Ok, so I've heard a LOT about balancing a prop and using different methods or fixing imbalances.

BUT, there was a guy at the field the other day that upon me chipping my prop, he said to trim it equally on the other side and then sand it down. Now some of what I read on balancing says NOT to touch the tip of the prop.

I'm only using a trainer, so maybe that's why the guy at the field was so leinient on his advice. But anyway, I went ahead and did it and it flew fine.

So how much does it really matter?


ALSO, having it shorter now, it is easier to land without nicking the prop. I was using a 10x6, which is now about a 9x6 Can I just swtich to a 9x6 on my .40 Hobbico Superstar?

OR, should I maybe increase the height of the wheels/landing gear? I was thinking about putting on 3.5" wheels instead of 2.5, but I was afraid of the increased drag it would cause. Should I be?

Thanks
Tim

Use your trainer prop until yo get to the LHS and get another one...it should be fine til then..When you hit a prop tip it can shreed itself pretty easily...Rog

I'm suprised there haven't been a hundred replies to the age-old question about prop balancing. Here's my 2 cents.
Yes, you want to balance your props. It helps reduce vibration. I'm kind of picky about my props and if I get a chip bigger than this "o" I just replace it. Props are pretty cheap.
Never, ever, under any circumstances trim, sand, gouge, drill, fold, spindle, or mutilate a prop in an attempt to balance it. Spray some clear acrylic or dab on some fingernail polish on the light side to balance it.
Larger wheels might help save you from a prop strike and the increased drag won't be an issue.
I'm sure I'll catch it now.

Just get A couple of master air screw props for your trainer, the things are bullet proof. I'm A total nut about my props and I have sanded them to balance if slight and used spray on them most the time. Just not too picky with trainer planes. I only use the MAS props on them and the ground strikes seems to be no big deal. A ground strike with an APC is another story and most the time it is destroyed anyway. I once trained three students with one MAS prop, it was with me as long as the plane. Once I pulled it to check the balance after countless ground strikes, it was just dandy?? I don't know how or why but it was still good?[8D] Trainers are the only planes I run Master Air Screws on and they work great.

People modify props all the time. Is it a good idea? I do not know.
In theory if you took exactly the same amount off of both ends the balance should not change very much.
Since you like the way it performs, you should measure your modified prop and pick up some replacements that are as close to that size as possible. But, don’t worry about changing props unless the one you are using breaks. Inexpensive possibilities…
Master Airscrew 9x6 $2.09
http://www3.towerhobbies.com/cgi-bin...&I=LXZ959&P=SM
Master Airscrew 9.5x6 $2.09
http://www3.towerhobbies.com/cgi-bin...?&I=LXZ962&P=7
Master Airscrew 10x6 $2.39
http://www3.towerhobbies.com/cgi-bin...&P=SM&I=LXZ965

You will get varying opinions about prop balancing, including mine. I fly 60 size trainers and sport planes with .61 two stroke or .91 four stroke engines. I use mostly Master Airscrew K Series props (the semi flexible black ones) and do not balance them. I occasionally use APC, or Master Airscrew Scimitar, props and they also go on straight out of the package. So far I have not experienced any vibration issues.

if your loosing a 1/2" on the tip of your prop, then you should replace it, just sanding the tip to match the length is no garentee that the prop will be even close to balanced,and can mess with the berings or bushings whichever your engine has in it.

that being said I am with carrellh most of the engines I have are 46 2strokes and 91 4strokes and I hardly ever bother with balancing them out of the bag larger props its a good idea.

somthing to think about if your prop has hit the ground hard enough to loose that much tip then there is a possability there might be more dammage than you thought,or that is visable this can really turn ugly for you or any club members nearby,when that thing is spinning at 10,000 rpm.

trying to save 2$ for a prop,that can have any problems, its really not worth it .