Sopwith Dove for CO2

[Squirrelnet]

Now the cabane and undercarriage mountings have been done the side cheeks can be added with some light 3/32" stringers and 1/32" sheet . Taped and clamped while the glue dries

[OZPAF]

The flex mounting of the cabane struts is interesting Chris. Does this system rely on the rigging to keep the top wing accurately in position?

John

[Squirrelnet]

Hi John

 Yes indeed the rigging will dictate the exact position of the centre section, though I must say the system has a far bit of rigidity to it already more than I expected . This also means the model will be one piece

[Squirrelnet]

More undercarriage today with the spreader bar and wheels

I'm trying to keep the weight down so was reluctant to add a heavy wire spreader bar along with a wire axle which I'll need for springing. The plan is to use a wire axle attached only at the centre so the flex provides some springing in the same way as the original with it's centre split axle and bungee cord suspension.

The idea is to use some 3mm carbon tube which is located by thinner wire fittings solder to the UC legs. the fittings extend 3/8" into the spreader so no need to glue them in and like the wings the thread rigging will hold it together

Wheels are the same construction I've used before. A balsa core of two laminations of in this case 3/32" with Proskin Cyano'd on to make a composite structure. The tyres will be 6mm neoprene cord but I haven't got any in that size so just ordered some from ebay . The hubs will be birch dowel but that's a job for tomorrow


 Note as well I've cut a V section in the firewall in a similar manner to the original but in this case to provide some warming air to the bottom of the CO2 tank

[OZPAF]

Thanks Chris. I'm thinking of using a similar approach for sections of undercarriage not taking any loads.

John

[Squirrelnet]

Moved onto the tail skid this afternoon which is from some spruce hardwood. It locates at the front in a 3/32 sheet former while the centre attachment is from 1mm carbon rod with some balsa dowel centre drilled to give some extra diameter. The carbon rod extends up into the tail post . I noticed as well that the tail fin post is separate from the fuselage so I've modified the rear of the fusleage accordingly

[Squirrelnet]

The wheels have had their hubs made up too from some 3/16" birch dowel . the wheel s were drilled to take the dowel which extends into the space behind the wheel cone and small gussets added for strength

 

[Squirrelnet]

Spent some time this afternoon sorting out the wings. I've decided to go for 2 spars of 1/8" sq with the front one in spruce. The LE is 1/4 balsa dowel and TE is flat 1/16 x 1/2" . After about hour or so therapeutic cutting out round a ply template I have a rib set of 40 ribs which is enough for the wings, I'll sort the centre section later. The ribs are mostly 1/32 with the root ribs 1/16 for the top and 1/8 for the lower wings


The tips are drying after forming 3 x 1/32 laminations around some card formers. I had almost run out of 1/32 Basswood sheet but I note Hobbycraft have 1/32 x 24" x4" sheets back in stock so got a couple of those which should last a while 

[OZPAF]

Hey - that's a bit much - using the lathe to centre drill the wheels 

Very nice build, Chris.

John

[Squirrelnet]

Hey - that's a bit much - using the lathe to centre drill the wheels

...well I have justify it's existence  and means if nothing else the hole's in the middle..at least until the first heavy landing

Wings today - I have the bottom wings basic assembly done with the 3x 3/32 basswood laminated tips fitted

[Squirrelnet]

Top wings this afternoon. Quite quick to do as I'd already cut out the ribs set. I did the centre section too .The top wing will be one piece so I'll join it altogether tomorrow with 1/32" ply dihedral braces.

Dihedral is 3 deg which rather luckily at this scale works out at 1/2" at the tips so that should make it easy tomorrow


...couldn't resist a quick lash up as well

[Squirrelnet]

The top wing is one piece so will dihedral braces from 1/32" ply as the wings also sweep back I've added a small wedge shape to the spars so the the plate can fitted to flat to the spars. Dihedral was set to 3 degs but looking at it didn't really look enough particularly when looking at flying shots of Mike Smith's FF IC powered version so I increased it from 1/2" at the tips to 3/4". Not very scientific but it looks better for a FF model

For the centre section I'll get the fit and mounting right but  may cover and paint the fuselage before I actually glue it on , similarly with the lower wing


I look at the interplane struts next which given it's a one piece model will be simple sockets to glue the struts into .

[dputt7]

Really nice Chris, well worth the effort

[OZPAF]

What a neat looking little biplane Chris.

John

[gravitywell]

Your building skills are so far ahead of mine, you make mine look like they are banged together with rocks!  Beautiful work.