T600 in a 42" hull, kv suggestion?

[iridebikes247]

I am building a 42" MRP Fountain the boat is like 20 years old, hull is in great shape and is very light. I am set on the Turnigy t600 motor (run two in an MHZ cat, the torque is brutal), and will be running on 4-5s.I have decided on:

3/16" flex shaft
Hobbyking vanquish rudder/strut
Turnigy 180A esc
Turnigy T600

The problem is I'm not sure of the KV rating for the motor. I run twin 1400s in the mhz, but should I run something lower since this is a big boat operating on a single(looking to keep heat low)? I really just want the boat to hit 30mph, the water is more often rough than not where I live so high speed runs never really work out too well anyway.

[iamandrew]

intersting, ill be doing something similar but with a 1700KV 5682 on a 98CM mono on 5S but starting to be unsure about it now

[lenny]

Hi,
I hear the 1400kv should be fine for that hull,
Just do not over prop it and it should run cool for a outrunner.
Hears some links on the motor and running in a 41" mono,
Very cool stuff. http://forums.offshoreelectrics.com/...tte-40-quot-6s

http://www.youtube.com/watch?v=59pVP7yTdPc&feature=BFa&list=UL59pVP7yTdPc&lf=mfu_in_order

http://www.youtube.com/watch?v=82XRhUAA3nM&feature=BFa&list=UL82XRhUAA3nM&lf=mfu_in_order

[keithbradley]

For your goals I would use the 1100kv on 5s, with something like a x455 prop.

In my 40" mono, I ran a Neu 2215 1090kv on 9s2p for ~70mph, but I did take it to one of the great lakes and ran it in pretty rough water on 6s and never got it close to WOT. It still seemed fast in rough water. It definitely went over 30mph, and I think yours will do 30mph+ with that setup (5s + 1100kv) as well. If you want to run 4s you should probably go with the 1400kv, but 4s is very low voltage for a hull that size.

[Make-a-Wake]

I actually have one..........and run it...................It is the lightest hull ever made to start with. It is narrow and will torque roll if you blow on it. My setup is a KB45(insert laugh) long story........1600kv and i run it on 5s with a T180 spinning an Octura x445. The 45mm prop is all i would ever throw on it...........it runs mid 30's with this setup which includes stinger and offset rudder, great old boat!

[keithbradley]

I actually have one..........and run it...................It is the lightest hull ever made to start with. It is narrow and will torque roll if you blow on it. My setup is a KB45(insert laugh) long story........1600kv and i run it on 5s with a T180 spinning an Octura x445. The 45mm prop is all i would ever throw on it...........it runs mid 30's with this setup which includes stinger and offset rudder, great old boat!

^^^Listen to this guy as he clearly knows better than the guy who posted above him!

In light of make a wake's experience with this hull, it looks like you would be much better off with the 1400kv motor as the larger prop may cause problems.

I would be curios to see the difference though, as spinning a prop faster creates torque roll just as spinning a larger prop does...

[Make-a-Wake]

^^^Listen to this guy as he clearly knows better than the guy who posted above him!

In light of make a wake's experience with this hull, it looks like you would be much better off with the 1400kv motor as the larger prop may cause problems.

I would be curios to see the difference though, as spinning a prop faster creates torque roll just as spinning a larger prop does...

I guess the spinning, laughing head emoticon is a sign of a light hearted response..................hope so anyways Keith. I have never really heard much about larger props vs smaller ones spinning faster and the torque effects............just seems to me that less diameter would be best. The hull is ABSURDLY light.................... and I added trim tabs to keep it from leaning so bad under acceleration especially. The keel lline is straight as an arrow from the transom til about 4 inches to the tip of the bow..............old school i guess, and i have a bit of positive in the stinger and batts back as far as they can go.

[keithbradley]

I guess the spinning, laughing head emoticon is a sign of a light hearted response..................hope so anyways Keith. I have never really heard much about larger props vs smaller ones spinning faster and the torque effects............just seems to me that less diameter would be best. The hull is ABSURDLY light.................... and I added trim tabs to keep it from leaning so bad under acceleration especially. The keel lline is straight as an arrow from the transom til about 4 inches to the tip of the bow..............old school i guess, and i have a bit of positive in the stinger and batts back as far as they can go.

Just saying you clearly know better in this situation than I do, given you own this hull. It wasn't sarcasm or anything other than giving you the respect you deserve. I am not familiar with his hull and you are so your opinion definitely carries more weight.

I boat will torque roll pretty badly even if you spin a little prop fast enough. My 32" cat with a m440 could literally flip if you nailed the throttle from a stop (~40,000rpm).
I think the smaller prop would most likely torque roll less in this case, like you said. I would be curious to see the difference though...just because I've never tried spinning a prop that slow.

[Make-a-Wake]

I hope the OP doesnt mind if i post a pic of mine since he hasnt shown off his cool hull yet.

This is mine as it came to me 3 years ago..................scored it on flea-bay, bit different paint scheme now

[gb tiggycat]

Hi Guys,

I have just started a similar build over here in the Uk. We have 2 nitro Offshore racing organisations, one mainly racing on the ocean (OMRA) and the one that I belong to (BMPRS) uses inland lakes. I raised an issue recently on another forum about using electric power within the racing program for those of us who do not have convenient water that allows nitro boats. Due to noise and environmental issues, this is quite common. To cut a long story short, BMPRS invited members to bring along electric boats to race meetings to run as a sort of demonstration to show what is possible and to formulate some form of racing rules if enough interest is shown. They are particularly interested in the older style of boats prevalent in the UK during 60/70's like Swordsman, Cigarette and Surfury etc rather than the latest models. They are even tentively suggesting making it the EV (electric vintage class) Some of these older boats should be very visually appealing.

I am starting off with a 40" Cigarette hull produced by Martin Eastwood in Blackpool ( martno1fan on this forum). I have one of his early production hulls which is a lovely piece of moulding. Currently the plan is to fit a T600 1400v motor on a watercooled mount, using a 3/16" flex through a strudder. The ESC is a Turnigy t180 along with 2 x 8400mah 3S lipos run in series. This gives 6S but the two batteries allow easier lateral balancing than one 6S cell

I have also ordered a pair of watercooled battery mounting plates from HK. Bit flash but they will look nice! I intend to start off running it on Graupner carbon filled props until I establish which is the best size for it, then invest in some Octura or Prather metal props. I suspect it will end up somewhere around x445/x645 or x447, we shall see.

Should be interesting.

[Chrisg81983]

You might want to run 6s 2p meaning two 6 cell's in parallel NOT in series just my opinion I found it is better to run 2 pack setups in larger hulls while it also produces longer run times

[Make-a-Wake]

This boat originally came with a 540 brushed motor...................yep, single 540, had room for two 6 cell nicads, and a mechanical speedo would add the second 6 cells for higher speed..............as i mentioned, the boat is light as a feather. 2p is not needed, I'm running 5s1p and it goes nicely.

[Make-a-Wake]

BTW, if anyone has an interest in one of these rare hulls..............here's one!!

http://www.ebay.com/itm/250984493995?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[iridebikes247]

Hey guys thanks for all of the replies I am definitely going with the t600/turnigy 180. I think I am going to run two 4S packs in parallel to keep the run time up. I am building this boat for someone else and basically he just wants something that runs at a scale speed through light to moderate chop. The hull really is ridiculously light, there are a few videos up on youtube of people running the boat on 6s, one with a Neu motor. I also have an ABC super hawaii and MRC Nordic Vee that I may build up soon.

[Make-a-Wake]

I also have an ABC super hawaii and MRC Nordic Vee that I may build up soon.

Thats a big coincidence! I'm building one of each right now!!!

Nordic: http://forums.offshoreelectrics.com/...ic!&highlight=

Hawaii: http://forums.offshoreelectrics.com/...s!!&highlight=