Is this how its supposed to look when its running VIDEO

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  • xlandguy
    Senior Member
    • May 2012
    • 282

    #46
    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.

    Comment

    • siberianhusky
      Fast Electric Addict!
      • Dec 2009
      • 2187

      #47
      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.
      If my boats upside down then who owns the one I thought I was driving the last two laps?

      Comment

      • Brushless55
        Creator
        • Oct 2008
        • 9488

        #48
        Originally posted by siberianhusky
        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%
        .NAMBA20...Caterpillar UL-1, P-Spec OM29, P-Mono DF33, P-Spec JAE, Aussie 33" Hydro-LSH, Sprintcat CC2028 on 8s, PT SS45 Q Hydro, PS295 UL-1 power, OSE Brothers Outlaw QMono 4-sale, Rio 51z CC2028 on 8s

        Comment

        • DjFlipNautikz
          Member
          • Jan 2012
          • 65

          #49
          Originally posted by xlandguy
          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

          good luck man!!

          Comment

          • xlandguy
            Senior Member
            • May 2012
            • 282

            #50
            Originally posted by DjFlipNautikz

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

            good luck man!!
            That fo sure!

            Comment

            • Old Sloppy
              Harry from Atlanta
              • Jul 2007
              • 200

              #51
              Originally posted by DjFlipNautikz
              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
              60" Expresscraft SuperCat
              (2) 2028 Castle motors 64.7 mph
              10s3p with x450/3 props
              15,000 mah 40c cells,

              Comment

              • Brushless55
                Creator
                • Oct 2008
                • 9488

                #52
                Originally posted by pavmentsurfer
                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.


                Originally posted by Brushless55
                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
                .NAMBA20...Caterpillar UL-1, P-Spec OM29, P-Mono DF33, P-Spec JAE, Aussie 33" Hydro-LSH, Sprintcat CC2028 on 8s, PT SS45 Q Hydro, PS295 UL-1 power, OSE Brothers Outlaw QMono 4-sale, Rio 51z CC2028 on 8s

                Comment

                • bdp1174
                  Senior Member
                  • Apr 2011
                  • 134

                  #53
                  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.





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

                  Comment

                  • Brushless55
                    Creator
                    • Oct 2008
                    • 9488

                    #54
                    Looks good to me man!
                    can you get a picture of where your stut is now?
                    thanks
                    .NAMBA20...Caterpillar UL-1, P-Spec OM29, P-Mono DF33, P-Spec JAE, Aussie 33" Hydro-LSH, Sprintcat CC2028 on 8s, PT SS45 Q Hydro, PS295 UL-1 power, OSE Brothers Outlaw QMono 4-sale, Rio 51z CC2028 on 8s

                    Comment

                    • Old Sloppy
                      Harry from Atlanta
                      • Jul 2007
                      • 200

                      #55
                      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
                      60" Expresscraft SuperCat
                      (2) 2028 Castle motors 64.7 mph
                      10s3p with x450/3 props
                      15,000 mah 40c cells,

                      Comment

                      • pavmentsurfer
                        Member
                        • Mar 2010
                        • 84

                        #56
                        Originally posted by Old Sloppy
                        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.






                        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?

                        Comment

                        • xlandguy
                          Senior Member
                          • May 2012
                          • 282

                          #57
                          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?

                          Comment

                          • Grimracer
                            Senior Member
                            • Nov 2008
                            • 662

                            #58
                            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....

                            Might want to sharpen that prop.

                            Grimracer

                            Comment

                            • pavmentsurfer
                              Member
                              • Mar 2010
                              • 84

                              #59
                              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

                              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?

                              Comment

                              • pavmentsurfer
                                Member
                                • Mar 2010
                                • 84

                                #60
                                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.

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