K5682 - Martyn's Fury

[Danny Fenton]

Coming along nicely Martyn

Cheers

Danny

[Martyn K]

Been working on the upper wings and ailerons. All a bit deja vue - sorry about that

Upper right and centre section under construction, following the same method used for the lower wings. However, we do have the ailerons to consider now. One thing I hadn't spotted was a lack of holes for aileron leads - not a huge problem in my case. I am going for these metal gear thin wing servos mounter outboard.

The problem is that they are slightly too wide for the rib spacing and will to straddle a wing rib.

Getting the wing tips to fit is still quite tricky. This one is wrong and needed moving up be about 4mm - I misread the plan. Now corrected

The TE at the aileron extends one bay into the root section but the plan wasn't clear how to do this. I don't like leave pieces of wood floating so I extended the piece of wood across the full bay but tapered it down so it wont protrude into the covering

The joiner tubes fitted to the centre section - same as the lower wing

Clamped up while the epoxy dries.

one problem though is that the holes for the cabane strut screws are right where the tube is so I have had to redrill about 3mm lower. I think they will be ok.

repeat for the Upper port wing

Set the dihedral

One thing I am having trouble with is getting the ribs to glue reliably to those ply doublers. tried sanding them etc, no avail.

A bit of detail at the wingtip. Still having problem getting those 3 tip ribs to locate correctly. The inner two need trimming back to suit the aileron so my theory about them being correct for the upper wing was wrong..

Another problem I spotted is that some of the ribs lifted very slightly after I glued them. Something to watch for, its not obvious unless you see it enlarged on a photo.

3 wings in the process of having cap strips added, the 4th on the board

Also made a start on the ailerons. I used 1/16" contest grade quarter grain for the cores. I built the underside first - cut the outline then mark the rib positions top and bottom. All those little triangles are a bit of a pain. In hindsight, I wish I had used 1/8 square balsa and simply sanded to shape. The difference in weight would be indiscernible.

The upper ribs added and the curved tip treblers. 3mm balsa end rib will be sanded back to shape

The LE is very light 12.5mm balsa with the sanded away area marked so I dont do something stoopid.

I have precut the slots for the aileron hinges using the bandsaw. I'll shape the LE the remove the slots when I am happy with the shape. There is no glue (hopefully) behind the slots so they should tease away quite nicely by completing the cut with a scalpel

That's about is..

More to come. Looking forward to starting on some other bits as long as its not wings

Martyn

[Martyn K]

At the visit to the IWM last week, Danny spotted that the full sized had riblets, top and bottom wings. These are not shown on the Bryant plan. Common sense said ignore em, OCD said otherwise. In the ensuing argument Common sense got a black eye and OCD won so I started retro fitting riblets

Used the plan to cut a 1/16 ply template that goes about 4mm under the sheet and butts against the front spars. I am not putting cap strips on the riblets to they are cut 1/16" over size top and bottom

Although they are mainly cosmetic, they do offer some structural benefit by supporting the bridge on the 1/16" balsa LE sheeting

I'll need to make this joint between the centre panel and the outer panels a lot worse to be just like the real one..

and believe it or not the first dry assembly of the upper wing. Just about to fit servos and servo extension leads then I can finish the ca strips. The shroud over the aileron will be 1/32 ply - I need to buy some ply..

More to come.

Meanwhile back to cap strips. There are a lot of them..

I also need to get on with the Rearwin Speedster as well

Martyn

[Tony Bennett]

fantastic work young man.

Tony B

[Martin McIntosh]

Going to watch how this goes Martyn. Very ambitious. One of the best looking aeroplanes ever built.

[Jose L. G.]

Nice build.

Encouraging to begin with my wings.

José L.

[2W]

Watching carefully Martin. I'm aiming to start on the wings next week. Keep up the good work!

William

[Martyn K]

Thanks all

I finished retro fitting the riblets in the lower wing last night and while the glue was drying I made a start on the brass bits (Thanks Ernie - you have made life much easier)

Removing the brass parts - in this case the rigging wire points was easy with a hacksaw and then file them smooth. Bending was simple using a pair of parallel action pliers. The brass bends very easily.

I used Kevlar thread for binding - its isn't going to break. Don't forget the infill between the spars. The ply cover plates and strut locating pieces glued in using epoxy and then clamped and allowed to dry overnight. The lower wing fittings were glued in this morning.

That was fairly straightforward. Now I made a start on the bit that I was dreading. Getting the servo to fit..

There really isn't much space. I have gone for slimline servos normally used in the wings of a glider. A 3mm birch ply mounting plate has been cut and one rib slotted from underneath as far as I dare.

The front of the plate butts up against the web - I knew it would have a use but at the moment it is just resting in the slot while I have a think. The ribs will need reinforcing and the servo mounted on grommets.

There really isn't much space... I darn't cut the slot any lower.

There will be no access panels. The servo will be fitted as seen.

Still pondering...

More to come on this...

Martyn

[Martyn K]

Some comments and thoughts from my FB blog

1. The brass rigging parts are only bent through 90 degrees at the moment. If you bend them fully then the 1/16 ply plate wont fit as the bend needs a step in it. SO bend at 90 deg, allow the epoxy to harden then finger bend the last 45 degrees. Its no problem, the brass is nice and soft

2. The plates need a spacer underneath them to cater for the thickness of the brass plate. It needs a much thicker spacer under the lower wing forward rigging mounting point as the gap between the spar and the cap strips is much bigger. The plate sits flush with the cap strips

3. I used parallel action pliers and bent all 4 in one go so they are the same length. The absolute length isn't critical

 

Martyn

 

Edited By Martyn K on 01/11/2018 11:37:12

[Martyn K]

A bit more progress - still working on the wings.. Lots to do here and I am now getting to the tricky bits

I forgot to add holes in the ribs for the aileron lead so I simply slotted the leas in about 5mm behind the main spar. Added cap strips on top

The shroud was fitted - cut from 1/32 ply with 1/32 balsa behind it. Now added this to the other wing half which is only getting changes and bits added as I prove them first,,,

I bit the bullet and have fitted the servo. Its actually sitting on cut down square grommets and a ferrule, The ferrule wasn't long enough to get to the top half. As its out in the wings I think it will be OK with this minimal vibration damping. I am going to link the pushrod using a M2 ball link. As the servo arm is quite short, its important that there is no slop at all

With the servo and servo lead in place I could complete the upper and lower cap strips. Just one more wing to go.. Its been like pulling teeth.

I mentioned that I was going to move the lower flying wire anchor point into the centre section. Cut from some old 20g brass sheet (a thick Tee section) and glued and screwed down. A short length of 1/4 x 1/16 spruce over the top will slot (hopefully) into a slot in the lower wings. That will be fun trying to get an invisible joint..

A funny angle shot. When dry, I can complete sheeting the centre section. The lower side is done and the uc plate has been added (as per plan)

Which brings me to the tricky bit. The first aileron hinge. Apologies if I spell this out, it too a bit of thinking about.

First cut out the GF parts then cut slots in the TE section of the wing. Note the most outer of the hinges needs to be shortened - the plan shows it sitting between the two spars but that is now filled with balsa.

From Chippie experience, it is best if the 10BA bolts are run in brass bushes, The challenge is to get the 4 hinges all lined up with a rod that can be removed afterwards. The end hinges actually butt up against the end ribs (at both ends so you cant simply slide a rod out.

Mine telescopes. Using the bushing tube, I cut 2 x 150mm length and a short length of piano wire to sit between them Cut a short bush to fit in the outer hinges and slot a 10BA bolt through and then lock not to keep it square and a bit of slow set epoxy over the head

Sorry its out of focus - having phone problems. You can see the 1/16" wide bush if you squint and have a vivid imagination.

Assemble the hinges and telescopic alignment rod. It needs to sit against the upper edge of the rear spar - quite easy. add slow set epoxy and slot it all into place

Alignment is quite easy using the Mk1 eyeball. Just make sure you don't bend the tubes. The hinge centre line is just behind the shroud. Leave it all to dry for a few hours then remove the alignment rod by sliding the piano wire into one of the tubes and there should be enough space to ease out the tubes from the hinges. I'll find out if that is true later

More to come

Martyn

[Martyn K]

Continuing with the aileron. this is really quite slow but I want to get it right..

The other parts of the aileron hinge were extracted and drilled - and then panic ensued while I lost one for an hour.

What is clear is that it will not be possible to fit the bolts, nuts and bushes once the aileron is attached so each hinge was assembled, bolted up (and the 10BA nuts secured with superglue) and the aileron slotted onto the hinge. Because I wanted to set the aileron linkage, I simply tack glued the aileron part of the hinge into place while I aligned the linkage and aileron horn. When the aileron has been covered and painted then the hinges will be slotted into the completed aileron. I am adding simple guides so the hinge is located correctly

I have moved the aileron horn in two bays as the location shown is incorrect on the plan. I also wanted to get the linkage angle so that it resembles that on the full sized. I am using ball links here again, but I have carefully sanded the plastic bit down to a slight taper as was rather bulky and was fouling the woodwork slightly.

 

The outer hinge has had a couple of strips if 1/8 x 1/16 balsa to stiffen and strengthen the area around the hinge and add a little glue contact area

 

 

The aileron linkage bends are a bit contorted but its a slow flying aeroplane and not heavily loaded. It seems quite stiff so I think it will be ok.

 

And the proof of the pudding. Although differential has been built in mechanically, I can add extra if required from the transmitter controls, but the throw looks about right.

 

The other bit of progress is that I have completed all the cap strips, fitted the LE and started sanding to shape.

 

More to come

 

Martyn

 

 

Edited By Martyn K on 06/11/2018 09:50:50

Edited By Martyn K on 06/11/2018 09:54:21

[Martin Fane]

Martyn

Excellent progress. Great guide for the rest of us.

I'm not looking forward to building these wings

Martin

[Martyn K]

Thanks Martin

The wings are OK, its just very repetitive work. The aileron hinge and servo linkage is the trickiest part so far. I have made mine more complex by having a 2 piece wing but now that it is done, I am not sorry that was the path I chose..

Martyn

[Martyn K]

Can't believe its a week since I last posted.

Still working on the wings.

All cap strips done (yaay) and generally tidied up.

That's the upper wing with the ailerons temporarily fitted

And the ailerons go up and down quite nicely

Upper and lower wing with most of the sanding done, ready for a polish. The trick of using double cap strips on the outer wing tip ribs and then sanding back to profile seems to have worked quite well

A slightly out of focus shot of the flying wire rigging point - built into the centre section but extended into the outer panel. A small balsa enclosure has subsequently been built around this to attach the covering material. Which I still haven't fully made up my mind what that will be.

Ready to make a start on the tail surfaces next but that will have to wait for a few more days as I am progressing the Rearwin Speedster.

More to come

Martyn

[Martyn K]

The Speedster is ready for paint and we don't have Shawbury available yet for indoor flying, it has taken the pressure off that. However, I have started another model (a classic F3A) in the past couple of weeks to fill in time while the glue on this dries.

As I am now about 2 months behind you all, I have made a start on the tail surfaces.

and

The tailplane has mainly followed the plan for construction, all went together very easily. Amazing how much strip wood has gone into those ribs..

All very straightforward so far.

After visiting and photographing the real Fury at Duxford, I decided that I would try and emulate the hinge methods as used on the full size

so an evening was spent cutting a few rings

6mm carbon tube used for the rod. I was tempted to put a full length rod in for the elevator but eventually decided that would be too heavy. So each stub is about 25mm long

A test fit before I finished the elevators in case I decided to scrap the idea. The only change I made was to lengthen the length of the reinforcement behind the stub as the spars were collapsing when I was cutting the slots and hollowing them out

With the elevator finished, the stubs were carefully glued into place

and

at the moment it looks like that while the epoxy hardens. I need to cut the slots in the tailplane TE and finish off sanding it all to shape. I am making the front edge of the elevators slightly narrower so that the relationship between the pivot rod and the covering is more scale like.

The elevator halves will also be linked by a short length of carbon tube. However, I am going to use a double closed loop system for both elevator and rudder controls.

The fin has also been built but I haven't got round to do the hinges on this yet. These are actually more complex and the rod culminates in the HF aerial mast

Sorting that out will be the next major task..

Really enjoying this build...

[Martyn K]

A bit more progress.

The tailplane has now been slotted for the hinges and it seems fine. Quite happy with that

The past couple of days, I have been working on the fin and rudder.

The rudder hinges (on the full size) are a little bit more complex than the elevator. Its a sort of double take. At first glance it looks like they are hinged on the tube rudder post but that is not the case. the hinge is actually a small bolt hinge just in front of the rudder LE. a plate from the rudder post sandwiched between 2 plates from the TE of the fin.

So..

I made 3 sets of these. 1.5mm GF and a short length of 6mm carbon tube to fit the slot that I will cut

Sorry for the crap photos - they are quite small (8mm wide) and my new phone macro facility isn't as good as the old one.

The pivot holes were drilled out for 2mm brass tube bush which was used to align the fin side of the hinges. In this photo you can also see a carbon fin post that will support the rear of the fin, dropping into a pseudo ali box at the rear of the fusealge

The fin side of the hinge needs recessing further = about 2mm as the gap is too wide. The hinge line needs to be just on the LE of the rudder. There is also a small piece of GF board packing between the plates to get the correct separation for the rudder side of the hinge

The 3rd hinge set will be the lower pivot point that will sit in the fuselage.

More to come - albeit slowly

Martyn

[Colin Leighfield]

Doesn’t seem slow to me Martyn!

[Martyn K]

I am enjoying doing these fiddly bits. Probably a bit pointless as it will never be a class a scale model but these little touches will hopefully add a little je ne sais quoit. If that is spelt correctly 😂

[Colin Leighfield]

Almost! (You don’t need the “t” unless you fancy a game on deck).  I’m currently suffering “stringer blindness”, but most of them are done now.

 

Edited By Colin Leighfield on 04/12/2018 22:46:23

Edited By Colin Leighfield on 04/12/2018 22:47:37

[Martyn K]

Wait til you start the cap strips Colin... You'll be needing a labrador

[Colin Leighfield]

Oh dear, can’t I just use some thicker ribs instead?

[Martyn K]

I have put the tail surfaces away. It all nearly fits but the hinge shrouds are a bit of a so and so to fit... Later

Made a start on the fuselage

Just like everyone else, I made two sides, one on top of the other.

All quite straightforward. The sides are separated by a layer of cling film

While that was drying, I started on the Firewall.

I am going to cut a big hole in the top to allow cooling air to flow through and probably out through the cockpit. As this is a big lump of motor, I have added another 3mm ply layer as reinforcement

Cut the additional slots out on the scroll saw. It really needs finer blades to get in all the fiddly bit.

When dry, I started to mark out the firewall for the inbuilt radial engine mount.

The prop shaft axis was carefully marked ( no side or down thank heavens) on the firewall and checked and double checked then left overnight and checked again..

I finally committed and drilled it.

So - although I dont have any pics the firewall and two front formers have been fitted.

However, I have run into a small problem.

How do you fit the very last former (that holds the skid)? The longerons are extended behind this point and taper together so the former cannot be slid over the longerons. I guess that you have to break the join with the last upright but before I butcher my carefully assembled fur can someone confirm that please?

Thanks

More to come

Martyn

[Danny Fenton]

Hi Martyn, it ha sbeen discussed several times, even made it into RCM&E last time. The bulkhead has to be slid over with the blocks.

Cheers

Danny

[Colin Leighfield]

Martyn, it might make your eyes water to think about it, but I found that there was enough spring in the wood to pinch it in with fingers and slide through without it breaking. My heart was in my mouth but I got away with it. I had been thinking about cutting in three and gluing it in that way!

[Martyn K]

Thanks both

Danny, I have tried that and failed However my longeron extensions look a little longer than yours, but I am sure that mine were cut to plan,

I'll try 'springing it Colin but I have used rather firm wood. They didn't seem too compliant when I tried easing it over

Martyn