1/5.5 Dornier Do335

[Phil Clark]

Nose wheel steering servo & nose door air rams installed..............

[Phil Clark]

Space up front is tight for the 3W 85's muffler system......a Zimmerman canister is being used internally, but no suitable manifold exists to fit the space available, so manufacturing from scratch is the only option. First a 3mm st/st flange was hand cut then using a KS 28mm dia manifold kit, after much tried and error, the manifold is taking shape (Thanks must go to Harry Harland for this work as he's working with me 1 day a week and this metalwork is all down to him.......lovely job Harry)

[Phil Clark]

Forward fuselage cannon troughs complete......

[Phil Clark]

As this is being converted to the 2 seater, the 2nd canopy isn't included in the kit. A plug has been fabricated with balsa/ply formers matching the cockpit opening (combined with the Arthur Bentley drawings) + high density PU foam. This will be glassed (several times) finished to a high gloss finish before a female mould is taken and a temperature resistant PU resin vac-form plug is poured.

Here's the plug after it's 1st later of glass.

[Phil Clark]

Back to the front muffler......................this has taken a lot of thinking about & plenty of test fitting & adjusting before it all fits in the space available.

With the inverted engine with a side exhaust, the manifold is running pretty tight up against the port side of the fuz. The 85cc Zimmerman canister we're fitting cannot run straight back from the header as it'll be touching the side of the fuz plus is too long to fit in front of the next former back in the fuz.

The next idea was to fabricate a shallow swan neck type header to allow the canister to be mounted centrally inside the fuz; problem now is that to get it far enough behind the rear mounted carb, this not only makes the header too long than the recommended 7", but it also means the back end of the canister encroaches into the front cockpit.

3rd option is to mount the canister diagonally from port to st/bd.......this allows it to fit in front of the front cockpit whilst achieving the correct length headed and leaving plenty of clearance around the carb for choke & throttle servos.

The header made up last week is extended a couple of inches to the rear with a straight length of 28mm st/st tube swaged at the end to allow it to slide over the piece it's connecting to. The 'kink' was then made up and silver soldered to the inlet of the canister.....this allows the Teflon joiner to run fore/aft rather than diagonally making it easier to push fit together as the canister is fitted through the nose gear opening, but the headed has to be pushed on through the opening in the firewall.

[Phil Clark]

Looking up through the nose wheel opening, here's the rear end of the canister with it's fixing clamp clearly showing it's diagonal position. The ply plate straddling the fuz for it's fixing is yet to be bonded in. The twin exit pipes are trimmed flush with the underside skin and exit a little off centre 3-4" behind the cylinder head.

[Phil Clark]

Much progress on the335 over the past month............

Rear canopy tooling complete. Basic plug finished as per any glass skinned surface. Final surface finish is Klass Kote epoxy flatted to 1200 then polished. A 2 part epoxy glass mould is then taken before this is used to pour a temperature resistant aluminium powder filled PU resin vacform tool. A foam insert is supported inside the tool to give 1/2 - 3/4" of resin.......this not only saved resin, but it prevents excess heat build up in the tool as the PU resin cures.

[Phil Clark]

Throttle & choke servos for both engines are fitted with linkages ready to be finally connected. (Sorry, no photos of the front installation as it's almost impossible to photograph them buried in the nose).

[Phil Clark]

The person who had started building this before we were asked to finish it unfortunately rubbed the whole fuselage down with quite a coarse wet and dry. This removed much of the raised surface detail and what was left was far from crisp & defined, so using the 'body filler against PVC tape method, all raised panel edges have been re-applied. A lengthy task, but we're now pretty much done & the fuselage & wings are now awaiting final surface detailing.

[Phil Clark]

The fuselage then receive 1 coat of 1K etch primer followed by grey cellulose. This shows up all remaining imperfections which are sorted with 3M red stopper, further wet sanding & primer.

[Phil Clark]

Inner gear doors as per the mains are very thin & flexible as supplied. These are stiffened internally with 2 layers of 390g twill weave cloth & peel ply before taping in place over the wing/fuz to ensure they cure to the correct curvature. Area covered in brown parcel tape to prevent everything sticking.

Once trimmed, they are hinged with Sierra's aluminium off-set door hinges. The non-scale wheel well liners preclude installation of a scale mechanical inner door actuation system, so traditional air rams are being used.......1" travel x 1/2" dia HAWE rams being mounted on a pivoting mount that wraps around the central fuselage wing joiner phenolic outer socket.

[Phil Clark]

4 x 22 cu.i metal air tanks installed...............

[Phil Clark]

No space to fit regular Dubro tanks, so custom sized conformal tanks are being moulded using the lost foam technique. Approx 30oz for the rear engine, 40oz for the front.

[Phil Clark]

Tanks done ready for mounting...............

[Phil Clark]

Three functional hatches have been added in the fuselage to gain access to the front & rear carb needles, plus the bolts for the rear manifold (which can only be fitted once the rear engine in in place). These are laminated litho & Proskin with TamJet off-set hinges. They are held shut with scrap magnets from old brushless motors.

[Phil Clark]

Silver soldered piano wire/sheet plate upper & lower rudder closed loop torque rods fitted...............upper & lower hatches added to gain access to connections.

[Phil Clark]

Rear canopy arrived and trimmed to approx. shape...... + starting to add some detail to the fuselage in the form of resin cast hatch latches along the edges of the hinged 'scale' engine covers

[Phil Clark]

......and the fun & games of flush riveting the flying surfaces has started......stabs complete, well on the way with the wings now.

[Phil Clark]

It's been a while since the last update, in the mean time, we're 99% complete with the basic construction & systems install (apart from Rx's, retract valves, plumbing & wiring).......so we're on with the detailing now................

Front & rear dummy exhaust stacks..........fairings & shrouds from styrene, exhaust are individual resin castings.

[Phil Clark]

Patterns & vac-formings for the front & rear cockpit seats.