Jun 23, 2010, 03:40 AM
ancora imparo
Melbourne, Australia
Joined Jul 2005
8,233 Posts
Steve, I just had a play with a crude "boat" shape and after planking it using Kwok's triangles, I selected them all (one boat section at a time) and smoothed them using the Edit, nEntities, Smooth Edges commands. That's how I would get smooth airfoil shapes which are compound curves I think. Seems to work for boat hulls too!

The example is a bit rushed and rough and you would want to use more segments on the triangles but I think you can see the idea.
John
Quote:
 Originally Posted by SteveC68 SWEET! Thanks for that one.

# Images

 Jun 23, 2010, 09:19 AM Oh Yeah! League City, Texas Joined Sep 2006 2,629 Posts I tried the triangles thing, but it doesn't give a true hull shape. Just straight lines between the bulkheads. Although tedious what I ended up doing was dividing the bottom and sides of the bulkheads into equal numbers of segments. Then using the Arc tool to draw an arc between three bulkheads at each subdivision. Then the problem becomes making the result into a surface.
Jun 23, 2010, 04:19 PM
ancora imparo
Melbourne, Australia
Joined Jul 2005
8,233 Posts
I think that IS the problem because in my limited experience of Sketchup an arbitrary surface can only be constructed from edges that are in the same plane. All the curved surfaces I have seen are made from pushing arcs, follow-me etc. I've never found away to "fill in" an area that is not flat. That's why Kwok's solution works since a triangle, by definition, is coplanar.

Be interested in the technique if someone knows it.

John
Quote:
 Originally Posted by SteveC68 Then the problem becomes making the result into a surface.
Jun 23, 2010, 08:26 PM
Registered User
Joined Mar 2007
484 Posts
Quote:
 Originally Posted by jj604 I think that IS the problem because in my limited experience of Sketchup an arbitrary surface can only be constructed from edges that are in the same plane. All the curved surfaces I have seen are made from pushing arcs, follow-me etc. I've never found away to "fill in" an area that is not flat. That's why Kwok's solution works since a triangle, by definition, is coplanar. Be interested in the technique if someone knows it. John
This is really quite easy now if you want to use a plugin. Check out forums.Sketchucation.com site for the plugins by TIG and Fredo. They have extrude edges by rails, and curviloft respectively. I use both of these a lot in drawing fuselages and wings. The curviloft one is my favorite at this time.

Jim

# Files

Jun 23, 2010, 08:54 PM
ancora imparo
Melbourne, Australia
Joined Jul 2005
8,233 Posts
Thanks, Jim.
That's what I love about these forums. Someone always knows something useful you don't that solves a problem.

Regards, John
Quote:
 Originally Posted by JimnAz This is really quite easy now if you want to use a plugin. Check out forums.Sketchucation.com site for the plugins by TIG and Fredo. They have extrude edges by rails, and curviloft respectively. I use both of these a lot in drawing fuselages and wings. The curviloft one is my favorite at this time. Jim
Jun 23, 2010, 09:02 PM
Oh Yeah!
League City, Texas
Joined Sep 2006
2,629 Posts
Yeah that one is going to need a tutorial.

Here is what I got with dividing edges and using the arc tool. Not nearly as good as a real loft, but better than straight lines drawn between points.

# Images

Jun 23, 2010, 09:28 PM
Registered User
Maryland, USA
Joined May 2004
2,641 Posts
I gave curviloft a try. Works pretty good. Just remember, the basics of subdivison is still there. And it depends on what your goal is. If for example, you want to unfold the skin, then you don't want it that complicated.

# Images

Jun 23, 2010, 10:07 PM
Oh Yeah!
League City, Texas
Joined Sep 2006
2,629 Posts
Hot dang I figured it out! Works like a champ. Thanks Jim for posting that. I had been following some lofting plugins at the site you linked to but never could get them to work.

# Images

Jun 25, 2010, 05:10 AM
Registered User
Maryland, USA
Joined May 2004
2,641 Posts
Quote:
 How do you draw a wing with a curve leading edge and a straight trailing edge, like the current European wing and stab have?
I was asked this question by someone. So I figure, I would answer it here as it could help others. And like I said before, I don't have that much experience with 3d surface modeling. So if you have a good method please post it. I gave it a shot with TIG's extrudeEdgesByRails plugin and I think it worked great. You can download all of TIG's extrude plugins in one zipped package here: http://forums.sketchucation.com/viewtopic.php?t=25362

# Images

Jun 25, 2010, 11:03 PM
Registered User
Maryland, USA
Joined May 2004
2,641 Posts
Finished it up. Sorry, but I just notice the sketchup file is not the finished one. It seems I forgot to save at the end. So the one posted, is some intermediate file without the wing tips.

# Images

Last edited by Kwok_Yu; Jun 26, 2010 at 12:59 AM.
 Jul 02, 2010, 08:48 PM Registered User Joined Jun 2004 226 Posts TIG's extrude plugins hi everone I been trying to draw curved wings for a f3b glider and some how I can not download the TIG's extrude plugins from the skup web page. I am getting a error message when I do. I regestred on the page but I can not down load any of the plugin. Does anyone have this plugin that I can use? Also how do you show the wing section, root and tip section for a curved wing? Big thanks Sorry for asking some of you off line such basic questions off line I do not wont to clog up this thred with basic questions Thanks
 Jul 02, 2010, 09:29 PM Registered User Maryland, USA Joined May 2004 2,641 Posts You should be asking the question here. That's what this thread is for. If you have the question, others will too. And it's easier to answer it once, instead of multiple times. You are not clogging up the thread, if it is on topic. Download the plugin here: (deleted link, plugin is posted 2 posts below) What do you mean "show"? You just draw the curves. I even provide the sketchup file above, to show how to draw the curves. Here is a quick video on how to use the plugin: http://www.mediafire.com/file/mzunj000qzm/TIG's extrude edges by rails plugin.wmv Doing to tip is hard. I don't have a good method. You will have to figure it out later for yourself, after you learn the basics. -Kwok Last edited by Kwok_Yu; Jul 03, 2010 at 10:05 PM. Reason: deleted link
Jul 02, 2010, 09:48 PM
Registered User
Maryland, USA
Joined May 2004
2,641 Posts
Actually this one get you real close to doing the whole tip in one shot. I just scaled down the tip airfoil really small.

# Files

Jul 02, 2010, 11:40 PM
Registered User
Joined Mar 2007
484 Posts
Quote:
 Originally Posted by mack5 hi everone I been trying to draw curved wings for a f3b glider and some how I can not download the TIG's extrude plugins from the skup web page. I am getting a error message when I do. I regestred on the page but I can not down load any of the plugin. Does anyone have this plugin that I can use? Also how do you show the wing section, root and tip section for a curved wing? Big thanks Sorry for asking some of you off line such basic questions off line I do not wont to clog up this thred with basic questions Thanks

Here you go. Make sure you read the info on SKu Plugins forum and have the companion .rb's also.

Jim