Propulsion system recommendations for large deep vee (55")

[fox88gt]

So here is my list of electronics and hardware that I’m looking at using for this hull:

2x Turnigy H600 3740size 1180 KV outrunners
2x Turnigy Aquasport 120A ESC
2x 6S Zippy 5000 MAH 40C LiPo
Octura X450/3 L&R
0.187 Flexshaft L&R
2x OSE drive dogs
2x Speedmaster stinger struts
Big ass rudder from OSE
2x OSE-80230 motor mounts
OSE-80925 trim tab set
Hi-torque servo
2x Octura 6mm to 0.187 drive collets
1x transom dual water pickup
4x aero-2011 water exits (replicating dual thru-transom exhaust on each engine)
3 feet of ¼” tubing
2x ¼” water line tees
2x 9/32 OSE stuffing tubes and Teflon liner for 0.187
2x OSE ¼” bulkhead fittings

I am open to suggestions on any of the above items! Thanks! Jeff

[fox88gt]

It sure got quiet in here! Anyone? Bueller, Bueller? You won't hurt my feelings if you don't agree with what I have listed! Have a great day everyone. Jeff

[gb tiggycat]

Hi Jeff,

Looking at the Hobbyking listing for these motors, they list max power for these motors as 11S. I presume that you were looking at running 6S ( either one lipo per motor or the two cells in parallel ?) Think that you may not get best performance that way. Also prop strikes me as being a bit ambitious for those motors.

I think that the Hobbyking T600 1100kv outrunners might be a better bet. These would give lots of torque on 6S. If it were mine, I would also use 180A esc's to give you a bit of headroom

http://www.hobbyking.com/hobbyking/s...i_1100kv_.html

An chum of mine who makes large Apache hulls commercially has a customer in Scandinavia running one of his 57" hulls on twin T600 ( might even be the 880kv version) giving a very fast and stable boat. Should be a video on the link below

http://www.waveridermouldings.zoomshare.com/6.html

Regards
Ian

[fox88gt]

Thanks for the input Ian, thats exactly the feedback I was looking for. You assumed correctly, I'm looking at using one 6S pack per system. Also, thats a good idea for the ESC's - hate to see one or both go up in smoke because I'm asking too much of them. Do you know what props that boat was running in the video? Thats pretty much exactly what I'm looking to achieve with this build, performance wise.

[gb tiggycat]

Hi Jeff,

I am not sure about the props, but I think they were x447's and were probably a pair of left/right pitch spinning opposite ways. I know that there are several other videos of this boat posted on youtube other than the ones on Martin's (waverider) site. I will try and drop him an email tonight and ask if he has more info as he is most helpful. He would probably have replied to you himself but he upset Steve a while ago and got banned from the forum!

I am currently finishing off one of his 40" Cigarette hulls . This has a single T600 1400kv motor, T180 esc and two 8400mah 40c 3S lipos wired in series to give 6s. This is driving through a Prestwich models 3/16" stinger with an offset rudder. I intend to try it initially with some of the Graupner carbon props to find the right size before investing in a metal prop, although I would be surprised if I didn't end up with a x447. Probably a bit overpowered, but it is quite a bulky hull and you can always throttle back whereas if underpowered it won't get used!

You might find this of interest as well

https://www.facebook.com/groups/347874658563715/permalink/687245104626667/#!/groups/347874658563715/

Regards

Ian

[gb tiggycat]

Hi Jeff,

Doing a bit of digging and found that Pate whose boat features in the videos is a member of this site and posts under the name of fastvee. Do a search and lots of info comes up about his Apache build. From another youtube I found , it would suggest that he is using 57mm props on it at present which strike me as large . Looking at one of the videos, think the motors he used was the 880kv version which would explain the prop size compared to my 1400kv thoughts



http://forums.offshoreelectrics.com/...hlight=fastvee

[lenny]

That is what I posted in post #16.

Hi Jeff,

Doing a bit of digging and found that Pate whose boat features in the videos is a member of this site and posts under the name of fastvee. Do a search and lots of info comes up about his Apache build. From another youtube I found , it would suggest that he is using 57mm props on it at present which strike me as large . Looking at one of the videos, think the motors he used was the 880kv version which would explain the prop size compared to my 1400kv thoughts



http://forums.offshoreelectrics.com/...hlight=fastvee

[iridebikes247]

Go 447s. X450/3 is a serious prop. Its like an x457 and those 120 amp escs won't like them at all. 447 start on 4s and see how it goes you might be surprised by how quick it is.

[fox88gt]

Hi guys,

After reviewing fastvee's build of the Navajo waverider, I'm going to stick with a similar setup to what he has done. I'm going to stick with packs with at least a 40C rating for this big girl though. I can't thank you all enough for the knowledge you all have shared.
I plan to start a thread on the build forum here once I get it started. Before I start that build though, I'm finishing a cosmetic restoration on my old Dumas Coast Guard boat. My dad and I built it in the late 80's, and it has 25 years of shelf wear, but everything is there and it should be very enjoyable to finish restoring it - I'm about 1/3 of the way done. I just need a new ESC and steering servo for it and I'll have a great rescue boat again. My dad did a great job with the running gear as it just passed an overnight float test in the bathtub with not a drop of water coming through the rudder shafts or stuffing boxes.

[iridebikes247]

nice dude good luck. the prop is everything and will make or break all electronics. 447s or even a 445 or something for starters should be good

[fox88gt]

Thanks man, I'll definately start small on the propeller size as I'm looking for runtime over all-out speed. Not that I want the boat to be slow, but a nice balance of speed and runtime. I may not get started on the Scarab until after the new year (gotta finish the rescue boat, and rebuild the carbs on my full size boat).