|03-02-2010, 09:03 PM||#1|
★ Site Supporter ★★ Administrator ★
I am: Max P.
Join Date: Feb 2007
Location: Aurora, Ontario
Radio of choice:
JR and Spektrum
Feedback: 20 / 100%
Total Props: 149
Scale Body Cooling
Remove this ad - become a site supporter!
I have an MX400 in a jet ranger scale body.
Prior to installing the the scale body, the heli ran at 15 amps in hover and on a 1800mah battery I got 7 minutes per flight without any problems. Battery was fine and just mildly warm.
This scale body is pretty lightweight lexan, but it has very little cooling vents.
this is waht the heli looks like now.
now the heli draws 17 amps, and based on that I should get 6 minutes.
After a few minutes of flying, the heli would drop out of the sky. It did this twice in the gym this weekend and on the second time I checked the ESC- it was smoking hot!. I suspect it overheats and cuts out, causing the heli to drop like a stone. The battery gets really hot too. On my last test flight last night, I touched the motor and it too was hot as heck.
Obviously cooling is a problem.
The only air in on top is here:
and on the bottom this is the cutout:
The MX400 main gear and auto-rotation gear have spokes that are...well, just spokes.(not like the T-rex that has little fan blades that direct cooling air into the heli)
So I would like to ask others out there for what ideas they have had for cooling.
I don't want to cut the side windows out just yet, but if I don't get any suggestions for cooling, that my have to be my next step.
By comparison, I have a T-rex in the HK Jet Ranger scale body that is also fully enclosed, and I don't have any cooling problems whatsoever with that.
The EC135 is flying on HK450 mechanics, but it does not have any side windows, and it too runs cool with no overheating.
Suggestions? Ideas? let me know.
Last edited by Max; 03-02-2010 at 09:08 PM.
|03-03-2010, 10:01 AM||#2|
RCC Pro Contributor
I am: ....Roger ..........
Join Date: Jan 2009
Location: ........Parry Sound Ont.................
Radio of choice:
# of RCs: 100
Feedback: 9 / 100%
Total Props: 12
Re: Scale Body Cooling
I don't think cooling is the whole problem though good cooling always helps .I think the greater weight on the same throttle pitch curve may be more likely,you could try to use a smaller pinnion to gear the motor for the greater weight .or reduce the pitch at a given throttle.sometimes reducing pitch does not work as well as a gear change because it requires power to spin the head faster even if it has less pitch ,a gear change improves the torque of the motor regardless. I would throw on a new pinion .Roger
|Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)|