Microlighters

I need to replace my prop due to insuficient pitch. I currently have a p de necker prop which looks extremely good but is like judo. It doesnt work

I have to replace but I would like some info regarding the diffs between wood or warp before I buy.

The culprit is a Bush Baby with a 2.3 vw motor.

Any advice is welcome accept Boets about a boat anchor. Hallo Boet

Warp, you can atleast play a bit with the pitch and it's an excelent prop.

Unfortunately one cannot fit any composite blade to a direct drive VW. Its got to do with engine harmonics. If it is through a re-drive, fine.

I have a reduction drive and I tend to agree with KFA regarding the ability to play around with the pitch on the warpdrive.

Thanx

I have a similar decision to make. Seems like it is personal preference. Some pilots swear by P-Prop and others by composite.

Info gathered so far (not my personal opinion):

P-Prop - Good
P-Prop is cheaper and easier to repair.
Works well if you get the right pitch.

P- Prop Bad
If it is not what you wanted, you have to order a new one
Shape of the wood may change due to moisture etc. and cause excess vibration.
Heavy and puts strain on the gearbox and engine to get it going.

Composite - Good
Ground adjustable pitch.
Very little vibration
Not as heavy

Composite - Bad
Expensive
Can not be repaired easily

What does the prop experts say?

P Prop:
Good price
Local product
Good back-up
NOTE: You can always trust a tree.

Warp
Expensive
Not as effective as th P-Prop
NOTE: Always the risk of throwing a blade.

2c

Boet wrote: Not as effective as th P-Prop

Please explain WHY
I really need to understand props better.

yes alas all that has been said is true, except I haven't yet seen a warp throw a blade.

My opinion
Wood
-beautiful
-you live with what you get wrt pitch etc
-not ideal in very stoney environments, especially in the pusher config
-rougher than a 3 blader
-most efficient config
-doesn't like moisture

Warp
-Extremely hardy
-easy to replace a single blade it damaged, instead of the whole prop
-infinitely ground adjustable to get the perfect pitch
-much tougher than the other 'composites'
-smoother, albeit very slightly less efficient than a two blader.

I love my warp drive, but I have also had composites and solid wood

I've got both....

I use the P-Prop in the summer & the Warp in the winter!

If you set the tracking right on the P-Prop it is really not that bad. My P-Prop bliksemed a stone on the leading edge... We fixed it in a jiffy and flew out with it.
don't think I would have done the same with the Warp though!

Brian

I am in the process of replacing the Brent Thomson wooden prop on my Bushbaby with a Warp adjustable prop. I have got a Jabiru 2200 85HP engine installed.

I am expecting the prop to arrive within the next 2 weeks, and after installation, tuning and testing I will be able to give you first hand experienced advice.

I am changing to Warp because I experienced exactly the same problem as you are: not the right pitch for the job, and not enough dough to keep on experimenting with different wooden props.

I would like to hear others commenting on the statement that a composite prop does not work with a direct drive engine because of harmonics????

I based my decision to go for warp on the results from a performance data sheet found on
http://www.kitfox.eu/technical/proptest.html,
recommended by KFA



Regards

Chris

Hi Chris, keep us posted. The Canary is complete(85hp Jabi). We are busy with final fiddling. Will fly soon. We are plying with a thee blade warp, but i think we will settle for a two blade P prop or a two blade warp when we have all the data collected. New cowls also completed but we will only make the final one after we have done all the testing.

Interesting reading.

http://www.auf.asn.au/groundschool/propeller.html

It looks like an adjustable prop is the thing if you are not sure what you want or want to change the pitch depending on the conditions of your flight.

Hi there Chris

I was fortunate to borrow a warp drive from a mate and the results are awesome. My revs used to peak at 5000 and is down to 4100. Cruise used to be at 3900 rpm to maintain 80 mph. I am now cruising 87 mph using 3500 rpm but was advised to go even more course on the pitch.

I was reading your posts under "projects" last night and therefore understand your frustrations as well.

I will post all results as I go along and I am waiting in anticipation to hear from you concerning your specs when you receive your new prop.

Regards
Brian

You only mention cruise - what is climb performance like or have you paid the price there?.

Some experience with 582 Bushbaby:. Originally delivered with Hennie Malan prop - not bad but had some vibes. replaced it with P Prop that worked very well until nose over into sand. Flew back from kalahari on Hennie Malan prop. Ordered new PProp to same spec but had problems - think it actually was overpitched. Fitted Warp drive and now very happy. Not quite the performance of the good PProp (and woema is all important in 582 BB) but you set it up exactly and it can chop rocks.... Regarding vibes - the Ivoprops had an issue because of the way the blades were fastened (clamped between 2 plates) - I think you may still find some gen on the Ivoprop website. They said avoid 3x reductions with 3 bladed prop. Trust Boet with a BB - he is the BB oracle...