mprfrk440
Well-Known Member
- Joined
- Apr 14, 2007
- Messages
- 767
I transcribed the video we did at the 09 World Tunnel Champs, sent it to Grim to make sure I didn't flub anything, very good info for someone like myself that has no idea about the FE side of this hobby. Now everything I need is wish listed on my tower hobbies ID and just waiting for some $ to start.
P Spec tunnel is designed around a particular power sources. Regular 21 size tunnel boats work great, this one being a Top Speed X. Any 21 tunnel boat can be converted to FE (fast electric).
Spec Class power options:
The three power options are the Aquacraft 2030KV motor that comes in the UL-1 Superior and 60 amp esc, the AquaCraft SuperVee 1900KV and ESC, or the Black Jack 1500KV motor and esc.
What we are going to show you is basically how we have arranged the components. This arrangement was done by a fellow Team Futaba member by the name of Brian Buaas. He has been helping us with some of the stuff that we needed to get this arrangement set up. This particular boat has the UL-1 motor ESC and cooling assembly, the motor
is about $70, the cooling system about $40. The esc about $70 or so. We use a regular high power steering servo just like you would in your nitro boat and I use a tactic radio system in my boat. I also use an OS outboard lower unit, and the nice thing about this lower unit it doesn't require any special conversion kit. All I needed to do was find the drive adapter, which can be bought from somebody like Offshore Electrics or Fuller Fast Electrics. The adapters are around $10. The nice thing about the OS lower is the bolt spacing is wide enough that it goes on the edges or diameter of the motor, it makes for a real nice set up.
Poly Charger:
I use the poly charge, it will charge 4 battery packs at one time. It really it only requires 2 battery packs to get out there and really have a good time, but 4 battery packs are really ideal to get out there for a day of racing. If you're running 4 heats or so, as soon as this battery pack comes out of the boat, if you let is cool just a short period, they cool down fairly fast, you can just recharge them. Most Lipos require a charger balancer, this basically pings each cell as it is charging and charges them up equally, as these cells get out of balance you can end up with one deep discharging and possible destroying the battery pack. It's good to have a balanced charger. Maintenance on this battery it very easy, you do not have to cycle it, you don't have to discharge it, you just charge it again. What we do at work is charge them and store them charged. It will store and hold that charge, not indefinitely, but over even a couple of months. If you pulled this battery pack out of your storage container after a coupe of months, you could put it in and for the most part this boat is going to generate a much power as if you had just charged the battery. Now there are tricks to it, warming the battery up makes more power, its really not necessary. I'm not doing it here, Jerry's not, nobody pre-warming their battery packs and we are still getting really good performance out of the boats. It will run for about 5 to 5 1/2 minutes, our races are only about 2- 2 1/2 minutes long, burning just short of 3000 milli amps during a run, so we still have 2000 milli amps stored in the battery so we only need to charge 3000 back in.
ESC:
The 60amp esc which is the same one out of the ul-1 superior comes lipo ready, in other words at 12 volts this esc will start to stutter the system, it's a warning system stutter, you know it's time to bring the boat in. At 11.6 amps it shuts the power off so you don't deep discharge the battery and damage it. Just as a side note, the Super Vee esc does not have that, so you need to have some sort of voltage regulator cut off system in it or be really careful and accidentally deep discharge your battery. What I did on this esc is clip the connectors on it and made it one. The ul-1 speed control comes with two connectors on it. You can take two 2s battery pack, and basically make it a 4s battery pack, it's the same thing. We use that in our UL-1 hydroplane. It runs on the same p power but it uses two 2s battery packs instead of one 4s battery pack.
Battery Pack:
The battery that we have chosen for this boat is a 5000 milli amp 14.8 volt battery pack. Its important when you are selecting a battery pack that you strive for the largest C rating that you can, this one is 20c, they make 25c, 30c, and even 35c. This boat runs at about 55 to 60amps when it is running, you want to be about 40% below the maximum amp capability that the battery can deliver. that's a safe place to run this battery. If you ran this system at 50amps and the battery is only capable of 50amps, you can destroy the battery. that's why it is important to get high milli amp hours and a high c rating so you get a lot of amperage out of the battery. 14.8 volts is the standard power voltage for spec class racing. Can't go over that, it's what's called a 4s, or 4 cells in series. The battery pack is the biggest pill to swallow, this battery pack is about $220. The pack will last about 2 or 3 years of operation, so ultimately you can figure probably over the life span maybe $2 a run, now that is a little bit pricy, but it's in line with high nitro model boating, so really effectively this whole outfit is not that far off from a good competitive 21 tunnel boat. This boat runs just shy of 50 mph. Some of the devices that are important when this type of battery is used is the Radio box, we want to make sure we do not get it wet, now you can get it wet and it's not going to hurt things right away, but unfortunately the tabs the wires are attached to are aluminum and they will corrode and brake if you continually get this battery wet. You've got to make sure you allow it to at least dry out if you do get it wet. Avoid getting it wet. We actually have a box built for the battery pack, its basically the radio box for all the components in 3 different compartments. Put the top on and tape it up, you do have to tape it up every run, but you only need to tape up the middle compartment every time. Leave the other two taped and just pull the battery in and out as needed.
Question? If you left the battery on a slow charge would it help warm it up?
Nope! The charging systems peak on voltage and not heat. Something to keep in mind, these batteries come out of the boat after a run at about 120 degrees, totally safe, but at about160 degrees, these batteries will start to degrade. Another thing that is important with these batteries is don't get them cold. You get these batteries cold, I mean freezing or so and you use them, they lose between 5 to 8% of their capacity just off the top is gone and you can't get it back. So if your out and it's cold at the pond you can put them in an ammo container with some heater packs and towels inside to keep the batteries warm, really don't want to get them cold, but warm up to 160 degrees, pass that point is not too good for them. Actually get them to 120 degrees before you race them and there going to make their maximum power. I'm not doing that, it's not worth the risk of getting the battery pack too hot.
Prop Talk:
This battery and motor combination won't stall like a nitro boat if you have too much prop on it, it will burn up stuff. So if you over prop this thing you are going to burn something up. It doesn't give you much of a warning that you are over amping your system. It's best to really do your prop homework, start light with a propeller and work your way up. It's a good idea to have a temperature gauge and get some temp readings so you know your close. This motor runs about 110 degrees, the esc from 110 to 120 degrees. If you're over those temperatures you can potentially be over amping the system and possibly causing damage. What we've found is you can put the Eagle Tree System and put it in there and get actual numbers and this esc will handle 60 amps no problem, this one runs at about 55amps. Propeller diameter seems to be less important than propeller pitch in this case. I have a 45mm prop on here, it's a M445 and it's a big propeller, but I know it only draws about 55amps from my Eagle Tree testing, knowing that it is safe, so it's not so much the diameter of the wheel it's more of the pitch that you want to be cautious of. Some propellers even though they are smaller diameter draw way more power than the M445. The boats not necessarily any faster it's just a lot of blade efficiency in that larger diameter. We're actually allowed with this system to run large diameters which are very cool because the handling is really great.
Other than that it sets up just like your other tunnels, leg goes on steering, everything else is the same. It's very straight forward. You do have to build some type of enclosure for all of the electrical stuff but past that point everything else is the same.
Thanks Mike,
Doug
P Spec tunnel is designed around a particular power sources. Regular 21 size tunnel boats work great, this one being a Top Speed X. Any 21 tunnel boat can be converted to FE (fast electric).
Spec Class power options:
The three power options are the Aquacraft 2030KV motor that comes in the UL-1 Superior and 60 amp esc, the AquaCraft SuperVee 1900KV and ESC, or the Black Jack 1500KV motor and esc.
What we are going to show you is basically how we have arranged the components. This arrangement was done by a fellow Team Futaba member by the name of Brian Buaas. He has been helping us with some of the stuff that we needed to get this arrangement set up. This particular boat has the UL-1 motor ESC and cooling assembly, the motor
is about $70, the cooling system about $40. The esc about $70 or so. We use a regular high power steering servo just like you would in your nitro boat and I use a tactic radio system in my boat. I also use an OS outboard lower unit, and the nice thing about this lower unit it doesn't require any special conversion kit. All I needed to do was find the drive adapter, which can be bought from somebody like Offshore Electrics or Fuller Fast Electrics. The adapters are around $10. The nice thing about the OS lower is the bolt spacing is wide enough that it goes on the edges or diameter of the motor, it makes for a real nice set up.
Poly Charger:
I use the poly charge, it will charge 4 battery packs at one time. It really it only requires 2 battery packs to get out there and really have a good time, but 4 battery packs are really ideal to get out there for a day of racing. If you're running 4 heats or so, as soon as this battery pack comes out of the boat, if you let is cool just a short period, they cool down fairly fast, you can just recharge them. Most Lipos require a charger balancer, this basically pings each cell as it is charging and charges them up equally, as these cells get out of balance you can end up with one deep discharging and possible destroying the battery pack. It's good to have a balanced charger. Maintenance on this battery it very easy, you do not have to cycle it, you don't have to discharge it, you just charge it again. What we do at work is charge them and store them charged. It will store and hold that charge, not indefinitely, but over even a couple of months. If you pulled this battery pack out of your storage container after a coupe of months, you could put it in and for the most part this boat is going to generate a much power as if you had just charged the battery. Now there are tricks to it, warming the battery up makes more power, its really not necessary. I'm not doing it here, Jerry's not, nobody pre-warming their battery packs and we are still getting really good performance out of the boats. It will run for about 5 to 5 1/2 minutes, our races are only about 2- 2 1/2 minutes long, burning just short of 3000 milli amps during a run, so we still have 2000 milli amps stored in the battery so we only need to charge 3000 back in.
ESC:
The 60amp esc which is the same one out of the ul-1 superior comes lipo ready, in other words at 12 volts this esc will start to stutter the system, it's a warning system stutter, you know it's time to bring the boat in. At 11.6 amps it shuts the power off so you don't deep discharge the battery and damage it. Just as a side note, the Super Vee esc does not have that, so you need to have some sort of voltage regulator cut off system in it or be really careful and accidentally deep discharge your battery. What I did on this esc is clip the connectors on it and made it one. The ul-1 speed control comes with two connectors on it. You can take two 2s battery pack, and basically make it a 4s battery pack, it's the same thing. We use that in our UL-1 hydroplane. It runs on the same p power but it uses two 2s battery packs instead of one 4s battery pack.
Battery Pack:
The battery that we have chosen for this boat is a 5000 milli amp 14.8 volt battery pack. Its important when you are selecting a battery pack that you strive for the largest C rating that you can, this one is 20c, they make 25c, 30c, and even 35c. This boat runs at about 55 to 60amps when it is running, you want to be about 40% below the maximum amp capability that the battery can deliver. that's a safe place to run this battery. If you ran this system at 50amps and the battery is only capable of 50amps, you can destroy the battery. that's why it is important to get high milli amp hours and a high c rating so you get a lot of amperage out of the battery. 14.8 volts is the standard power voltage for spec class racing. Can't go over that, it's what's called a 4s, or 4 cells in series. The battery pack is the biggest pill to swallow, this battery pack is about $220. The pack will last about 2 or 3 years of operation, so ultimately you can figure probably over the life span maybe $2 a run, now that is a little bit pricy, but it's in line with high nitro model boating, so really effectively this whole outfit is not that far off from a good competitive 21 tunnel boat. This boat runs just shy of 50 mph. Some of the devices that are important when this type of battery is used is the Radio box, we want to make sure we do not get it wet, now you can get it wet and it's not going to hurt things right away, but unfortunately the tabs the wires are attached to are aluminum and they will corrode and brake if you continually get this battery wet. You've got to make sure you allow it to at least dry out if you do get it wet. Avoid getting it wet. We actually have a box built for the battery pack, its basically the radio box for all the components in 3 different compartments. Put the top on and tape it up, you do have to tape it up every run, but you only need to tape up the middle compartment every time. Leave the other two taped and just pull the battery in and out as needed.
Question? If you left the battery on a slow charge would it help warm it up?
Nope! The charging systems peak on voltage and not heat. Something to keep in mind, these batteries come out of the boat after a run at about 120 degrees, totally safe, but at about160 degrees, these batteries will start to degrade. Another thing that is important with these batteries is don't get them cold. You get these batteries cold, I mean freezing or so and you use them, they lose between 5 to 8% of their capacity just off the top is gone and you can't get it back. So if your out and it's cold at the pond you can put them in an ammo container with some heater packs and towels inside to keep the batteries warm, really don't want to get them cold, but warm up to 160 degrees, pass that point is not too good for them. Actually get them to 120 degrees before you race them and there going to make their maximum power. I'm not doing that, it's not worth the risk of getting the battery pack too hot.
Prop Talk:
This battery and motor combination won't stall like a nitro boat if you have too much prop on it, it will burn up stuff. So if you over prop this thing you are going to burn something up. It doesn't give you much of a warning that you are over amping your system. It's best to really do your prop homework, start light with a propeller and work your way up. It's a good idea to have a temperature gauge and get some temp readings so you know your close. This motor runs about 110 degrees, the esc from 110 to 120 degrees. If you're over those temperatures you can potentially be over amping the system and possibly causing damage. What we've found is you can put the Eagle Tree System and put it in there and get actual numbers and this esc will handle 60 amps no problem, this one runs at about 55amps. Propeller diameter seems to be less important than propeller pitch in this case. I have a 45mm prop on here, it's a M445 and it's a big propeller, but I know it only draws about 55amps from my Eagle Tree testing, knowing that it is safe, so it's not so much the diameter of the wheel it's more of the pitch that you want to be cautious of. Some propellers even though they are smaller diameter draw way more power than the M445. The boats not necessarily any faster it's just a lot of blade efficiency in that larger diameter. We're actually allowed with this system to run large diameters which are very cool because the handling is really great.
Other than that it sets up just like your other tunnels, leg goes on steering, everything else is the same. It's very straight forward. You do have to build some type of enclosure for all of the electrical stuff but past that point everything else is the same.
Thanks Mike,
Doug
Last edited by a moderator:
