Scratching the Baby

[basslord1124]

Saw the video earlier this morning. Man she's quick! If the motor was hot I would look at stepping down in prop size. Or it could be going bad like @jpot1 said. Do you have a watt meter? If so, use it to see what's going on. Or maybe check for any sort of resistance, rubbing against the firewall, etc.

 

[buzzbomb]

nice flying buzzbomb - how do you do the rollovers?

They're really easy. It's just an aileron roll and then up elevator when it's gear up. In practice you don't really have to think about it (which is why I can do it ), it's more like doing the roll and then pulling out so you don't crash.

 

[buzzbomb]

@buzzbomb - I use that exact same motor, esc size and 1300 3s with no problem but I use a 9x6 prop. That motor should be fine on a 10” prop as well. I use two of those motors with 10x4.5 props on my A-10. I wonder if the motor is going bad - perhaps a bearing issue? If you spin it by hand does it still spin smoothly or grind a bit?

I've got another of the same motor where I put a screw in the winding and it grinds a bit. That one spins just fine, though.

 

[buzzbomb]

Saw the video earlier this morning. Man she's quick! If the motor was hot I would look at stepping down in prop size. Or it could be going bad like @jpot1 said. Do you have a watt meter? If so, use it to see what's going on. Or maybe check for any sort of resistance, rubbing against the firewall, etc.

Yeah, for a biplane, she'll get up and go.

I can use a multimeter. What am I checking for and between which connections?

 

[basslord1124]

Never tried it with a multimeter BUT it should be fine. Basically it'll go between the battery and ESC. Charge your battery up all the way and then run it at full throttle (prop on too) for a few seconds until the sound sort of levels off (hard to explain but you'll know if it if you listen...usually takes 3-4 seconds). You can measure all sorts of different things but I would look at amps. See if your amps are exceeding your motors ratings (looks like your max is 18A). If you notice it getting there quickly before going wide open then I'd back off and try a smaller prop. No sense burning your motor up.

Think I am using the same motor in my Seaduck. I use 9x45 props in it and don't think I've had any issues with temp. Prop size can make a difference. Had the same issue with my mini Scout early on. 6" prop made the motor pretty hot to touch, 5" was barely warm.

 

[buzzbomb]

Never tried it with a multimeter BUT it should be fine. Basically it'll go between the battery and ESC. Charge your battery up all the way and then run it at full throttle (prop on too) for a few seconds until the sound sort of levels off (hard to explain but you'll know if it if you listen...usually takes 3-4 seconds). You can measure all sorts of different things but I would look at amps. See if your amps are exceeding your motors ratings (looks like your max is 18A). If you notice it getting there quickly before going wide open then I'd back off and try a smaller prop. No sense burning your motor up.

Think I am using the same motor in my Seaduck. I use 9x45 props in it and don't think I've had any issues with temp. Prop size can make a difference. Had the same issue with my mini Scout early on. 6" prop made the motor pretty hot to touch, 5" was barely warm.

My multimeter maxes at 10amp DC. Being able to track amperage draw when there's a problem would be really nice. I'm going to look into getting an ammeter or building a rig using an automotive gauge (should be relatively simple.)

 

[sundown57]

My multimeter maxes at 10amp DC. Being able to track amperage draw when there's a problem would be really nice. I'm going to look into getting an ammeter or building a rig using an automotive gauge (should be relatively simple.)

I built this one. it tells me not only the amp draw but also how many oz thrust. that way I can figure out what combo of motor and prop gives me the most output for the least input.

 

[basslord1124]

That's pretty awesome @sundown57 .

@buzzbomb ...if you got the materials go right ahead. Sounds neat. Don't sink too much money though if you do, just b/c a wattmeter will only run about $15-$20.

 

[mayan]

I built this one. it tells me not only the amp draw but also how many oz thrust. that way I can figure out what combo of motor and prop gives me the most output for the least input.

That's really cool!