Fuselage - From Truss to F-2

Started the front half of the fuse from the truss frame forward. Fairly straight forward construction but there are a few tricks.

1. Place the truss frame upside down on the plan (the top facing the plan). Cut the hardwood stringers that attach to the top of the truss frame (make sure you leave heaps over on the engine end of the cut)


2. Once you've attached the hardwood stringers to the truss you can now turn the whole assembly back up the right way.


3. Next to fit is F-2, and the ply sides. I also fitted the doublers. Pretty straight forward.


4. Now it's time to join the forward assembly to the truss. This part had me stuck for quite some time trying to figure out how it all fits together. This is because the ply sides must be straight because the wing mates to the fuselage at this point. Thanks to some help from the other side of the pacific from a fellow Pawnee builder (you know who you are), and another mate from the flying club we devised a method of joining the fuselage.


5. Basically, I cut a piece of ply to match fuselage space from F-2 back to the truss to ensure that everything squares up.


6. Then I clamped the whole assembly together and epoxied one side at a time to the truss.

1. Now you can glue up the top and the hardwood stringers to match the outside because later you'll sheet the whole thing in 4mm balsa.
2. I also added some extra triangle section stringer doublers (for want of a better description) inside the truss join, and the hardwood stringer joins etc.
3. Now you can fit F-3 and F-3a at the same time. The later two being quite simple. You can now glue up everything including the ply sides and F-2.
4. Now glue up F-3 and F-3a, make a little jig from some scrap matched to the slant on the plan and use that to ensure that F-3 is mounted at the correct angle.

Now go and have a stiff cup of coffee, I'm sure you'll need it after having that. Next we tackle F-1 and F-1A eeek!

Stay tuned.

Fuselage - Truss Frame

I've started with the truss frame for the rear of the fuse because that's the hardest part. I figure it's all going to be down hill from there.

Mate, was I right. The plans are a little confusing and the frame is also confusing, at least for me. Perhaps it was the late night?

Either way the frame sides are built in the standard method over the plan. Make sure that you mark the position of the cross members onto the upper and lower longerons and also mark the positions of the fuse formers on the upper longeron. This will make life much easier when you assemble the truss.

Once you've made both sides and marked the postions I mentioned above I would make the cut to the rear of each side to facilitate the joining of the halves in the next step.

Join the sides of the frame on the bottom first. Use the shortest lines (long ways) on the plan to line this up when doing the join. I suggest gluing the rear of the frame, then cut and glue the farest end cross member and then work down towards the back from there. Once you've got all that done, I suggest putting the tailwheel mount (ply) and the underside planking (balsa) as this will hold the whole frame true for the next part of the build. Make sure you leave some planking out from the side so that you can sand them down once you're ready to finish off.

Now the tricky part! When you do the top cross-members you need to line up with a different set of lines on the plan. The longer lines strangely enough! This may seem self explanitory to everyone but me, but I think it's worth mentioning so you don't have to build two truss frames like I did!

Follow the same method and cut and glue the fartherest cross member first, then move towards the back.

That's it for the truss. Next we'll be doing the first of the formers and building the rest of the front onto the truss.

Pawnee Has Begun!

I've started work on the TM RC 1/4 Scale Pawnee tonight. I'm going to blog the build here as I go through it. I'm intending to use the Pawnee as an AeroTow tug plane once complete, and have also aquired the hopper kit for a bit of fun and demos at model airshows.

I've had the kit for sometime now lurking in the shed waiting for me to start construction. It's a very complete kit as far as parts go, but it does lack in a few aspects which were a little disappointing given the cost of the kit.

1. No build manual. You would think for a kit of this size and quality that there would be a build manual. I bought the TM R/C Pawnee kit because of the quality of the other scale glider kits that he has and the detailed build manuals that come with those kits. That being said, I don't think there's anything in particular that would present a major hurdle, at least that's what I thought before I started building!


2. All the ply parts are included, but you need to source a far amount of other balsa and spruce stock to complete the kit. Not a huge deal, but is a pain because of the lack of long balsa stick shapes these days.


3. Plans are confusing. The build is based upon a design from the 80's and consequently the build process and design is a little outdated and the amount of wood and size of the stock used in some of the construction is a little overboard. These days with composite construction methods so easily available, more use could be made of them. One thing it has going for it though it's going to be STRONG! Good for a tug!

Of those 3 points the only one that I'm really disappointed about is the build manual. I've built a number of kits over the 15 years I've been modelling and this would be the first one without any instructions whatsoever.

Anyway, onto the build! Stay tuned!