The ugly duckling Grumman J2F-6

# 1 10-01-2003 , 10:41 PM

Subscriber
Join Date: Aug 2002

Posts: 1,135

First flight 25. April 1933, with the XJF-1.
First delivery of the JF-1 to the service in US, May 1933.

Produced with these varieties;
XJF-1
JF-1:
JF-2:
JF-3:
J2F-1:
J2F-2:
J2F-2A:
J2F-3:
J2F-4:
J2F-5:
J2F-6 (Columbia):

Some aircraft were designated OA-12 in 1948, for rescue service in Alaska.

Technical Data Grumman J2F-6 Duck:

Wing Span: 39 ft 0 in (11.9 m)

Length: 34 ft 0 in (10.4 m)

Height: 14 ft 6 in (4.4 m)

Wing Area: 409 sq ft (38 sq m)

Weights Empty:
5,480 lbs (2,485 kg)

Maximum T/O:
7,325 lbs (3,322 kg)

Maximum Speed:
190 mph (305 kph)

Cruising Speed:
155 mph (249 km/hr)

Service Ceiling:
25,750 ft (7,848 m)

Normal Range:
875 miles (2,408 km)

Powerplant: One Wright 1820-54 Cyclone rated @ 1,050 hp (783.3 kw)

Armament: One .30 caliber Browning Machine Gun
Two 325lbs (147,4kg) bombs/depth charges

The pic below shows the version I'm going to model. It is not the latest version, but I like it due to its "nostalgic" nose, around the star engine.

Last edited by undseth; 10-01-2003 at 10:44 PM.

Quote

# 2 10-01-2003 , 11:42 PM

Subscriber
Join Date: Dec 2002

Location: Idaho USA!!!

Posts: 492

Very interesting. Looking forward to seeing your progress.

https://www.darrylworley.com/

https://www.defendamerica.mil/nmam.html

Quote

# 3 10-01-2003 , 11:51 PM

Subscriber
Join Date: Aug 2002

Posts: 1,135

Just getting started with some sketching

Got hand on two drawings. They look ok, so I hope they won't give me much trouble.

I'm thinking of making a nurbs-patch model, as I cannot see how Im supposed to make the model out of primitives alone. I'll try to make some nurbs-surfaces, and attatch them. I hope it works. I'll have to wait to trim the nurbs-surface, else the attatch surface tool will not work.

Look forward to make some decent bump maps, so I don't have to model the bulky metal skin on the wings.

Btw, I read that this was one of the first aircraft that was skinned with metal, and not canvas.

Quote

# 4 11-01-2003 , 03:24 AM

Registered User
Join Date: Jul 2002

Location: long island n.y

Posts: 484

um okay im not a big fan. of non organic stuff. but.. the name alone has drawn me. will be keeping my eye on this. good stuff seth oh beed.

Raul

https://keytogramcypark.deviantart.com/

Quote

# 5 11-01-2003 , 03:31 AM

Subscriber
Join Date: Oct 2002

Location: USA

Posts: 1,172

Looks like you plan on putting a lot of work into this project. Can't w8 for an upd8 m8.

www.Darkware3D.com

Quote

# 6 11-01-2003 , 03:51 AM

Subscriber
Join Date: Aug 2002

Posts: 1,135

A little update on the "duck" NURBS

I toyed around with the surface tools and figured out how I could build the fuselage. Here's the plan.

The wings are pretty straight forward. No problem.

The tricky part is to decide on how the cross sections should look like. I do not have any blue prints that deals or help me with the issue of cross sections. I want to keep the cross-sections at a minimum (easier to tweak, and a cleaner result, unless you want to spend time tweaking the small cvs to give the hull a nice continuity).

I have found a way to model the fuselage. I will create curves as cross sections and use a mix of the surface tools.

-Birail tool, several profiles and two rails.
-Fillet blend
-Attatch surface

I guess the trick is to keep the various surface-pathces "attatchable", so that I can weld them together, making a whole and beautiful fuselage.

The big floater will be treated as a seperate object or as a set of objects. No need to attatch it to the main fuselage.

Earlier (some time ago) I used to get annoyed at failing to attatch nurbs surfaces together. But now I have learned to discern the open surfaces from the closed, from the periodic.

The attatch tool will only work when your nurbs surfaces are un-trimmed. So the small trimming will be done later.

Future trim actions;
-trimming for placement of the cockpit
-trimming small holes and such
-possible trimming to shape the tail-rudder (balance-rudder)

At the end the nurbs-surfaces will be converted to polys for easy texturing.

Quote

# 7 11-01-2003 , 06:33 AM

Subscriber
Join Date: Jun 2002

Location: Texas

Posts: 374

Very interesting undseth. Look forward to see this progressing and hear how you are diung things. I'm trying to get a grip on patch modelling myself right now. Hopefully i'll learn a few things from this model.

Quote

# 8 11-01-2003 , 09:21 PM

Subscriber
Join Date: Aug 2002

Posts: 1,135

Tiny update

Well, not much but I'll go work on the cross sections tonight.
This is the status quo.

Last edited by undseth; 11-01-2003 at 09:23 PM.

Quote

# 9 11-01-2003 , 09:59 PM

Subscriber
Join Date: Aug 2002

Posts: 1,135

Trying to make that beautiful fuselage

This is not the "skinning process". Only some easy lofting to see how the surface shapes itself after the few curves it is based on.

I have a good feeling about this, although I do not know for sure that my ideas will work.

Quote

# 10 11-01-2003 , 10:11 PM

Subscriber
Join Date: Oct 2002

Location: USA

Posts: 1,172

The second to last image you posted seems a little dark. I can see what's there, but I have to look closely to see it. Is it just my monitor?

www.Darkware3D.com

Quote

# 11 11-01-2003 , 10:40 PM

Subscriber
Join Date: Dec 2002

Location: Germany/Canada

Posts: 545

Hey undseth - really like how you're going through all the thought processes in planning - you can learn a lot by following along - i've been going through the same process modelling a mclaren with NURBS and trying find out which tools work and when is a good time to trim etc.

I'm taking a break to do the december competition though and something organic. old machines like the ugly duckling here are like beasts with muscles and teeth - looking forward to seeing how it develops

Check out the subsurfacescattering on my tongue...

<a href="https://www.reitzmachine.com">www.reitzmachine.com</a>

Quote

# 12 11-01-2003 , 10:50 PM

Subscriber
Join Date: Aug 2002

Posts: 1,135

Not much here.

Darkware: sorry, the jpg compression from photoshop weren't good.

Ereitz: Good to hear there are others that work with nurbs too. Maybe you can help me with the birail tools.

The pic below shows more clearly how I am supposed to skin the bird. The curves below are just a duplicate for testing, so I'll post the start here and you will all see me complete or lick the asphalt.

Quote

# 13 12-01-2003 , 02:26 AM

Subscriber
Join Date: Aug 2002

Posts: 1,135

Birail tools are wierd

I learned much about nurbs today, but the mystery of the birail tool still eludes me.

I have trouble making surfaces that are smooth. Even with smooth curves (rails/profiles) the surface still gets bumpy.

So at the end of the day I have simply lofted a few curves, and... more to come tomorrow.

Quote

# 14 12-01-2003 , 02:32 AM

Registered User
Join Date: May 2002

Location: Niagara Falls, Canada

Posts: 5,310

heheh yeah i hate birail, I can only seem to get biral 2 to work. Great start bud=)

I am enough of an artist to draw freely upon my imagination, knowledge is limited, imagination encircles the world. (Albert Einstein)

https://www.artstation.com/kurtb

Quote

# 15 12-01-2003 , 04:52 AM

Subscriber
Join Date: Aug 2002

Posts: 1,135

Thanks, I had to get up from bed to figure out the surface-rebuild-tool. It wasnt much helpful for my problem, but it can be handy later on.

Im now settling for lofting the fuselage fore and aft. The tricky middle part is done with the boundry tool. I found out that; by rebuilding the curves, the boundry surface turned out a little prettier. Way from perfect, but it is now tweakable.

The following pic shows the surface to be tweaked. And with newly gained experience, I will be able to attatch the parts together. user added image

edit:
I cheated with the 10 span curve. It was supposed to have a hard edge, but I removed it and simply moved the round edge downwards, so it won't be seen when the floater is finished.
edit2:
Correction; the 10 span is actually a 13 span...

Last edited by undseth; 12-01-2003 at 04:57 AM.

Quote