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Thread: Venom/Atomik New 58 Inch Electric Catamaran

  1. #91
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    Quote Originally Posted by Paul Susbauer View Post
    The goal was to get the most out of these components while not stressing them. At most its pulling about 100amps continuous, through the 120 amp esc. The motor itself typically comes off the water at 130 F or less after heat soak. Motor not stressed, ESC not stressed, and even the cheap 25C packs aren't stressed.


    Paul Susbauer
    Product Manager
    Atomik-RC
    Quote Originally Posted by Brushless55 View Post
    the site claims 2000watts, and that pretty cool!
    2000watts / 6s = about 90amps
    most said to pull is 100amps continuous = about 2200watts, sweet!
    runtimes @ 90amp cont. = 2.67min
    @ 100amp cont. = 2.4min

    no one on these forums I now of runs 25c 5000mah packs pulling 90-100amps cont
    that would = some hot lipos and under powered and or stressed electronics


    someone on this forum or another talked about long or good runtimes with this cat...
    just sharing my thoughts
    Quote Originally Posted by Chris Nicastro View Post
    Hey guys,
    Its been a while since my last post and having read this thread so far I'm reminded of why I have not posted in so long.


    @ Brushless 55
    Yes by your math if you held the throttle wide open until the pack quits you would have a couple minutes of runtime. I dont refute that but in practice when you drive an RTR like this and back off in turns and drive it around we get 5-7 minutes or more. If you add more capacity you will get longer runs over 10 minutes. The 6S pack, ESC and motor temps all come off well under our safety limits or we would have not released this product.

    Chris
    Just going by what Paul said about 100amps cont.
    can't this hull take WOT turns?
    not sure how someone can more that double the runtimes by slowing a bit in the turns and yet WOT on the straights?
    but 5-7min rutimes on 5000mah packs = 34 to 48 amps cont. or about 755 to 1065 watts
    just trying to figure out the 2000watts that's being advertised by venom, because that's still only about 2.7min of runtime

    Quote Originally Posted by forescott View Post
    Just got mine yesterday
    post some pics for us!

    Quote Originally Posted by EricSchlaifer View Post
    Hi all. I'm a new Venom dealer and got a couple of the ARC's in last Friday. Ran the snot out of them all weekend! Out of the box they work fairly well. I think it will be a hit with the weekend warrior crowd. COG is a bit high with the stock battery location, I'm going to run two batteries and move them to the sponsons. I'll let everyone know how it works out. I'm also working on changing the motor out for something in the 500KV range and plan on running 12S. This big boat definitely needs more power than the stock electronics can provide. Overall I'm very pleased with the package Venom has put together and hope this boat is a sign of what is to come.
    hey welcome to OSE bro!
    snap some pics of your Cat for us, and please keep us posted of the 12s rig
    Last edited by Brushless55; 05-29-2012 at 09:17 PM.
    .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

  2. #92

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    Again if you are racing it WOT for the entire pack and not letting off then the load will be X and the run time will be Y. As we have driven it and other have as well we are experiencing longer run times than your math predicts. The load varies by throttle input and water conditions so unless your running on a perfect lake and WOT you will see the shortest run times. We test in all weather from calm to 15-20mph winds and 4-6in choppy water, best to worst case, to see how things go. The boat can handle all of that and the run times vary as such.
    Also this is a scale style hull (narrower) not a hobby race hull (wider) so you should drive this hull with that in mind, that is why you back off entering a corner and power out of the corner. You can set the hull up to drift through a corner on power if you understand boat set up.
    VENOM RACING R&D

  3. #93
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    Quote Originally Posted by EricSchlaifer View Post
    Hi all. I'm a new Venom dealer and got a couple of the ARC's in last Friday. Ran the snot out of them all weekend! Out of the box they work fairly well. I think it will be a hit with the weekend warrior crowd. COG is a bit high with the stock battery location, I'm going to run two batteries and move them to the sponsons. I'll let everyone know how it works out. I'm also working on changing the motor out for something in the 500KV range and plan on running 12S. This big boat definitely needs more power than the stock electronics can provide. Overall I'm very pleased with the package Venom has put together and hope this boat is a sign of what is to come.
    wonder what the real Watts of this system are

    Quote Originally Posted by Chris Nicastro View Post
    Again if you are racing it WOT for the entire pack and not letting off then the load will be X and the run time will be Y. As we have driven it and other have as well we are experiencing longer run times than your math predicts. The load varies by throttle input and water conditions so unless your running on a perfect lake and WOT you will see the shortest run times. We test in all weather from calm to 15-20mph winds and 4-6in choppy water, best to worst case, to see how things go. The boat can handle all of that and the run times vary as such.
    Also this is a scale style hull (narrower) not a hobby race hull (wider) so you should drive this hull with that in mind, that is why you back off entering a corner and power out of the corner. You can set the hull up to drift through a corner on power if you understand boat set up.
    what is X?
    we are being told 5000mah 25c packs are more than enough for this boat at WOT
    and we were told that is 100amps cont.. if so 25c won't cut it

    lots of racers including myself understand the water conditions effects how a boat runs and the loads on the esc/motor/batteries

    from your postings this boat can't take WOT turns so now in this thread we are reading two different out comes of this RTR
    plus runtimes are more than doubled for letting off in the turns??

    only posting some thoughts that I have and possibly others as well

    I want a big cat
    .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

  4. #94
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    I modded the coupler today to fit the 6mm shaft. I'm going to run a Scorpion 500kv outrunner in it. I'm having trouble locating a suitable HV ESC stateside. If anyone has some recomendations I would love to hear them!

    Here it is the day I unboxed it




    I just ran today with a bit more positive thrust, finally got the boat to ride on the rear pad. I will try to get someone to take some video of it the next time I'm out so everyone can see it running.

  5. #95
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    Eric, thank you for posting those pictures..
    have you tried fightercat racing?
    he has lots of HV escs to choose from..
    any idea what your CG is at?
    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

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    When you say positive thrust, do you mean the angle of the strut?

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    Quote Originally Posted by Brushless55 View Post
    Eric, thank you for posting those pictures..
    have you tried fightercat racing?
    he has lots of HV escs to choose from..
    any idea what your CG is at?
    thanks
    No problem!

    With the battery in the stock location its roughly 19 inches. I think it would probably be better around 16-17". I expect that running a 12S configuration will improve it (since the batteries will be in the sponsons).

  8. #98
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    Quote Originally Posted by forescott View Post
    When you say positive thrust, do you mean the angle of the strut?
    Haha, yes. I didn't realize how awkwardly I worded that until I just reread it.

  9. #99
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    Quote Originally Posted by EricSchlaifer View Post
    No problem!

    With the battery in the stock location its roughly 19 inches. I think it would probably be better around 16-17". I expect that running a 12S configuration will improve it (since the batteries will be in the sponsons).
    I think this hull is 55" so that puts you at about 35% right now..
    and 16.5" puts ya at 30%, and that would possibly work better like you are thinking
    .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

  10. #100
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    Quote Originally Posted by Brushless55 View Post
    I think this hull is 55" so that puts you at about 35% right now..
    and 16.5" puts ya at 30%, and that would possibly work better like you are thinking
    Yea, its 55". I have already pulled the motor out of it to start the conversion for 12S. My friend has one as well and will be running 6S until he sees mine completed. I plan on running two 6s packs in parallel in the next few days so I can play with the CG and strut angle on his ARC. I realize most people who purchase this boat probably will stick with the stock electronics for awhile and I want to be able to recommend a good handling starting point.

    Just took a peak over at fightercat and that 16S 300amp ESC looks to be just the ticket!

  11. #101
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    Quote Originally Posted by EricSchlaifer View Post
    Yea, its 55". I have already pulled the motor out of it to start the conversion for 12S. My friend has one as well and will be running 6S until he sees mine completed. I plan on running two 6s packs in parallel in the next few days so I can play with the CG and strut angle on his ARC. I realize most people who purchase this boat probably will stick with the stock electronics for awhile and I want to be able to recommend a good handling starting point.

    Just took a peak over at fightercat and that 16S 300amp ESC looks to be just the ticket!
    I would try this motor as I think it's near the same as stock but a different wind at 720kv and great for 10s runs
    and only 55bucks
    http://fightercatracing.com/index.ph...emart&Itemid=1
    .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

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    I have to check the mount spacing in the morning, but that looks very nice. I also noticed there is a 520kv version as well. That's a way cheaper option than the 500KV Scorpion that I'm thinking of using. Thanks for the great suggestions!

    I couldn't wait, just checked it will fall right in!
    Last edited by EricSchlaifer; 05-30-2012 at 01:39 AM.

  13. #103
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    Get a fightercat hv esc

  14. #104
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    Quote Originally Posted by Rumdog View Post
    Get a fightercat hv esc
    Yea looked at those last night, they look perfect. The price is damn good too! Now I'm just torn over using one of the fightercat outrunners or the scorpion I was originally planning on using.

  15. #105
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    Quote Originally Posted by EricSchlaifer View Post
    I have to check the mount spacing in the morning, but that looks very nice. I also noticed there is a 520kv version as well. That's a way cheaper option than the 500KV Scorpion that I'm thinking of using. Thanks for the great suggestions!

    I couldn't wait, just checked it will fall right in!
    Right on Eric
    And I think the 1180kv version he sells is what comes in this boat (aka 1200kv)
    And again only 55bucks
    .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

  16. #106

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    Quote Originally Posted by Brushless55 View Post
    wonder what the real Watts of this system are



    what is X?
    we are being told 5000mah 25c packs are more than enough for this boat at WOT
    and we were told that is 100amps cont.. if so 25c won't cut it

    lots of racers including myself understand the water conditions effects how a boat runs and the loads on the esc/motor/batteries

    from your postings this boat can't take WOT turns so now in this thread we are reading two different out comes of this RTR
    plus runtimes are more than doubled for letting off in the turns??

    only posting some thoughts that I have and possibly others as well

    I want a big cat
    Well I'm not sure what to tell you, you'll just have to try it.

    One of our employees bought an ARC and took it home over the long weekend and reported a 14.55min run time just playing around with it in choppy and windy conditions and being cautious. He ran a new 6S 25C 5000mah pack. He is a typical newcomer to big electrics so this is an example of the type of use and run times we should see. As a customer gets confident and faster with the boat things will change.

    If you look at a data log graph when this boat is driven the peak amps hit at the pull of the trigger and taper off, its not a continuous high load. When you let off to turn the boat will coast so it reads nearly zero load and then the cycle starts again. So the added run time is from the fact that the load is not perfectly continuous coupled with the driving style you end up with more time than the straight math predicts.

    In testing the 50C packs for sure are way better than the 25C packs but the point is the boat works fine with the least expensive packs too.
    VENOM RACING R&D

  17. #107
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    Quote Originally Posted by Brushless55 View Post
    Right on Eric
    And I think the 1180kv version he sells is what comes in this boat (aka 1200kv)
    And again only 55bucks
    The boat comes with an 1100KV. I'm not sure who's making these motors for Venom, but it looks like an overgrown version of their other outrunners. The guys at Venom have told me that they are working on some factory upgrades for the motor/ESC for this boat. I'm hoping to have a good package to recomend to my customers soon. I would really like to get this boat past 50mph, but still keep a decent runtime. Right now my run times have been all over the place! Depending on the water conditions, strut angle, and driver I have seen runtimes between 5-12 minutes! Admittedly, I have a lot more real boat experience than RC boat experience. But, I was still pretty surprised to see so much variation. My friend ran his yesterday with what I felt was way too much strut angle. He had a 6 foot tall roost and would cavitate pretty badly getting on plane...had to really roll into the throttle. We did see the fastest top speed though, but the shortest run time - 5 min. It's why I'm so anxious to try to improve the CG. I also need to find my GPS. The boat did walk past his stock MG, so i'm pretty confident it is capable of 40+ out of the box.

    Are boats like similar to most other electrics where its preferable to achiever rpms with higher volts/lower kv's, or vice versa? What is that seaking 120amp esc good for kv wise in everyone's opinion?

  18. #108

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    The ARC hull is the same as the gas boats we offer so the CG position is the same if you have any experience with the gas version.
    If you set the CG up by the total length at a certain % then it will end up nose heavy. If you set the CG up with the wet hull length then the CG will be more accurate. I balance the hull at about 30mm ahead of the rear step and the hull runs pretty dry. The prop depth is aligned with the lowest edge of the sponsons, maximum. The angle is usually 0deg. and the boat runs OK like this. This hull has a good tunnel height and gets lighter with speed so depending on the days conditions you should set the drive angle and CG as needed.
    VENOM RACING R&D

  19. #109

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    Quote Originally Posted by EricSchlaifer View Post
    The boat comes with an 1100KV. I'm not sure who's making these motors for Venom, but it looks like an overgrown version of their other outrunners. The guys at Venom have told me that they are working on some factory upgrades for the motor/ESC for this boat. I'm hoping to have a good package to recomend to my customers soon. I would really like to get this boat past 50mph, but still keep a decent runtime. Right now my run times have been all over the place! Depending on the water conditions, strut angle, and driver I have seen runtimes between 5-12 minutes! Admittedly, I have a lot more real boat experience than RC boat experience. But, I was still pretty surprised to see so much variation. My friend ran his yesterday with what I felt was way too much strut angle. He had a 6 foot tall roost and would cavitate pretty badly getting on plane...had to really roll into the throttle. We did see the fastest top speed though, but the shortest run time - 5 min. It's why I'm so anxious to try to improve the CG. I also need to find my GPS. The boat did walk past his stock MG, so i'm pretty confident it is capable of 40+ out of the box.

    Are boats like similar to most other electrics where its preferable to achiever rpms with higher volts/lower kv's, or vice versa? What is that seaking 120amp esc good for kv wise in everyone's opinion?
    The KV value is not the best way to go about this, you need to measure the load. The prop choice with any motor and ESC combo will make or break the set up. So even if the guys chime in with a KV suggestion it has to come with a prop and peak Amps info to be relevant. The ESC is rated to 120A cont. and up to 6S. That peak power value is 120A X 25.2V = 3024Watts That is the combos max potential output. That amount of watts puts us at nearly twice the HP of the typical stock Zenoah 26cc engine.
    With 1100KV and the 54mm prop this combo on 6S is well matched to the 120A ESC with a margin of safety. With off the shelf components and some testing you will find a better more powerful combo for sure and go faster than the stock boat. If you test with different props you might find a little better top speed on the stock set up but you run the risk of blowing the ESC.

    No matter what you do please test with a data logger to help you zero in on a set up while seeing exactly whats going on each run. Better yet if you have telemetry.
    VENOM RACING R&D

  20. #110
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    Quote Originally Posted by Chris Nicastro View Post
    The ARC hull is the same as the gas boats we offer so the CG position is the same if you have any experience with the gas version.
    If you set the CG up by the total length at a certain % then it will end up nose heavy. If you set the CG up with the wet hull length then the CG will be more accurate. I balance the hull at about 30mm ahead of the rear step and the hull runs pretty dry. The prop depth is aligned with the lowest edge of the sponsons, maximum. The angle is usually 0deg. and the boat runs OK like this. This hull has a good tunnel height and gets lighter with speed so depending on the days conditions you should set the drive angle and CG as needed.
    Thanks Chris. I was running 0%, with the depth as you described (I have not strayed from those settings on my boat yet). It ran a tad wet for me with the battery in the stock position. I just checked CG and we are referencing the same point. I haven't confirmed it yet, but I suspect my friend had too little prop depth. And you are correct, at that point the hull is very stable. My boat got runtimes between 8-10 minutes. I had little to no cavitation, even when just stabbing the throttle. The boat planed easily too.

  21. #111
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    Quote Originally Posted by Chris Nicastro View Post
    The KV value is not the best way to go about this, you need to measure the load. The prop choice with any motor and ESC combo will make or break the set up. So even if the guys chime in with a KV suggestion it has to come with a prop and peak Amps info to be relevant. The ESC is rated to 120A cont. and up to 6S. That peak power value is 120A X 25.2V = 3024Watts That is the combos max potential output. That amount of watts puts us at nearly twice the HP of the typical stock Zenoah 26cc engine.
    With 1100KV and the 54mm prop this combo on 6S is well matched to the 120A ESC with a margin of safety. With off the shelf components and some testing you will find a better more powerful combo for sure and go faster than the stock boat. If you test with different props you might find a little better top speed on the stock set up but you run the risk of blowing the ESC.

    No matter what you do please test with a data logger to help you zero in on a set up while seeing exactly whats going on each run. Better yet if you have telemetry.
    Thanks again Chris :) I do have a receiver with telemetry that I was planning on running with when I test the new 12S combo that I am working on, still trying to decide on ESC. But, that is still very much in the research stage. A data logger is a must! I'm not a fan of blowing up gear to determine that I have pushed it too far I plan on running the boat stock while I acquire the right gear to set up 12S. The only mod i'm planning on immediatly is dual packs in the sponsons.
    Last edited by EricSchlaifer; 05-30-2012 at 12:32 PM.

  22. #112

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    For your 12S test try to target 30,000RPM at peak values and go from there.
    30000/50.4V = 595KV. With 20% losses you will see roughly 24000RPM at the prop. If you want more RPM then do the math to achieve 30000RPM after 20% losses. The trouble is with more RPM the prop size drops and the amps begin to pile on so I usually target 30000RPM after losses and adjust accordingly.
    The ARC is set up at 27720 peak RPM and roughly 22000 to 23000 rpm at the prop. I have tested smaller props and more RPM and the boat suffers getting out of the hole and on step. Once on step the speed is great and we have gone over 50mph.

    We will have a plug and play option set for 12S soon.
    VENOM RACING R&D

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    Quote Originally Posted by Chris Nicastro View Post
    Well I'm not sure what to tell you, you'll just have to try it.

    One of our employees bought an ARC and took it home over the long weekend and reported a 14.55min run time just playing around with it in choppy and windy conditions and being cautious. He ran a new 6S 25C 5000mah pack. He is a typical newcomer to big electrics so this is an example of the type of use and run times we should see. As a customer gets confident and faster with the boat things will change.

    If you look at a data log graph when this boat is driven the peak amps hit at the pull of the trigger and taper off, its not a continuous high load. When you let off to turn the boat will coast so it reads nearly zero load and then the cycle starts again. So the added run time is from the fact that the load is not perfectly continuous coupled with the driving style you end up with more time than the straight math predicts.

    In testing the 50C packs for sure are way better than the 25C packs but the point is the boat works fine with the least expensive packs too.
    your preaching to the choir on the full throttle off the throttle stuff
    100amp cont will toast a 25c pack
    and the math still does not compute with the 100amp cont WOT vs 14.55min runtimes
    you cant be off the throttle that much with a system said to deliver 2000watts and still get almost 15min rutimes while sport runing ??
    14.55min x 6s = only 16.5amps = 366watts!

    my race boats see 2.75min and maybe a little more racing and close to 4.5min max for sport running, and that's with lots of slowing in the corners and splashing my friends on the shores


    Quote Originally Posted by EricSchlaifer View Post
    The boat comes with an 1100KV. I'm not sure who's making these motors for Venom, but it looks like an overgrown version of their other outrunners. The guys at Venom have told me that they are working on some factory upgrades for the motor/ESC for this boat. I'm hoping to have a good package to recomend to my customers soon. I would really like to get this boat past 50mph, but still keep a decent runtime. I also need to find my GPS. The boat did walk past his stock MG, so i'm pretty confident it is capable of 40+ out of the box.

    Are boats like similar to most other electrics where its preferable to achiever rpms with higher volts/lower kv's, or vice versa? What is that seaking 120amp esc good for kv wise in everyone's opinion?
    the specs say 1200kv same as the FC version for much much less than venoms price
    and stick with fightercat on the electronic upgrades.. the venom stuff will be over priced vs his
    save your money on this bro


    Quote Originally Posted by Chris Nicastro View Post
    The ARC hull is the same as the gas boats we offer so the CG position is the same if you have any experience with the gas version.
    If you set the CG up by the total length at a certain % then it will end up nose heavy. If you set the CG up with the wet hull length then the CG will be more accurate. I balance the hull at about 30mm ahead of the rear step and the hull runs pretty dry. The prop depth is aligned with the lowest edge of the sponsons, maximum. The angle is usually 0deg. and the boat runs OK like this. This hull has a good tunnel height and gets lighter with speed so depending on the days conditions you should set the drive angle and CG as needed.
    every racer I know and all on these forums take mesurements from the back of the hull.. not from the rudder or stut

    Quote Originally Posted by Chris Nicastro View Post
    The KV value is not the best way to go about this, you need to measure the load. The prop choice with any motor and ESC combo will make or break the set up. So even if the guys chime in with a KV suggestion it has to come with a prop and peak Amps info to be relevant. The ESC is rated to 120A cont. and up to 6S. That peak power value is 120A X 25.2V = 3024Watts That is the combos max potential output. That amount of watts puts us at nearly twice the HP of the typical stock Zenoah 26cc engine.
    With 1100KV and the 54mm prop this combo on 6S is well matched to the 120A ESC with a margin of safety. With off the shelf components and some testing you will find a better more powerful combo for sure and go faster than the stock boat. If you test with different props you might find a little better top speed on the stock set up but you run the risk of blowing the ESC.
    uh we are many steps ahead here..
    going lower KV with more volts = more efficiency = cooler running electronics and longer rutimes
    KV value is very important for putting together a great running setup

    and one cannot compare a gas motor to a esc for power.. the motor only draws what it needs to run and no more


    Quote Originally Posted by EricSchlaifer View Post
    Thanks Chris. I was running 0%, with the depth as you described (I have not strayed from those settings on my boat yet). It ran a tad wet for me with the battery in the stock position. I just checked CG and we are referencing the same point. I haven't confirmed it yet, but I suspect my friend had too little prop depth. And you are correct, at that point the hull is very stable. My boat got runtimes between 8-10 minutes. I had little to no cavitation, even when just stabbing the throttle. The boat planed easily too.
    your at about 24 to 30 amps = 533 to 667 watts

    Quote Originally Posted by Chris Nicastro View Post
    For your 12S test try to target 30,000RPM at peak values and go from there.
    30000/50.4V = 595KV. With 20% losses you will see roughly 24000RPM at the prop. If you want more RPM then do the math to achieve 30000RPM after 20% losses. The trouble is with more RPM the prop size drops and the amps begin to pile on so I usually target 30000RPM after losses and adjust accordingly.
    The ARC is set up at 27720 peak RPM and roughly 22000 to 23000 rpm at the prop. I have tested smaller props and more RPM and the boat suffers getting out of the hole and on step. Once on step the speed is great and we have gone over 50mph.

    We will have a plug and play option set for 12S soon.
    30k taget on 12s may not be the best for a big cat like this..
    many run much lower rpms on a rig this size and get great results
    uh where is the load (peak amps) and prop sizes?


    have a great day
    .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

  24. #114
    Join Date
    May 2012
    Location
    ca
    Posts
    38

    Default

    Brushless,
    I'm probably going to head out with my buddy and his ARC today. I will time a run at WOT the whole time and let you know the run time (after I fix the prop adjustments of course).

  25. #115

    Default

    I think your mistaking or misquoting the peak value for constant value (actually average load value).The boats power system at nominal values is over 2000W etc. What you actually use to get around isn't always 2000W. The system is capable of 3000W using peak values technically but rather than use that value we understated it using nominal power.

    Running a 25C 5000mah pack at 100A continuous is under its specified limit of 125A. Is it recommended you run a battery pack under that condition...not if you don't know what your doing, period. Is that what we are saying here? No we are not. We do load test our battery packs here in house with scientific equipment and in practical test models to meet our minimum requirements. We are very well versed in LiPO usage, testing and applications.

    As for hull CG you can measure it from anywhere you want as long as you are consistent about it. It screws other people up if you use a nonstandard method but that's about it. One guys 35% can be another guys 30% as long as they know that....who cares? I measure from the transom of the wet hull. If there is an excessive overhang then you can bring other math into it and calculate moments of inertia to determine CG, do we have to split atoms here? No.

    When it comes to set up and electronics choices there are many ways you can go about that. I start with the target RPM to determine the motor to try. From experience or other data I know what ESC to try. Until I put it in the water with a data logger I always go for the smallest prop to establish a base line A/W/V reading. Then I adjust things from there.
    Can you show me how to predict amp loads in water without knowing any info before hand?

    And... umm... yes you can compare a gas engines power to a brushless system because there are mathematical relations to draw comparisons from.

    As I stated a KV value alone is not info to go on because its part of a system...need more info. like a baseline test or practical data from an identical set up, etc. He asked for just a KV recommendation only.

    Also these cats are for straight line open water style racing boats not high speed tight turns. Watch full scale or even the Europeans race with their RC 60 to 92in cats and they always slow down in the turns and power back out. The guys that race cats in ovals would not like this hull for that application. Run this ARC hull as a class and its a different story.

    Rather than pick this boat apart with your many questions and arguments lets just agree this is probably not the boat for you and move on. You race boats, thats fine, this is not a race boat like you run.
    VENOM RACING R&D

  26. #116
    Join Date
    Aug 2007
    Location
    tt
    Posts
    102

    Default solving problems is better than critique

    hi guys i read the forum what i think is why not give your expertise on a proper setup mr 55 so guys who has the boat will get it running better, thanks to you and the venom guys may seek your help on their next project.i have been in boating for over 20yrs and still learning so for the love of the sport lets all work together for the general improvement of model boating,we can share knowledge,that's what we would all want i guess, and get better run times and more speed for less price.think it's a nice project from venom/atomic and hope they keep trying.it will always have unsatisfied people but sometimes it helps improve things when looked at all possibilities.

  27. #117
    Join Date
    Oct 2008
    Location
    CO
    Posts
    9,488

    Thumbs up

    Quote Originally Posted by Chris Nicastro View Post
    1)I think your mistaking or misquoting the peak value for constant value (actually average load value).The boats power system at nominal values is over 2000W etc. What you actually use to get around isn't always 2000W. The system is capable of 3000W using peak values technically but rather than use that value we understated it using nominal power.

    2)Running a 25C 5000mah pack at 100A continuous is under its specified limit of 125A. Is it recommended you run a battery pack under that condition...not if you don't know what your doing, period. Is that what we are saying here? No we are not. We do load test our battery packs here in house with scientific equipment and in practical test models to meet our minimum requirements. We are very well versed in LiPO usage, testing and applications.

    3)As for hull CG you can measure it from anywhere you want as long as you are consistent about it. It screws other people up if you use a nonstandard method but that's about it. One guys 35% can be another guys 30% as long as they know that....who cares? I measure from the transom of the wet hull. If there is an excessive overhang then you can bring other math into it and calculate moments of inertia to determine CG, do we have to split atoms here? No.

    4)When it comes to set up and electronics choices there are many ways you can go about that. I start with the target RPM to determine the motor to try. From experience or other data I know what ESC to try. Until I put it in the water with a data logger I always go for the smallest prop to establish a base line A/W/V reading. Then I adjust things from there.
    Can you show me how to predict amp loads in water without knowing any info before hand?

    5)And... umm... yes you can compare a gas engines power to a brushless system because there are mathematical relations to draw comparisons from.

    6)As I stated a KV value alone is not info to go on because its part of a system...need more info. like a baseline test or practical data from an identical set up, etc. He asked for just a KV recommendation only.

    7)Also these cats are for straight line open water style racing boats not high speed tight turns. Watch full scale or even the Europeans race with their RC 60 to 92in cats and they always slow down in the turns and power back out. The guys that race cats in ovals would not like this hull for that application. Run this ARC hull as a class and its a different story.

    8)Rather than pick this boat apart with your many questions and arguments lets just agree this is probably not the boat for you and move on. You race boats, thats fine, this is not a race boat like you run.
    1) not my mistake, but from a Venom reps quote of 100amps cont. here on OSE..
    2000watts / 6s = 90amps and that part is cool
    reality sounds more like 50-60amps cont = 1100 to 1300watts with runtimes to follow of about 5min and that is a decent time, actually great time for a hull this size

    2) pulling a constant 100amps through a 5000mah 25c pack is very hard on it and could spell problems with constant use.. most packs are over rated and cant deliver true C rated power
    jsut saying..

    3) Who cares? well we all do on CG placement.. most if not all use the transom as the starting point when measuring for cg IMO

    4) not me but you were the one from the earlier post saying we needed loads first before we could give any advice.. just following what you said
    no way to really come up with that figure unless we put it in the water and I agree on that..

    5) uhhmmmm, not by what you posted earlier.. you cannot compare an esc rating to a gas motor...
    my P-Spec racer uses a esc rated to over 4000watts, does that mean I have almost 5 1/2hp? no not at all.. you need the motor that pulls the amps / 746 watts = 1hp
    that is not determined by the esc but the motor.. and you need like you said an esc that can take the amps adn I agree

    6) how can you get practical data with out trying something first.. kinda goes back to #4 ( a big quoted contradiction sort a )

    7) I agree these are more suited for straigh line runs vs actual racing.. I know because I owned a GAS KOS (if it's anything like that hull).. check my albums
    I agree, having 5 or more on a course and it would be a blast!!

    8) I have every right to ask all questions I want.. this is after all a free open forum!
    just reading very carefully of what is being posted by venom and others about this new boat, and things don't line up

    again have a great day.. I would love to be a high altitude tester for this boat!
    the waters are fast up here ya know!
    .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

  28. #118
    Join Date
    Aug 2007
    Location
    tt
    Posts
    102

    Default

    hi mr 55 just buy one test it if it don't work to your liking sell it. asking all the questions is your right but giving pro answers is even greater,simply put make recommendations for improvement on the boat.it don't matter who's wrong or right but getting the end results corrected.

  29. #119
    Join Date
    Aug 2007
    Location
    tt
    Posts
    102

    Default

    what's the cost of the boat and where can it be found.that would be good info to start with.

  30. #120
    Join Date
    Oct 2008
    Location
    CO
    Posts
    9,488

    Default

    Quote Originally Posted by rawsonreyes View Post
    what's the cost of the boat and where can it be found.that would be good info to start with.
    That info (link) is on the first page of this thread I think..
    .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

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