Topic: Blackburn B2 build pics!

I had a generous response to my plea for 3-views of the Blackburn B2, so it seems only right to post a few pics of the on-going build! 

Basically, we're looking at a 1:5.5 cartoon scale model, spanning 65" and aiming for an 8lb AUW.  Power will be from a 5S cell pack, a Turnigy 42-60outrunner and 14x8 prop.  This is a known set-up and yields 1100 watts.

A couple of pics of the real thing (based at Old Warden) though.  This aeroplane is nearly 80 years old, and still loops and chandelles its way through its display routine!



A sort of side-by-side Tiger Moth, except that the fuselage was ahead of its time in using an all aluminium stressed skin monocoque.



Here's the SO giving it a sense of scale.......

Using a Denis Bryant 3-view as a main reference, I got the crayons out and drafted out the outlines.



Construction started with the upper and lower wing centre-sections......



.....followed in short order by the outer panels, which plug in using CF dowels.



The tail surfaces are 1/4 strip with 1/8 capstrips to give some presence.



Work on the fuselage started with building a couple of formers onto the lower CS.



It seemed a good idea to push on with the cabane struts before the fuselage sides were added.  So a balsa jig was built on top of the formers and the upper CS tacked into place.



The cabane struts could then be built in situ, using 12swg uprights, 18swg diagonals and brass P-blips, all bound with fuse wire and soft-soldered together.



The jig was then removed......



I made up a balsa frame (painted black for clarity), slipped the wing panels in place and used the frame to hold the panels at the correct sweepback, incidence, dihedral and stagger so I could set about fabricating the interplane struts.



And that is the story so far!

tim

A fair bit of progress there Tim, well done!  I've always liked the B2, as it's an interesting alternative to all those (admittedly still nice!) Tiger Moths......

Will you be offering this drawing for publication in one of the mags Tim?  I may just consider having a go at this one, although I'd want to fit one of those noisy oily things on the front......

Thanks Brian! 

As for publication - well, everything depends on whether it flies or not!

Having said that, these days RCM+E seem willing to publish my doodlings, although I really don't think even they will be able to get the B2 on a freebie format.  Mind you, I said that about the Cygnet.......

Anyway, I managed to finish the interplane struts today, so the next step just has to be the fuselage at long last!

Hi again Tim.

I thought RCM&E did well to get the Cygnet in as a freebie, so perhaps they'll do the same with the B2 if they go with it? I do hope so, as your B2 offering is just about the right size for convenient everyday transportation. Ok, if I wanted to fit say, a Laser .70, I'd have a few mods to do around the nose area, but I don't think it would involve anything too drastic.

Morning Brian, and thanks for the interest!

Converting the B2 to ic power shouldn't really be an issue - the fuselage will be an all-sheet box (with rounded corners) with a substantial 1/4 ply firewall up front.  Should be an easy matter to reposition it as needed to suit a 4-stroke, but I'll leave that to you!

tim

Hi Tim

I've looked at several of your designs in plan form (as opposed to planform), and your construction methods seem quite workable, in that modification looks fairly straightforward. I'll let you know if I should attempt it!

Brian,

If you do decide to have a bash at the B2, you'll find a far more comprehensive build thread on RCM+E own pet forum here;

http://www.modelflying.co.uk/forums/postings.asp?th=56199

Other than that, the fuselage sides sides have made their public debut.....

tim

Superb pictures that's magazine quality with no clutter in the back ground nice build to 

Thanks for the link to the RCM&E site Tim, I'll be looking in regularly.........

Thanks Gents!

More work on the fuselage in that the internal formers and snakes are installed;





This evening I re-pinned the fuselage back on the board, and jigged up F1 on a block of balsa scrap....



....before adding the sides of the cowl.

That's looking great Tim! You don't hang around, do you?  If you need some litho plate for the fuselage, I might know where there's some to be had. 

Gordon

I'd have thought Mick Reeves Metalcoat could be a strong contender here........

Thanks Gents!

I had a look at Reeves Metalcoat, as well as a couple of examples of aluminium foil.  In the end I bought a couple of full sheets of Flair Aluclad (£21), which will be ample for the fuselage, upper CS and fixed fin.

Progress on the B2 continues with the 8mm ply motor mount.....



.....followed by the wet-formed 1/8 balsa shoulder sheeting.  I re-atteached the cabane struts just to make sure that everything is still aligned as it should.  And it is!



Adding the 14x8 prop and spinner also means that I can get to grips with the top decking, followed by the front hatch and nose piece.

The top decking is on, and hacked to the appropriate shape.



The front hatch followed on in turn.  Planked from 1/8 sheet, I also added a few 1/8 BBQ skewers for rigidity.  I may skin the the whole caboodle in 1/64 ply if need be.



Unable to source any little oleo thigies, I set about making my own from brass rod and tube with some tough little spring encased within....



The finished items are 100mm long and will be fitted with balsa fairings.



Now I need to consider how to tackle the UC swing arms!

tim

Still watching with interest Tim. 

I'm sure I spotted some ready made oleo legs like yours on the Huge Haddock site last time I looked. I'm not a regular vistor to the site as GC sell mainly items for electric flight, but they were there I'm sure. They'd need to be the right size of course. Having said that, there's the satisfaction of producing your own of course.......

The last oleos I assembled were in a Precedent Turbulent (1/3rd scale). On final assembly I packed them with Vaseline and it seemed to help them function better.

What a fine job you are making of this Tim.   It's looking great.

Alan

Brian,

I did look on the GC site but couldn't see anything suitable.  Anyway it's much more rewarding to cobble up yer own stuff, isn't it?

Alan, thanks for the compliment!  As ever, the proo of the pudding will be in whether it actually flies or not! 

Anyway, I've been cobbling together the swing arms from 8swg piano wire on an upturned piece of bread board....

A neat and tidy solution indeed Tim. Just one thing though. You may just find you need a little more strength in the u/c joint where the brass "P" clips are. I may be wrong, but I rather fancy that particular joint may need to be bound with wire prior to soldering. Apologies in advance if that's what you were going to do!

I like the jig. Looks like you're very much into "home brewed" solutions Tim, and that's the sort of modelling I like! 

P.S. I don't think you need have any worries about the model flying ok Tim, you've used a known wing section and you've got the rigging angles as near as you can. It'll be fine, you'll see.

Hi Brian,

I did consider using fuse wire - honest!  In the end I figured that filing the piano wire to a rough finish, hammering the brass to make a tight fit all the way around, flooding with solder, then drilling and bolting the free ends of the clip together might just suffice.  We'll see how it goes!

Anyway, it all seems to fit on the model as it should.  I'm using Robart 3 1/2" wheels, by the way.

tim

Hi Tim

The joint does indeed look well flooded with solder, so it ought to be ok. The Blackburn shouldn't come in to land like an express train anyway! The wheels look good, with the tread pattern looking appropriate for the type. What will you do regarding the wheel inners? A ply disc perhaps?

P.S. Tim, I know precious little about motor/battery set-ups in electric models, but I've seen a few being flown. I realise good battery access is essential for removal for charging etc. How will you install/replace the pack in the Blackburn? Will it be via the cockpit opening? I'm also curous where you obtained your oleo springs from Tim, as these can sometimes be problematic to find.

Brian,

If you scroll back up a bit, you'll see where I've started to plank the top of the cowl.  This 6" by 7" section will also double as the battery hatch - plenty of room to slide a 5S 4000Mah pack in and out!

Re the springs; would you believe that I was gifted a Tupperware box full of assorted springs a couple of years back?

tim

Hi Tim

Yes, got it.    I'd missed it on first glance, but I see it now

Okaaaay..... so now I've chopped out the dummy air outlets....


.....added the side strakes from 3/16 triangular balsa.....


.....not to mention the start of the wing fairings!


Oh, and added a bit of conduit inside the cowl to suggest No1 cylinder too!

Nice Tim!

The bit of conduit is certainly effective.........

Some significant progress over the last few days!

I've knocked up a windscreen frame from 1/64 ply (with an internal frame from BBQ skewers.  The driver is a 1/5 item from Pete's Pilots.


The struts have been faired in with balsa - 1/4"  LE stock to be exact.  Not my idea, but the brainchild of my partner.  She's smart like that.


Seemed a good idea to bolt the fuselage parts together.....


.....followed by the wings!




I even managed to persuade Netty to heft the B2 and give it some sort of scale! 

Ah Tim

See I've got your cygnet plan here and I've been eyeing it up for the past month or so to go onto the "to build list". But if this were published I would definitely build it! Your builds are straight forward and practical as well as geared to us renewable energy types. The fact that it is not a Tiggy makes it all the more attractive. If it doesn't get in the free bin I'll just have to purchase the plan.

Keep er lit

Shane

Thanks for the comments, Shane!  I have to admit that the B2 is turning out to to be more complex than the Ciggie though....

Right-oh, on with the cladding!

I'm using the Aluclad in two ways.  Firstly as nature intended - burnished and polished and, secondly, scuffed up with a Scotchpad and then doused in Brasso...


Here's the fin.  The swagelines are pieces of cord CA'd to the fin prior to cladding.

Now that's looking rather good Tim! 

I can't believe you ever had doubts about it flying. It'll be fine! And,as Shane mentioned earlier, all the more appealing for not being a Tiger Moth.

P.S. Am I correct in thinking you got the rivet effect with the end of a bit of tube, as is often the case?

That tailskid is a bit Carp!!

Or is it that the rest of the model is so stunning that it stands out? A good size too. Are you 'foiling' the whole fuselage or using litho in places?

Cracking job as ever

Ian.

That tailskid is a bit Carp!!

Agreed, Mr R.  It is, however, very functional in it can be used to hang the fuselage on the wall of the garage for storage!   The proper one has this, which is somwhat more complex and hangs off the sternpost itself;


I know that you're referred to as the 'Lord of Lith' in certain circles, but I'm staying with the foil for the entire fuselage I think - it'll ensure a uniformity of finsh.  Besides which my previous attempts at shaping lithoplate have been truly piteous at best..................

Bri, yes that's a hi-tech piece of brass tube used to press the 'rivets'.  Simple, and the Brasso leaves a black residue in the indentations so made.

tim

Hi Tim

Yes I'd noticed the residue in the pics. Really adds that final bit of convincing detail! 

That tailskid isn't unlike that fitted to some Tiger Moths.

Brian,

More black residue tomorrow, methinks......

Fuselage looks stunningly good.
Did you pre-coat the fuselage with anything before you applied the metal tape? Or does it all start to fall off in about 3 weeks time! 

Gordon

Wow! That looks fantastic Tim.

This is a lovely job.  Will it be attending any Fly-Ins when it's done?

Alan

Nice job Tim. It certainly illustrates how well Aluclad can be used.

Are there likely to be any radio issues with all that metal coating?  And might you be at the Scale Weekend at Old Warden in 2012 Tim?  I wouldn't mind a closer look!

Thanks Gents!

Gordon, the fuselage has been given a layer of tissue and dope, as per the recommendations inn the Aluclad instructions.

Alan, assuming the thing actually flies than I'm hoping to tout it around some of the fly-ins this season.

Brian,  The Scale Weekend at OW would have to be considered as compulsory!  I've yet to fly the Cygnet there, so hopefully the pair will be on the flightline at some point!  It's always nice to picture the model alongside the full-sized aeroplane.  Some years ago I built a small (40") Desoutter Mk1, and it was nice to see it alongside the big version!

As regards possible radio interference/blanking I did have a chat with Mr Machinsky (who knows a bit about this sort of stuff), and he couldn't forsee a problem.  Mind you, I might just run the aerials outsiide the fuselage for peace of mind!

I've spent several hours today indenting the fuselage with various diameters of bras tube in order to emulate the rivets of the big B2.  Then out came the Brasso again, with the result that the rivets are now filled with black residue, which has toned down the starkness of the bare fuselage considerable!

tim

Hi Tim

I've looked at the MIck Reeves Metalcoat as a way of getting a metalised finish in the past, but Aluclad looks to be easier to use. It appears to accommodate compound curves very well too.

The OW Scale Weekend has also been pretty much compulsory for me too over the past 30 odd years. I think I've missed about 3 of them in all that time. It was/is also a chance to meet some well known modelling names. I've bumped into the likes of Dennis Bryant before today, and lets not forget the late great Boddo. It just isn't be the same without him. One bloke I don't miss is Dave Bishop. He had the most annoying habit of sticking his microphone right under your nose while you were flying. That I can do without.

Did you see that incident a couple of years back when the big petrol engined Cessna collected a glider in it's undercarriage on a low-ish pass? A bit of excitement there! I flew my old DB Moth at OW for many years Tim, but I finally retired it a few months back after 20 odd years of regular flying. I have a kit here for another, and hopefully I'll have it with me for 2012.

Brian,

OW is a fair old journey from your neck of the woods, isn't it? Do you camp?  We've taken the caravan a couple of times, but everything depends on thre weather forecast these days.....

OK, back to the rivets!

tim

Hi Tim

Those rivets look superb. The overlaps (or what look like overlaps) add to the overall effect too. 

Yes, Old Warden is a near 450 mile round trip for me Tim, but as a predominantly scale modeller I don't miss it if I can help it. It isn't the event it was back in the late 70's/early 80's, when they used to hand out a little sticker to put on your transmitter for Tx control purposes. My Tx sticker in (I think) 1983 was No. 309! These days of course it seems like there are barely half that number actively flying at the event, but I still wouldn't miss it. I usually try to get accommodation in a local B&B Tim, as there are one or two quite nice ones in the area. I used to stay at a particularly nice farmhouse B&B just off the A1 outside Biggleswade, near a Sex Shop (yes, really), but the prices got a bit silly so these days I generally suffer the weekend in one of those unspeakable Travelodge places. I am an SVAS member, so if I'm lucky enough to speak to the right person I can sometimes get to leave my model in the corner of one of the hangars overnight. Saves the car being broken into.