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Archive for February, 2010
Posted by ODUsurfer | Feb 24, 2010 @ 07:01 PM | 2,533 Views
So I see lots of questions about foam, particularly confusion and conjecture about the different types of foam out there. I am no expert, but as an engineer and scientist, I decided to do my homework on the topic, and post up my findings to maybe help people understand the differences.

Most everything I will post up is from fact-based websites like wikipedia and the like. I'll try and cite sources where I can.

The Basics
In order to make foam, you start with a plastic polymer of some sort, and "expand it". (The "E" at the beginning of "EPO" and "EPP" always stands for "Expanded") You start off with a dense plastic resin material, mix it with a catalyst and it fills with millions of tiny gas bubbles while expanding to several hundreds of times its original size. If you think about how a popcorn kernel expands out into popcorn when heated, you're not far from the mark.

Now the real key between the different types of foam is the base polymer expanded.



More to come.
Posted by ODUsurfer | Feb 23, 2010 @ 11:19 PM | 3,208 Views
So the question is, what's the largest prop you can put on a 24" wing without having major torque roll problems?

I have a Mini Speedwing that I used a Feigao 1208436L on, and quite honestly I found it very underpowered. Doesn't vertical, doesn't go super fast, and I find myself at 100% throttle almost the entire time.

I have an extra 1700 KV 2712-17 outrunner from another plane lying around, and am going to throw it on there... Only thing is the RPMs are obviously much less, and I'll need to get the biggest prop on there as I can. -Just worried about torque roll. I have a 6X4 prop on it right now, but I think I'll get one a bit smaller before trying to fly it. Will update.
Posted by ODUsurfer | Feb 11, 2010 @ 09:29 PM | 2,690 Views

What a great plane! But let me tell you, it took some work to get this thing flying right.

Intro
I spent quite a bit of time with faster foamies, like GWS warbirds, and the GWS Formosa. But quite honestly I missed having a lazy, slow flying biplane. But I definitely wanted acrobatic capability. So that's how I came to the decision of wanting a light 3D-ish acrobatic bi-plane.

That said, I narrowed my search down to a couple different planes: GWS Tiger Moth 400 (modified with 4 moving ailerons), the Ultrafly Furious, and the Great Planes "RC Universe" Flat Out Biplane. Ultimately the Tiger Moth was eliminated because I wanted something I could use my (6) 2-cell 1000 mA batteries with, and the RC Universe Flatout was eliminated because of horror stories about how fragile it was, and the strong recommendation of the Furious from a guy I trust from my local hobby store. Easy enough!

It should be known that the Ultrafly Furious has a sister plane, the Ultrafly Outrage. They have minor design differences, and supposedly the Furious has slightly larger control surfaces. But from what I understand from those that have flown both, they are basically the same plane, only the Furious is red, and the Outrage is Yellow.

The Furious is marketted as an "Advanced Parkflyer" and a "Beginner 3D plane", and it fits that perfectly. If you are looking to make the transition into 3D with an easy flying plane, this one might do it for you.

Building
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