Is a prop balancer required? What do they do? Shoulndn't props come ready to use?

Not usually on the trainer size 9",10 or 11. It's when you get to the 12" thru 24" props that it is req'd. I've found that the standard Master Airscrew are the most out of balance from the factory. The balance helps to prevent excessive vibration.

This is one of the "many opinion" issues with RC Flying.

Have a look at the spread of opinions by doing the search:

[link=http://www.rcuniverse.com/forum/searchpro3.asp?phrase=Prop+Balancing&forumid=ALL&p roduct=&topicreply=combined&message=subject&author =&timeframe=%3E&timefilter=0&language=single&top=3 00&criteria=AND&minRank=10&sortMethod=d&submitbutt on=+OK+]Search....[/link]
of have a look at the thread:
[link=http://www.rcuniverse.com/forum/m_1309832/mpage_1/key_prop%252Cbalancing/anchor/tm.htm#1309832]Previous thread...[/link]

gus

What about top flite props?

APC and T/F are my favorite. The wooden props will break more often on a trainer though. Till you get past the trainers, I'd stay with the cheaper Masters. The APC props will hold against flex better than most to give the best thrust.

HI LEE1 Prop balance is needed most on high rpm set ups, and large diameter props. I buy combat props by the bag full, and I don't spend more than a minute on each one. I use 120 grit paper, and a couple swipes on the heavy blade's tip makes them run smooth, and the fuel doesn't foam from vibration. I would rather shorten one of the tips by 1/16", than mess with the airfoil of one of the blades, plus you don't break into as much of the varnish on a wood prop this way. I run 21K rpm Combat engines all day with props balanced the "WRONG WAY"[taking material off one of the tips], and the bottom line is that it works, and takes less time.

I found that the APCs don't really need to be balanced.

I balanced my APC on a Chopstick and found out that it did not need to be balanced

Was that an ISO accredited chopstick?
For larger props would you move up to other forms of eating utensils or just bigger sticks?
Come to think of it the last time I got my tires aligned on my car they must have used the same method...

He he

Bigger Props = a Spoon Handle!!!

The chopstick was not ISO accredited; instead it was USDA Approved!