Topic: BT 1/6 scale F4U Corsair

Hello

As I promised, I'll upload some photos of my build.

I started to build the model in October 2009. As I'm going to college I don't have much time, except weekends, to build the model. This Christmas holidays are just perfect for building. 
I did some changes in material selection due to high prices of balsa wood in my neighborhood. So for basic construction I used 4mm plywood and 5 x 5 mm linden lattices.




















That's it for now. I'll begin with tail section tomorrow.

Regards,
                   Robert

subscribed 

Lookin good 

looking good robert....enjoy the planking.......

what retracts are you using?....you might check out John Ranson's build on RSCB in the states....some excellent reference material/photo's of his build............although electric.........which is something to consider...mine will have a laser 200V.....when i get back to it........

dave

I'm in 

Steve

Watching 

Good luck and keep at it 

@ thescaleman

Well, I think that I'll do the retracts myself according the plan... Well, my uncle is a metal turner so he'll do the job for me... I still don't know what engine I will use but I plan to use a larger (45 or 50 ccm) engine... I'm afraid that final weight of the model (20 lbs) will be too much for 26 ccm engine to pull it through the air... I'm very inexperienced in that field, , so any input is welcome...

@ everybody
Thanks for your input... I'll supply you with pictures when I'll be able to...

looks cool!!

@ thescaleman

Well, I think that I'll do the retracts myself according the plan... Well, my uncle is a metal turner so he'll do the job for me... I still don't know what engine I will use but I plan to use a larger (45 or 50 ccm) engine... I'm afraid that final weight of the model (20 lbs) will be too much for 26 ccm engine to pull it through the air... I'm very inexperienced in that field, , so any input is welcome...

@ everybody
Thanks for your input... I'll supply you with pictures when I'll be able to...

I'm building a p51d mustang which is 1/5 scale, My plane's final weight is expected to be between 22-30 pounds. I need at least a 41cc engine to pull it through the air. I would personally recommend that you use something along the lines of 41-50cc for the engine.

I don't know where in the USA you are, but in many US states the height above sea level and high ambient temperatures has a lot to do with the large engines fitted.

If Brian Taylor flew the prototype on a 1.50 4 stroke, then it'll definately fly perfectly well at sea level (i.e. most of the UK) and in cool temperatures on a 1.80 4-stroke, which is 30cc.

A Zenoah 38cc would probably be over powering this thing, and you're rapidly getting into engine sizes which will stick so far out of the cowling that it makes all the effort of building a complex scale model seem questionable in my honest opinion. Your milage may vary of course...

Edit: Just seen OP is in Croatia...

Is where you live particularly hot in summer or high altitude?

laser V200 is a perfect match for this....or a laser 180.......

laser V200 is a perfect match for this....or a laser 180.......

And will drink pant wettingly expensive glow fuel whilst weeing nasty slimy residue all over the fus.

Got to be petrol, in my humble opinion.

@ jamie_duff

Summer temperatures are between 25 and 35 Celsius and 174 m above sea level... I was thinking of 30 - 40 ccm petrol engines... Well, all the fuss comes from my local club where people fly way overpowered planes...

laser V200 is a perfect match for this....or a laser 180.......

Rob
The Laser 200v or even 240v is the perfect engine. Brian's construction methods in my opinion are not suited to large petrols (unless you do plenty of beefing up at the front end). The prototype that Brian built, flew on a Laser 150, albeit it was slightly under 15lbs.
As regards the slimy residue off the glow fuel, just use a good quality fuel proofer such as klassKote.
Just my 2p worth.
Richard

A 2 inch square hole in the cowling of one of these for a huge single cylinder petrol to hang out of really makes the whole exercise of a BT build a total waste of time IMHO. Looking at Richard's lovely build on here, it's a major undertaking and a labour of love. I just couldn't bring myself to do all that work then have a petrol engine showing. I've nothing against petrol engines whatsoever, but if they don't fit inside the cowling it's not a scale model.

It's a large model and will cost a reasonable amount to build. Running costs should be expected to be proportionate to this, no? I think it's reasonable to expect it to cost more to run than a .40 sport model 

If glow fuel residue is a major concern, then why not consider copying John Ranson's (johnr on here) electric set up in his Brian Taylor Corsair? It can be found on RCSB, and is a lovely example with speakers and R2800 sounds. The best bit is that it looks like a Corsair from the outside and there's nothing to ruin the lines from outside 

quite agree that man.....

YouTube             - Brian Taylor Corsair.

Laser 200v.  Weight 19lbs. 

                                                 Dave.

Astonishing performance of engine, plane and pilot...   Your build is fabulous...  It really made me change my mind... I think I'll start to save money for Laser 200v... It is a bit out of my student budget but the way it pulls the plane through the air...  

told you so........

pick one up second hand...i did...........not much goes wrong with a laser!!

Hello Rob540,

I wish you lots of endurance with this project....

Regards,

MFranco

Anyone else spotted this new range of Electric retracts for 15lbs and over models ? they seem well suited to the Brain Taylor warbird range of plans www.bobsworkshop.co.uk DB Airless Retracts 
Dave

Any hints where to find a second hand Laser 200V? 

And the build goes on...

I started to work on the tailplane section...

I started to plank the horizontal stabilizer today... It goes well, for now... Here I also made a slight deviation from the original plan... Instead of planking with one layer of 2 mm balsa I'll plank with 2 layers of 1 mm balsa.
The grain of first layer will go:
=============
============= 

And the grain of the second layer will go:
//////////////////\\\\\\\\\\\\\\\\\\\
//////////////////\\\\\\\\\\\\\\\\\\\

My father says that the construction will be much more rigid than single layer planking...

Your father is correct, the skin will be very stiff, but the second layer wont be helping to carry the primary loads on the tailplane and the lamination itself implies a layer of heavy glue at the wrong end of the aeroplane.

If it were me, I'd be inclined to stick to Brian Taylor's plan in this area and just use a single layer at twice the thickness 

Any hints where to find a second hand Laser 200V? 

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230422569625&ssPageName=ADME:B:SS:GB:1123

                                         Dave.

Thank You, but it is a bit too soon to buy engine now... Still a lot of work to do with the plane... And I have to buy radio and batteries and some other stuff first... I plan to buy engine somewhere in may or june... Classes have started again on college so I can work only on weekends when I come home...

That's OK, shows they turn up occasionally . If you haven't already done so try putting a saved search on ebay that's how I found this one.  Just to show what turns up I have a new in box Saito 325 radial that came from ebay Australia for just half price of a new one from a shop in UK.
 Building a Traplet plans General Western Meteor to give it some airtime it will then be put into an enlarged BT Corsair (sometime)

                                           Dave.

I put it into a saved search...  Hope something will pop up when I'll look for it...

Anyone else spotted this new range of Electric retracts for 15lbs and over models ? they seem well suited to the Brain Taylor warbird range of plans Bobs Workshop DB Airless Retracts 
Dave

I like the look of those!  They've got to be so much better than pneumatic  systems ( seems to me like the most unreliable thing from the planet "Unreliable" ).   
Rather like the look of that EDF balancer as well

Nice build by the way,  subscribed

Alan

Very nice retracts. I wonder what the pricing's like?

Hi    Pup Cam i'm keeping my eye on the electric retracts for future builds as for the Ducted Fan Balancer guess what Santa brought me this Crimbo  not had chance to test as yet but will post in a seperate thread when i do
Dave

not had chance to test as yet but will post in a seperate thread when i do

Look forward to hearing all about it Dave

Hello gents

Did some progress since last time. Not too much, but it still is progress.




 






Both halves are finished and now all I have to do is glue them together...

As I said before, isn't that a lot of weight of glue exactly where you don't want it? I really hate to comment negatively on someone's build thread but that just doesn't strike me as a good idea 

I hope this doesn't offend, that's not my intention at all. I can just see you ending up with a tailplane which is weaker spanwise (it doesn't need torsional strength because the elevator actuation is from the fuselage) and needing a lot more nose weight to balance than you'd need if you'd done it conventionally. 

No, no, nothing said that offends me. I was worried about weight myself, but I had consultations with my father (long time carpenter) and we looked at glue specifications and glue consumption is 100 - 150 g of raw glue per square meter. About 50% of glue is solvent, so it comes down to 50 - 75 g of extra weight per square meter. 

just one question.......why laminate 2 layers of 1/16" (i'm guessing it's 1/16") when Brian used only one?.......my mate did something similar on the 83" BT spit....but that was the fuz in 2 sheets of 1/32" which turned out to be very strong.......did you reduce the thickness of the ribs to compensate for the extra sheeting?.........if you are not careful you might end up with a thicker elevator, if this was built for a comp it may be noticed........

just my 2p worth.........

did you get sorted with that laser V200 on ebay from the states?

I think, if I recall correctly, that according to plan, it should be laminated with 3/32" balsa (I'm currently not at home so I don't have access to the plans). Concerning the measurements, I stick to the plan and I don't want to alter anything on that field. I think that ailerons, rudder and elevator should be covered in fabric but I will sheet them with balsa and at that point I will pay attention to thickness of the ribs.

I'm building this plane primarily for my soul and for flying. I don't think it will see too much competition, just some our local Croatian "air meetings" with couple of low passes and fly-by's. 

Unfortunatelly, due to lack of glow fuel support in Croatia, I think I will go the petrol route with some 40cc  (2.40 cu in) engine.   

 

Well, I was at home for the weekend, so I tackled the old bird a bit...

I made second half of tailplane and made both fin halves... I sanded them with 150 grit sandpaper, filled pin holes with JUB white Acrylic Wood Filler and then sanded it with 320 grit sandpaper... There are still some imperfections, but I will sand them out before gluing the halves together... I didn't do much because I ran out of balsa wood...

Anyway, here are some photos...

Hello gents... A little question regarding servos... For this model size would it be enough to fit 10 kg servos for rudder and elevator and 2 x 7 kg servos (6,9 @ 4,8 V, but I will run servos on 6 V), one for each aileron?