Carved balsa eflite prop

[Ratz (Bruce)]

Looking for some additional flexibility in my prop choices for a E-flite Park 180 outrunner, I made an attempt to carve a 6 inch diameter by 4 inch pitch prop pattern after a commercial plastic prop of appropriate dimensions. Not.my first attempt at prop carving but this small was a first. I used a mathematical calculated prop blank from other references and ended up with something that may just work. I will have to give it  a number of coats of polyurethane to firm it up. So we will see.

[Rekitus]

looking for additional ...

"Looking for some additional flexibility in my prop choices..."

OK. all by itself, I paused.

what are you wanting to flex? 
you didn't say looking for a spare prop.

I can tell you balsa props are up to the task
of pulling an 049 control line plane if you add a hard wood hub...
and they are VERY fragile.  never got two flights from one prop.

[Ratz (Bruce)]

Flexibility in the abilities to make my own props in various diameters and pitches using materials at hand. Carved props will never be as effective as the plastic ones but I am not wanting to buy a pile of plastic props just to experiment with P/D ratios. I have plenty of time to carve...

Bruce

[Starduster]

I have plenty of time to carve...

Bruce

One word: "wow" - Though I admire you for this effort, for me, this would definitely come under the "What's your time worth?" category. You will, as Rekitus said, have to replace the prop after each flight. At 2200Kv. I'd be surprised if you even get one flight per prop. I certainly would not want to be near you when you power it up.

For a couple bucks each, a $20.00 investment would pretty much fill your toolbox with props.

BTW - Carving props is one of my favorite modeling activities, but I'd never carve a balsa prop for a power model.

[Ratz (Bruce)]

Well initially the plan was to carve it from a fan fold blank of 1/64th ply... but I had to go through this stage to verify my carving process. Now that I have my dimensions and carving worked out, I will try one out with some other material. We will see, your mileage may vary...

Bruce

P.S. or I will give up...

[Starduster]

Well initially the plan was to carve it from a fan fold blank of 1/64th ply...

How about Basswood? Strong enough and easy enough to carve.

[Ratz (Bruce)]

Yes basswood, I have some have not ruled it out eather. Might just try that too.

[Rekitus]

I am far more interested in the reasons to have the different props.

most times trying different diameters and pitch angles are to get
some sort of improvement in performance. 
so while I have read that matching engine rpm and pitch is possible,
somehow, to meet the best L/D ratio for the best efficiency.

For rubber power, I've not gotten past the OMG it flies!!! stage.

I long time back I recall reading that plywood is not a good idea for props.
the explanation was uncertainty in the manufacturer glue and little
pieces of crossgrain flying out.
I'd hunt clear grain spruce were I making props for electric motors or engines
as big or larger than the peewee 020's

I guess I should explain my balsa props broke in landing. 
we hand launched for fear of a rock or pebble strike.
the balsa I used was heavy and looked like tiger fur...
overall a cox 049 is past the inherent ability of balsa.

carving props can be entertaining.
it is easy to get a serviceable prop, 
I do wonder how to carve a truly nice prop.
that is a big part of why I am reading this thread.

victor

[Ratz (Bruce)]

Ok I will explain myself. In my intrest in developing a propeller process of "making" my own props is to standardize a method to obtain props for a power plant system that I have and will use with a number of airplane projects. The image below is such a system. I am building a P-30 that's being converted into RC found in another thread. But... the Hornet P-30 is just a test bed for this system.
Yes I could just buy a plastic prop for the job, but l want to be able to make the props in need for this system and various projects that it will go into. I now can do the math for any prop block pitch and diameter I choose. Then for this system make a suitable prop for any said application.  Perhaps I am going down a rabbit trail but perhaps not. Once this test bed, power system and airplane is mapped out I will know for sure what power prop system I have. I will be able to design any airplane I like to use this system with. Perhaps a bit ambitious but I am on a quest to know what I have and then I will design some planes for it. I like to do airplane design and have done a number of successful designs before.

My mileage is going to vary...

Bruce

[greggles47]

Bruce,
Some time ago a mate of mine built a 2.5cc size speed model (Assymetric) with a balsa wing which he coated in light weight carbon cloth. This he attached with CA adhesive.
The resulting  wing was light but stiff enough to cope with speeds over 220kph.

I cannot say if this would work in your case, but could give you something to consider.

Good luck, it sounds like an interesting approach.

[Rekitus]

ok that catches my attention...
so you think to do that with a propeller?

mmmm I may try it...

[Buster11]

Balsa prop blades covered with carbon cloth have been almost universal for F1B Wakefields for maybe 20 years. Here's one type:
https://hummingbirdmodelproducts.com/preowned-models-and-tools/f1b-prop-vivchar

Here's another type, sold for drones:

https://www.aliexpress.com/item/1005003400365961.html?src=google&aff_fcid=2cace0ec3aea4d26907301aa3f5209ca-1708513404110-09113-UneMJZVf&aff_fsk=UneMJZVf&aff_platform=aaf&sk=UneMJZVf&aff_trace_key=2cace0ec3aea4d26907301aa3f5209ca-1708513404110-09113-UneMJZVf&terminal_id=8dc6fac1b70048adb9071da358e5c7e8&fSmartRedirect=y

[Ratz (Bruce)]

Good points from all, thanks. I have considered this project for a bit, carved a balsa prop that could be given a layer of glass of some sort. However, after reading the input of this forum I am moving down a lost trail when for some delays in time and price for 10 of them I elected to purchase... I caved... But I am getting much better at carving props for free flight building. I will report on flight performance when I acquire them.

It's often that I do some small projects that don't work out to some level of expectation. My completion rate is only 35%. Ratz would give me heck...

Ratz
"Dude, remember the rule we made for you?"
Me
"Ya Dave I do"
Ratz
"Well, what is it?"
Me
"Off the table, on the table."
Ratz
"Right, and right now Dude you are failing"

He would be laughing at me about now....

Any current project that is on a table has to be completed off the table before another new project gets on a table.

"Dude, you go from project to project, not to mention the regular work that you do in a day, you never get anything completed"


Sigh.

Anyway, my mileage is always varying.

Bruce (Ratz)