives the same (unloaded) rpm as the 1800 on 5s but should have more torque and draw a bit less amperage.

hydro_pyro
05-10-2013, 10:23 PM
I'm sure we all know better than the engineers Horizon pays to design these things.

lenny
05-11-2013, 12:11 AM
I have my Mystic running on 4s in parallel with a 2364kv motor and SK180a esc and a modded m445 prop,
It is doing 54mph gps with a Garmin Legend on some old cells and everything is below 110f and the wires are 96f.
We will see what it does with some fresh packs I just got,
I also have some genace 4s 30c 5300mah I need to mod to fit in the hull some how now.:noidea:

ozzie-crawl
05-11-2013, 01:01 AM
I will try the 6s setup if it fails i have a couple of nue 1515 1y motors sitting here and some 4s packs.

champion221elite
07-19-2013, 04:23 PM
As a BJ 29 owner, I can testify the factory equipped 1800 kv is too hot for running 6s. It lacks torque, and is prone to excessive heat build-up after even a short 90 second run. The wires however are a major choke point. A 90 second run heats my motor to 130-135 degrees and the wires were literally smoking at 270 degrees. Horizon Hobby actually replaced my original motor after I called and told them what it was doing.

hydro_pyro
07-19-2013, 05:50 PM
I think prop balancing is a big factor. Grease choice may also play a role. I run a stock balanced prop and AliSyn TriboLube-12 grease, and I run back-to-back wide open passes on 6s until my packs are at 3.85 per cell. It gets plenty hot, but not hot enough to cook anything.

Take a stock boat on 6s with the propeller too deep and out of balance, with pig-snot-thick shaft grease, and one bad connector... Then you'll have problems.

angrycat
07-20-2013, 10:50 AM
As a BJ 29 owner, I can testify the factory equipped 1800 kv is too hot for running 6s. It lacks torque, and is prone to excessive heat build-up after even a short 90 second run. The wires however are a major choke point. A 90 second run heats my motor to 130-135 degrees and the wires were literally smoking at 270 degrees. Horizon Hobby actually replaced my original motor after I called and told them what it was doing.
i have done nothing but run 6s on this boat (i only have 3s packs) and i also ran into the same issue, nothing i changed besides drastic prop sizes would bring temps down on the stock motor. the 6 pole is perfect for 4s and will run on 6s but usually not without any issues. typical motor temps with upgraded cooling/5.5 motor bullet connectors and ec5 batt connectors after 2-5 mins was 130-150 and that was with an m440 prop which has less pitch than the stock prop. my esc went first after about 3 weeks of just about every day use and pushing it hard while trying different props and trying to get the boat dialed in. the motor just recently went on me and it was a wire that frayed broke off inside the motor can. i am now running a seaking 130a hv esc and a turnigy sk3 1900kv with an m440 prop and i can run the batts all the way through without motor temps exceeding 135-140 and keeping everything els at just about 90-100 deg. also these hulls scrub alot of speed in turns without blueprinting the bottom so staying on plane in the turns to help keep heavy load and amp draw down is also a major key in keeping the boat running cool. i was honestly surprised how well the stock parts held up after lots of trial and error and re-learning FE boats since im used to building rc cars

champion221elite
07-20-2013, 11:29 AM
I have already upgraded the esc discharge leads to 5.5 mm bullets since that how my 3s inventory is setup anyways. The 80 amp esc has so far stayed nice and cool. Temps have yet to exceed 95 degrees. The 1800 kv, 6 pole motor however runs far too hot for my liking.

I took Diesels advice and ordered a 1500 kv motor and will be turning a thinned/ sharpened/ balanced X442 prop. I'm hoping the lower kv motor and better prop will reduce my amp draw and solve the heat issues for good.

angrycat
07-20-2013, 11:37 AM
my esc also never saw any temps over 95 but it did see a lot of abuse. i was going to buy the pb 1500kv motor but i had found a deal on sk3 motors at the time and went 4 pole instead which imo is better for 6s boats since they see high rpms and rarely need the grunt of the 6 pole which is inefficient at high rpm comparatively. looking forward to see how you like the 1500 motor on 6s compared to the 1800

champion221elite
07-20-2013, 11:41 AM
It should arrive early next week. Just waiting to install the motor and prop. I have thinned and sharpened the factory stainless prop, but don't have a balancer yet. I'll post an update after I get a chance to run it.

angrycat
07-20-2013, 11:57 AM
thinning a stainless prop?? that must have taken some time haha

hydro_pyro
07-20-2013, 02:40 PM
It takes some effort, but I thinned down my stock prop too, and thinned some more to help get it balanced. If I remember right, it's a couple grams lighter than a stock casting, smooth and sharp.

champion221elite
07-20-2013, 03:00 PM
It took a few hours and a good portion of my bottle of Jamesons, but I got it done. I will try the stock prop with the new motor and see how it runs compared with the X442. I also have an X448 and Y547, but I think those may be a bit too much prop.

angrycat
07-20-2013, 07:34 PM
yeah i would believe that anything more than a x442 is going to really heat that stock motor up. maybe a s&b/t&p and DE-tongued x642 but the magic number on 6s seems to be 40mm or 42mm highly modified. i am currently running an m440 which has the same dia. as stock but the m440 has 2.1 mm pitch while the stock one has 2.5 mm

angrycat
07-20-2013, 07:36 PM
and did you guys just wet sand to thin it out or file it down then wet sand smooth?

hydro_pyro
07-20-2013, 08:06 PM
Working mostly on the back side, not the thrust face...

220 sanding disc on a Dremel, followed by an abrasive-impregnated soft gray tripoli wheel on a Dremel, followed by wax compound on a small felt buff wheel.

Thrust face work was limited to smoothing out the rough-cast surface and polishing it. It's very important to stay off the squared-off trailing edge in particular while sanding and polishing. I mounted my prop in a home-made jig and ran a diamond-grit file over the flat trailing edge to square it clean and sharp, as a final step.

http://i48.tinypic.com/2vcgbk4.jpg

http://i46.tinypic.com/x1x6cp.jpg

http://i48.tinypic.com/25plj82.jpg

angrycat
07-20-2013, 08:47 PM
very nice, lots of elbow grease applied there

champion221elite
07-20-2013, 08:49 PM
Hydro_Pyro wins. Mine is nowhere near that shiny... yet.

champion221elite
07-23-2013, 02:17 PM
Update for anyone who cares... the new PB1500/ Miss Geico motor and X442 showed up yesterday.

Diesel was absolutly accurate when suggesting this combo for the BJ29 on 6s. That little PB1500 is a beast of a motor, and is what Pro Boat should have equipped the BJ 29 with for running 6s. Motor temps are down, the wires aren't getting nearly as warm, and the esc barely gets over 85 degrees. Throttle response is soooooo much smoother. Overall, the motor swap and prop upgrade have completely changed the BJ29 into something even better.

BHChieftain
07-24-2013, 08:55 AM
I think keeping the RPMs under 35K is a wise choice...
If your ESC eventually dies, replace it with a seaking 180A and you'll have a bulletproof setup. What will kill your 80A ESC on 6S is a hop out of the water when the prop unloads and then reloads on entry and your peak amps go thru the roof. A higher rated ESC can absorb that much better.
Chief

champion221elite
07-24-2013, 09:12 AM
I think keeping the RPMs under 35K is a wise choice...
If your ESC eventually dies, replace it with a seaking 180A and you'll have a bulletproof setup. What will kill your 80A ESC on 6S is a hop out of the water when the prop unloads and then reloads on entry and your peak amps go thru the roof. A higher rated ESC can absorb that much better.
Chief

I already planned on replacing the factory 80a esc with an SK 180 when the original let's go.

My Sprint Cat has a SK 180 v2 in in already. I will likely swap that to the BJ29 and will get an updated SK 180 v3 for the Sprint Cat. The larger esc would give me plenty of head room if I upgrade the PB1500 motor to a Leo 3674 in the future.

BHChieftain
07-24-2013, 09:54 AM
I should clarify that if you keep the prop size down, then you should be fine... I think x442 is a good choice. If you move to x642 or m445 on 6S then you might be pushing it.

Chief

angrycat
07-30-2013, 11:59 AM
I already planned on replacing the factory 80a esc with an SK 180 when the original let's go.

My Sprint Cat has a SK 180 v2 in in already. I will likely swap that to the BJ29 and will get an updated SK 180 v3 for the Sprint Cat. The larger esc would give me plenty of head room if I upgrade the PB1500 motor to a Leo 3674 in the future.

sorry to ruin your day but there is no "version 3" of the sk 180a..... there was the origonal and the v2 with a better cap bank, some companies sell the sk180a with added cap banks but thats just an option not a new model

champion221elite
07-30-2013, 12:19 PM
It may just come down to semantics, but OSE is referring to the SK 180 with added cap bank as a version 3.

See linky...

http://www.offshoreelectrics.com/proddetail.php?prod=ker-seaking-180

squirrly
05-25-2014, 02:14 PM
I run my bj29 on 6 cell all the time and run about 6-7 mins. With EC5 and 6.5 bullets. Besides that Everything stock. But i do have the new upgraded motor with 12g wires. But i also dont hold it wide open the whole time either. And never had an issue. :)

tlandauer
05-25-2014, 03:05 PM
Kintec says :" there is no such thing as V3"---although you won't see it any more on Kintec's site, it is updated---- this ESC is DISCONTINUED!
Anyway, Both OSE and Kintec has a point: There was the original one, then Seaking put V2 on the label. When the "Factory" Cap bank came out Seaking did not make a new label as V3, but obviously one could consider it as yet another newer version.