Week 162 (2) - Flap drive and Canopy

Hours to date: 1460.5

Onto the dreaded flap drive job!

Well to be honest so far it has not been too bad at all.

First thing to do was put a 6mm thread into the flap securing bracket on the wings. Easily done with the drill method (as described in a much earlier post about the elevators). The manual is a bit confusing here as it states a 372mm distance in the text (between the trailing edge of the flap and the trailing edge of the wing) then states 370mm in the diagram. I went for 371mm.

To make things easier to move around I decided to put the Twister on all 3 wheels for the first time.

Onto the flap drive - I spoke to Johan in Belgium first to see if he could offer any advice or 'gotcha's'. As it turns out he described the method that I was going to use anyway but added something really helpful - thanks Johan!

That extra something was the use of a straight rod (or tube as in my case) as a device to get the holes lined up before drilling out to their final size.

As you will see below it worked out really well and I only have a 1 to 2mm gap in the safety cell holes to the flap torque tube.

The photos below better describe the method so please see them to understand how it was done.

I found out afterwards that the torque tube supplied was 24mm too long. A careful bit of measuring and cutting later had it to the right length.

I then riveted one end of the flap drive onto the end of the tube (as per the instructions). The other end is riveted on after the aircraft is painted.

I made up the flap torque tube drive and pre drilled my holes to secure that in the drive arm to make life easier later on.

Good news is - I finally got the Port wing on and the spar pin in. This allowed me to fix the rear wing pin bearing and also fit the front wing pin bearing after that. All that's left to do now is fit that wing to the fuselage (by filling the gap with flock).

The starboard wing has not proved so straightforward. I spent the better part of a day trying to get it to fit and ending up finding out it was the front wing pin that was fouling on the wing inside. I've fixed that and it should be okay to fit now.

But before I do I'll need to fix the rear wing pin bearing on that side too as I found out that it was 1mm out. So the lesson here is - do not fit your wing pin bearings in the factory drilled holes! Wait until you can put your wings on and do it then.

I'll end this post by talking about the canopy. 

I've made up the retaining cable - using a Swaging tool for the first time - things worked out good.

The manual states that you need to fit two threaded hooks (one in the canopy frame and the other onto the fuse on the inside) as securing devices for the retaining cable. Guess what? They were not included on my kit so I had to make a trip down to my hardware store to buy some - best to do this job before fitting the perspex to the frame as it would be impossible to drill a pilot hole afterwards.

After many many hours of fitting the perspex to the frame I was finally ready to bond it in place - a very long and frustrating job doing the fitting - take your time and be patient (lots of sessions rather than trying to do it in one go).

I masked off the canopy frame (where it was painted) with duct tape.

I also masked off the inside of the perspex - where I had previously put masking tape (as a guide of where to key up the edge to be bonded).

Finally when all of this was done and the frame was cleaned with Acetone - and the perspex with meths (do NOT use Acetone on the perspex it will graze it and most likely melt it!).

Following Pete's advice I carefully drilled 4 holes into the perspex and frame on the 4 corners (1.5mm holes) for some securing nails. These are then waxed for releasing.

Then I mixed up a heap of flock (175 grams to be precise) and put that all around the frame edge where the perspex would bond to it. I thought I had overdone the flock and put too much on but it turns out that was just the right amount - I only ended up scrapping about 25-35 grams off afterwards.

With the help of my brother we lowered the canopy carefully onto the frame - lining up with previously marked lines front and back.

After that I just gently pressed the frame in all round and then crawled inside the fuse (through the baggage bay end hole) and scrapped off the excess flock on the inside with a sharpened stirring stick.

As you will see below one area would not sit flush with the frame so I resorted to gently pressing it in place with a block of wood while it set.

We'll see how it all turned out next time I post!

6mm thread cut into the flap securing bracket.

On all 3 wheels for the first time!

Determining position of holes for the flap torque tube by putting the end attachments on the flaps and sliding the wings on and marking where they touch on the fuse root.

Using a straight tube to determine where to drill out the safety cell hole - remember that the fuse wing root is not straight - dihedral! Use a spirit level to get the tube square.

Broader view of above

Factory marked hole is pretty much spot on this side - miles out on the other side

Fixing the port wing rear wing pin bearing

Use the cut out from your hole saw of the outside hole to mark the inside hole in the safety cell

Tube in place with 1-2mm gap all round.

Note how flap drive sits square but wing root has angle for the dihedral

Flap torque tube was too long - by 24mm

Port side riveted to the torque tube

Flap drive motor and arm assembly made up.

Port wing pin finally in!

Flap drive in place - arm will be riveted later.

Flap drive 'box' in place.

Swaging tool - poor mans version but works okay

Canopy retaining cable made up

Ditto - with heat shrink on the ends.

Canopy retaining cable threaded hook and securing nails for the canopy fitting job.

All masked off and heaps of flock applied to the frame edge

Leaving it to set with block of wood for stubborn area.

Arrow shows where nail is - these will be removed later and the hole filled.

Week 162 - Canopy Part 5

Hours to date: 1433.5

Sorry for the big gap in posts but I have had my parents over visiting from New Zealand, so things have been rather hectic for me.

Onto the canopy.

The opening and emergency release mechanisms are both completely finished.

As you can see below I decided to paint the emergency handle red - I think it helps with other pilots who don't know the aircraft not to pull on it - it will of course be placarded also.

On the emergency release side I struggled to drill the hole for the roll pin that secures the handle in place. The release pin is made from stainless steel which is notoriously difficult to drill. I only have a hand drill (a drill press is much better) and even though I bought some Cobalt drill bits they didn't work. I then bought a Carbide drill bit and I made some progress with it before I work hardened the steel. Feeling a bit frustrated by this point I ended up taking it to a local engineering shop and getting them to drill it and fit the roll pin. It is one of the very few jobs I have not done myself on the kit so far. (I actually fitted two roll pins - one either end of the handle - just to be sure).

Once the handle was painted I fitted the release pin back into the fuse and bonded it in place with carbon and flock (this was only on the fibreglass tube section that the pin slides in).

After that I flocked the panel that had been cut out of the side of the cell back in place and then put one layer of glass over all the joins with a 50mm overlap.

On the opening side I have painted the metal parts black - and left the parts that slide into the mechanism bare (they are stainless so will not corrode).

Everything works well - the opening is easy, with no play and the emergency release has a nice hard 'pull' to it which is what I wanted. Use WD40 to lubricate these mechanisms but only after they have been bonded and painted.

The only thing left to do is bond the canopy perspex to the frame - I have spent many hours so far fitting it to the frame. Still a little more to do. I have used a hand sanding method as I don't like the idea of putting a power tool on the perspex. Pete says he uses an 80 grit flexible sanding disc on an angle grinder. I don't have an angle grinder so I am resorting to the 'armstrong' method of hand sanding.

I am finding that the more you do the more you have to do (if that makes sense) as the canopy settles onto the frame. It's not a job you would ever do in one hit - best to have several sessions of it, taking a little off each time as you go.

An update on the frame fitting to fuselage. I thought I had added plenty of micro to the fuse before putting the frame on - and indeed it did ooze out of the sides all round on the outside - but as it turns out I did not add enough on the inside area. Not a major hassle as I just had to have 2 goes at doing this job. Adding more micro to the fuse and giving the frame another wax on the packing tape before closing it down. With the waxed packing tape it released very easily.

I've moved onto the dreaded flap drive job now (which Pete says is the worst job on the whole kit) so will post an update on that soon.

Rear of canopy fitting very nicely to fuse now with micro added

Ditto at the front

Fuse has micro added around the canopy area and lightly sanded - ready for paint

Beginning to fit canopy to frame - don't do it off the plane as I started to do here!

Emergency release bonded in place and the cutout panel flocked and glassed over

Opening mechanism all done

Emergency canopy release all done

Solo Twister display

Last weekend I saw my first ever live display by a Twister.

Pete was not flying as he was on his way to China to display.

As you will see Jon Gaudy puts on a masterful piece of flying despite the tricky blustery conditions.

Enjoy!

http://youtu.be/sQbnjO7Bhv0?list=UUOkKIXmP2rkfDA6hHGjTu6g

Week 159 - Canopy part 4

Hours to date: 1401.0

Yes folks I am now past 1,400 hours.

Will I be true to my original guesstimate of completion in 1,500 hours? 

In a word, no.

I feel I may have another 600 to a 800 hours to go.

Progress has been made on the canopy but in the meantime I decided it was high time to try out the cockpit paint - so I had a go at the seat and baggage tray - as well as the inside of the frame of the canopy.

Two coats brushed on - one after the other - with the second coat being stippled on. Everything turned out well, so this bodes well for the cockpit.

I phoned Pete to ask about taking the play out of the emergency release pin. He told me exactly what I was thinking to do anyway which was good. Wax the pin then put runny flock around the hole. I used a small syringe to squirt the flock into the cavities - I can't imagine trying to do this any other way.

I've started fitting the counterweights to the ailerons too.

On the canopy I am waiting for a cobalt drill bit - 2mm - to drill the release pin for a roll pin that will lock the opening handle in place.

So while I wait for that to arrive I decided to fit the canopy to the fuselage. Actually it is the fuse that gets fitted to the canopy as that is where the material is added. In this case Micro.

We'll see how that turns out next time I post.

Seat painted

Baggage tray painted

Syringe with runny flock

Release pin with flock to take out play 

Ditto at the back

Aileron counterweights

Fitting canopy to fuse at the back

Fitting canopy to fuse at the front

Two Lancasters

Nothing to do with the Twister I know but these two flew over our village the other day.

As they are the only two left in the world in flying condition I thought it too good not to share.

http://youtu.be/QglGtazTGvQ?list=UUOkKIXmP2rkfDA6hHGjTu6g

Week 157 - Canopy Part 3

Hours to date: 1378.5

Well, this canopy is taking a while isn't it.

I'm taking it quite slow as I don't want to screw up anything.

I'm quite enjoying the small, fine detail work required on this job. 

Also when it's done it will be something that's right in the pilot's 'eye' whilst sitting in the cockpit for long hours. So for me it would upsetting every time I looked at it if it was not done as well as I can do it.

Once the Opening side hinges were shaped to fit I superglued them in place.

After that 3 layers of thin glass were laid up over them, overlapping onto the frame itself.

Once set, the centre section is removed and used for the hinge part that is attached to the fuselage.

I made up some carbon blocks by supergluing some left over sheet together and sanding to shape. These are to support the hinges on the fuse.

I then filed some small trenches for them in the fuse and flocked these in place (with the canopy closed and clamped down - to set the position accurately).

After that another 3 layers of glass were applied and overlapped over the hinge part. 2 layers of Carbon was used to cover the rest of the holes made in the fuselage.

I made up some shaped blocks of foam to go on the carbon while it set - so that they took on the correct shape 'trench' like (obviously these were on top of the peel ply so they did not bond to the carbon).

Just a little more tidying up to do on the opening side and it will be done.

The frame itself is now almost done too with all the cavities finally filled.

The emergency release side is getting closer - hopefully I'll have that done by the next time I post.

Hinges shaped and fitted, just about to super glue them in place

After super gluing in place

3 layers of glass have been applied and marking show where the centre section is to be cut out.

With mechanism in place - works nicely.

Ditto at the back

Carbon 'blocks' made up to support the fuselage part of the hinges

Foam blocks taped in place to conform the carbon to shape.

Rear hinge - not too shabby

Some more finishing to be done here to make it perfect

It's a bit rude

What is believed to be the first such figure of it's kind, made in the sky over Cambridgeshire by the Twister Duo recently.

Week 155 - Canopy Part 2

Hours to date: 1359.5

Back from my hols now and getting on with the canopy.

When cutting out the hole for the release mechanism I managed to forget about the rudder cable guides and ended up nicking the side of one - not a big deal - I'll repair with with some tape, just as well I didn't cut through the whole thing!

The hinges on the emergency release side are on and all finished now - pretty pleased with how this turned out. Then I realised that the order of tasks Pete had told me to do was messed up. I should have bored out the holes for the release pin first then bonded in the hinges with the pins inside. Instead I'm having to do it the other way around.

Rather than work blind on boring out the holes for the pins I decided to drill a small hole in line with the hinge holes. This will be easily repaired afterwards with some flock.

Also a trench has to be gouged out to allow for the release mechanism.

Lots of work to get to this stage of just sorting out the pin holes - about 7 hours worth.

But it's done now and just needs a little tweaking to make the action smoother.

So I've switched back onto the opening side - and started to shape the hinges that will be bonded onto the canopy frame.

Hinges fitted to frame

Ditto - view from the outside

Small holes for alignment of the bore holes inside (for the release pin)

Pin bores and trench done for the release mechanism

Release mechanism in place

Finally getting there!

Onto the opening side now - sizing up the hinges for fitting to frame

 

Week 151 - Canopy

Hours to date: 1346.5

As you can see below I've made a start on the canopy.

It seems to be going okay so far.

The copious notes and many photos I took seem to be a great help.

The frame does not fit the fuse very well - it needs to be clamped at the sides. Even then there is still a gap at the front and back - so that will have to be sorted out with micro to the fuse.

The frame also has a heap of air bubble cavities in it - again these will need fixing with micro.

On the throttle I found after installation that it was rubbing on my thigh - due to the angle of the cell it was flocked to. This is no good and I was thinking I may have to rip it out and start again. I left it a night then had the thought to just bend the throttle lever outwards a little - so this is what I've done. The brake lever is fine where it is (just as well as that couldn't really be bent as it is double the thickness of the throttle lever). 

Something to bear in mind if you have not installed your throttle yet - perhaps a good idea to allow for this. If I were to do the job again I would build a wedge of flock on the cell first to get the angle better. Wise after the event as usual!

I'm not sure I will do another blog post for a few weeks as I'm off on holiday to India and Sri Lanka next week.

Canopy frame just sitting on fuse - massive gaps.

Loads of cavities to fill on the frame

Fits better with clamps - determining the position of the cut outs for the hinges here

Figuring out where to make the cut outs for the opening mechanism

Packing tape for a release of the hinges on the fuse

Cut outs getting there...

Flocking in the hinges to the frame

Ditto

Week 150 - Pitot tube and throttle assembly

Hours to date: 1336.0

A very quick update this week - as I'm super busy at work.

With the help of the 'grabber' I was able to secure the pitot tube line to the back of the wing spar. I used the same 'U' shaped fiberglass brackets I've used previously for the rudder cable tubes.

I've also fitted the throttle cable and bonded in the throttle/brake assembly (using copious amounts of flock) I'll be adding two bolts and nuts to this later as an extra securing method.

More detail on all of this next time I post.

Pitot hole fixed up with flock

Pitot line being fixed to rear of main spar

Throttle/brake assembly bonded onto bottom of safety cell.