I would appreciate some telling me the most common scale ratios used in building scale aircraft. 1/4, 40%, etc.
If I was to build a plane using 1 inch for 1 foot, would that by 1/12 scale and, if so, do people use that scale, normally?

Thanks for any help.

Roger, naturally, the answer(s) depend on the size of the original aircraft. Seems like most WWII fighter models are in the 1/6 and 1/5 scale range. WWI fighters are also to be found in 1/6 and 1/5 but 1/4 scale is also popular. Civilian models like the cub are also commonly built in 1/4 scale with an occasionally ambitious project at 1/3 scale. Only aerobatic planes ever seem to be built in "percents."

It really boils down to wingspan. It seems like most scale modelers like to have to keep their models within a practical range. About 60" seems to be the minimum for most (gas vs. electric) RC modellers (with occasional exceptions for multi-wing aircraft) and most of us consider a model with over, say, a 84" wingspan to be pretty big.

Generally speaking the only "scale" models done at 1/12 scale are (very) sport-scale WWII fighters done for scale combat contests or larger multi-engine scale projects.

What are you thinking of building? If this is your first scale project, I'd encourage you to think big(ger). I built a Fokker EIII at 1/6 scale (about 62") and while it looked enormous on my smallish workbench at home, once I got it out to the field it looked really small. BTW, you might also want to thing about what scale assessories are available and in what scales for the plane you're considering.

Good luck!

What a terrific answer.

That little tid-bit can be the most aggravating of all the problems that arise in building scale models.

Try fabbing up an ignition switch and key at 33% sometime . . .

I wanted a _large_ B-17G. I started the project by trying to whip up a Norden sight. Whut APITA !!!

Thanks for your reply. I have several hours in a 600 hp Grumman Agcat, which is a radial bi-wing crop duster, and I have always wanted to build one for myself. One of my homebuilt planes has a 43 inch wing span and after studying it for some time I decided that would probably be buildable for me. This Agcat has a 42' 2 3/4" wing span and at "one inch=one foot" would give me the above described wing size. I want it to be electric, so, I do not want it to be too heavy. I think I can bring this size plane in at about 2lb's and would be just about right for electric using brushless. I have spent the entire summer building, flying and experimenting with making my own planes and scale parts. I have the full scale plane here to build from along with precise three view drawings from the maintenance manuals.

That is why I was wondering about common scale sizes, to see if a few things might be obtained ready made, i.e. wheels, radial engines, struts, etc. Looks as tho that would not be the case.

My avatar is a fun drawing of the 600 Agcat.

I would be open to any suggestions you might send my way.

Thanks again[8D]

The real question is how OBSESSIVELY do you want to get into scale detailing? Are you planning to replicate the panel lines and rivets, AG spray system, rib stitching (if the plane has it)? Will you have a scale airfoil, scale dihedral, scale flying surface movement and hinging? Will you have hidden servo connections, functioning scale undercarriage? Will you be doping silk to replicate the finish of the original? Wil you be using paint chips from the original to replicate the color scheme? That is, just how obsessed are you thinking of becoming? It's possible to go WAAAAAAAAAAAAY off the deep end or alternately, you could just have fun building a nice flying model that sorta looks like a favorite plane, i.e. right number of wings, similar paint job and markings, and snoopy (or a troll) in the cockpit.

Now the reason I ask is simple: scale detail adds weight. A bigger model carries more of this weight. Therefore, in theory, the larger the model the more potential for absolutely obsessive scale detailing. At 2lbs, you're not going to be able to do much detailing. At 43" you won't be able to see a lot of detailing. But if you're commited to electric, I suppose 1:12 wouldn't be a bad size.

BTW, if I remember correctly a crop duster of some sort (I'm not really up on my Ag types) recently won or placed highly in the National Scale Championships. It DID have a working crop-spray system. Can someone post a photo?

BTW, the Agcat looks like a cool scale project! Lots of funky detail!

David Hayes built a Thrush ( I think that's the name of the plane).

That is the correct name for the plane.

Thanks, abufletcher. It's a combination of the above and not something I plan to build in any hurry. I am retired with a disability and can do nothing else now, so I have the time. As I said, I have always wanted a model of the plane and since I am now in RC I decided to do it that way. When I mentioned "This Agcat" it was to indicate there are different models of this plane. It was first built not long after WWII and has been one of the safest crop dusters ever built, and was first built by the Grumman Corp. I can personally attest to the safe part. I have seen what dead men have seen.[8D] Not many have been in a plane, drop 200 ft, hit the ground nose first and walk away with one scratch on his arm from his watch band.

I have a foam wire cutter which I built. I have considered using mostly foam so I can fly it and easily make replacement parts. And, I have considered making it all wood. And, a combination of the two. The full scale plane has mostly metal skin. I am from a family of designers and inventors and have come up with ideas of my own on making some of the scale stuff.

Yes, I want most of the skin to look correct. The fuselage sides are corrugated metal panels. (I have been studying some ideas for that) Only the tail surface and the under side of the wings are fabric. I do not intend to try to copy any surface texture of the fabric. There are hobby shop wheels that look plenty close enough if I come up with the right scale to build. I will make the spartan instrument panel, the spray controls, the pump that hangs under the engine, foot steps, etc. I know how to carve parts from wax, cast them in plaster, melt the wax out and fill with resin. I can then make minor adjustments in detail and color.

I know it will not be easy. It's just something I have a life long desire to do. I am sure I will be posting lots of questions and reading lots of existing post in the future.

Again, thanks. [8D]

I forgot to mention that I have a full scale Agcat available in the family to get what ever measurements and shapes from.

Sounds like you have a plan.. good luck to you and please keep us posted with your progres. FYI instead of using the lost wax technique you might make your parts from abs and then cast them in casting resin. It may save some time..

Thanks BobH. I am not sure what you mean about making the parts from abs and casting in resin.

I am just now getting the plans laid out in actual size using a scanner and algebra to enlarge the manual drawings correctly. I am working on printing the very large drawing in sections. Will save a lot measurement conversions.

I mean that you can make parts from abs plastic.. which is easy to work with. After you make one part.. you can make multiple parts from the original.. if needed. For a plane that might require multiple parts.. like nozzles. it would be useful....

Now I get you. I will think about that. Thanks!

Agcat, with the level of detailing you seem to be interested in (and the sort of weight that implies), I would strongly recommend that you build at the larger 1/6 scale and that you build using traditional all-wood techniques. Just out of curiousity, what sort of RC modeling experience do you have? What sort of construction techiques have you used in the past?

I built my first ever scale RC model about 6 months ago and it was a real learning experience. It was entirely scratch-built from technical drawings. Prior to this I had built a lot of those Guillow's kits as a kid but never an RC model. All in all, I think it came out pretty well but I'll definitely do a lot of things differently next time around. Mine had a 62" wingspan and with all the scale detailing came out a tad heavy at about 8lbs. Here are some photos:

http://www.rcuniverse.com/forum/m_19..._1/key_/tm.htm

Wow! Now that looks great! I have built models since I was a kid. Built a 3ft wing span covered balsa ME-109 at eleven. That was in 1965. I have built other things. For instance, I built a TriCorder from Star Trek Next Generation with all the lights blinking, etc. Made it from a block of wood and when finished it looked just like the one on the show. It was for my son. I made the panels with graphics and labels for the buttons. It was fun. I am from a family of designers and inventors, my dad and brother have several patents. I worked with them building some of the patterns, jigs, etc. myself. Saying that only to let you know that I have some ability to create some of the scale stuff myself.

I have been building and flying my own planes all this year. I haven't gotten perfection in mind yet on the current one shown below. I am using it to practice making what ever I need. I built this one (the red plane, not the glider) from my on design, complete from scratch and it flies great. It's has a 55inch wing span and weighs 27oz. I use a brushless electric motor with lots of power to spare.

I understand completely what you are saying, I just did not want a plane so big that I could not display in my home office easily. I may need to start with the small one with less detail first and then proceed with the larger one. I do appreciate your input.

Here is a photo of an Agcat 600 that has been converted to turbine by us. I don't think there is really a lot of scale stuff that has to be heavy to build this plane. Most will be the radial engine.