Scale Soaring UK

Since I injured my throwing arm some time back, my priorities have shifted to building lighter models, hence the spate of recent 5th scalies...
The recent Minimoa at 1/4 scale proved that it's possible to build a reasonably-sized model and still have a light wing loading, so my current goal is to build the Steinadler at 1/4 scale and keep her under the magic 7Kg's...
I still have the much larger version I built many years ago, but there's little chance I can self-launch her now!

The fuselage is built the old fashioned way: in two halves. This is quicker and simpler than a jig-based assembly, but you have to take steps to keep the fuselage straight...

Good luck with the build Chris.

Thank you, Martin...

Once enough of the 1.5mm planking at the front has been added to stiffen up the front of the fuselage, and the diagonals at the rear fitted for the same purpose, the half-shell can be removed from the board and the formers for the other side fitted...

chris williams wrote: ↑09 May 2019, 11:46 Since I injured my throwing arm some time back, my priorities have shifted to building lighter models, hence the spate of recent 5th scalies...
The recent Minimoa at 1/4 scale proved that it's possible to build a reasonably-sized model and still have a light wing loading, so my current goal is to build the Steinadler at 1/4 scale and keep her under the magic 7Kg's...
I still have the much larger version I built many years ago, but there's little chance I can self-launch her now!

Hello Chris,

Have you never try to launch her with a bungee. It is also more safely safe and no injury for yourself
Pat'

patte de loup wrote: ↑10 May 2019, 11:38

chris williams wrote: ↑09 May 2019, 11:46 Since I injured my throwing arm some time back, my priorities have shifted to building lighter models, hence the spate of recent 5th scalies...
The recent Minimoa at 1/4 scale proved that it's possible to build a reasonably-sized model and still have a light wing loading, so my current goal is to build the Steinadler at 1/4 scale and keep her under the magic 7Kg's...
I still have the much larger version I built many years ago, but there's little chance I can self-launch her now!

Hello Chris,

Have you never try to launch her with a bungee. It is also more safely safe and no injury for yourself
Pat'

Patrick,
Do you know what sort of Bungee we would need for this?? Models are 10-12Kg



BC

It would not be appropriate for our models, Pat, because we are using flat wing joiners. The acceleration would cause the wings to pull back under the ensuing forces. All is not lost: I still have the services of 'Iron'Man' Motley

The small ply plates act as an interface between the 1.5mm ply planking at the front and the 0.8mm ply sheeting at the rear. The cross bracing at the rear of the fuselage is completed, and a card template used to make up the ply top decking....

The ply sheeting is wetted up, taped into a curve, and then forced-dried with a domestic iron. Once glued to the fuselage, masking tape plays a big part in holding it in place. Polyester filler can them be used to smooth out the contours...

Attention now moves to the tailplane...as it tapers in thickness underneath, the frame is built upside down...

The elevator is slightly over-size in relation to the tailplane: this allows it to be sanded flush once the hingeing process is set up. Then the elevator LE can be rounded off and fit finally fettled.
With the tailplane complete, the elevator pushrod can now be set up, once the elevator servo has been fitted in the fuselage...

Now the top half of the rear of the fuz can be closed off as construction of the fin commences...

Tailplane seat now ready for tidying up, fin/rudder ready for fitting, and rudder cable guide tubes ready to install...

Quite a complicated fin fairing on the Steinadler, but a bit of perseverance will see it through...

Looking good chris.

Thanks, Roo... Time now to start on the wings. As there is to be no join at the gull break, the wing is build directly over 6mm balsa jigs. The spars are 5mm sq and steamed to ease the bend... The wing joiners are to be of the 15mm Aeronaut type. The ribs are at right angles to each panel...

Did you spill your coffee over it????

Any pics from yesterday???

BC

No, but I've spilt blood, which is of much greater significance...

With the wing removed from the board, the remaining ply webs can be glued in place, and the wing joiner box epoxied between the spars...

With the wing joiner boxes fitted in the wings, a template is used to position the brass joiner boxes in the fuselage.

The lower wing sheeting can be fitted in one piece, but the gull angle is too severe to do the same with the top sheeting, therefore the gull break is sheeted separately... This makes an initial rig possible to check for dihedral angles etc

Having retro-fitted the sub spars behind the ply webbing, the wing can be jigged up and sheeted, thus locking it into it's final shape...

Time for some more fitting and sheeting before starting on the ailerons

The trickiest part of the job is fitting the wings to the fuselage. Not only do they have to align with each other, they have to align to the fin and be set to the correct decalage. This time around the fairings are constructed separately...

Time now to take a look at the canopies...the side rails are made from laminations of two 3 x6mm spruce strip, clamped to the side of the fuselage to take up the correct curve. The frames are are made from 4 laminations of 0.8mm ply bent around a balsa former...
Although all the existing Steinadlers have flat canopies to the rear of the front frame, the 3-view shows that the original had canopies that were curved. The Skylark 4 (what else!) and the Flamingo canopies were photographed, bought up in Illustrator, traced, enlarged to 1'4 scale and dropped over the plan drawing to show that they would prove to be a very convincing fit...

Construction of the front canopy frame and trial fit of the Skylark canopy...

Finishing off the rear canopy...

View of the rear rib reinforcements, fitting the aileron servo, and finishing off the wing root fairings....

Sorting out the final details before covering & finish...The fuselage has been covered with Solartex and 2-pack primer brushed over the joins and bare areas. After coarse flatting, it will then be sprayed with 2/pack primer, flatted again with 600 and then the top coats applied.

The Steinadler is now mission-ready (I hope)... The flying surfaces are covered with the new HK matt clear film + trim

AUW Just under 7Kgs

Well done Chris, very nice colour scheme,
Should look great in the air,

Very pretty Chris! I must build something with see-through wings at some point.
Will it maiden at MW this weekend?
Brian.

I'd like to, but poor old Geoff's away for a week, and he'd hate to miss it

Still no maiden, but time for some formal pics last evening...

Very pretty! Shame tomorrow’s W.S. Scale Day is off.

Nice,very very nice.

It took all day, but I finally plucked up the courage to maiden the Steinadler at White Sheet this afternoon...Well chuffed!

You're not going to bother covering it then.......................?

(Seriously, very nice, just need to sped up a bit and you'll have it cracked )

Hello Chris,

According to which plan have you built this beautiful model. I'm always looking for a blueprint on a scale of 1: 4 but have not found so far. Either too big (Schneider Modellbau 1: 2,25) or too small, span only 3,50 meters.
Greeting Eddi

It is built from my own drawings Eddi... I have not made a formal plan, but I can make the working drawings available to those who want them

Hallo Chris,

Oh yes, that would be very good.
Please let me know how we handle this. You can send me an email to bastelfuzzy@web.de

Greeting Eddi

Things are a bit busy at the mo', but I will tidy up the drawings when I can & let you know...

Just luv the Steinadler...

Also, for those who enjoy Scroll Saw Therapy, the parts are available from me in PDF form, all ready to print out in an A4 printer. (Note: always check the printout outs against the plan)

Hi Chris,
I have the blueprint of the golden eagle Musger 19a from you. Unfortunately there is no indication of the center of gravity on the construction plan. Can you tell me where the point of gravity is.
Greetings Eddi

Here you go, Eddi...

hi chris,
many, many thanks.

Greetings Eddi

Video here: