Large Model Association Forum

BACKGROUND

Whilst in hospital, having a gangrenous little piggy sent to market, my wife made the schoolgirl error of leaving me her i-pad to help me pass the time.

I spent the time trawling through aviation and model related sites and came across the BU180. Having always liked this aircraft, a further search found that Fighter Aces could provide a 3 sheet plan for the Jerry Bates 1/4 scale version.

After being paroled from hospital and facing three months with my foot elevated (my missus had changed the padlock on my workshop to stop me going in whilst I was supposed to be recuperating and she was at work - she knows me too well) it was time to re-visit the BU180. While on line there was a knock at the door and Padraig Post handed me a large postage tube from Fighter Aces containing....yep you guessed it...a set of BU180 plans. Spooky or what?

At this point I would like to issue a PUBLIC SERVICE WARNING! Do not have internet access and a credit card while on weapons grade pain relief

Apparently I ordered the plans whilst in the arms of Morpheus and have no recollection of doing so. Just as well the post arrived when it did as I was in the process of ordering a second set of plans!

Having spent the 3 months of relative immobility studying the plans it was back to work. With retirement looming I decided to treat myself to a new, larger workshop, so empty the old workshop (how can so much stuff fit into an 8x10 shed?) dismantle and remove the old workshop, prep the ground and then erect a shiny new 12 1/2x12 1/2 workshop. it then had to be insulated, painted and workbenches made before everything could be put back. About six months in total and one very understanding wife. as I stored the contents of the workshop in the living room.

I had worked out the cost of materials and would have been hard pushed to meet the cost of the Belair semi kit, plus all the time and effort to trace and cut the components would have turned this into a five year build (or an abandoned, part built hangar queen. Admit it, we've all been there. ) It was now time to give up honest graft and become a full time pensioner and as a parting gift my colleagues got me the semi kit I had enthusiastically been bending their ear about for the previous few months (probably to keep me occupied and not turning up to bore the ar*e off them with how great retirement was. )

The kit is beautifully laser cut and can, in the main, be dry fitted before throwing some Zap at it.

As I have been banned from boring the ar*e off my ex-colleagues, I've decided to bore the ar*e off you lot instead so here goes...

Hi Dougie---good to see you on here--and looking forward to seeing your build,especially the finishing which I know you will make a fantastic job of after the cracking job you did with my[Peters ]B17----

Thanks for your kind words Dave, I'll try and keep it light hearted and hopefully throw some humor into the mix.

Please don't take this as a "how to" rather a "how I did it" and I would welcome any feedback on what I'm doing and am always open to suggestions as I am convinced there are better ways of doing a lot of the techniques I use.

As I said, the Belair kit was beautifully laser cut and fantastic value for money, however the center cores for the elevators and rudder were M.I.A. An e-mail and a couple of phone calls to Leon at Belair to identify the exact parts missing and the missing parts were with me in less than a week. No muss, no fuss, fantastic customer service. Well done Belair! I will be using you again.

Scale detailing being a great source of enjoyment, although nowhere near competition standard, I just like to do it for my own satisfaction. I therefore decided to start with the instrument panels, just to break myself in and get back into building again after a couple of lazy years of foamies.

I used the Graupner vintage instrument set consisting of plastic bezels and sticky back instruments. Being Graupner, the instruments were printed in German - result! This saved me my usual route of sourcing photos of the correct instruments on line, sizing them and printing them on photo quality paper.


I didn't fancy just sticking the instrument to the bezel as this looks fake and too toy like to my eyes, so I drilled and sanded out the part the instrument dial stuck to, leaving just the bezel. This was then attached to the laser cut panel and the whole lot sprayed black.


Several coats were given to hide the grain and a sheet of white plasticard was placed behind the panel during one of the coats so the over spray would show the exact position of the individual instrument dials. A search for the BU180 on-line provided some excellent information, including instrument placement. Each instrument was then carefully placed in the correct position , aligned and stuck down.


The magneto switches were fabricated from thin aluminium to the correct outline,

and placed in position with small washers as the surrounding switch bezel before a final coat of black.

The final stage of detailing was to create the information labels and makers plate on the PC and printed on waterslide paper.
The wording on the information labels is correct (in German ) even though it's too small to read, even with a magnifying glass, but I know it's there!

The plasticard was then overlayed with clear acetate and then the panel. I used strategically placed spots of Copydex to stick it all together so that there was no chance of fogging the acetate.

The finished item I think looks ok with some 3D depth. A lot better than instrument dials just "stuck on"!
DJ once told me, "you can't see the fine detail when it's flying past at 100 feet." True.... but I know it's there!

I ordered strip wood and balsa sheet from SLEC, some hardware and adhesives from Nexus and pilot figures from Aces of Iron in Trumpton

I needed a Japanese pilot for a Byron A6M zero I picked up at a bargain price which needs some refurb', an occupant for the rear of the BU 180 and a replacement for my other current project, a Genesis that I,m doing as sort of golden era-ish.

I had previously bought a 1/4 scale figure for the Genesis but it just looked far too small for that model so it's the front cockpit of the BU 180 for him.
As you can see. there's a fair difference between 1/3 & 1/4 scale.

The rear cockpit will be occupied by the second version of the golden era pilot, collar open, goggles up.

There is nothing worse, in my opinion, than identical figures in the same model. If you have no choice, try and paint different expressions on their faces. If you have seen Dave Johnston's (Peter McKenna,s ) Sally B, B17, that's some of my work. Three identical figures, the difference is in the paint work.

I must have painted about thirty of these figures for my self and others by now and find the detailing is excellent and even with import duty, good value for money. If you go to the website at http://www.acesofiron.com and follow the painting guide, it's almost impossible to do a bad job.

You need enamel, acrylic and oil paints which can be sourced very cheaply. I got a set of 12 oil paints for £1 at one of the pound shops and they stock them on a regular basis. Not the quality of Windsor & Newton but more than adequate for our purpose. I also downloaded and printed off several versions of colour wheels so I can mix any shade I wish.

You won't finish one in an evening but I paint a bit of the figure whilst waiting on glue/paint drying on the build. I find that by the time the model is ready for occupancy, so is the figure.


If you want, i'll include the occasional picture of the painting progress in this thread as I go. Let me know.

Next up was some metal bashing to fabricate the undercarriage. First up, the tailwheel.

This was fabricated from K&B brass sheet, piano wire and plastic tube.
The piano wire was clamped in a vise and heated to a cherry red to make it more maleable then bent to the correct angle using percussive persuasion (a hammer ) to get the correct angle. I find that pulling on the wire by hand gives a gentle radius, using a hammer gives a tighter radius.
The wire was offered up to the plan to check the profile and adjusted until the correct profile was achieved. Once happy, it was reheated and immediately plunged into cold water to re-harden.
The bracket was traced onto grease proof paper, stuck to the brass plate, cut out and bent to the correct profile.
The parts were joined with silver solder and the plastic pipe was drilled to the correct i/d to slip over the piano wire.
A commercial 1 1/4" tailwheel and control horn and the jobs a good ' un.
A very satisfying afternoons work. As you will probably have worked out by now, I am not the worlds fastest builder, but I've paid the money and intend to savour every moment.


I followed the same process for the main U/C but left joining the mains to the trailing arms until I had the U/C mounting blocks in place to use as a jig.

I decided to start the wood butchery (prophetic term ) with the horizontal stabilizer. This went together beautifully and was looking good until I set about the final sanding with a palm sander (converts wood to dust) .

Now, power tools have a place in aeromodelling, that place is just not in my hands! . So it was back to old school and trace, cut and sand a new set of tail ribs.


and start again....

This process reinforced my decision to go with Belair however this time all went well.

The plan showed a type of hinge (American) that I'd never seen before and a web search came up blank. Even the company didn't appear any where.

So it was out with the paxolin board and make hinge points for the torque rods.



And the finished stabiliser ready for a final HAND sanding!


In retrospect, I should have affixed the torque rods to the elevators first and then fixed the completed elevators to the stabilisers

My original intention was to do a build thread on my club web site, however this is being re-done at the moment so I thought I'd do it here instead, however, as a result the build is a bit ahead of this thread and I'm currently working on the fuz. The plan shows the use of a bellcrank on the rudder pull pull system. My concern is that even with a bush fitted, slop may develop if the support shaft develops wear where it is attached to the servo tray and its position is in an area where maintenance would be impossible without major surgery. Would fitting the pull pull wires directly to the servo arms be an acceptable alternative?

I've used both methods successfully in the past but never a direct pull pull to servo on a larger model.

With the exception of the throttle, I'm using Hi-tech HS5645 MG ultra torque servos throughout.
I would appreciate your thoughts.

Too late now Doug, but it seems that the CB Associates hinge range are available from ScaleAero in the USA:

https://www.scaleaero.com/cbhinges.htm

Thanks for that Alan, I,ll file that for future reference

Doug

Close loop direct to the servo is the way to go. Just make sure the geometery of the arm on the servo and the rudder are the same to avoid binding or slop in the cables as the servo moves.

John

Thanks for that John, the servo is programmable so I can set everything up exactly as I need to prevent bind or slop.

Next up is the bi-lateral levitation devices (wings to you and me )

The parts were laid out over the plan to ensure they were all present and correct,

everything was dry fitted, making sure all the jigging tabs were flush with the building board to ensure a warp free wing with the correct washout achieved and the root rib had the correct dihedral angle. Once happy, everything was glued up and the phenolic tube for the wing brace was added.

The sheeting was added using the masking tape and glue method to create panels to cover the wing. I used aliphatic resin to secure the panels to the ribs to give some working time and weighted down until the glue had cured.
Wingtips added and a final sand to the correct profile and repeat the whole process for the other wing.


I have left the creation of the servo bays until the ailerons are built so that everything lines up properly.

Random thought for the day: oxygen is like sex...you never miss it until you are not getting any.

Dougie Sheppard wrote:Thanks for that John, the servo is programmable so I can set everything up exactly as I need to prevent bind or slop.

Doug
A programmable servo will not help with binding or slop. It is important that the geometry of the horns is correct. The easiest way to do this is make a copy of the rudder horn and mount it on the servo disk.

AEB

Thanks John, will do

Brilliant start to the story! Those drugs make us do crazy things!

Scary thing Robert, is I genuinely have no recollection of ordering the plans whilst in hospital . Likewise family and friends visiting. I had to apologise for anything I may have said while off my head on "class A".

Apparently I was quite entertaining.

The ailerons, like all the control surfaces, are constructed around a ply core with a solid balsa L/E and ribs.

The control horn was modified to give a more scale profile.

The trim tabs were made from litho' as per the plan. It's not the clearest of photo's but hopefully it will give you some idea of what they look like.

Because I didn't have any CB Associates hinges, as specified in the plan, I modified Robart hinges to suit

and fitted balsa blocks to give them something to bite into.

The full size had fabric covered control surfaces and this is replicated in the model.
I normally use solartex for fabric covering but I would like to try doped nylon for a change (I have seen some beautiful results using these materials. ) as part of the wings and fuz are fabric covered, so I am going to make some highly crafted (knock up ) some panels to practice on.

I'm sure some of you have had some experience of using this method/material in the past, or even be using it at this very moment and I would appreciate any tips or guidance you may wish to share.

The posts have now caught up with the build so will become a little further apart but watch this space.

Dougie

Rather than doped nylon I suggest you use Diatex, available from Skycraft Ltd, Spalding. We use Diatex 1000 on all our fabric covered models. It is a heat shrink fabric that we attach to the structure with a heat activatable glue (Balsloc or similar). Once covered and tightened with gentle heat the Diatex is then doped to seal. Full details of how to apply it have appeared on this forum many times in the past.

John

Thanks John, what an intriguing web site, I'll spend a couple of evenings scrutinising it, lots of interesting and shiny stuff. Don't know what half of its for, but I want it.

What weight of cloth would you recommend? My original plan was to use nylon with pond sealer over the sheeted areas and dope over the open areas and control surfaces.

Will this method work with Diatex as well?

No rush, I'm still a fair bit away from the covering stage but I like to have everything to hand so any delays are down to me and not waiting on deliveries.

Dougie

Diatex 1000 is what you need. As stated in my previous post I use heat active glue to apply it as it is much easier than using the "cement" they recommend. On my vintage gliders I use Epifanes varnish on the sheeted (ply) parts and doped Diatex on the open structures but if the sheeting is balsa you will be better covering the whole thing with Diatex as the balsa will be very prone to hanger rash.

AEB

John,

Thanks for that, that's the route I'll take.

Dougie