need some advice for a novice re: King motor rc camera car

don lee

Member
Messages
5
Hi all, I am a camera operator and need some help with a project to film pandas in the wild. I bought a used King motor RC camera car from B and H and rigged it with a remote camera head, so all good there, rc car is working fine. I know zip about RC except what i have learned using drones.
two issues:
is there a way to beef up the battery life? It came rigged with two 5500 amp 40C 14.8v 81.4wh King motor batts and they work OK but I may need to sit idle for a couple of hours or more then back the car out of the wildlife preserve. also, will need to be able to fly overseas with these batts o they cant be too heavy duty (the airlines hate LIPO as it is) so will need to hand carry them. I have encased the car in sheet metal so the pandas cant get to the LIPOS and eat them which would def be a career ender.
also, the car wants to roll back or forward when in idle on an incline so its going to be a problem if i want to park it on a hill and hold the position. is there a way to trim the controls to deal with this?
thanks all in advance
 

Seandonato73

Well-Known Member
Messages
1,744
So advice would be to look for bigger MAH batteries. They will last longer. I have been using gens ace batteries for my electric vehicles. I have been very happy with them. There are many other good brands out there as well. A Google search for bigger batteries at your needed voltage should yield good results. As to your rolling issue you may he able to use a drag brake setting in your esc (if it has it) or some sort of mechanical brake system. The only down side to either is they will put some load on your electrical system.
 

don lee

Member
Messages
5
So advice would be to look for bigger MAH batteries. They will last longer. I have been using gens ace batteries for my electric vehicles. I have been very happy with them. There are many other good brands out there as well. A Google search for bigger batteries at your needed voltage should yield good results. As to your rolling issue you may he able to use a drag brake setting in your esc (if it has it) or some sort of mechanical brake system. The only down side to either is they will put some load on your electrical system.
Thanks for that but not up to speed on the batteries and it’s a bit confusing ( why can’t they just put the # of cells on the battery ?)
Are you saying I can get higher amp hour batts with the same voltage and it will work?
Does the watt hour need to be the same ?
Thanks !
 

Seandonato73

Well-Known Member
Messages
1,744
Ok so they are rated in miliamp hour. So you have 5500MAH (miliamp hour) your C rating is your continuous amp draw rating as they came with I would assume they are rated high enough. So look for a minimum of a 40C rated battery. Finally they are 14.8 volt or 4S. Which means there are 4, 3.7 volt batteries in series. So from a quick search I've found
https://www.gensarespammers.de/hardcase-lipo?capacity=233&voltage=148
These are hard case batteries
https://www.gensarespammers.de/4s?voltage=148
These are soft case batteries. The soft case batteries seem to have higher mah but the hard case offers a bit more protection. Which may he a moot point since your car is already armored. I'll look for some more options when I get a chance. It would be nice to see some pics so we know what were dealing with and some dimensions of the battery compartments. Normally higher capacity batteries are a bit bigger.
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/153459121698
 
Last edited:

Thrasher

Well-Known Member
Messages
485
Get aquainted with Lipo technology https://www.gensarespammers.com/bw
Get hold of two 10.000Mah batteries and put them in parallel. Or two 20.000mah batteries. You are not going for speed so C rating is not that important to you.

To put them in parallel you MUST HAVE TWO OF THE SAME BATTERY. Same volt same capacity.

You need a harness like this
https://hobbyking.com/en_us/xt60-harness-for-2-packs-in-parallel-1pc-2.html?___store=en_us

You are going to have to macgyver a handbrake system. The challenge if you use a servo to lock the break is that the servo makes noise. So maybe a servo that pushes a pin into a hole drilled into the break disc and which can pull it back out. Again, you are not going for speed so the breaks can take one for the team and still work ok. The servo can be hooked up to an unused channel on your remote, if you have one and be activated from the remote. Or you could file square teeth into the break disc and make a system like the winch on a an old castle drawbrige, I don't know what they are called in english. A peg hooks into the teeth and lock the whole drivetrain on the RC in place. It would have to be a fairly strong servo to pull it back out when there is resistence from the weight of the vehicle on the winch.

edit. Remember to get a lipo bag. They can tolerate if the battery ignites without burning. If you want a hardcase battery in a protected shell at 10.000mah you are out of luck. I remember seeing one on an RC news site about 6 months ago. High C rating 10000mah for racing. But I cant find the battery via google. I came upon this, though.

https://www.venompower.com/collections/lipo-car-truck-buggy-batteries/products/traxxas-x-maxx-rc-monster-truck-50c-4s-9000mah-14-8v-lipo-battery-by-venom

Have you noticed this?
Due to recent changes in Federal shipping regulations, the sale of lithium batteries is restricted to North America. Lithium batteries can only be shipped via ground.
 
Last edited:

Seandonato73

Well-Known Member
Messages
1,744
Hes still gonna need a minimum c rating for what ever amp load he has. Guess he'll have to see what its gonna draw for max amps.
Good idea on the mechanical lockup for the brakes. Didnt think of that.👍
Found this on kings sight. Has one based off a baja and another based off a 5ive t. Either one specs a 5500 mah 4s 30c battery. So imo he shouldn't go below 30c.
https://www.kingmotorrc.com/camera-cars/
Get aquainted with Lipo technology https://www.gensarespammers.com/bw
Get hold of two 10.000Mah batteries and put them in parallel. Or two 20.000mah batteries. You are not going for speed so C rating is not that important to you.

To put them in parallel you MUST HAVE TWO OF THE SAME BATTERY. Same volt same capacity.

You need a harness like this
https://hobbyking.com/en_us/xt60-harness-for-2-packs-in-parallel-1pc-2.html?___store=en_us

You are going to have to macgyver a handbrake system. The challenge if you use a servo to lock the break is that the servo makes noise. So maybe a servo that pushes a pin into a hole drilled into the break disc and which can pull it back out. Again, you are not going for speed so the breaks can take one for the team and still work ok. The servo can be hooked up to an unused channel on your remote, if you have one and be activated from the remote. Or you could file square teeth into the break disc and make a system like the winch on a an old castle drawbrige, I don't know what they are called in english. A peg hooks into the teeth and lock the whole drivetrain on the RC in place. It would have to be a fairly strong servo to pull it back out when there is resistence from the weight of the vehicle on the winch.

edit. Remember to get a lipo bag. They can tolerate if the battery ignites without burning. If you want a hardcase battery in a protected shell at 10.000mah you are out of luck. I remember seeing one on an RC news site about 6 months ago. High C rating 10000mah for racing. But I cant find the battery via google. I came upon this, though.

https://www.venompower.com/collections/lipo-car-truck-buggy-batteries/products/traxxas-x-maxx-rc-monster-truck-50c-4s-9000mah-14-8v-lipo-battery-by-venom

Have you noticed this?
Yeah flying with lipos has become a chore. Last I knew they had to go in your carry on luggage. That may have changed as I haven't flown in about a year or so
 
Last edited:

crucialRC

Well-Known Member
Messages
1,020
Location
Maryland, USA
If he's going to use a mechanical brake, just set it for max brake at rest position. That way the servo isn't working to keep brakes while waiting for the perfect pic. Then as he starts to drive the mechanical brake is released.
 

don lee

Member
Messages
5
If he's going to use a mechanical brake, just set it for max brake at rest position. That way the servo isn't working to keep brakes while waiting for the perfect pic. Then as he starts to drive the mechanical brake is released.
here is a couple of photos, as you can see the battery compartment is tight. which brings up another question:
i am going to attach a small peilican (hard shell) case to the circular platform that forms the camera base. it will hold the batts for the camera and video control system and associated electronics, can i safely put the LIPOS in there as well? i would need to extend the battery leads but only by 6 inches so wouldnt be much line loss. this would make it much easier to change the LIPOs.
also, the photos only show a mockup of the armour and cammo i will be using.
thanks
here is a couple of photos, as you can see the battery compartment is tight. which brings up another question:
i am going to attach a small peilican (hard shell) case to the circular platform that forms the camera base. it will hold the batts for the camera and video control system and associated electronics, can i safely put the LIPOS in there as well? i would need to extend the battery leads but only by 6 inches so wouldnt be much line loss. this would make it much easier to change the LIPOs.
also, the photos only show a mockup of the armour and cammo i will be using.
thanks
sorry, one last thing. I assume the mechanical brake is an add-on i can purchase on line?
 

Attachments

don lee

Member
Messages
5
thanks to everyone for your responses. i will dig in and get some stronger batts.
 

Thrasher

Well-Known Member
Messages
485
sorry, one last thing. I assume the mechanical brake is an add-on i can purchase on line?
No. You are going to have to invent one. I gave you a couple of ideas and crucial improved upon them with his idea. I think the whole market for people who need a manual handbrake for their RC is one. Not one percent. One. Its you.
 
Top