Republic RC-3 Seabee

**Gil** · #1 10-19-2012, 12:14 AM

Design of the Republic RC-3 "Seabee"

The design process most usually begins with researching available information on a particular subject. This includes drawings, pictures, books and online information. This part of the design process can take more time than many might imagine. Best of all would be factory blueprints though for some reason these are rarely available [or are priced outside the means of most card model designers]. Instead the designer must rely on views drawn by aviation draftsman for modeling magazines. Such is the case for the Seabee.

Included below is a near perfect side view photograph compared with Paul Matt's side view of the RC-3. This is where photos become extremely useful in correcting source documentation.

The two images have been overlaid in Rhino and manipulated to correlate the two images as closely as possible. Note that the photographic image shows that the fuselage is slightly angled to the viewing plane by the left float showing the difference from Matt's drawing.

From inspection several factors become obvious. The line of the boat section bottom to vertical cabin is not a smooth curve as shown by Matt. Also the bottom of the Port door frame is higher than that indicated by Matt. The wheel position is approximately correct as the Matt drawing wheel splits the two in the photograph. The other differences worth noting is the deviation of the front cabin profile line - it is somewhat "blunter" than that represented by Matt. The last is the after cabin bottom edge is higher than what is shown in the photograph.

This may sound as if I am complaining about Paul Matt's drawings - absolutely not! They are some of the best sources of aviation drawings that I'm aware of.

Paul Matt drawings are my first choice if available for a particular subject. What's amazing to me is that Matt was able to get drawings as accurate as they are without using modern means. I often wonder just what this great aviation draftsman could have accomplished with modern CAD entry equipment...,

Till next,

+Gil

**Yale** · #2 10-19-2012, 12:22 PM

Cool! On the one hand, the huge variety of aircraft models available blows me away. But the Seabee was a specific model nobody else seems to have designed. I'll follow your project with great interest.
My understanding was that the Seabee was in production for 20 0r 30 years, so would expect there to be differences between early and late models. Could that account for some of the differences in your drawings? Even if so, your overlay technique seems like a clever way to design a model that represents all the Seabees.
Thanks and best of luck.

**Gil** · #3 10-20-2012, 01:02 AM

Hi Yale,

Glad you like it. You're right about the RC-3, it's a pretty rare example in the modeling world. I'm getting to really like this airplane a lot. Instead of ribs Republic indented them in the wing and tail feather surfaces. If you've ever built ribs for a full size airplane you can really form a close and bonding affection for such an idea.

After an appropriate period of messing with Rhino the following was coaxed out. The bottom "boat" and tail are separate from the top cabin area - just like the subject.

More as it comes to me...,

+Gil

**Gil** · #4 10-20-2012, 06:37 PM

Fuselage is now roughed out [Version 3 - not too bad!].

The cabin section will need to be re-lofted after engine and wing are roughed in - this will only affect the rear section leaving the forward section construction layout untouched. Also included is the "SeaBee" Logo - took awhile to get the render to "look" just right...,

+Gil

**Leif Ohlsson** · #5 10-21-2012, 12:53 AM

Very beatiful, as with all your Rhino work! - L.

**Gil** · #6 10-21-2012, 02:03 AM

Hi Leif,

Glad to see you tuned in and thanks.

The SeaBee and the Wilga PZL-104 share many similar aluminum construction techniques. I've also collected a stack of research material on that subject too.

One thing I like about the SeaBee project is that I'm not sure about construction details but decided not starting the project was worse than playing tweedle-di and tweedle-dum over it. Just have to see where it goes and how it develops.

I've putting in a bit of work here and there on a project we are both have a stake in when I find time.

Last, but not least, I finished the roughing-in the window cutouts for the SeaBee. For a lot of reasons, this is one of the more traumatic things known in getting a design right. Most source material is "plain awful", in this respect, so a lot of photo interpretation work is required to get this detail correct....,

Best regards, +Gil

**JohnM** · #7 10-21-2012, 08:47 AM

Ooooh those gorgeous curves. That makes my humble effort look like a different aircraft.

But, slow as I am, I think maybe I'll have a completed model on my windowsill long before you do Gill.

johnny.

**Leif Ohlsson** · #8 10-21-2012, 09:58 AM

Always nice to see your beautiful rendering of the Druine Turbulent!

- L.

**Gil** · #9 10-21-2012, 01:11 PM

Quote:

Originally Posted by JohnM

Ooooh those gorgeous curves. That makes my humble effort look like a different aircraft.

But, slow as I am, I think maybe I'll have a completed model on my windowsill long before you do Gill.

johnny.

Nothing like a sure bet...,

Quote:

Originally Posted by Leif Ohlsson

Always nice to see your beautiful rendering of the Druine Turbulent!

- L.

I think it's kind of pretty, especially getting the plywood to look right...,

The subject SeaBee design is somewhat of a magical mystery tour - finding all the hidden details in both drawings and photographs.

Removing major components, like the wings, reveals structural details that prove their weight in gold. Such is that exhibited in the image below - and is why I like pictures of derelict and salvaged aircraft - restoration blogs are also gold mines of information.

The wing has been removed revealing spar connections and a rear bulkhead that angles down to the wing strut and landing gear structures. A little image detailing of the area of interest was performed in Photoshop to make this clearer. This is not on any drawing I've come across showing how important the internet is for digging out this type of buried detail...,

+Gil

**Ron0909** · #10 10-21-2012, 02:24 PM

Gil it's awesome to watch you do your thing

If anything (and it's no small thing) you always manage to get me distracted and looking in some other wonderful direction from the one I'm heading in! I *know* you've been here Republic RC-3 Seabee Amphibian
but for those who like to sniff around, it's a cool place. When you design, do you create with unfolding in mind right from the beginning? or is it something that comes into play after an initial shape has been determined?