|Oct 04, 2003, 10:21 PM|
This thread is for anything relating to making a propellor.
Blades, spars, hubs, materials, forming technique, etc...
Anything you can think of about making your own props
with pictures or even just a tiny tip on a well known technique.
I'll start off with a bunch of links.
Inside Story Rapid prototyping in the microwave by Peter Frostick.
Inside Story reshaping plastic props by Ralph Bradley
Inside Story Carbon Fiber Props by Gordon Johnson
Double Whammy Pennyplane article describes forming a balsa propellor on a cylinder and making a pitch guage.
Direct Link to PDF
Another Pennyplane article describes forming a balsa propellor on a cylinder and making a pitch guage by the Thermal Thumbers of Atlanta.
Blue Foam Prop Block Frame Construction
There more info on making built up props also
and plans for a pitch guage.
Hobby Shopper EZB Construction Guide by Larry Coslick & Steve Gardner from Indoor News and Views
Or follow this link you will be outside of the frameset.
Pages 4 and 5 of Describe prop and prop block construction.
The Idiot's Guide to Prop Carving v2.02 From David Dodge
Carving An X Block Propellor
And XBlock Prop Calculators
Carving a balsa prop
Nice info on determining size and pitch from model size.
By Free Flight Online
Del's Prop Calc Page
Explanation of math behind pitch with a calculator.
Secrets of Indoor Props by Carl Goldberg
From the pages of the January 1938 issue of Model Airplane News
Provided By Kenny's Old Time Model Airplane Magazine
For advanced math on the subject of propellor airfoils Dr. Martin Hepperle has a wealth of info on model aircraft aerodynamics.
Follow the propellors link
A page describing the laminated fan method.
Here is a page by Koichi Tanaka describing how to carve a propellor. Koichi has a lot of other technical information on his website that is very useful for building Indoor and Micro models including a flight calculator plus schematics for making an Infra Red RX and TX as well as lots of other useful info. Koichi's site is in Japanese so you might have to use altavista's babelfish translator to read it.
Here is a technique to form your own plastic props either in a vaccum former or with a negative mold and a toaster oven.
Epilot's carbon fiber prop making thread
Greg's (gbarc) Aluminum prop construction
|Oct 04, 2003, 11:38 PM|
Wow that is a great set of resources. This needs to be connected to the hints and tips thread and the index.
|Oct 05, 2003, 02:18 PM|
Thanks you guys.
I should mention that I have tried all the techniques listed except for the laminated fan(well I have laminated 2 or 3 strips) and Gordons Cf method(I will one day get to trying this one I know it works very well and may very well produce the best props of all the techniques) . All the techniques work.
Not mentioned in any of the links is how to make the yogurt pot prop so it would be nice if someone would write it up and take some pictures.
I have made some styrofoam cup props which are lighter weight than yogurt pot props(at least on this side of the pond) and they hold up better than balsa when you are test flying a new model.
Balsa blades can be strenghtened with a bit of tissue covering.
Lately I have been carving props using Keveney's prop block calculator. The block that offsets the tips to the rear(backside) makes some pretty props.
For making quick props I use Del's block calculator or sometimes I'll use a glass cylinder(a tall shot glass works good for tiny props for 6" and less planes) and wrap with thread and throw in the microwave for about 90 seconds like in the "Rapid Prototyping" link. Make sure you put a coffee mug in there with some water in it so you don't burn up the inside of your microwave. My microwave is so small I only add about a 4oz of water (TLAR) and this seems to do fine. You might have to add more water for more powerful microwaves.
I have one question has anyone seen a built up prop on an electric powered plane?
|Nov 12, 2003, 11:56 AM|
Here is another
This link will take you outside the frameset.
So If you want to view the whole site use this one
And go to articles then scroll down.
There are a few articles I think on Ken Hornes website about props and I have a few articles in PDF format from old magazines I just have to gather them up and see if it is ok to post.
|Nov 12, 2003, 07:52 PM|
I forgot about that one.
I was looking at it the other day too.
I'll dig it up later if no one beats me to it.
I received some polymicro in the mail today and I'm off to try a built up propellor. I have been on here too long. I keep going over to the building board and working in spurts. So far today I have taken apart a pager motor tried to put it back together and started reparing my rubber winder and made a zillion posts and read a zillion more on the Ezone.
|Nov 13, 2003, 01:42 AM|
The marcee.org prop page is about helical pitch prop carving.
It is from an old magazine. It has some nice drawings of the process and formulas. I have not had a chance to read it thouroghly yet but looks to be pretty good information.
Thanks for the link Gary.
|Nov 13, 2003, 04:59 AM|
One thing puzzles me: Why do almost all descriptions involve carving a balsa block? Why not hot wire cut the former from blue foam? Just make two cutting templates with prop curvature and all? Did I miss something? (probably did) But it would be nice and easy, wouldn't it?
|Nov 14, 2003, 12:54 AM|
The problem with foam forming blocks is hat they don't stand up
to baking balsa prop blades in the oven!
But hot-wireing prop baldes out of a foam block, now there's
an idea. Has anyone tried that?
|Nov 14, 2003, 06:44 PM|
I went digging for my EZB prop form to take a photo but could not find it. It is made from foam with a cardboard side and bottom.
I think there is a photo somewhere. but it wastaken with an old pencam. That is where I got into the dusty boxes the other night.
I'll have to make another one.