TWIN ELECTRIC SGX RIGGER

[speakerboy]

He Dave ,

i ment that the strutt's are looking good and i was suprized to see how close they are together .

i am thinking of the same setup , i have a light built 4 inch wide gasrigger here from Twister marine (the netherlands) and it looks good enough to go for a electro twin .. why did you choose for the 1527 motors .. i am not looking for Saw speed and i wonder if i could go for the 1521 motors , if i can do 60 till 70 mph in heat race that will be fine. .

since my tub is 4 inch wide i wonder if i should go with the rudder all the way to the right side ore get the drives as far apart as i can and place the rudder in the middle ..

do you use 3/16 flex cable ore 1/4 flex ?

i will make pics of the rigger i have here , may be you can point me in the right direction ...

Jeroen

 

[David Kingston]

the tub on the SGX is 5inch.

I went with the 1527 for the torque and i can swing big props.

I have got a few 1521's and i dont think i could even attempt to have it running as well as it is on those motors.

I run 1521's in my 4s stuff and 5-6s is 1527's

Im only using 3/16th shafts but i can change to 1/4 at any time really.

The struts are to the correct width as per the instructions that were given to me from CMDi for the hull.

I cannot wait to test these other props i have though

Dave

 

[Steve-O]

Dave,

Very nice work! I love a nice clean build and when it performs well that's even better!

You did a super job! Now go break some records.

Steve-O

 

[David Kingston]

IT GOES HARD WITH THE 1462's that are pitched up.

Little hard on the cells though. If it was a 2p setup then it would be bit better. Motor and ESC come in a 100degF all the time. Cells with are up to the 120-130s now.

I really need to get test more to get the sweet spot.

Might try some different motors also.

 

[Andy Brown]

IT GOES HARD WITH THE 1462's that are pitched up.

Little hard on the cells though. If it was a 2p setup then it would be bit better. Motor and ESC come in a 100degF all the time. Cells with are up to the 120-130s now.

I really need to get test more to get the sweet spot.

Might try some different motors also.

David,

Awesome job on the build!!

To get the most out of your elecric power try to avoid any prop cupping. Added cup is not as beneficial to electric as it is to nitro/gas.

From what I've read here, start with a pair of 1465 and cut them to 60 mm and narrow the blades mostly from the leading edge. Back cut a little. Do not barr cut. Be sure to thin them good too as the 1465's will be very thick at 60 mm. If they are not enough prop at that point I would try stock 2160's.

The high revving motors with small props would be a good idea.

Good boating,

Andy

 

[David Kingston]

Andy

Thanks for that tip.

I will look into it

At current im pulling 27K before load on the motors. So that would drop to about 23K under load. Its The boat is reving nicely, but i might test another set of motors soon, that are not as amp hungry, but still keeping my RPM to the 24K mark.

I wish i had a video of the latest run wit the 1462's as that was going well. I have a H30s that i will try soon. Some H45, H50s Getting a bit big for the motors i have but there will be more to test soon.

Not to fussed if it takes me 6months to get it going better and better each time. Its part of the fun, tinkering and testing till you get it right.

When can you send me a 67 hull...

Dave

 

[Andy Brown]

Andy

Thanks for that tip.

I will look into it

At current im pulling 27K before load on the motors. So that would drop to about 23K under load. Its The boat is reving nicely, but i might test another set of motors soon, that are not as amp hungry, but still keeping my RPM to the 24K mark.

I wish i had a video of the latest run wit the 1462's as that was going well. I have a H30s that i will try soon. Some H45, H50s Getting a bit big for the motors i have but there will be more to test soon.

Not to fussed if it takes me 6months to get it going better and better each time. Its part of the fun, tinkering and testing till you get it right.

When can you send me a 67 hull...

Dave

David,

We'll be looking forward to more vids as you progress. If the H-30's prove to be a bit big, trim them down a little. Definately stay away from the H-45. They have huge cup (7.0" and will suck amps without giving speed. And yes H-50's might be a tad big too unless you cut them alot.

I almost forgot! V962/3 might be the ticket. They are easy to pull for the amount of pitch they provide. Try them stock. Your SGX-2 should handle nicely with them.

67 hull for Electric?

We could get one out fairly quickly. For Nitro .67 we have in stock ready to ship.

Good boating,

Andy

 

[aaron alberico]

Andy

I have been doing Dave's propellers,

the H30's i did for him are stock cup and around 60mm dia,

Dave is running a high torque set up,

Andy problem with V962/3 will be torque steer, as this boat is for oval racing,

it will pull it hard right, but yes V962/3 props would be awesome,

regards Aaron

 

[Andy Brown]

Andy

I have been doing Dave's propellers,

the H30's i did for him are stock cup and around 60mm dia,

Dave is running a high torque set up,

Andy problem with V962/3 will be torque steer, as this boat is for oval racing,

it will pull it hard right, but yes V962/3 props would be awesome,

regards Aaron

Aaron,

I don't think the V962/3's will have the torque steer problem that we have with the nitro boats because the power delivery is much smoother. We run the V967/3, 2167/3 and 2170 on the Gas SGX boats for heat racing and they work perfectly.....the same reason, because the gas power does not give the Hard Hit like nitro does. Give them a try. The V962/3 should be good for 80+ mph @ 23,000 rpm. If they are too big, trim them a little or try the V955/3 or the 2160. The struts must be raised maybe 2mm for all of those props, because they do want to run higher on the tips than 1400/1600 props. If you don't raise them compared to the strut setting for the 1400/1600 props it will also contribute to Torque steer.

Good boating,

Andy

 

[David Kingston]

Ive tried some 1460 props pitched to 5.0inch pitch. CMDI ones that i got second hand here in IW. When i tested those i had massive torque steer. If i was motoring at 1/2 throttle and hit full throttle the boat would pull from lane 8 to lane one in about 10 meters. Only could counter act it with full left rudder. Was average on speed also. Found that a pair of 1657's worked better.

Talking heaps to Aaron, he did up 2 sets of props for me. Unfortunatly last test day i only put 1657s out there for one run and then left the strut setup the same to test the 1462s worked. The temps were only up a bit with these props considering the size difference. Running the larger prop did unload the ass of it a bit more. Im hanging out for next weekend when i will make sure i have the camera with me for more video.

I wouldnt be able to pull the v962/3 on the current motors i have as i would cook something. Cells most likely. If i was able to run 2p, here in Aus (cannot cause of the rules) I wouldnt have an issue proping up even more. The only thing that is getting warm is the cells. The future is looking better and better with more capacity and lighter cells.

Any how there are a few small things that i need to attend to on the boat before it hits the water again. Got to stop the little bit of water thats getting into the hull via the shaft. Look at cutting the rudder down a bit. Still heaps longer than the plans for the SGX suggest. (what do you normally set yours to Andy)

Any how, enjoying this boat, and the challange.

I'll be in touch with that 67 hull.

Regards

Dave

 

[raptor347]

To get the most out of your elecric power try to avoid any prop cupping. Added cup is not as beneficial to electric as it is to nitro/gas.

Andy,

I don't want to start a big argument, but I have to disagree with you on cupping props for FE. I've found the FE systems respond even better to cup changes than gas/nitro. The tuning indicators are different as well as the limits of how far you can go with it, but that's no big suprise. Added cup does have more effect on handling with FE power due mostly to the torque curve and instant delivery.

Just my take on it.

 

[David Kingston]

Andy,

What props do people usually run on their twin 80/90 SGX riggers.

Assuming a mac84 or a pair of 91's in it.

I would have thought 1667's (about that size with work) - perhaps some ABC 21_ _ series props.

Thanks heaps

Dave

 

[Andy Brown]

Andy,

What props do people usually run on their twin 80/90 SGX riggers.

Assuming a mac84 or a pair of 91's in it.

I would have thought 1667's (about that size with work) - perhaps some ABC 21_ _ series props.

Thanks heaps

Dave

Dave,

Yes the 1667's are the good all around prop. Cut to 63 or 64 mm for the smaller power and full blade for the 90's. Cup any where from 5.4" to 6.4"

You mentioned torque steer with 1460's cupped 5.0"? I think there is a boat set up issue.

Which I also detected in your video. We need to get that cleared up before we can get the really fast props working.

 

[David Kingston]

Andy

Definatly when i tested the 1460s with 5inch there was some setup issues.

The video is with the 1657's and i was still tweaking with struts and AOT.

Since that video i have managed to get the boat to track straight and it rides on the sponsons and prop tips. Before you could just see it riding on the rear shoes, now the rear shoes are out of the water at full song. It doesnt have the hook in the turns, and the darting like it use to. Turned the steering down and the throw on the rudder.

Like i said, its getting better and better each time i test. I just wish i could test it more often.

I will get someone to take a video of the next run thats for sure.

Im kind of flying a bit blind being the first electric twin SGX but I'll get there adventually.

Dave

 

[Andy Brown]

Andy

Definatly when i tested the 1460s with 5inch there was some setup issues.

The video is with the 1657's and i was still tweaking with struts and AOT.

Since that video i have managed to get the boat to track straight and it rides on the sponsons and prop tips. Before you could just see it riding on the rear shoes, now the rear shoes are out of the water at full song. It doesnt have the hook in the turns, and the darting like it use to. Turned the steering down and the throw on the rudder.

Like i said, its getting better and better each time i test. I just wish i could test it more often.

I will get someone to take a video of the next run thats for sure.

Im kind of flying a bit blind being the first electric twin SGX but I'll get there adventually.

Dave

Sounds good Dave! Looking forward to seeing video of the latest set up. Yes that is the first eletric twin SGX, so you are flying a little blind. Be sure your right front sponson tip is running about .100" to .125" higher than the left sponson tip. Also set the left srtut about 1/3 degree flater than the right strut and make sure the turn fin break lines are running slightly down hill toward the rear. Also get the front end running as light as possible.

Andy

 

[David Kingston]

Bringing up an old post cause I found a video...

You tube search - EC hydro.

Latest video of my sgx electric twin

(if I had ability to copy paste I'd put link in but cannot with phone)

Any how this was its fist ever race. Before this it had never run against another boat of it's class but had run rings around a 67rigger so I knew it was quick, but was it race quick.

Never put my larger worked props on. I know it's faster with them but it was racing well and I didn't want to change.

Hull is getting a little make over now.

Should be ready to rock again in a few weeks.

Dave

 

[hugh hargett]

David why did you not like the castle esc's? What model were you running?

Nice vessel

Hugh

 

[RodneyPierce]

Here is the video for you David:

 

[Andy Brown]

Good driving there Dave! The boat is looking good on the bouys!

 

[David Kingston]

I had no luck with castle - plug and Burn. They were the HV240s. Glad I sold then and made my $ back

I have 2x 40/160s in there and they are plug and play. They don't let me down and it gives you confidence knowing the boat will start and if I don't crash, finish.

I would like to get a smaller Esc and replace the 40/160s. Was thinking fighter cat as a mate of mine has had good success with one. Survived a lipo explosion in boat and still worked. But FC Esc are not in business.

My goal for it is sub minute - 55 seconds in oval trim. Possible. I do have a pair of faster props which I know make the distance without hurting cells. The setup needs a little adjustment. Front rides light but I did get comment it looked like it was dragging its bum.

The boat really is a point and shoot, keeping wide open throttle is no problem and its smooth to drive.

Dave