AXi 5345 Overheated?
 

Help!

Trying to power sort of an "RC classic" with electricity.

121" Heinkel 219 built by Dave Platt himself 10 years ago. I suspect he got discouraged trying to fit a powerful enough banger in the little cowls

I've done a lot of bench testing and it has come down to 2 motors: Dualsky 6000 vs AXi 5345's. Both on 12S lipo's and Castle HV 160's

Both will turn a good prop (Xoar 20x12) hard enough to fly the plane (@7,000). AXi's use a little less battery, but motor case temps get up to 130 F, 140 with prolonged full throttle.

Am I worrying too much? Espirit didn't answer, don't speak Czech, so afraid to call the factory

Thanks for any help,

(Oh, there's a big pic in the basic electric forum)


mt

This temperature should be no problem.I have got a second hand model Rojeiro 140 with burnt evidense at the bottom of the fuelage of the ESC that dropped down and left black balsa marking.
The ESC was mounted with cable tiers (plastic) without a gap of air to the surfice.This is a kind of limit.The motor is a Hacker 60-series for 80 A continuous and running with a prop 20,5"x14" on 10 S.
There was only openings in the front of the cowl,but nothing to let the air get out! I have spent time to make ducts of thin balsa for suction of the cooling air.The motor has his own pair,1"x0,5" each
and the ESC about the same.The ducts inside took a little time,for sure,but now there will be little turbulens to slow down the air.The ESC (120 A HV Hobbywing) has "feet" of 0,5" to let the air flow all around.
It seems to be common practice to "forget" the outlets for kit makers to make it simple for themselves.
Moreover,the temperature is a factor getting lower power from the system for the increased resistance.
Regards; kauko "lines and rc", Gothenburg Sweden.

Thank you!

You are wellcome!
One more detail in the cooling of electric motors behind big spinners;like I have on my Tojeiro 140.I made scoops of 1/32 ply (fomed around a bottleof 1 3/4" diameter)
glueing two ply together with white glue (the water softens).They work like reversers on airplane jets building up pressure in the front end of the motor,180 degrees.
Combined with the suction from behind throuh a sleeve of thin balsa,the flow is good.Turbulunce in big sections stops much of the motion and adds to the resistance.
Cool motors for you; Kauko