brushless 1/5 4wd conversion about to begin! couple questions.

[KaztheMinotaur]

I bent a hook on the end of a straightened coat hanger and hung the gear on it. My mechanic heated it up with the torch to cherry and I dropped it into the oil.

[Ryu James]

Originally Posted by KaztheMinotaur

I bent a hook on the end of a straightened coat hanger and hung the gear on it. My mechanic heated it up with the torch to cherry and I dropped it into the oil.

just used motor oil? or new? 10w30? lol.

[KaztheMinotaur]

It was a misture of new Wal-Mart brand 10-30 and Valvoline 10-30. Thats what I had laying around.

[KaztheMinotaur]

I had to do some dremel sanding to get the hub to fit into the milled out area after the hardening? Wonder if the gear would have changed size slightly ? Or maybe it was a buildup of oil bakes on gunk ?

[Ryu James]

Originally Posted by KaztheMinotaur

I had to do some dremel sanding to get the hub to fit into the milled out area after the hardening? Wonder if the gear would have changed size slightly ? Or maybe it was a buildup of oil bakes on gunk ?

i bet it was due to buildup of the hardened coating.

my machinist made a mistake on my motor mount plates so he is making new ones today. i hope to get my motor mounted up tonight.

hey kaz,
after you heated the gear and dropped in oil did you then heat again and drop in water? didnt someone here on the forum say to do it that way? or is that necessary?

[KaztheMinotaur]

The machine shop I went to said to use oil only.

[Bondonutz]

Supposedly using the used oil will add carbon to the heat treated part.

[KaztheMinotaur]

True but there is carbon in any patroleum product.

[Ryu James]

so i had some time tonight and was able to make a little progress. the stock rampage rx box was perfect size to fit both my reciever and hydra esc. i mounted a 40mm fan on each side of the box blowing on the aluminum pipes of the esc. i think this will cool it sufficiently. the large hole where the motor leads exit should provide escape for warm air as the fans cool the esc. if it doesnt work, back to the drawing board. the esc is mounted securely inside and i could even waterproof the box with a little more work. also put 8mm bullets on esc wires.

next i am going to build a large top plate that combines the front and center top plates into one plate. this will help reduce chassis flex and will be the mounting place for this rx box. the brake and steering servo wires will just run in through one of the holes in the box. i like this configuration as it will look nice and clean when all is said and done.

just a question - why does the hydra esc not have a power switch? it only has the connector for the rx but that is it. there is no switch at all. is it supposed to be like this?

[florianz]

I really like that design! cool idea.
a center top plate will help a lot, my first one was made of carbon, but too thin and broke after a crash. I have now installed a kind of "bar" made of epoxy/gfk (as seen in my thread), that allows a little torsion but still stabilizes the car.

I've tried different positions for the esc in my buggy, try to find a place as low and front as possible, as it weights quite a bit. I've placed mine on the steering servo, w. is the best place I think.

can't wait to see your truck rollin!

[KaztheMinotaur]

It doesn't have a switch...it just turns on with the RX gets it's power. What are you doing to RX power?

I did a little work yesterday also. I'm going to run a 3S LiPo into a 3 way parallel split: BEC, fans, and lights.

I've also been tinkering around with a computer power supply. They can easily be converted to provide 3 / 5 / 12 volts to power a battery charger. You can even series 2 different ones together for any combination of the above.

[transtalon]

I think that fan is a great idea but it would not be enough to cool down the aluminum plates as when the esc heats up, it heats up real fast. It really needs a watercooling to have the 240 amp rating capability or you'll ending up with a burnt esc or a bad fire.

[RC-Monster Mike]

The CC HV boat controllers are pretty rugged even without cooling. I ran a 180HV in a Baja on 8s and 10s with no fan or cooling measures at all and it never got hotter than 120F or so. I would expect a 4wd like this to heat things up a bit more, but the controllers are pretty rugged. People abuse the crap out of these ESCs in big boats with silly voltage and huge amp spikes. High end boat racing is as hard or likely harder on electronics than land use (these 4ft plus boats going 100+ MPH through the water is way more load than this 1/5 at 50mph).

[pinkpanda3310]

Originally Posted by RC-Monster Mike

The CC HV boat controllers are pretty rugged even without cooling. I ran a 180HV in a Baja on 8s and 10s with no fan or cooling measures at all and it never got hotter than 120F or so. I would expect a 4wd like this to heat things up a bit more, but the controllers are pretty rugged. People abuse the crap out of these ESCs in big boats with silly voltage and huge amp spikes. High end boat racing is as hard or likely harder on electronics than land use (these 4ft plus boats going 100+ MPH through the water is way more load than this 1/5 at 50mph).

I was always under the impression that boating was less on the electronics 'cause it was a slightly more constant throttle than land use. So they could run higher revs for longer ( with water cooling ) and less amp spikes. Obviously, I was wrong.

Can't wait to see the final product.

[RC-Monster Mike]

When a big boat running high power hits a wave at 50+ mph and comes out of the water, the prop revs out. When the prop re-enters the water, you have a tremendous amp spike - huge load. And while the boat is in the water, the load is much more constant - as well as constantly higher load (water is constantly around the prop - boats don't coast or roll like cars, so there is always a substantial load on the system). Ever try to run in the pool? Tough to go fast due to all the drag. :)