APC or Wooden Props?

[Adrian Smith 1]

I have always used APC props on my IC engines but I am now using some of the bigger glow engines such OS 120 AX and the OS BGX - 1 and wondered what the pros and cons are in changing to wooden props for aerobatic use given that wooden ones seem cheaper at some outlets.

[Martin Harris - Moderator]

I've found that the Graupner G-Sonic range give good results at substantially lower prices than the (very similar) APC props.

[Adrian Smith 1]

Interesting Martin thanks. Will have a look at those and test one or two out. I must admit I have my doubts about wooden props but I thought it would be interesting to hear what people thought of them.

[Olly Giles]

I think the reason why people use wooden props on larger engines is that they are lighter so the engine gains revs faster. (somebody correct me if i have been told wrong) Useful for 3D flying but thats about it. Id stick to what works best for you, although there is no harm in experimenting.

Edited By Olly Giles on 23/07/2011 10:23:24

[Adrian Smith 1]

Mmmmm... never thought of that Olly.

 

Unless there is good reason(other that cost) I'll probably stay with APC props on that basis. At some point I may test a wooden prop out but that sounds like a winter project.

 

 

[Former Member]

[This posting has been removed]

[Martin Harris - Moderator]

I've found lightweight wooden props prone to being thrown from 4 strokes - I suspect due to the lower flywheel effect making them decellerate faster if pinking occurs - which seems to happen more rapidly when over-leaning - again due to the lack of inertia...

 

Or I could be talking cobblers!

[Adrian Smith 1]

Sounds like very intelligent cobblers to me Martin! The ease with which they might break is a concern for me i must say.

[Stefan Hafner]

I'm using wooden props on my big aerobat, 35cc pertol, and they work great. not had any problems with them breaking during normal running. As martin says the flywheel effect is lower as they're lighter, but on bigger engines i don't think this is as much of a problem. And the JustENgines ones are much cheaper than using APCs

[Martin Harris - Moderator]

Especially if they use magneto flywheels!

[Stefan Hafner]

I think the flywheel probably helps, yes. The only difference i found was that it didn't start very well by hand with wooden props, but i use a starter anyway, i like my fingers attached

[Adrian Smith 1]

Ok thanks guys for the info. I think it has encouraged me to give them a try and do a bit of experimenting.

[Alan Cantwell]

what size prop are you after? i am clearing out several new/slightly used APC ones at bargain prices, once these things get over 11", dont know why, but the price goes MENTAL !!

[Adrian Smith 1]

Well Alan I am looking for 20 x10 or 20 x 8 ideally if thats of any use. You can private message me if you like with prices. Also I have PayPal account if that's any help. As you say above 11" and the price rockets exponentially.

[Alan Cantwell]

dont think i have any that big, but will have a look

[BB]

I use wooden Turnigy's 17 x 8 (incl 10 pec duty & carraige) from HK they work out at £4:30 (ea). I find them durable. I use 79 grm weight. You loose some RPM but the torque is almost the same as the 85 or 92 grm versions.

 

I guess it largley depends on the airframe your flying aswell as the type of flying you are trying to achieve with said airframe.

 

I have hit the dirt with my wooden props and with any prop damage to it is dependant on how hard the strike was.  I grounded yesturday at above tickover speed, the prop stopped dead.  But was ok, to my surprise.  At £4:30 ea I don't mind if they break. It has less impact on the engine.

 

BB

 

Edited By Basildon Biggles on 26/07/2011 19:49:49

[Malcolm Fisher]

I started carving my own wooden props many years ago for my control line models when it was a case of buying a new prop or another half pint of diesel fuel from my meagre spending money.

Largest I've made was around the fourteen inch diameter size and I've never had one break except when misjudging height and hitting the ground with the engine at full blast - no throttle on the engines I used then.

I believe that many large engine operators use wooden props and they were used on full size aircraft in the early days of flight.

Malcolm

[Stefan Hafner]

Thats a good point actually there BB, with expensive engines its better to break the prop than the engine

[BB]

My thoughts exactly Stefan. I would rather break a prop than an engine carrying low to mid torque in the RPM range on a heavy unexpected landing etc...

I was once told that you couldn't 3D with a wooden prop - rubbish. You can.

The props I use now are regulary sold in the UK for between 8.99 - 13.99. I buy x10 at a time from HK. I've yet to exhaust my current supply. I have had x2 ground strikes this season so far, x5 last season. I've x13 of my current stock of wooden prop for the airframe Im currently using Wot 4 23cc Zenoah with magneto. Eg, 4 seasons at £45.00 as opposed to the £63.00p I would have spent in the uk for the x7 broken so far, in 2 seasons.

BB

Edited By Basildon Biggles on 26/07/2011 21:14:11

Edited By Basildon Biggles on 26/07/2011 21:33:03

[Alan Cantwell]

HAD A LOOK, NOTHING NEAR 20 INCH, SORRY

[Adrian Smith 1]

Thanks for looking Alan, good try. Interesting BB to hear your success with wooden props on bigger engines it certainly seems worth a try and do some experimenting. Certainly from the point of view of saving the engine it's good idea.

[Alan Cantwell]

Didnt mean to shout it though, sorry

[Ernie]

Hi Guys, I prefer wood, you can work and finish hem so that they weigh less, and have a magnificent finish. Also, balancing can be made perfect. I've never had one throw a blade, but of course, they break on the slightest impact

 

ernie

 

and they look great