C17 Globemaster III build - planking

Lots of planking, filling and sanding has been happening on the C17 forward fuselage section.  Here are some pictures, but they are a bit in reverse order I'm afraid!

The tailplane has had glassfibre tubes added to help guide the fixing bolts down through.  I *might* be changing the elevators, after having a chat with the PSSA guys, I think she might be a little lacking in that department.  I will make a pair of built-up ones if it comes to it.

Horus has landed.

My Horus has at last arrived.  I love it!  FrOS seems very capable, and they have a Github area where you can ask for additions or modifications to the software if required, which I've never seen another manufacturer do.  Loads of options for flight modes, and it'll even run an 8 servo wing with ease.  It even has a rotary position switch, which will suit the big quadcopter's changing flight modes.

An amazing amount of telemetry screens which is great for my big scalies, including vario, GPS, airpseed, voltage from up to 14 sources, temperatures, speeds, RPM etc etc.  Should be a bonus for when I get the Pik20 sorted for GPS triangle racing, and also super for the ASK18 when she goes up behind a tug again.

Time for some more programming!

C17 Globemaster III build - tail, odds and sods

Now that I am happy with the final fit of the tail section, it's time to cap off the tailplane.  I added a long strip of 3/16" balsa, and sanded it to shape.  I also went around the tail / vertical interface and filled in any small gaps, as well as boring a hole for the tail-top landing light, as you can see.

The white foam triangle that can be seen on the port wing that the tail is sat on, is a quick repair.  A long time ago when I started  to fit the spar boxes, I managed to push the steel spar clean through the box and mostly out the top of the wing.  Oops!  I cleaned out this blemish and fitted a new bit of foam in with gorilla glue.  This will then be veneered tonight ready for final filling.

In other news, I've got tracking information from T9 for my FrSky Horus today - yessss!  Can't wait to try out this new radio.

M55 Mystic build progress - plan drawing

I've laid up a quick drawing of the M55, as I need to cut a new wing centre section - it's the only bit missing from my kit of parts, and it actually gives me the freedom to make it quite strong and integrate a few tweaks of my own.

Just over 4.5 metres wingspan :)

C17 Globemaster III build - full assembly check

This weekend saw me get the entire beast together in the garden for her tail alignments - something that I've been chomping at the bit to get on with, but weather and circumstance have not been in my favour.

All went well, and the rear carbon sleeves are now glued up, and are being integrated into the rear structure as a whole now.

I eye-balled the structure, then checked with a spirit level which wasn't needed.  It all looks to be within an eighth of a bubble / half a degree after final tweaks.

I also managed to do some work on the Fouga and the Ilyushin this weekend, but nothing big enough or interesting enough for pictures just yet.

C17 Globemaster III build - flap canoes and winglets

Things are moving along smartly now.  

First off, I laminated 16 flap canoe plates with pink foam :

Then they were carved to shape, and laid out on the wings for a test fit :

That all looked OK, so I bonded them on, then ran some lightweight filler around the bases :

Whilst that was drying, I flipped the wing over, added the 3mm liteply face plate, and the foam trailing edge root part :

I've added a slot through canoe number 2 now, into the servo bay.  This was achieved with beaten up old bit of brass tube, heated and poked through :

So, some winglet action now.  I bonded medium weight balsa to 3mm liteply.

This was then sanded down both sides to form a semi-symmetrical wing section.  Whether that was the right thing to do or not, I don't know, but I didn't want to remove too much of the liteply as it is what gives this part it's strength : 

Balsa side :

In place on the wing.  You can also see the notch I've taken out of the LE for the wing tip light here :

Fouga Magister build - body filler time!

Some progress on the Magister - no I'm not just concentrating on the C17!  Time for some body filler on the tip tanks and fuselage end-piece :

First tank sanded down - lovely and smooth.  I might primes these at the weekend :

C17 Globemaster III build - spoiler and aileron progress

Whilst the wing is still in such an unfinished state, I thought it would be a good time to try out my ideas for the spoiler mechanism on the top surface.  I cut the spoiler itself from 1/16th" birch ply, then mounted it to the wing with a tape hinge.  I used one of the flat metal gear / digital Corona servos (5kg pull) screwed to the mounting plate for the trials.  A short linkage made up from M2 parts was made up, and we were off :

The wiring location is of course just temporary here.  I have yet to cut the final channels through the foam for these last leads.

So, with the aileron mounted too, this is what it looks like :

That should stop her in a hurry! 😚

So I removed it all, and then added internal brace-work to stiffen things up, and I will add hinge hard points to this too.  Getting exciting - I am very near to doing the final parts on this wing panel now.

C17 Globemaster III build - flap mechanism

I hot-melt-glued a flap servo into the wing last night, made up a HD M3 linkage, and played with some geometry.  

It works!  I need to make sure the flap side of the linkage is properly reinforced (I will wrap it in carbon), but essentially it works fine.  The servo will need some work done on it's travel volume, but that should be a doddle on OpenTX with my new Horus.

Now on to the aileron connection...if only I could find my left aileron!

C17 Globemaster III build - fuselage work continues

Getting things done before planking.  Carbon tubes to accept the joiners :

As above, but a side view now, showing local reinforcement webs, and former doublers :

With the joiner tubes attached (yes, most of this is being built on an ironing board, just like the A10!) :

Wing root fairing started.  I slid the wing on to the spar to position the outer "hard" ply face, then added 1/2" square balsa blocks for spacers :

This was then planked in 3/32" sheet, and sanded smooth.  I braced the ribs front and back with 1/2" square hard balsa :

The start of the tail section alignment!  The fin & tailplane is currently about 2 degrees off the vertical.  The tail section has been pushed roughly onto it's mating tubes, to get some idea of the overall alignment progress.  Next it'll be downstairs to get the wings on at the same time, then a few measurements will need to be taken.  Once happy and everything is square, I will bond the carbon sleeves in the tail section.

Oh, the nose foam has been sanded and also has received a skim coat of lightweight filler here too :

C17 Globemaster III build - some fuselage progress

After visiting the LMA show with the PSSA guys in October, I came to realise that the model's slow progress was more to do with the construction method, rather than the size of the model itself.  The wings are nearly done, the tail is done, the tail section needs final sanding, but the nose had stalled.

All that foam had gotten to me, and I hated sectioning it up / shaping it / sanding it / gluing it in / pinning it.  Then it still needs a lot of work to get to the final shape, then a semi-complex covering method!  So I decided to knock it on the head, leave the foam where it is, then stringer-and-plank it.

Some of the foam will be removed out the front, but the nose section is now going to be built up and planked with 3/32" sheet.

So then, enough talk - here are some pictures.

Stood on her "tail", undercarriage stringers being added

Some white foam has been shaped here, and some stringers added

On her belly again, stringers on the top

Some of this foam will stay, as shaping wood around here will be a pain

So, some progress then.  I have realised that a battery and ballast tray will need to be added up front ASAP whilst there is still access.

The 200th post

Well, here is the 200th post.  What to say?  Probably nothing, other than thanks for reading, and hopefully continuing to do so.  Here are some pictures instead!