RC India

(http://www.tnjmodels.rchomepage.com/images/dh-88hr.jpg)

The de Havilland DH.88 Comet was a twin-engined British aircraft designed for the 1934 MacRobertson Air Race. Three examples took part in the race and one of them won it. The type set many aviation records during the race and afterwards, as a pioneer mail plane. The modern features and clean lines of the DH.88, especially in the striking colours of Grosvenor House, the race winner, make it a true design classic

I've based my build on the general layout and dimensions of the FT Cruiser - http://flitetest.com/articles/ft-cruiser-build

Decided to go Corro because the Depron available here is not of an ideal density, and my flying ground needs a tougher Landing Gear, which, again, needs a firm anchoring. Plus, Corro is a great material to work with: very high strength to weight ratio, and good toughness & impact resistance

The stock of Corro I bought about 8-10 years ago is now practically exhausted. After scrounging around managed to salvage some 4 mm & 2 mm - in multi-colours; expect a very outlandish Corrmet :D :D

Someone is going places! All the best Sire - this one will be a show stopper.

I will be working out the construction methodology as I go along. As mentioned above, I have used the general dimensions of the FT Cruiser.

The build log is detailed: I do get lots of requests regarding Corro Builds - hope this helps

(http://www.flickr.com/photos/102005136@N03/11065379136/in/photostream/)

Mark out the Corro. This is painful if you can't sit on the floor with a bust knee  8) :D :D

(http://www.flickr.com/photos/102005136@N03/11065392006/in/photostream/)

Correct way to score Corro for a bend. Use a Phillips screwdriver, and angle it well. The idea is to crush the flute, not cut through it

Quote from: VC on November 26, 2013, 06:35:32 PM
Someone is going places! All the best Sire - this one will be a show stopper.

Thanks VC :D  BTW, are the pictures visible?

Before I forget, Specs!!

Span - 50"
Chord - 9"
Length - 30""

Power:
2 X 2826-1400 KV Turnigy Motors
Cw & CCw props - 9*47
2 X 30 A Red Brick ESC
4 Servos ( 2 X 17 gm, 2 X 9 gm)

Excited to see it sir :)

Sanjay ji, you always inspired to build, nice plane, eagerly waiting...

Cutting the side reinforcements for the fuse. Normally I would use Corro, but as will be evident later, a lot of the fuse will be cuy, and the additional strength is needed. Used 2 mm Ply

Thanks Anand, thanks Mjet  :thanks:

sanjay sir check this out
http://blis.kicks-ass.net/p38.htm

Final finishing, and gluing. Oh, I use SR 998 for all Corro to Corro and Corro to wood. Works well for me - the old Avi has 200 flights and innumerable bashes - still going strong :D

I do use epoxy, Cyano, and hot glue when the occasion demands  ;) ;D

(http://www.flickr.com/photos/102005136@N03/11065407726/in/photostream/)

Shaping the spars

Wing half cut out of 2 mm Corro

http://www.flickr.com/photos/102005136@N03/11065331885/in/photostream/lightbox/ (http://www.flickr.com/photos/102005136@N03/11065331885/in/photostream/lightbox/)

Used 4 mm Corro for the Aileron & wing back. The centre part can be cut for flaps if needed

Wing halves joined on spar, Wing ends with Ailerons glued

Wing

This one needs a nose block at the wing LE as I plan a bolt-down wing. Cut some scrap balsa, glued it together, and did some sanding

 :o how many builds in a month sir  :salute:  :bow: :bow:
good luck sir :thumbsup:  excited to see one more buity ;D

Thanks, Tushar :D

Fuse folded up at the sides and top. The aft end is not yet glued.

This is going to be a fun plane to fly... all the best for the build sir...
Eagerly awaiting for it to be completed...

Thanks Topalle.

Just waiting on a few parts

Rai Coromodels Pvt. Ltd.

Sanjay Sir, It is comming out beautifully. I am following it very closely for my coro build as well (a different model - has been on the bench for many months now. I always had valid reasons for not working on it  though 8-) :P )

@VC sir :rofl:

Quote from: VC on November 26, 2013, 08:57:33 PM
Rai Coromodels Pvt. Ltd.

VC....really captures the scope and breadth of it :D  :D

Thanks Flying Brick...hope it charges you up to finish your model ;)

All glued up :D

The rear part of the fuse is glued with SR 998, and then on the corner I use hot glue. The Tail feathers (4 mm Corro) are only mock fitted at this stage - I will only finalise and glue after the wing is set so the alignment of these w.r.t. the wing is square

I cut a hatch out after folding the fuse nose and gluing. A distance piece is kept for reinforcement, and a cheapie hatch lock is used. Looks like an alligator with jaws open!! The LiPo will go in here

If you want to view the detail, a high-res pic is here:

http://www.flickr.com/photos/102005136@N03/11065519503/in/photostream/lightbox/

http://www.flickr.com/photos/102005136@N03/11065471684/ (http://www.flickr.com/photos/102005136@N03/11065471684/)

An awful moment  :-\ :-\  After all that work, I take an axe and start chopping  :'( :'( :violent: :violent:

The top part of the fuse is cut away. The wing will be below; the arrangement will soon become clear as the build progresses

Quote from: VC on November 26, 2013, 08:57:33 PM
Rai Coromodels Pvt. Ltd.

Rai Coromodels Pvt. Unlimited.  8-)

 :o Pvt.?

They're all in the public domain now, with plans and build instructions...;)

Apoloigies Sanjay sir for twisting that...but we so love you and your models ...:D

 :giggle: :giggle: I actually made it Public Unlimited but thought let someone else to identify it 8-)

 :bow: :bow: Now Rai sir will soon present an Airbus A380 made of Coro :bow:

Arvind - I will do that after you manage to repair one of your models, wake up on time, and come flying

 :bow: :bow: Tomorrow:salute:

Nacelles made. Used 10 mm ply for the firewalls.

Box of the motor. I wonder.............time will tell  ;) ;) ;D ;D

I see that a Canopy  ;)

Sir  :salute: :salute: You see what I see  ;D ;D

this one is going to be seriously heavy
awesome sir this is just marvellous

Sanjay sir we do think alike  ;D ;D  :bow:

Thanks Sandy Saheb

Nitesh, if it's seriously heavy, it can never fly  :rofl:

I'm targeting 1.2~1.3 Kg. That compares well with an Avispad of 1.1 ~ 1.2, but this has over 400 W compared to 300 on an Avi.

I figure the Airframe will be 700 gms, the L/G 80, battery 250~270 and the electronics the balance. The battery wire harness is nearly 80-90 grams  8-)

I thought it'll be around 1.5 to 1.7kg.
btw sir we both are building a thing at the same time but with different materials. FT FLYER.

I'm not making nor have made the flyer. Good luck though

I meant we both are building something at the same time. I did'nt mean the same thing

Landing gear needs to be robust for the field I fly in. This is surprisingly light for it's strength - total of about 60 grams the pair

Tail Gear

Awesome build Rai, and it is so timely for coro build. I am building Focker and logically joining the dots
Fuse building technique is a great help
Coro is a great medium few people use it as there are more sites for depron builds here is one

Gr8 link for all the coro builders
http://www.spadtothebone.org/PDF/Coro%20Cub.pdf

Hmmm

Query:Rai why did you decide to make spar wing support  like that...instead the one shown in ft plan?

Wing (continued)

Nacelles test fitted and located. Always good to screw the servo mount screws into something solid: one side spar, other ice cream stick glued to the corro. If the servo moves fractionally in operation, translates to some flutter/imprecision on control surface

Wiring harness. One battery to 2 motors. 14 AWG Si wire, + connectors.

Girish, whose electronic fundas are up there with the best, recommended using 100 uF capacitors as noise suppressors because of the long power wire

Sir your collection of tools is just awesome

Thank you Nitesh. Been collecting for over 30 years :D

be carefull tonight everything might vanish  ;D

Time to start closing up now.

Wires temporarily locked in.

Please note: whatever you put in should be planned so that if you have to repair/replace/maintain it can be easily done. I have seen guys sticking servos with cyano! Even some manufacturers and popular websites suggest this. Don't do it! There is always a smarter way

Corro models with a wing joint should have a wing-wrap. On rubber band attached wings, it gives a good base for the bands to rest without cutting the wing

I used a narrower than usual wrap because it is going to go into the fuse

The good thing about SR 998 is you let it almost dry, then push the 2 sides together firmly. Usually there is enough grip so you don't have to hold or clamp...a relief :D. Then leave it for an hour or so

Another view of the wing servo. Fits firmly on 2 screws.

Wing done. Now, back to the fuse  ;D ;D

Quote from: iwincar on November 28, 2013, 10:46:54 AM
Query:Rai why did you decide to make spar wing support  like that...instead the one shown in ft plan?

Mr. iwincar, (I don't know you well enough to dispense with the Mister) see Reply# 1. I am not building a FT Cruiser. I am building a corro model of my own design using the external dimensions of the FT Cruiser

The tail ( horizontal stab ) looks small the plane... is it okay sir?

Thank you for that expert assessment. I guess we'll find out when we try to fly it :)  :)

Actually, you might be comparing it with a trainer. This is not a trainer, and needs a fair amount of manouevrability

Fitting the Horns

Push Rod

Support plates for main L/G

Inside ply plate for L/G

Wing fit-up

I am nowhere near you sir... long way to go for me...

Landing Gear

Wing Mount Blind Nuts

The extra length of the wing mounting bolts is trimmed off

2 ply plates used to secure the hatch

Hatch fitted

Assembling & fitting the nacelles

Fitting the Elevator & Rudder Servos

Wing Nacelles fitted

Assembled. Still have to add the turtle deck cowling....will probably do so after the maiden, if successful. Model is heavy at 1.3 Kg, about 100 grams more than I would like  :(

Oops: forget to mention - lower photo shows 2 spirit levels being used to ensure stab is parallel to the wing  ;D

Testing the controls

http://www.youtube.com/watch?v=5JvG9nROIpU&feature=youtu.be (http://www.youtube.com/watch?v=5JvG9nROIpU&feature=youtu.be)

Whew!!!  ;D ;D

 :salute:

With those 2 monster engines it will tear the sky....

:hatsoff:

Hope so Saurabh. Little worried about the weight :(

awesome plane sir :) :)  and also the color combinations.:)

Sent from my Micromax A110 using Tapatalk

Thanks Sudipto. Hope it flies ;)

all the best sir  ^_^

Sent from my Micromax A110 using Tapatalk

:thumbsup:

Looking forward to the maiden video.

Thanks Anwar bhai. Probably this coming Saturday

Like always sir, Excellent !!!  :salute:

{:)} {:)} {:)} {:)} {:)} {:)}

Thanks Anand :D:)

Very beautifull sir Excellent

Thanks Nitesh

Sanjay Sir, any updates on this or the ft racer?

Waiting for the field to clear from the mela. FT Racer is waiting - both my 2826 motors are on the Corromet; even the BB and Nutball are gathering dust :(

Sanjay Sir, very neat and beautiful build with a great color combination.... :hatsoff: :hatsoff: :hatsoff: {:)} {:)} {:)}
Extension wire shown in Post #57 are normal wires ( used in Home Electrification) and available at LHS?
Can we  use normal home  Electrical wires as extension?

Mohan, it is written in Post # 47 itself that these are 14 AWG Silicon wires. These are available at LHS (RCB, RCD)

After a fair amount of inanities, a successful maiden  ;D ;D

Watch the fun before take-off  :rofl: :rofl:



[url]http://www.youtube.com/watch?v=TRleYZzdK54&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw]http://www.youtube.com/watch?v=AGwFJSwxXa4&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw[url]

[url]http://www.youtube.com/watch?v=TRleYZzdK54&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw (http://www.youtube.com/watch?v=AGwFJSwxXa4&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw%5Burl)

Another

http://www.youtube.com/watch?v=TRleYZzdK54&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw (http://www.youtube.com/watch?v=TRleYZzdK54&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw)

And again  :banghead: :violent: :violent: :violent: :rofl:

http://www.youtube.com/watch?v=ZeJVIHqsecg&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw (http://www.youtube.com/watch?v=ZeJVIHqsecg&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw)

Finally  ;D ;D

http://www.youtube.com/watch?v=nRu2qP_qCN4&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw (http://www.youtube.com/watch?v=nRu2qP_qCN4&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw)

Girish flying - as usual aiming for his favourite tree  >:D >:D

Finally!

Maiden  8) 8)

http://www.youtube.com/watch?v=LALdp_xxwGU&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw (http://www.youtube.com/watch?v=LALdp_xxwGU&feature=c4-overview&list=UUQhf5Pkzb8t7lzTwN0AIYEw)

Girish had a tough time landing! Needs a fairly high landing speed and a clear runway.

Wow!!
Great plane sir..

Great plane sir.....Looking forward to seeing it fly on Wednesday

Thanks, Topalle and Maahin

wow sir very nice {:)} {:)}, Sanjay sir one question if u don't mind "konsi chakki ka aata khate ho" ?
:salute:

 :giggle: :giggle: :thanks:

Sanjay sir ki apni chakki hai..powered by 3542 brushless motor...200A ESC and 5 5000mah batteries in parallel...prop se atta pista hai aur methanol fuel pe roti banti hai ;)

Looks like an actual WW2 bomber...

@ Girish Sir :rofl: :giggle:

 :giggle: :giggle:

Great Video Sir Now i am A Big Fan of you sir

Very  good build and Cong's :hatsoff: for the maiden.you always  inspired to build {:)}

Wonderful, action packed model...hear that sound of twin engines rustling...anyone's whos planning to make this, its not a light model, the wing loading is high and needs quite some speed and preferably flaps to land, and not forget be prepared to use a lot of rudder or AR mixing...it will turn at a dime, amazingly agile; those two motors rushing air back at half wing span make the ailerons very sensitive, so while the rolls are great a lot of adverse yaw is introduced, see 2.05 - 2.09...some aileron differential alongwith A/R mixing will be great...and some motor differential will make this plane a historical coro build, atleast in rcbolt history...

I had to abort landing atleast thrice...too many people on the field and I'm used to bringing planes straight in slowly.. There was a sudden gust of crosswind wind about 3 ft above ground while landing which made it cartwheel at the last moment...

but an amazing build and a complete action flyer...true to the original WWII comet...

Great Model Sanjay sir as i always had admired it, Flies really well {:)} {:)} {:)} {:)}....Girish had a great time maidening it :giggle: :giggle: :giggle: :giggle:. It is a real fast flier and looks really nice while flying.

Finally it took off after so many servo reversals.... ;D ;)...

Good Job done!!! :thumbsup:

Quote from: girishsarwal on December 23, 2013, 08:46:19 AM
Sanjay sir ki apni chakki hai..powered by 3542 brushless motor...200A ESC and 5 5000mah batteries in parallel...prop se atta pista hai aur methanol fuel pe roti banti hai ;)

LMFAO !! :D :D :D

 :thanks: Mohan Sandeep Achin  :salute: :salute:

sanjay sir.....no words .....   {:)} {:)} {:)} {:)} {:)}    :bow: :bow: :bow: :bow: :bow:   :hatsoff: :hatsoff: :hatsoff: :hatsoff: :hatsoff:


I was always scared of using coro as building material....just because of the coro flutes  :violent:

but now you have motivated and inspired me to build uing coro. :thanks: :thanks: :thanks:

Good. Now build  :thumbsup: :thumbsup: