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macr0t0r · Dec 03, 2008, 01:34 AM

Finished ATTF #73. Comments!

=== The chore of heli maintenance ===
Yes, the collective-pitch helis require a bit more love to kept them flying. However, that's part of the love! When I heard Jamie talking of balancing, trimming, tightening, lubing, aligning...well...I almost started drooling. (Yes, we're a sick breed. Chris and James understand!)

=== Blade 400 ===
@ Diggs: Excellent choice with the Blade400! It IS a noisy beast, but I like how the cyclic feels. It's more linear and less twitchy than a T-Rex. Don't worry, it's WAY smoother than the Blade CP (you already know that). Make sure you lube the belt, as it's pretty stiff.

=== Prop-balancing technique ===
I'm sure there's pros and cons to sanding versus CA, but I prefer sanding. CA doesn't still well to APC props, and if a glob collects while drying, it can alter the airflow or eventually chip off as a projectile. It's best to sand the leading edge, since that is suppose to be partially blunt anyways.

=== Inrunner versus Outrunner ===
Once again, more great stuff from the Power corner! Everything he said was dead on. There's a couple more traits to consider:

Inrunners:
1. Easier to cool since the windings are on the can. This can be important for cowled motors or some helis.
2. Reduced switching loss. Even with a 5:1 gearbox, a 2-pole inrunner will be "switched" fewer times per prop revolution than a standard 14-pole outrunner. Granted the loss is small, but it becomes more critical at high rates. This is one of the reasons why I never understood high-kV outrunners.

Outrunners:
1. QUIET. No gear noise. Perfect for those early-morning neighborhood flights.
2. Cheaper. I'm not sure why, but an outrunner always seems to be cheaper than the equivalent-sized inrunner. When you include the price of a gearbox with the inrunner, the outrunner becomes a bargain.

Also, not all outruners have the wires coming out of the face. Some have the solid plate and wires out of the back, and the prop is mounted to the rotating can up front.

Speaking of motors, NICE December giveaway! Time to donate!

Thanks again, guys!

- Jim

Dec 03, 2008, 01:34 AM	#663
macr0t0r Got more toys than my kid Join Date: Sep 2004 Location: Fremont, CA Posts: 3,390	Finished ATTF #73. Comments! === The chore of heli maintenance === Yes, the collective-pitch helis require a bit more love to kept them flying. However, that's part of the love! When I heard Jamie talking of balancing, trimming, tightening, lubing, aligning...well...I almost started drooling. (Yes, we're a sick breed. Chris and James understand!) === Blade 400 === @ Diggs: Excellent choice with the Blade400! It IS a noisy beast, but I like how the cyclic feels. It's more linear and less twitchy than a T-Rex. Don't worry, it's WAY smoother than the Blade CP (you already know that). Make sure you lube the belt, as it's pretty stiff. === Prop-balancing technique === I'm sure there's pros and cons to sanding versus CA, but I prefer sanding. CA doesn't still well to APC props, and if a glob collects while drying, it can alter the airflow or eventually chip off as a projectile. It's best to sand the leading edge, since that is suppose to be partially blunt anyways. === Inrunner versus Outrunner === Once again, more great stuff from the Power corner! Everything he said was dead on. There's a couple more traits to consider: Inrunners: 1. Easier to cool since the windings are on the can. This can be important for cowled motors or some helis. 2. Reduced switching loss. Even with a 5:1 gearbox, a 2-pole inrunner will be "switched" fewer times per prop revolution than a standard 14-pole outrunner. Granted the loss is small, but it becomes more critical at high rates. This is one of the reasons why I never understood high-kV outrunners. Outrunners: 1. QUIET. No gear noise. Perfect for those early-morning neighborhood flights. 2. Cheaper. I'm not sure why, but an outrunner always seems to be cheaper than the equivalent-sized inrunner. When you include the price of a gearbox with the inrunner, the outrunner becomes a bargain. Also, not all outruners have the wires coming out of the face. Some have the solid plate and wires out of the back, and the prop is mounted to the rotating can up front. Speaking of motors, NICE December giveaway! Time to donate! Thanks again, guys! - Jim Last edited by macr0t0r; Dec 03, 2008 at 09:00 AM.