THE RIPPER Rigger

[Ramtornado]

I have built this rigger Need suggestion about choosing a prop
it will run on one motor


what prop do i have choose whith the next Setup?

motor:
water jacket.
dimension: 63mm X 44mm
Shaft diameter: 5mm X length: 23mm
KV: 3300 rpm/v
voltage: 9.6V-18V
Electric Regulator: 45A
No load current: 5
Limited current (60/60s): 58
Max power (W/60S): 420

ESC:
http://www.hobbyking.com/hobbyking/s...idProduct=7341
converted to Water cooling

Hull:
Carbon coated HD foam
designed by me
weight-total 800 gram
length- 75cm
Those a 3 bladed prop will do OK ?
and what size should i go for ?

[NativePaul]

I will respond to this thread as it has some information in it, unfortunately there is not enough information, to get any prop recommendations you need to give us the voltage/cell count you will be using as well as the motor KV as 3300KV could be 2s 3s or 4s, and if someone recommends a 2s prop and your running 3 or 4 you will burn up your electronics fast. On the subject of your motor something doesn't ring true a 44x65mm motor outputting a maximum of 420W for 60 seconds, I would expect a decent 28x45mm motor to produce that all day long, also I expect a 44x65mm motor to weigh about 400g which is half the total weight of your boat, if thats how big it really is it may be a bit overboard and a smaller more efficient motor would be a worthwhile upgrade giving you more free weight for cells.

[Ramtornado]

thanks for the respond
i have 3s 30c 2800ma lipo and
and i will receive 4s 3700ma
the motor weights 300 grams with the connectors
quote:
something doesn't ring true a 44x65mm motor outputting a maximum of 420W for 60 seconds, I would expect a decent 28x45mm motor to produce that all day long

you mean that it should be more powerful then the say or the opposite ?
those that motor is over kill?

[NativePaul]

With 3s I would run a 35mm prop maybe upping to a cut 38 if all is well with the temperatures, on 4s I would start with a 30mm and slowly work up from there with extreme caution when you have the setup dialed it perfectly, that setup revs way faster than what most Americans race with, higher than most of us here in Europe race with too although not unheard of, at those RPMs any slight change to the setup or prop can alter the amp draw massively and burn stuff up so make sure you get a good set up before you try propping up and prop up one size at a time, I would have thought that eventually you will end up using a tongue cut 35mm.

All that assumes that theres something up with the stats for that motor though if you really are limited to 420w for 60s you would be more like 30-32mm on 3s and you can forget 4s.

44x65 is about the same size as a brushed can 700 motor and we were pushing over 500w through them for 5mins at a time I would expect MUCH more from any BL motor the same size no matter how badly made simply because it doesn't have tiny copper foil springs holding the brushes, 300g is also exceptionally light for a motor that size, as i said I would expect more like 400g, have you measured it yourself or are they quoted sizes? Could it actually be 36x65mm or even a 36x65 motor with built in water jacket that makes the OD 44mm? I guess an exceptionally inefficient Chinese 36/65 motor may only be able to handle 420W for 60 seconds, if when you run it on 3s with a small prop to start it still gets hot may I recommend you upgrade the motor even a relatively cheap 36x65 Feiago 540 9L will handle 900W for 5mins on 4s with the right prop, and its slightly lower KV more suited to 4s but still not too low for 3s with a bigger prop.

[Ramtornado]

i was running the 3300kv motor with 3S 2800ma with a 40mm prop i tried to run on 30mm
i had lot of splashes and no movement the prop was not effective at all i had water cavitation in the prop area maybe i had to change the angle of the prop but with 37 mm plastic prop its running faster then 40 with the same angel was good
the next video is the last video of the EXPERT II with different props

http://www.youtube.com/watch?v=b5a4b8KyhBc prop is 37
http://www.youtube.com/watch?v=r6MnAKhqq58 prop is 40

The hull is experimental so i have made several hull changes
and eventually i disassembled all the setup from that hull

The temperature of the motors was low after all my runs
i didn't check them with a thermometer but it was tolerable to hand touch

so what i understand from your post is not to use the 4s 3700ma on that motor??
i am all ready invested a a lot of $$$ in that motors
what do you recommend except upgrading the motors ?
i have received the 100A & 70A ESC from HK
http://www.hobbyking.com/hobbyking/s...dProduct=10015
http://www.hobbyking.com/hobbyking/s...idProduct=7341

i will convert them to water cooled and use them instead of my old 60A

Well i am new to boating only 3 years and all the stuff i know i learned from self testing and experimenting with different hull types and setups
My experience 15 years in the building and fling RC And Free flight gliders

I have 2 of 2600rpm/v
and 1 of 3300rpm/v the 3300 is lighter and shorter about 3mm then the 2600

[Ramtornado]

have more pics in my gallery
hear is the strut and rudder assembly

[NativePaul]

I would guess that the 3300KV with 37mm prop is over 420w but if it runs cool its fine just an underrated motor which makes a change.

The 2 submerged water pick ups just in front of the prop could be causing the cavitation on small props, you want the prop running in as clean water as you can that is pretty much the worst place you could put them and some may disagree but I don't see the need for submerged pick ups at all, an angled tube through the transom and hull bottom cut flish with the hull bottom, or a bent tube capturing some of the prop wash pick up enough water for my liking and have much less drag.

2600KV is a much better KV for 4s, start small and work up to 37mm if temps are OK.

Is this for an outrigger hydro, of for the mono in the pics and vids, if its for the mono you can discount all my advice, I don't know monos at all.

[Ramtornado]

all the setup configuration i tried was on the mono
now i want to put the same setup on my new rigger hull



i have anther problem with my 2600 motor the water jacket is clogged there is no water entering to the motor i received it like that i tried to disassemble the jacket with no success
i tried to heat the area to remove some how the jacket
do you have any clue on how to fix the problem?