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pavmentsurfer
04-03-2012, 05:19 PM
Finally got a chance to run my boat today. I used a couple 5400mah 2S SPC hard case lipos (50C) and at first the boat wanted to drive straight under water. I raised the strut to about 2mm above the sponsons when the boat was flat on a table and I raised the turn fin all the way up. I have done nothing else.

I like the boat. It goes good. Handles the chop exactly how I had hoped it would. But I want to know if it should be lifting its nose more than it is now.

After a 5 minute run the motor and ESC were cool to the touch. Water is COLD right now so thats helping but I've got a 42X55 Grim prop on its way. Maybe that will give me a bit more speed? I think the electronics can take it.

What do you think based on this video? Is the setup right? If not, what should I look at adjusting next?


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

pavmentsurfer
04-07-2012, 12:56 PM
Man, not alot of action in here is there? I installed my grim 42X55 prop which gained me more speed but didnt lift the nose any more so i tried a different setup the other day and met with marginal success. I lowered the strut so its flush with the bottom of the sponsons and perfectly level... this actually helped bring the nose of the boat up. But it still rides really wet compared to the other videos im seeing.

Anyone have any suggestions for how I can get the nose up. I may try raising the strut 1/8 just to see what happens. My batteries are already as far back as they can go... it must be a strut angle thing. I feel like I want to "trim" it up as I would in a full size boat. As in, adjust the strut angle so the rear of the strut is higher than the front. But I cant seem to accomplish this due to the brass tube being so tight to the strut. Anyway, any advice would be great.

pavmentsurfer
04-07-2012, 08:08 PM
So I tried dropping the strut another 1/16 or so and ran the boat again today. Made a huge difference. After about 50 feet on a straight away at WOT it would start to lift its nose and run just on the rear of the sponsons. Noticeably faster also. Lake was nearly glass and everything was perfect until a rogue gust of wind sent the boat for 2 completely flips in the air leaving it upside down. Luckily we have an old paddle boat on shore and I was able to rescue it.

Overall... best day of running yet. Im wondering if maybe I should try dropping the strut another 1/16. Ill probably try that tomorrow. Im getting about 7-8 minute runs out of my 5400mah 2S 50C hard case packs until they hit my LVA level of 3.6vpc. I have it purposely set higher than I normally would to protect the packs as these are also my main packs for running all my trucks and cars. I use the LVA because the LVC built into the Aquacraft ESC is only set at 3VPC or 6 volts per pack... which is just way too low IMO.

I have a Turnigy 120amp Marine ESC on its way which has an adjustable LVC. Once I get that installed I won't need to run the LVA anymore. Which will be nice.

ksaucerman
04-07-2012, 11:18 PM
You can also put a little positive in the strut and move the batteries back a little. Usually the bottom of the strut is even with the back of the sponsons.

pavmentsurfer
04-10-2012, 11:46 PM
Positive being the nose of the strut is higher than the rear? That was what I was thinking, I called it "trim" because thats what we call it on our full size boats.

I dropped the strut another 1/16 and it made an ever bigger difference the other day. Still not totally happy with how far out of the water the boat is getting. It also appears to run more wet on one side that the other. I wonder if thats maybe due to the rudder being on one side. Still, faster and riding farther out of the water than ever so I'm going to keep fiddling with it.

Im also going to scuff the bottom of the boat as I've heard suggested before. Seems like it can't hurt. Im sure its not going to make a huge difference but it'll give me something to do while i wait for the weather to improve.

ksaucerman
04-10-2012, 11:58 PM
Yes positive is trimmed up. It is probably neutral now meaning it is level. A little positive will make a big difference just like it does on your full size boat when you trim up for speed.

siberianhusky
04-11-2012, 06:37 AM
Where is the cg set? I've never had to run any angle in the strut of mine at all.
My strut bottom is 1/16" above the sponson bottoms, and dead level.
This boat is fairly sensitive about the CG. Doesn't take much of a change to really effect the running attitude.
Get the CG right for starters then work on strut adjustment.
Depending on the water conditions mine varies between 28 and 30%.
An m445 is a good prop on this boat but it about the max size for it, temps will be about as high as I feel comfortable with.

pavmentsurfer
04-12-2012, 11:50 AM
Siberianhusky, your sig makes me laugh every time I read it.

I don't know where my CG is at... but the packs are as far back as they can go. I can't imagine moving them forward could help with what I need... ill see how the CG is set when I get a chance.

Here are a few pics of my boat stand. I know most of you have boat stands like this but I've never build one before. $20 and about 30 minutes and its done. I have velcro straps on it so when I transport the boat its held down to the stand...

http://i844.photobucket.com/albums/ab7/pavmentsurfer/Boats/DSC02355.jpg
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Boats/DSC02354.jpg
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Boats/DSC02353.jpg

siberianhusky
04-13-2012, 06:34 AM
http://www.youtube.com/watch?v=l4-PEVVs2Ug&list=UUfd0fnVWaTbIdv54Nqco-IA&index=6&feature=plcp

mine running in rough weather, some wind and waves that day. It even flies and lands nice off the waves.
It all goes hand in hand, you have to get the cg right for any of the other changes to work right. I do know I've never had the batteries in mine all the way back, I couldn't make a half lap that way without it blowing over backwards.
Was turning a smaller prop that day, because of the wind and waves I slowed the boat down a bit so I could get some good runs.
It's better to prop down and still run the esc wide open, less heat buildup than running part throttle.

pavmentsurfer
04-14-2012, 11:17 PM
So is that a stock motor and ESC cause that is WAY faster than mine. Im only running 2X 2S 5400mah hard case packs. They aren't very heavy... which is why they are all the way back. But I'm so confused as to why it seems to easy for everyone else to get the nose WAY up and mine just won't.

I have even noticed one SIDE of the boat runs more wet than the other. When the boat is crossing left in front of me (so that would be the drivers left side of the boat) the sponson runs nearly half in the water. When the boat is traveling right (drivers right side of the boat) the sponson is almost fully out of the water. Im not a boat guy, I know RC trucks. This is confusing to me. But I'm determined to sort it out, hopefully with your help... hehe.

siberianhusky
04-15-2012, 04:22 AM
Probably prop torque, yep thats all stock, either 2 2s 5300 mah gens ace or 2 2s 5000mah enerland batteries.
One thing that helps is keeping notes on your changes, makes it much easier to see what a change actually did. Also only make one change at a time, first off would be setting the cg @ 30%, keep the strut level and play with the height. Mine is usually just above the sponson bottom.
The only real change to mine is a drop in SV27 rudder with a water pickup, it mounts right up to the MC bracket, same size and shape.
I tried a 2030kv UL-1 motor and went back to the 1800kv, seems to run better with a bigger prop @ lower rpm.
Raising the strut will bring the nose up, lowering will drop the nose, think of it pivoting around the cg. Prop higher will let the stern settle and raise the bow.

D for Dummy
04-15-2012, 07:24 PM
Your boat is running good.

I have two Aquacraft Motley Crew Catamarans. GrimRacer 42x55 prop seems to be the best. I'm running two GrimRacer 2s 5000mAh 40c Li-Po, very happy with these over other non-name brand batteries.

My strut is about 4mm below the sponsons while flat with prop and water pick-up hannging off the edge of the table. Seems the best location. I move the batteries forward or back based on water conditions.

I have about 5 videos here: http://www.youtube.com/user/dfordummy

I spoke with GrimRacer yesterday at the Toledo show. He said that is one of the most optimum setups. He said the only thing different that his setup is that he is running a single 4s 500mAh 40c on the right side.

pavmentsurfer
04-15-2012, 07:51 PM
siberian, thats exactly what I expected from raising and lowering the strut. But I found the opposite at first. I think it was because I ended TOO high on the strut and the prop was caveatting and therefore loosing the lift I needed to get the nose up. So I lowered it to level with the sponson and the nose came up... then I dropped it 1/8 more and the nose went up again. I then attempted to raise the rear of the strut a tiny bit and I got a tiny improvement with that again. I was moving my packs back at the same time until they were as far back as they can go.

Im going to attempt raising the strut back to level again... now that I've ended with my packs all the way back, maybe raising the strut will have a better effect.

Hmmm... D for Dummy, you videos just made me think I need to do more work. Your boat really looks like it gets out of the water. Im going to do more fiddling.

I also just picked up a deal on a couple EZrun 4065 4 pole motors. They are 2700kv and I realize thats really high. But these are 40mm's and 65mm long. I bought a 40mm leopard water jacket from e-bay and I'm going to try this setup just for fun with my Turnigy 120amp ESC. Ill post a video when I get it all tested. Im not saying ill run this setup full time. I just got such a great deal on the 2 motors and I can always use them in one of my trucks... but I figured id see how they ran in the boat first.

Thanks for all the advice guys. Im going to see about testing my COG with the packs in and re-setting the strut again. Im also going to look into the SV27 turn fin with the built in water pickup. Thats a cool idea.

D for Dummy
04-26-2012, 03:08 PM
I find my Motley Crew has slight porpoising when at full speed in a slight chop (wind ripples in the open bay as seen in the videos on my profile page). This is with the batteries all the way back, running into the wind brings the risk of blowing over. But the boat really runs great!
However, in a glass calm pond the boat runs very flat, but fast, almost too flat. In fact, it sounds like it is a few less RPM than in the chop, naturally. It might run a little better in a glass calm pond with the prop de-tongued and or cupped. I'm not a fan of running in glass calm water (unless running my Stiletto 29 Proboat). I'm choosing not to dial in my Motley Crew for those conditions, after all it is an offshore style boat and performs amazingly well in the chop, small waves and varible water conditions. Did I mention yet that I now have a second Motley Crew? (Great boat!)

G-UNIT
04-26-2012, 04:59 PM
Positive strut angle would be that thr prop would be pointing to the surface, which pushes the aft down and the nose up, this is if you want to run alittle dryer,
prop pointing downward would cause the the aft to be pushed up and the nose down to run wetter.

dana
04-26-2012, 05:33 PM
heres a video of some of my friend an i running our boats. there is a motley crue in here running 3 different prop and cell counts. pay attention to catch them. he has his strut set all the way up, but i suppose all boats are not the same. this is what worked for him. he is running stock motor and t180, although a 120 would be fine. anyways here ya go you have to watch the whole 5 minutes because the motley appears in the middle and at the end ch33rs! http://www.youtube.com/watch?v=0F7t1NIXm0o

pavmentsurfer
05-03-2012, 10:18 AM
Well, I'm in myrtle beach right now on holidays and the MC came with me. Theres a small pond in the centre of the park where were staying and I've been running the boat every day at least twice. Its amazing the difference calm VS mild chop makes in how this boat runs. I ran it on glass and it ran nearly flat in the water. The sponsors were wet all the way down. Nothing I did could bring the nose up. Ive mostly run it in mild chop (wind ripples to a max of 2 inch small waves) and it just floats on top of the water with only about 1 inch of the sponsons wet. Its amazing. Its SO much faster this way and I'm not changing a thing. Packs are in exactly the same location, I havent touched the strut. I found the boat goes faster into the wind but, of course, the risk of blow over is greater (did a great double gainer this morning... landed on its hull and kept going). Overall this boat is attracting ALOT of attention here at the park. I probably had 15 people out watching me this morning, asking questions. Just gotta watch for fishing lines. I snagged one at the end of my run. Luckily it just caught the rudder and not the prop but apparently people leave them out in the pond even while they aren't fishing.

Anyway, I'm going to try and get my wife to take a quick video later on today when the babies sleeping.

D for Dummy
05-04-2012, 12:08 AM
I agree, I love running in 1-2in chop. Today we ran in 6in+ waves, lots of subs, lots of blowovers.

More videos on my YouTube:
http://www.youtube.com/user/dfordummy/videos

Old Sloppy
05-04-2012, 12:46 AM
where in Myrtle Beach is that pond?
I will be there soon and wonder if the pond is suitable for larger/faster hulls?
I have a 18" mono or a 60" Cat, I guess the Cat would be too much.....

Harry
from Atlanta

pavmentsurfer
05-09-2012, 11:13 PM
Its at a trailer park on the beach called Pirateland. The people there seem to LOVE electric boats but anything with a gas motor would be too much for them. Im uploading a video to youtube right now and will post here once its done. You can get a feel for the size of the pond. Perfect for a 30 inch cat for sure. Id have 10-15 people "spectating" every run. I ran twice a day minimum, most days I got through 4 sets of packs. Only one flip that ended with the boat upside down. Sat on the shore for about 10 minutes while the boat floated to me, flipped it back over and kept going. This boat is sweet.

heres some pics. They are screen caps from the video I'm uploading so the quality is pretty bad. But they have a nice action feel to them. As you can see, the boat is running VERY dry now. I have an SV27 rudder to go on so I can run both water pickups. I also have the Turnigy 120amp ESC to go in it. Unfortunately, the boat had to stay in myrtle beach at my parents trailer till they bring it home in about 3 weeks. So, till then, ill just be remembering the good times.
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/IMG_0496.png
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/IMG_0498.png
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/IMG_0495.png
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/IMG_0499.png

pavmentsurfer
05-10-2012, 09:04 AM
Heres the video I took on holidays.


http://www.youtube.com/watch?v=IflFo-zYz10&list=UUY2QkNwEn9ox9k4C7bf-dwg&index=1&feature=plcp

bdp1174
05-10-2012, 04:00 PM
Looks like it's running pretty good I am tring to get my MC dialed and and wonder if you can help me.I put my boat on a table after raising the pickup and put the strut flat and level touching the table like grim suggested(had to bend the stuffing tube slightly to try and get the srut level, had about 1-2 degree angle down out of box) and running 2 2s lipos centered on the velcro.It seems like it is running a little faster but the nose is not coming up very much and takes a little longer to get on plane than the stock strut level out of box.Sometimes it seems it want to push the nose down towards the water on inital throttle then it gets on plane and runs ok but I am not sure what else to try.

How is your strut adjusted? Also where are you running your lipos in the boat?

Thanks,
Brandon

pavmentsurfer
05-10-2012, 05:28 PM
I have my strut about 1/8 LOWER than the bottom of the sponsons. I could probably try and go up a bit. But I found when I went further up it stopped lifting the nose. I also have it angled UP just a bit (so the nose of the strut is higher than the tail). This worked for me but the biggest thing I changed that helped from my initial setup was moving the batteries all the way back. This is going to be determined by what size and weight batteries you have, mine are relatively light 2S hard case packs and I have them all the way back. This made a HUGE difference for me. I was having the same problem you were with the nose "sticking" to the water... I couldn't get it to lift and "fly" the way I wanted to. Now, as you can see, it flys great. My next adjustment will be to level the strut again the way Grim suggested and try that with my packs all the way back. Not sure what effect that will have but its worth a try.

bdp1174
05-10-2012, 05:44 PM
Did you run into any issue with the boat getting on plane at all like I am having?
Btw I am also using a grim 42x55 prop.
When u say all the way back is that with the front of the batteries barely on the velcro?

pavmentsurfer
05-10-2012, 06:05 PM
All the way back means the packs are touching the raised area for the servo and ESC... pushing them as far as they will go to the rear of the boat. Mine still has quite a bit of velcro overlapping but its the back of the packs are not on the velcro. Id get a pic if the boat wasn't still on holidays with my parents.

When I was first trying to get the boat to lift its nose I was raising the strut by 1/16 increments and eventually I got to a point where the boat would barely take off. Now, when you first hit the throttle it cavitates a bit (spins but doesnt go very fast) then once the boat starts moving it just jumps and takes off. This is normal as I understand it.

bdp1174
05-10-2012, 07:13 PM
Ok that is what mine is doing.I just got in 2 new gens ace 5300 2s 30c lupos today and will be trying these out as soon as I solder on some ec5s to them.
I will post my results and try to get a video of how it runs so you can see it and let me know if it looks like its running good or not.
Thanks again for your help.

Brandon

Brushless55
05-11-2012, 05:32 PM
Ok that is what mine is doing.I just got in 2 new gens ace 5300 2s 30c lupos today and will be trying these out as soon as I solder on some ec5s to them.
I will post my results and try to get a video of how it runs so you can see it and let me know if it looks like its running good or not.
Thanks again for your help.

Brandon

I have those same packs, lets me know how you like them..

Old Sloppy
05-12-2012, 04:29 PM
Are 5300 Lipo's a little large/heavy for that size hull?

I understand the need for lots of run time and I understand the larger cells have a higher amp capibility.

Just seems a 3700 lipo would jump on plane faster due to less weight.

Harry

xlandguy
05-13-2012, 02:31 AM
Wow, I was just looking at batteries and weights online and wondering how much a few ounces can affect these boats. Quite a bit I imagine. So getting some 8,200mah batteries that weigh .9 lbs would be a foolish thing for me then. I own an AC Motley Crew. I run SPC 5,000's and Sky Lipo 4,400. THese are hardcase but from now on I do believe I will buy nothing but NON hardcase batteries. I like the idea of being able to interchange batteries between my boat and my Traxxas Summit, also a 4s machine. The SPC batts I have are only 25c but very good quality I believe, the Sky's are 40c. I got my SPC's soaking wet due to my hatch compartment filling with water. But after opening the case and drying them there seems to be no affect.

pavmentsurfer
05-14-2012, 03:43 PM
Im not sure the extra weight of a hard case VS soft case will make that much of a difference. Not as much as say, buying a 50C SPC VS the 25C SPC pack will. My packs get HOT in this boat and I can only imagine how hot the 25C packs would get. It was recommended to me not to run anything less than true 40C packs... which is why I sold all my old packs (I had a few of the 5000 25C packs as a few 6000 30C packs) and bought new 50C packs... and they still get hot. I run them in my EREB, Summit and the MC. I have 8200's but only run them in my summit as they are only 30C.

xlandguy
05-14-2012, 04:22 PM
Well I don't get how the ESC is 60 amp but the boat seems to pull more than that? And a 6,000mah 30c can do 180 amp continuous, way more than the ESC is rated for??? I would think those batts are plenty for this boat.

Old Sloppy
05-14-2012, 07:10 PM
[QUOTE=pavmentsurfer;416953I have 8200's but only run them in my summit as they are only 30C.[/QUOTE]

a) 8200 30c = 246 amps rating

b) 5000 50c = 250 amps rating

c) 15000 40c /2 = 300 amps rating

this is what I run in my Cat, I have 2 motors so the 300 amps rating ( actual 15000 40c = 600 amps, but it is devided by 2 motors)

My batteries do not get hot. I estimate 125.3 amps (per motor).

Harry

Brushless55
05-14-2012, 08:08 PM
Well I don't get how the ESC is 60 amp but the boat seems to pull more than that? And a 6,000mah 30c can do 180 amp continuous, way more than the ESC is rated for??? I would think those batts are plenty for this boat.

Higher amps maintains Voltage, more Watts, more RPMs = higher speeds

DjFlipNautikz
05-16-2012, 01:06 PM
i run two 5000mah Turnigy 4s batteries in parallel. i actually have never tried 2s batteries because 3s and 4s is all i have. here is a video of her running.


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

xlandguy
05-16-2012, 03:01 PM
So you get what, 10 mins runtime with the two 4s in parallel? Motor must get kind of hot running that long? And it looks like its going pretty good even with the added weight of all that battery!

Brushless55
05-16-2012, 03:24 PM
So you get what, 10 mins runtime with the two 4s in parallel? Motor must get kind of hot running that long? And it looks like its going pretty good even with the added weight of all that battery!

If your cooling is setup proper, you wont have heat issues not matter how long you run
and on the flip side, a cooling system setup wrong wont last 1min :tiphat:

pavmentsurfer
05-17-2012, 12:34 AM
Im not sure that 60 amp ESC rating is entirely correct. If I'm getting 2 50C batteries really warm after a run its obviously pulling a heck of alot more than 60 amps. Ive got a Turnigy 120amp ESC to go into this boat. I bought it mostly for the adjustable LVC... but I was thinking maybe it would also be more robust.

I got my battery information from the guy who actually sells the SPC packs that I run. Tom from SPC. His answer was that when the 8200mah pack is full then yes, your amp ratings are correct. However, when the battery is being drained and there is less MAH in the pack, your amp ratings drop as well. At the end of a run you may be pushing that pack too hard. Whereas a 50C rated pack can still deliver the amps when its empty because it is a true 50C... it sounded like good logic and Tom has never steered me wrong. He has an SV27 and runs it pretty hard. He also has thousands of dollars in data logging equipment and battery testing equipment. So, I trust that he knows his stuff.

Brushless55
05-17-2012, 12:50 AM
Im not sure that 60 amp ESC rating is entirely correct. If I'm getting 2 50C batteries really warm after a run its obviously pulling a heck of alot more than 60 amps. Ive got a Turnigy 120amp ESC to go into this boat. I bought it mostly for the adjustable LVC... but I was thinking maybe it would also be more robust.

I got my battery information from the guy who actually sells the SPC packs that I run. Tom from SPC. His answer was that when the 8200mah pack is full then yes, your amp ratings are correct. However, when the battery is being drained and there is less MAH in the pack, your amp ratings drop as well. At the end of a run you may be pushing that pack too hard. Whereas a 50C rated pack can still deliver the amps when its empty because it is a true 50C... it sounded like good logic and Tom has never steered me wrong. He has an SV27 and runs it pretty hard. He also has thousands of dollars in data logging equipment and battery testing equipment. So, I trust that he knows his stuff.

UHHHH???
so he Tom says that the 50c he sells can deliver what he says the packs can and others don't?
so he is saying that the 8200mah 30c (240A)pack when they are down to 1500mah only deliver 60amps but his 50c remain the same
not good logic at all, actually bull :censored: really...

and what temp is warm with your packs?
90*F
100*F
???*F
packs can get to about 140*F without harm
most packs heat up good when they go beyond 80% use
if you have 20% and greater left in the packs after a run and they are hot, then they are not true 50c to begin with..

pavmentsurfer
05-17-2012, 01:02 AM
Tom says the packs he sells have been tested and proven to deliver a minimum of 50C... whereas MANY other companies packs DONT deliver their actual C rating. Im AM saying that yes.

However, what I'm NOT saying is what you wrote about the 8200's. Keep in mind, those packs are SPC's as well. What he said is that a 30c pack that is down to 1600mah is not putting out as many amps as a 50C pack that is down to 1000mah. I don't run my packs below 3.6vpc just to be safe but the logic says a pack with a higher C rating will be delivering more amps when it gets low than a pack with a lower C rating. it makes sense.

If you do the math, An 8200mah 30C pack that has been run down to %20 capacity now has 1600 (approx) mah remaining. 1.6X 30 = 48amps... thats what the math says.
A 5000mah 50C pack that has been run down to %20 has 1000mah remaining. 1 X 50 = 50. So yes, the 50c pack at %20 remaining is capable of delivering more amps.

What would be ideal would be an 8200mah 50C pack. Then, IT would be putting out more amps than the 5000mah 50C pack at %20 capacity.

When i bought my boat i asked tom what packs would be better to run. my 5000mah 50C's or my 8200mah 30C's. He said the 5000mah packs would be better as they would be capable of putting out more amps as the pack drained. I didnt question him, I just did it.

My packs currently temp at around 120 degrees at the end of a full, non stop run. Thats the outer plastic of the hard case so I'm sure the cells inside are a bit warmer.

Brushless55
05-17-2012, 01:26 AM
Tom says the packs he sells have been tested and proven to deliver a minimum of 50C... whereas MANY other companies packs DONT deliver their actual C rating. Im AM saying that yes.

However, what I'm NOT saying is what you wrote about the 8200's. Keep in mind, those packs are SPC's as well. What he said is that a 30c pack that is down to 1600mah is not putting out as many amps as a 50C pack that is down to 1000mah. I don't run my packs below 3.6vpc just to be safe but the logic says a pack with a higher C rating will be delivering more amps when it gets low than a pack with a lower C rating. it makes sense.
If you do the math, An 8200mah 30C pack that has been run down to %20 capacity now has 1600 (approx) mah remaining. 1.6X 30 = 48amps... thats what the math says.
A 5000mah 50C pack that has been run down to %20 has 1000mah remaining. 1 X 50 = 50. So yes, the 50c pack at %20 remaining is capable of delivering more amps. What would be ideal would be an 8200mah 50C pack. Then, IT would be putting out more amps than the 5000mah 50C pack at %20 capacity.

When i bought my boat i asked tom what packs would be better to run. my 5000mah 50C's or my 8200mah 30C's. He said the 5000mah packs would be better as they would be capable of putting out more amps as the pack drained. I didnt question him, I just did it.

My packs currently temp at around 120 degrees at the end of a full, non stop run. Thats the outer plastic of the hard case so I'm sure the cells inside are a bit warmer.

first off, I quoted what you said about what that moron said
his logic that he has you believing is 100% WRONG! :blink:
his math is dead wrong..
if you run a lipo that can only put out 50a, you will jack them up!! :scared:
and IMO the 8200's would be the better pack as you will have about 50% more runtime :tiphat:

and again, most packs will heat up if ran beyond there 80% capacity
if your not doing this and they are getting hot, then that tells me they are not true 50c packs :cool2:
I have 40c Turnigy packs in my P-Spec that the motor pulls 80a cont and they only get about 105* after a race.. so what does that tell you? :sneaky2:

and by the way, 3.6v per cell is not a safe range, that's about 100% empty...

pavmentsurfer
05-17-2012, 09:24 AM
Well, this thread jumped into territory I'm not comfortable with pretty fast. The math I'm using to determine how many amps the pack is putting out is not MINE or TOMS... its the math everyone uses to calculate amps. So I can't really see how that can be WRONG. MAH/1000 X C = amps. Its the math that everyone uses. But no big deal.

I don't appreciate you suggesting a person I know and trust is a "moron". There is NO need for name calling or insults here. Maybe its acceptable on this forum. Its not what I'm used to and Id prefer it be kept out of this thread.

Finally, you can say what you want about the packs I'm running. They are tested and proven to be 50C, if not higher. Im very happy with them. From my understanding of how amps and lipos work, it makes sense to me and ill be sticking with the logic. Run times aren't the most important factor to me. But I'm new to boats. So clearly I don't know anything about RC electronics right.

For the record, 3.4 volts per cell is empty. at 3.6 volts per cell I'm putting about 4000mah back into my 5000mah packs when I charge. By my calculations, thats %20 remaining.

Brushless55
05-17-2012, 10:13 AM
......

Brushless55
05-17-2012, 10:26 AM
Im not sure that 60 amp ESC rating is entirely correct. If I'm getting 2 50C batteries really warm after a run its obviously pulling a heck of alot more than 60 amps. Ive got a Turnigy 120amp ESC to go into this boat. I bought it mostly for the adjustable LVC... but I was thinking maybe it would also be more robust.

I got my battery information from the guy who actually sells the SPC packs that I run. Tom from SPC. His answer was that when the 8200mah pack is full then yes, your amp ratings are correct. However, when the battery is being drained and there is less MAH in the pack, your amp ratings drop as well :doh: .

At the end of a run you may be pushing that pack too hard. Whereas a 50C rated pack can still deliver the amps when its empty because it is a true 50C... it sounded like good logic
and Tom has never steered me wrong. He has an SV27 and runs it pretty hard. He also has thousands of dollars in data logging equipment and battery testing equipment. So, I trust that he knows his stuff.


UHHHH???
so he Tom says that the 50c he sells can deliver what he says the packs can and others don't?
so he is saying that the 8200mah 30c (240A)pack when they are down to 1500mah only deliver 60amps but his 50c remain the same
not good logic at all, actually bull :censored: really...

and what temp is warm with your packs?
90*F
100*F
???*F
packs can get to about 140*F without harm
most packs heat up good when they go beyond 80% use
if you have 20% and greater left in the packs after a run and they are hot, then they are not true 50c to begin with..


Tom says the packs he sells have been tested and proven to deliver a minimum of 50C... whereas MANY other companies packs DONT deliver their actual C rating. Im AM saying that yes.

However, what I'm NOT saying is what you wrote about the 8200's. Keep in mind, those packs are SPC's as well. What he said is that a 30c pack that is down to 1600mah is not putting out as many amps as a 50C pack that is down to 1000mah. I don't run my packs below 3.6vpc just to be safe but the logic says a pack with a higher C rating will be delivering more amps when it gets low than a pack with a lower C rating. it makes sense.

If you do the math, An 8200mah 30C pack that has been run down to %20 capacity now has 1600 (approx) mah remaining. 1.6X 30 = 48amps... thats what the math says.
A 5000mah 50C pack that has been run down to %20 has 1000mah remaining. 1 X 50 = 50. So yes, the 50c pack at %20 remaining is capable of delivering more amps.
100% WRONG!

What would be ideal would be an 8200mah 50C pack. Then, IT would be putting out more amps than the 5000mah 50C pack at %20 capacity.

When i bought my boat i asked tom what packs would be better to run. my 5000mah 50C's or my 8200mah 30C's. He said the 5000mah packs would be better as they would be capable of putting out more amps as the pack drained. I didnt question him, I just did it.

My packs currently temp at around 120 degrees at the end of a full, non stop run. Thats the outer plastic of the hard case so I'm sure the cells inside are a bit warmer.


first off, I quoted what you said about what that moron said
his logic that he has you believing is 100% WRONG! :blink:
his math is dead wrong..
if you run a lipo that can only put out 50a, you will jack them up!! stupid logic for sure..
and IMO the 8200's would be the better pack as you will have about 50% more runtime :tiphat:

and again, most packs will heat up if ran beyond there 80% capacity
if your not doing this and they are getting hot, then that tells me they are not true 50c packs :cool2:
I have 40c Turnigy packs in my P-Spec that the motor pulls 80a cont and they only get about 105* after a race.. so what does that tell you? :sneaky2:

and by the way, 3.6v per cell is not a safe range, that's about 100% empty...


Well, this thread jumped into territory I'm not comfortable with pretty fast. The math I'm using to determine how many amps the pack is putting out is not MINE or TOMS... its the math everyone uses to calculate amps.
No one on these forums uses this bogus logic when the pack is being used up!
So I can't really see how that can be WRONG. MAH/1000 X C = amps. Its the math that everyone uses. But no big deal.

I don't appreciate you suggesting a person I know and trust is a "moron". There is NO need for name calling or insults here. Maybe its acceptable on this forum. Its not what I'm used to and Id prefer it be kept out of this thread.
Ok so the guy is a used car sales man or something?? using bogus logic to sell you his packs and to over look some other packs that could be a better choice..

Finally, you can say what you want about the packs I'm running. They are tested and proven to be 50C, if not higher. Im very happy with them. From my understanding of how amps and lipos work, it makes sense to me and ill be sticking with the logic. Run times aren't the most important factor to me. But I'm new to boats. So clearly I don't know anything about RC electronics right.
LOL

For the record, 3.4 volts per cell is empty. at 3.6 volts per cell I'm putting about 4000mah back into my 5000mah packs when I charge. By my calculations, thats %20 remaining.

most pack are about done at 3.6v per cell.. you might have about 10% left in the packs
all my packs when they are at about 3.7v per cell I am putting back the 80% used back into them
had to quote all this tom given logic for you that is bogus

siberianhusky
05-17-2012, 10:49 AM
IF you batteries are getting hot AND they are "50c" packs then either there is something wrong with the boat (don't think so because it runs) or the batteries are junk.
You are drawing amp spikes of not much over 100 amps and average of 60-70 most likely.
My other spec cat see spikes of about 110 and an average of about 75. It's a butt load faster than my MC!
A quality 25c 5000mah pack can run this without overheating the packs. In fact I have run this setup with a pair of 25c 5000mah Enerland packs with no heat problems at all. Not ideal but very,very possible. I have the eagletree data available.
Since nothing has gone up in smoke I'd have to say your packs are no good because they don't seem to be able to deliver 100 amps without heat issues.
Or you are running them down too far.
I completely agree with the 3.7v number, thats my baseline as well. With my Crew thats about 4 minutes hard non stop running with a 5000mah setup, resting voltage before I charge is always 3.7x V. Also works out to an approximate amp draw of 60 amps.

Brushless55
05-17-2012, 10:51 AM
IF you batteries are getting hot AND they are "50c" packs then either there is something wrong with the boat (don't think so because it runs) or the batteries are junk.
You are drawing amp spikes of not much over 100 amps and average of 60-70 most likely.
My other spec cat see spikes of about 110 and an average of about 75. It's a butt load faster than my MC!
A quality 25c 5000mah pack can run this without overheating the packs. In fact I have run this setup with a pair of 25c 5000mah Enerland packs with no heat problems at all. Not ideal but very,very possible. I have the eagletree data available.
Since nothing has gone up in smoke I'd have to say your packs are no good because they don't seem to be able to deliver 100 amps without heat issues.
Or you are running them down too far.
I completely agree with the 3.7v number, thats my baseline as well. With my Crew thats about 4 minutes hard non stop running with a 5000mah setup, resting voltage before I charge is always 3.7x V. Also works out to an approximate amp draw of 60 amps.

sounds about right.. :tiphat:

xlandguy
05-17-2012, 11:00 AM
there is some good info here. But I agree that we don't need to be calling anyone a moron. C'mon now. I would say that most packs will get "warm" running in a high performance FE boat. I run 25c 5,000mah from SPC and 40c 4,400mah packs by Sky Lipo. Both seem to get a bit warm but not of concern. I have 4 more batteries on order, these are Zippy 45c 5,000mah packs. $27 bucks a pack, what a price.

siberianhusky
05-17-2012, 11:55 AM
One other thing is C rating is not tied to how much capacity is left in the pack, It is simply how much amperage the pack is capable of delivering. It can still put out 120 amps or whatever and only have 1500mah left in the battery, it just will not do it for very long before the pack is at 0.
If it actually worked the way you think it does we'd all be destroying equipment on every run.

If you do the math, An 8200mah 30C pack that has been run down to %20 capacity now has 1600 (approx) mah remaining. 1.6X 30 = 48amps... thats what the math says.

Math may be right but the logic behind this is just plain old wrong! It just doesn't work this way. IF you are quoting your battery guy right I think you need to listen to some other people as he has no clue what he's talking about, as long as you are really stating his position and not what you think you understand. That pack would keep putting out 246 amps if so loaded until it's dead. It's a function of battery construction not capacity. Although capacity IS part of the equation, just not as a variable, it's set and doesn't change due to the state of a charge. A 8200mah battery is an 8200mah battery if it's fully charged or completely flat it's potential capacity is the exact same 8200mah.

Brushless55
05-17-2012, 12:13 PM
One other thing is C rating is not tied to how much capacity is left in the pack, It is simply how much amperage the pack is capable of delivering. It can still put out 120 amps or whatever and only have 1500mah left in the battery, it just will not do it for very long before the pack is at 0.
If it actually worked the way you think it does we'd all be destroying equipment on every run.

If you do the math, An 8200mah 30C pack that has been run down to %20 capacity now has 1600 (approx) mah remaining. 1.6X 30 = 48amps... thats what the math says.

Math may be right but the logic behind this is just plain old wrong! It just doesn't work this way. IF you are quoting your battery guy right I think you need to listen to some other people as he has no clue what he's talking about, as long as you are really stating his position and not what you think you understand. That pack would keep putting out 246 amps if so loaded until it's dead. It's a function of battery construction not capacity. Although capacity IS part of the equation, just not as a variable, it's set and doesn't change due to the state of a charge. A 8200mah battery is an 8200mah battery if it's fully charged or completely flat it's potential capacity is the exact same 8200mah.


Yes!
Another thought I had, if this all was true then my 3D planes could not 3D anymore when my packs got below 40% capacity, and I run them down to 20%.. I would not have enought amps to hang on the prop like I can at 20%

DjFlipNautikz
05-17-2012, 09:14 PM
So you get what, 10 mins runtime with the two 4s in parallel? Motor must get kind of hot running that long? And it looks like its going pretty good even with the added weight of all that battery!

i always check my temps after a run. and i always run until the LVC kicks in. My temps are usually 100* - 110*F.

they really dont get that hot.

i like the extra weight of the batteries and i go as fast as my buddy with an MC just like mine but he runs two 2s batteries in series.

And also i would listen to these guys...they know their :censored:

good luck man!!

xlandguy
05-18-2012, 08:30 AM
And also i would listen to these guys...they know their :censored:

good luck man!!
That fo sure!

Old Sloppy
05-19-2012, 08:51 AM
i always check my temps after a run. . My temps are usually 100* - 110*F.

they really dont get that hot.



Did you know that Lipo's like to be over 100 degrees F ?

In fact 122 degrees F is the target tempature, for best perfomance.

Actually Lipo's hate to be below 100 degrees F, except when in "storage mode" then they like 45 degrees F.

Harry

Brushless55
05-19-2012, 10:44 PM
But I'm new to boats. So clearly I don't know anything about RC electronics right.

For the record, 3.4 volts per cell is empty. at 3.6 volts per cell I'm putting about 4000mah back into my 5000mah packs when I charge. By my calculations, thats %20 remaining.

:blink:


most pack are about done at 3.6v per cell.. you might have about 10% left in the packs
all my packs when they are at about 3.7v per cell I am putting back the 80% used back into them
had to quote all this tom given logic for you that is bogus

LOL... this picture says alot
just had to find this :tiphat:
http://i703.photobucket.com/albums/ww39/filmmaker2009/Fuel.gif

bdp1174
05-23-2012, 08:56 PM
Well I tried your suggestion on moving the packs further back and it helped a ton.I lowered the strut back to around the factory position and it seemed to be running pretty fast.I will probably try bringing the strut up a bit,but it seemed faster already.Here is a quick video of how it ran after moving the batteries,this is on 2 gens ace 5300 30c lipos on a grim 42x55.

https://www.youtube.com/watch?v=skpKmo0nCeA&feature=youtube_gdata_player

https://www.youtube.com/watch?v=P10UOV0YAYI&feature=youtube_gdata_player

Sorry for the bad view from phone but my cameraman did not flip camera to get widescreen view.

Brushless55
05-24-2012, 01:08 AM
Looks good to me man!
can you get a picture of where your stut is now?
thanks

Old Sloppy
05-24-2012, 09:25 PM
Looks like you have it well trimmed, any further adjustments will be "Extra Fine Tuning"....remember:

the further back the batteries, the higher the bow (nose)

the higher the strut, the lower the bow.

a three blade prop will lift the bow, as compared to a two blade prop will lower the bow.

in my opinion; you want the batteries slammed back as far as possible, then raise the strut as high as possible ( this is how you set the bow height/angle of attack)remember strut too high will drop the bow , run a 3 bladed prop with a "M" blade shape. 3 blade prop will allow a higher strut setting than a 2 blade..

Harry

pavmentsurfer
05-28-2012, 11:45 PM
Looks like you have it well trimmed, any further adjustments will be "Extra Fine Tuning"....remember:

the further back the batteries, the higher the bow (nose)

the higher the strut, the lower the bow.

a three blade prop will lift the bow, as compared to a two blade prop will lower the bow.

in my opinion; you want the batteries slammed back as far as possible, then raise the strut as high as possible ( this is how you set the bow height/angle of attack)remember strut too high will drop the bow , run a 3 bladed prop with a "M" blade shape. 3 blade prop will allow a higher strut setting than a 2 blade..

Harry

Man, where were you when I was trying to set up my boat. This is EXACTLY the info I had been looking for all along. It confirms what id done anyway but knowing what direction changes will take the boat is SO helpful.

I finally got the boat back home. (it was in my parents trailer while they were on holidays, they got home tonight) and I installed my Turnigy 120amp ESC and got it setup with my Traxxas TQI radio. I also installed the temp and voltage sensor the LINK app on my iPhone. It works pretty slick. Shows exactly how much voltage my 2 packs have combined. I can set alarms to go off at certain points as well and at multiple levels. Which is good because the highest I can set the LVC on the Turnigy ESC is 3.4VPC.

I also decided to TRY another motor I have here. Its an EZrun 4068 series 2700kv 4 pole. Its a big motor compared to the stock 36mm motor that comes in the MC. I have a Lepoard water jacket on it... I'm going to run it tomorrow and see how it does. If the boat runs like crap or if its just not right ill go back to the stock motor as I really had no complaints about it. I just thought id try this one for fun.

I also installed an SV27 rudder with the extra water pickup. So, I now cool the ESC from the stock pickup and the motor from the rudder... or the other way around... I can remember. Here are the pics just for fun.

http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/DSC02489.jpg
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/DSC02490.jpg
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/DSC02494.jpg
http://i844.photobucket.com/albums/ab7/pavmentsurfer/Motley%20Crew/DSC02491.jpg

Its alot of water line... but the way the Turnigy ESC has its cooling inlet and outlet (on the same side) there really weren't alot of options. I think its an O.K. job of cleaning it up but will having alot of line cause any issues with cooling? Do you think having double pickups will help keep things cooler than a single pickup?

xlandguy
05-29-2012, 12:52 AM
Looks like you have no space between drive dog and strut? I like the dual cooling, if an inlet gets blocked at least only one component overheats, not both. What's the blue thing in front of prop nut?

Grimracer
05-29-2012, 10:29 AM
Xland looks to be right.. you need to move the shaft back..

Also..all that money spent, motor, controller, whatnot and the prop has not been sharpend.... :confused2:

Might want to sharpen that prop.

Grimracer

pavmentsurfer
05-29-2012, 01:37 PM
I tried to buy a sharpened prop... but couldn't find one in stock with shipping to canada. Ive never done it before and didnt want to screw it up. I know to do it right I need a balancer as well. So I'm on the lookout for one. The prop and rudder need to be sharpened... I know :unsure:

The drivedog/strut spacing is all an optical illusion. Theres about 1/8... maybe a bit more between them. In the pic it just looks like there isnt. Is that too much.

The ESC I bought just for the LVC... but the motor was one I just had laying around I think I have less than $20 into it and $10 into the water jacket. Figured id try it. If its not ideal ill go back to the stock one. This motor is 1/3 high KV than stock so I have to think there will be some sort of cause VS effect with that drastic a jump. I could run it on 3S and STILL get higher RPM (theoretical of course) than the stock motor on 4S. Would there be any benefit to that or will it not work or translate the way I'm thinking?

pavmentsurfer
05-29-2012, 02:49 PM
Well... that didnt last long. I found a few minutes to get out with this setup this afternoon and in 7 passes the ESC literally popped and blew orange goo all over the inside of the boat. I guess the 120 amp ESC wasn't enough to handle the motor. I guess I should try the 180amp. The boat was STUPID fast... and the motor didnt seem to get overly hot in the short time I ran it. The boat is going to need some handling tweaks before i can run it WOT though. It gets really squirrely and starts to hop really bad but when its settled it takes off like a rocket.

I think I'm going to order the 180 amp ESC and see how that works. any suggestions on brand? I know the 180's have dual inlet and outlet cooling pickups so I should be able to get rid of some of my cooling hose.

xlandguy
05-29-2012, 04:08 PM
Dang, I'm just going to bite the bullet and buy a Castle Hydra, I hope that will be sufficient for whatever I want to run on.

Old Sloppy
05-29-2012, 09:25 PM
Get the Castle with the "Data Logging" it will really open your eyes as to just what is going on inside your hull.

You allso need a "Castle Link", my Castle XL2 ESC came with a coupon for a free Castle Link, you will need a usb wire however.

Harry

xlandguy
05-29-2012, 10:01 PM
Already have the Castle Link, I use it with the Castle BEC in my highly upgraded Summit 4X4 RC truck. So that will be a great feature, the data logging. I love that kind of stuff. Just thought I would use this also as a chance to show off my highly upgraded Summit, lol. 77643

Brushless55
05-30-2012, 12:07 AM
Dang, I'm just going to bite the bullet and buy a Castle Hydra, I hope that will be sufficient for whatever I want to run on.

IMO
don't waste your good cash on that
spend only 50bucks for something good!
http://fightercatracing.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=230&category_id=48&option=com_virtuemart&Itemid=1

xlandguy
05-30-2012, 08:09 AM
Those are a good upgrade over the stock Aquacraft 60amp? Thanks for the link, this could save me alot of dough!

Brushless55
05-30-2012, 03:15 PM
Those are a good upgrade over the stock Aquacraft 60amp? Thanks for the link, this could save me alot of dough!

right on man!
saving cash on a esc that works great leaves more cash for lipos = more fun time

xlandguy
05-30-2012, 06:31 PM
I really would like to add a mono hull to my RC "collection", which right now is just my MC and a Summit.

Brushless55
05-30-2012, 08:24 PM
I really would like to add a mono hull to my RC "collection", which right now is just my MC and a Summit.

http://www.aquacraftmodels.com/boats/aqub24-revolt30/index.html

D for Dummy
05-31-2012, 04:54 PM
I love my GrimRacer 2s 5000mah Lipos but I recenty bought 4 packs from larry's Performance. I bought 2s 6000mah 35c and WOW they not only last 3+ minutes longer but there is more power and higher RPM. I'm shocked and did not expect this. The roostertail is clearly much high and much longer than my GR. They were $49.95 as opposed to the GR at $77.99 each. so, lets see how long they last and well they continue to preform. :-)

RCnerd
07-08-2012, 11:59 AM
Hi Guys,
I have been following this thread as I am tryin to set up my MC for maximum performance. I have learned a lot from this thread, thanks.
Can you guys tell me what you mean when you say set your CG % first before anything else? I assume you mean Center of Gravity but I want to be sure. If this is correct.... How do you set it?

THANKS!!!

Old Sloppy
07-09-2012, 08:18 PM
Move your batteries toward the back (transom).
tecknicaly it is not C.G.
it is P.O.B. (point of ballance)
But Who Cares ????

Harry

Old Sloppy
07-09-2012, 08:21 PM
lets see how long they last and well they continue to preform. :-)

Make sure you "storage charge" them each and every time. Do Not let them sit fully charged, you will be sorry if you do....

Harry