Ivan Pettigrew Twin Otter 480 Build - Page 3 - RC Groups
Thread Tools
Nov 23, 2008, 07:51 PM
Registered User
I found first couple mistakes in the files I posted.

Of the vertical fin formers, F1 needs to be 1/8th, not 1/16. F2 was missing completely so I added it in the 1/8th bin. I also added some fillets to help align the formers at the correct angle to the TE of the fin.

New V2 of files posted here, and V1 has been removed. I will continute to make adjustments if I find something wrong as I build. Cheers!
Sign up now
to remove ads between posts
Nov 23, 2008, 09:56 PM
Registered User
Gonzo007's Avatar
Very cool. I have a set of 480 plans and was going to build one. But I would rather start with a lasercut plans. I would recommend beefing up the tail a bit. I own the original 600 size one and the tail has twisted. I hope to have time this winter to fix it.
Nov 23, 2008, 10:22 PM
Registered User
Quote:
Originally Posted by Gonzo007
Very cool. I have a set of 480 plans and was going to build one. But I would rather start with a lasercut plans. I would recommend beefing up the tail a bit. I own the original 600 size one and the tail has twisted. I hope to have time this winter to fix it.
Which part of the tail ended up twisting? Fuselage? Stabilizers?
Nov 24, 2008, 09:25 PM
Registered User
I added some reinforcement for the nose gear area including cross-braces per the plan, and doublers on the bottom. I'm using a spare 1/2A dubro nose gear mount and will bend my own wire to meet the plans. I mostly used Gorilla glue here for the gap-filling foamy effect.

I also finished sheeting half the bottom.
Nov 24, 2008, 09:36 PM
Registered User
The next step that I've been putting off is building of the vertical stabilizer. Because it's profiled, its not as easy to pin to the plans. Heres the steps I used:

1. Take 3/16" stock and cut trailing edge piece that is the width of the widest part of the tail. In this case 7/8" was the widest at the aft of the fuselage.

2. Measure and mark the former stations on the TE according to the plan. Repeat for leading edge stations. Also draw a line up the midpoint of the trailing edge piece.

3. Make angled fillet to align the bottom former to the LE and TE. Then I used the laser cut vertical fin tip to complete the outline of the fin and pinned it to the plans with the LE hovering above.

4. Mark the centers of former at the TE, and line them up with the station markings on the TE. Pin and glue.

Pictures:
Nov 24, 2008, 11:07 PM
Registered User
Jeff
I Am Enjoying The Build Thread. Is There Another Way Of Sending The Cut Files.. I Dont Have A Program To Read Dwg Files. Thanks
Carl
Nov 24, 2008, 11:19 PM
Registered User
Quote:
Originally Posted by CARL SCHIMNOWSKI
Jeff
I Am Enjoying The Build Thread. Is There Another Way Of Sending The Cut Files.. I Dont Have A Program To Read Dwg Files. Thanks
Carl
The .dwg is the cut file. There are free viewers available.
Nov 25, 2008, 03:36 AM
Student of Ivan
mountainman2442's Avatar
Jeff,

Looking good!

Your framing method for the fin is a very good idea. On all my Ivan builds, I have preshaped the spar prior to framing. This then requires some imaginative shimming/pinning to get the ribs aligned. Never occured to me to do this after the ribs are attached.

I'm working on converting all the parts into correct sizes for the 600 size Twotter in CorelDraw. It will probably be a few weeks but I will post the cut file once it is finished for anyone interested. Importing a .dwg file into CorelDraw results in some funky looking shapes that required a bit of smoothing but since I have zero experience with TurboCAD, I felt more comfortable editing the file in a CorelDraw thanks to what I've learned on Milfahre's Gull thread.

John
Nov 25, 2008, 12:20 PM
89" Kool Aid drinker.
Smash McCrash's Avatar
You have my interest as well... Always liked the Otter.

Mike
Dec 08, 2008, 09:50 AM
Registered User
I spent some time this weekend working on the Otter. I finished the vertical stab and almost completed the front hatch.

Here is the vertical stab. I decided to depart a bit from the plans and I capped each former with a thin sheet of 1/16" balsa to add some strength and make it easier to cover.
Dec 08, 2008, 10:02 AM
Registered User

Looks what has hatched...


I've been procrastinating on building the hatch because it is one of the busiest areas of the plans. I found it difficult to discern some of the details and when I cut pieces 5D and 5E from the side view, they did not line up with the top view. In the end I mostly winged it, and it turned out okay.

I started by building the frame of the hatch in place using saran wrap on the fuse to prevent gluing the hatch and fuse together.

Then I cut the pieces that form the forehead/roof of the cockpit and sheeted that. I added support window-frame struts to the 1/8'th hatch sidewall.

The bulkheads, longeron, and sheeting were added next, but I found that the window-frame struts I started with would be in the way of the sheeting, so I cut them free and secured the sheeting hatch to the fuselage with tape.

I sized the window frame correctly using 1/8 x 1/8 square sticks. To make the bottom of the front window I soaked some squares stock and curved it around the sheeting between the vertical sticks that form the window. It all looks a bit messy, but balsa-filler cleaned up the gaps and made it look a bit better.

Anyway, here is lots of detail shots, so hopefully the next n00bie to build the Twotter gets some ideas.
Last edited by JeffElecRC; Dec 08, 2008 at 10:10 AM.
Dec 08, 2008, 10:42 PM
Registered User
Gonzo007's Avatar
I agree with doing the caps on the tail. But I would put some more strings in to help with strength. I am cutting off the tail on the original because of a large twist.

Colin
Dec 08, 2008, 11:09 PM
Registered User
I could add some diagonals between formers.
Dec 08, 2008, 11:10 PM
Registered User
Gonzo007's Avatar
I will take a picture of the tail now and show you what can happen if you don't beef it up.

Colin
Dec 09, 2008, 12:58 AM
Registered User
LukeZ's Avatar
Quote:
Originally Posted by JeffElecRC
In the end I mostly winged it, and it turned out okay.
That sounds about par for the course on an Ivan build! The good thing is it makes you more confident and indepedent on future builds.

It's looking really good!


Luke


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Link Ivan Pettigrew Planes - Build Threads and Videos LukeZ Scale Kit/Scratch Built 3393 Sep 15, 2017 02:08 PM
Build Log Yet Another Ivan Pettigrew Short Solent 480 MattZC Scale Kit/Scratch Built 622 Feb 21, 2017 01:50 PM
Discussion Ivan Pettigrew Short Sealand 480 -New Video Added flypilot Scale Kit/Scratch Built 79 Jun 07, 2008 12:33 AM
Discussion Slow Build Thread for RT models Ivan Pettigrew De Havilland Mosquito Gonzo007 Scale Kit/Scratch Built 13 Jun 01, 2008 06:36 PM
Beldone Twin Otter Buran Scale Kit/Scratch Built 8 Jun 21, 2006 07:18 AM