WWI Stringbag Build

[Paul]

Or a basic "how I build the things"

Paint the internal parts of the cockpit area. With most kits this is difficult to see when the plane is finished so I use dark brown, unless the cockpit has detail..like for example in the Roden kits.
Check for fit and then Glue the two halves of the fusealage together.
I add the engine cowling at this stage. Paint any engine parts that will later be inacessable, these will become apparent when you prefit the cowling.
I know that the prop can be added so that it spins (held behind the cowling by a little plastic cap) but to be honest, IMHO, that´s a pointless excercise. The thing aint going to fly so the prop doesn´t have to spin
Also if it´s added now it´s just one part that gets in the way later in the build. I advise adding it near the end of the build.
When glued, fill any gaps (liquifeid sprue is good for this) and file/cut down any excess parts of sprue you may have missed.

Work out a rigging plan. This one´s quite a simple rig but every type of plane needs a slightly different plan /order in which the rigging is carried out. Don´t go mad and try out a complex rig right at the start..it will only put you off.

A couple of Stringbags that are "easy" to rig;
Sopwith (camel and pup)
Albatross DIII
Fokker E.III
Siemens Schuckert DIII
Spad XIII

Drill the holes for the rigging. At this point the bottom wing isn´t attached but just held in place to work out at which point the rigging holes nearest to the wing stub will go. These need to be as small as possible and equally spaced. Note: on this plane I´ll be added the aileron lines and these have to be lined up on top and bottom wings.

Glue the bottom wing to the fusealage...leave off the the tailplane..it is another part that gets in the way at this point.
(next stages later)

[Peter]

Very interesting tutorial Paul

I keep an eye on it

[Paul]

next bit.
The wingstruts. With this kit the rigging is easy. Some stretched sprue simply glued to the "frames"
With the single strut kits..the ones where attaching the top wing is similar to balancing jelly on a wet balloon, I use the the predrilled rigging holes to attach the cross wires.

Paint and decorate the fusealage. At this stage I paint the top of the bottom wing and the bottom of the top wing. When everything is dry, check all the rigging holes, clearing any paint that has blocked them up.
The decals. They are removed from the sheet in the usual way but..I smear the area where they will be placed with some woodglue that has been thinned down with water. This allows the decals to firstly sit in a film of liquid and give an opportunity for slight adjustment. When they are where they are supposed to go, I gently press them down with a toothpick, squeezing any excess glue from under the decal and remove it with a small piece of tissue. If there is any shine left around the decals from the glue..just paint over it.

The propeller. Basically, paint the whole thing mid brown. Then add very thin lines of very light sand brown, then with dark brown clean up the sides of the light brown lines..(best done when the paint is still wet) and when dry, add a final layer of Darkbrown textil paint. This is used for painting T-shirts etc. It´s acrylic based, is semi translucent (doesn´t hide all the details underneath) and gives a mid gloss effect when dry.

[Paul]

The tricky bit..the wings.
The struts are added to the bottom wing. Use the top wing to align them and to control wether they are lined up with the slots in the top wing. This doesn´t have to be 100% but as near as possible.

Allow the struts to dry for about half an hour so that they start to bond but aren´t totally fixed (they still ahve a bit of movement)
The unpainted areas of the struts can be painted.
Put a small amout of glue in the slots on the top wing.
Holding the plane by the tail with the front pointing away from you, tip the top wing so that the front edges is facing down and slowly tip it onto to struts bringing the back of the top wing into position last. ( I would have taken a picture of this but I didn´t have any hands free)
Attempt to get the outer struts into position at this point. Still holding the plane by the tail, use a pair of tweezers to locate any any struts that are not in place into their slots. The top wing may start "sliding" about (the jelly on a wet balloon effect, worse with wing struts that are attached individually, like on the De Havilland D.H.2 kit) but with a bit of patience it will suddenly all fit into place.
Using the tweezers as mini pliers, squash the tops of the struts into their slots. Check for alignment, the front edge of the wing being in parallel with the bottom wings front edge, that the ends of the wings have a equal amount of overhang at each side (if the outer struts are at 90 dgrees to the wings then they should be square) If not, then gently push the wings into position.
When everything is ok, lay the plane on it´s back and wait a couple of hours.

I´ve already added some "invisble" thread to the fusealage and look at that horrible mold mark next to the wing struts on the right!!!!!! .

[Paul]

The really annoying and fiddly phase..the rigging.
Preperation, tweezers and at least 8 small postage stamp sized pieces of selloptape (or other tape) attached to a convenient surface where they can be easily got to, the edge of a table top for example.

I use "invisible" mending thread for rigging..but wire, stretched sprue, thread etc can be used.
I´ve found it best to start from the middle (nearest the fusealage) and work outwards towards the wing tips.

My Sequence is ;
1. Take a length of thread..make sure it´s at least 10 cm´s longer than the span needed.
2. From the above of the top wing (plane sitting the right way around) put the thread through one of the holes.
3. Using tweezers, catch the end of the thread from the underside of the wing and take it to the hole in the bottom wing and push it through.
4. Pull a length of the thread through (about 5 cm´s)
5. Attach the loose end of the thread to the wingtip using sellotape (any tape will do)
6 .Take the free end of the thread and put it through the hole on the opposite wing to the one that now has the thread taped down.
7. The same as number 3
8. This time, wrap the thread around (or grip it tight) in the finger next to your pointy finger.
9. Grip the tip of the wing with thumb and forefinger of same hand and using them to hold the wing in one place, pull the thread tight by moving the finger with the thread wrapped around it away from the wing.
10. When the thread is tight...(look along the length of the line on both wings) stick it in place with another piece of sellotape.
11. Repeat 1-10 three more times

At no point cut off any free lengths of thread..no matter how much they get in the way of the rigging process. They may still be needed to pull one or two of the lines tight. They can go slack as other lines are added and the wings "solidify" and shift slightly..the plane takes on a natural tension within the wing structure.
If your getting confused as to which line is done and which not..colour the extra bits of thread from the finished lines with a red marker pen. Or just do what I do...get frustrated and annoyed..good excuse to have a coffee break though.

Carefully fill all the holes from top and bottom with strong glue..Liquid pattex for example and leave to dry overnight.
I haven´t attached the lines for the ailerons as they would only get in the way at this point.
Now though..it can be seen why I didn´t not paint the upperside of the top wing..and the bottom side of the bottom wing. Firstly the paintwork would get ruined and secondly the sellotape wouldn´t adhere too well


On the top of the wing you can see the threads. IF..the rigging cannot be pulled tight from the wingtips (it´s all too confusing which line is which and you don´t want to start removing bits of tape for fear of making a tight line go slack by mistake) you can push a toothpick (or whatever) under the lines to tighten them. Same for under the fusealage
If..the next morning one or two lines are ever so slightly slack and the glue has dried solid..don´t worry, there´s a trick to tighten them.

More tomorrow

[Peter]

That's a lot of work Paul, but it stays very interesting!

[Paul]

So..next day. The rigging lines are fixed but one was a tiny bit slack. To cure this I used the glowing end of a ciggarette held close to the line. This makes the line shrink a bit and go tight.
The ends have been removed using a razorblade, the excess glue sliced away, wing top and bottom painted and the decals added.
The wheel supports can now be added.


It will be allowed to dry for about an hour then the wheels added.
The kit also didn´t have a landing skid, not attached to the fusealage or anywhere on the sprue. It is an old kit and didn´t come with an instruction sheet so maybe it was broken off. Anyway, a lenth of paper stable and the skid is added.

[Peter]

Excellent final result of the rigging Paul

[Paul]

Thanks..
The string bag is finally finished.
Streched sprue for the rigging lines between the landing gear. I could have gone for the top and bottom airelon lines, the ones on the tail plane etc but I´ll think about that for the next one. I can always add them later



A couple more pics and the Airfix Sopwith camel HERE