Raylon

Hey guys, just purchased an MHZ Shockwave-M. The boat has Speedmaster hardware, Castle Barracuda 80, and a Feigao 540 10XL motor. I was told the boat has run with two 3s Lipo's in series before, but I am not sure if I believe this. The manual for the Barracuda only recommends up to a 4s battery, so I am thinking a 6s would surely damage it. It only has a voltage cutoff up to 4s also. Or I may be completely missing something here also.

I ordered two 3s 4900mAh 25C packs from HobbyKing. I plan on running using just once of the 3s batteries, and seeing how the run time is, speed, temps, etc. If the boat is way out of balance or run times are short, I plan on trying parallel connection, but I am thinking that the boat may start to get weighed down with those two big batteries in it.

So, any thoughts? Also, anyone else own one of these boats? I really haven't seen much about them at all. Will get some pictures up Thursday.

EDIT: Video of boat running!

http://www.youtube.com/watch?v=rRl_Z5Z4j3k

ROMA-F1

hi mai name roma-f1 ... WELCOME rcuniverse......

westbeach

Raylon,

You need to run your batteries in Parallel, not series. Series would yield disaster as you would double your voltage from 11.1V to 22.2V however if you ran parallel, your voltage stays the same at 11.1V but your capacity, MAH would double resulting in longer run times. What props do you have currently with your setup? This is an important factor as the amp draw from running too big a prop would cause the motor to overheat and sending your esc in smoke.

Raylon

That is what I had figured. Do you have a picture of batteries in series? I would like to see how it is wired before I start soldering things. Right now, I have no props except for the one on the boat, which I don't know what it is. I have the prop that is stock on the Thundercat31, and an Octura M445. I'm guessing the 445 would be too large, but not sure about the stock one, it is quite a bit smaller.

SV27dayton

Parallel simply means that you tie the two positives together and route them to the red wire on the ESC and likewise with the negative to blue. If in series you'd tie one positive the the negative of the other and connect the remaining two to the ESC properly. If still confused some of the nimh web sites have some good diagrams.

Raylon

Okay, obvious Mono noobie here. The rudder is offset to the right quite a bit. Two trim tabs, and only one turn fin on left side. Ran it for first time today and if I attempt to turn right, it almost wants to flip over it leans so much. If I turn left though, it looks beautiful. Normal? Also, almost 40 minutes on one 4900mAh battery.

Raylon

Hopefully someone can answer questions above. Had the boat out again today. Was able to take some pictures. Got some temperature readings. After a 15 minute run the motor was at 90, battery at 80, and ESC at 145. What would be causing ESC to be so high? It has water cooling, and it gets hit with the water first, before the motor. I got those readings from two capacitors I beleive they were on the outside of the ESC, not the shrinkwrapped ESC itself.

maverick pro

hey ryan...take a look at the speed control programing. remember i ran it on nimhi so everything is set to max with no lipo voltage cutoff. try that and see what happens.

mike

Raylon

Yea I totally reprogrammed the ESC as soon as I got it. I even have the settings on Low Power/Max Battery Life.

maverick pro

thats weard...it never ran that hot here and the water is hot 81-85

...mike

maverick pro

hey ryan...ran my skater today. motor temp was 405 lol. esc was very hot to. did you ever get it figured out?

mike

westbeach

Raylon,

Please post a pic of your transom, this can give us a better idea of whats causing issues.

Raylon

Here is the best I have at the moment. If it's not good enough, I can go take a better one.

westbeach

Raylon,

The stinger looks real long ,must just be the angle you took the pic. Where does the leading edge of the rudder sit in comparison to the prop. It looks like the rudder standoff/bracket is a little short to me? But hard to say due to the angle of the pic. Have you checked your servo throws? Make sure they are the same travel for left and right. Where is the CG of this hull? Where is your battery positioned? Maybe take a side view of the transom of the boat, so I can see where the rudder sits in comparison to your stinger. And also a shot from above of your layout. Motor/esc/batt etc....

Raylon

Yep, servo throws are the same. I believe it turns funny just because I am only used to a cat and the offset rudder. I ran the boat again and it ran pretty well. Here are some more pictures.

westbeach

Raylon,

You're using the wrong hardware on this little boat. Your rudder should not be that far off to the side. It's almost acting like a turn fin/rudder. You need to get a strut with a built in rudder. MAke sure your left turn fin is 90 degrees to the vee of the hull. Every thing else looks good. Just your rudder and stinger. Too big IMO for a hull that is only 5" wide. I see that MHZ sells a strut/rudder part number 1083 specifically for this hulls. The only option without having to replace the stinger and strut is to get a rudder with the attaching bracket on the right hand side instead of left hand side as it sits currently. This will improve the handling but the rudder needs to sit close to the stinger as possible.

Raylon

I see 1083 is a preorder item. I bought this boat used, from a person who bought it from a guy who sounds like he knew what he was doing when he built the boat. This boat is definietly built as a high speed setup. It controls very well at high seeds. I bought this boat on a budget, and there is a 0% chance that the hardware will be changing. I appreciate the help though.

Anybody have any idea why the ESC is hot? I read on another thread that if you don't run at full power the ESC has to 'eat' the extra energy and gets hot. I was only running at about half throttle on my runs. Is this a plausible explanation?

westbeach

Raylon,

You could get away with only changing the rudder bracket. By means of making your own, remembering to keep the rudder as close to the stinger as possible, without hitting the prop!! I doubt that person knew what he was doing, because the hardware is all wrong for this size of boat. It may run real well in the straights but what's the point unless you're racing SAW's and trying to set a speed record.

As far as your ESC running hot, half throttle will cause the heat to build up. You need to run WOT. Unless you run a brushed setup. Good luck with the boat!

maverick pro

hey guys just a thought but will a trim tab with the same style turn fin on the right side help this at all. or is the rudder still to long? the boat did do the same when i hade it but i think maybe less because i used neavy cells. but if you lean it over fare in the right turn it would blow the back out.

...mike

Cornelp

Definitely a new bracket. The rudder needs to be closer to the prop and a bit further back, aligned with it. I had a setup like this and it did turn funny... If you setup the strut correctly, you can also lose the trimtabs and do a turnfin on the right side only. That is if you only take right turns...
Below are examples of simple home made hardware that works 100%....

westbeach

Trim tabs are a hit and a miss. Best to try it with and without. I don't run trim tabs on my DF Storm mono whereas a lot of guys do! Turn fins do help stabilize the boat, specially at high speed turns. But proper setup is crucial on how the boat runs and handles. The biggest problem here is the rudder bracket being too short in relation to the prop and the position of the bracket too far right. Signing off!

Raylon

Hey guys, just got donerunning the Shockwave. Was running in quite windy conditions, and it toughed it out quite well. Not a mostly full throttle run at all, but I'll call it a mostly 3/4 throttle run. Got the boat out of the water, and took temps. Battery was about 125, motor 115, ESC 175. Ok here is my question. What part of the ESC should I be measuring the temp? The part I measure are the two capacitors that extrude from the shrink wrap. If I measure just the shrink wrap right in the middle of the ESC, the temps are around 125.

Also, I have a carbon prop, a bronze prop the same size as carbon, and then a smaller bronze. I normally run the carbon, which came with the prop, but what kind of affects could I see by using the other two props? Would the temp on the ESC go down by switching to the smaller prop? Video coming up soon of todays run.

Here is video:

http://www.youtube.com/watch?v=rRl_Z5Z4j3k

maverick pro

hey ryan...i like the video. it looks faster than when i had it.

mike

Raylon

Time to resurrect a super old thread! I just got a chance to run the boat after a long winter, finally hit the 60 degree mark here in Missouri today, so I had to take the boat out. Was finally able to run WOT at my lake. Usually way too windy. Boat is pretty bouncy at high speeds, even with the heavy Lipo and a eTrex inside it. Speeds topped out at 39.8 before the GPS crapped out. It's so old that if it experiences a hard knock, it turns off. I am assuming that it got knocked off in one of the barrel rolls that occured. Video of the wreck here:

http://www.youtube.com/watch?v=LjcMecWb-nI

You can also check out another one of the boat. I submarined it pretty good. Make sure you change it to 720p! My roommate did a pretty good job with the camerawork.

BACKEMF

Flip the rudder mount upside down and the prop will be closer and it will handle much better.

You need to round to top of the mount off so it still has kick up function. You also need to drill out the small hole for the larger bolt if that is speed master rudder.

Simple fix, should take less than 1/2 hour or so...

A 10 xl is 1200KV and runs Very nicely on 6S 1P but you will need allot smaller prop. This will reduce torque roll and further help stability.

Get a better esc, the Barracuda is old, the caps are soon too pop and messy smelly.

Turnigy light blue marine esc, $60, your laughing.

I cannot see where you say what is prop diameter???

For 6S/1P 1200KV xl can, try 37mm prop, 215prather, 40mm carbon. Watch temps and bring extra Gitch with you.


Actually its about 1400 kv, but still that is fine, just try 37mm first please, very fast setup, but fun!