Thread Tools
Feb 02, 2017, 06:40 AM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
Good luck on that Craig. I worked on the E-3C software back in the 80s. Would love to build one of them and make the rotodome act as a lifting surface. Although weighing a bunch it had some lifting behavior according to some i have talked to.

EDFs are not in my wheelhouse yet. One of the guys in my club buys a lot of RTF models with those and doesn't seem to mind only getting a few minutes of flying time. That puts me off.
Sign up now
to remove ads between posts
Oct 15, 2018, 06:35 AM
Registered User
acrowot's Avatar
Thread OP
Hi to everyone
sorry its been so long since I have updated this thread life just seems to be go go go With repairs and other projects keep popping up like people giving me there smashed up ARTF,s that they no longer want ie a Hanger 9 P40 ,Seagull Hawker Seafury, and a HET-RC F18 of 15 years ago that have all been rebuilt and now part of my 20 odd plane collection.

But the Comet has not been thrown in the corner and forgotten when I do get a chance she gets bought out so over the next week or so I will find the pictures that I have taken and post them up.

So this set of photos are of the left wing panel just a copy of the right wing panel being built a lot easier the second time round all straight forward in picture 2 you can see wing joiner
Oct 15, 2018, 06:46 AM
Registered User
acrowot's Avatar
Thread OP
In these pictures is the wing all laid out, I have decided to sheet the whole wing with very light 1/16 balsa this will add a little weight but not much as she will be brushless and have a lot more power so this should not be a problem as long as the all up weight stays about the same as Chris golds Nimrod conversion which flew well on speed 400
Tonight I will find some more pictures and post them up

Many thanks geof
Oct 16, 2018, 08:46 AM
Registered User
acrowot's Avatar
Thread OP
Hi as promised I have now found some more pictures these are of the outer wing panels.
On the plan the wings are sheeted up to the main spar then cap strips but I have sheeted the whole wing which was easy due to the wing been mounted on all the jacks
.
The first 3 pictures are showing the bottom of the outer wing panels showing all the ribs and the servo mounts for the ailerons and flaps.

Last 3 pictures just showing the top sheeting nice strong and light.
Oct 16, 2018, 09:00 AM
Registered User
acrowot's Avatar
Thread OP
This is where the fun and games started sheeting the bottom of the outer wing panels.

So the idea was to make new jacks and place them where needed to stop the wing from warping and keeping the built in washout when I glued the sheeting in place which thankfully it all worked out nicely.
the last 2 photos is the sheeting glued in place on the jacks
the final pictures are the panels all finished with the servo boxes all cut out I have left the ailerons and flaps in place for the moment but easy to cut out.

more to come
many thanks geof
Last edited by acrowot; Oct 18, 2018 at 06:19 AM.
Oct 18, 2018, 08:54 AM
Registered User
acrowot's Avatar
Thread OP
Now I started back with the centre section first job was fitting the main undercarriage plates.
On the plan they were made from laminated light ply but with the possibility of flying of short grass I decided to make them from normal ply to fit some hobbyking retracts.
I do feel some times that building to light ends up with weak areas and repairs which do end up adding weight and frustration especially around undercarriage areas.

Mains retracts
https://hobbyking.com/en_us/servoles...ount-2pcs.html
l
Nose retract
https://hobbyking.com/en_us/servoles...1mm-mount.html

The main retracts where a little tight to fit in the wing so I made up some jacks and managed to get the plate were I needed it, so I can fit a set of 4 wheel bogies in or a single wheel when I fly it of grass.
On the plan and instructions there is not much said about the thrust lines of the motors so looking at the plan they seem to be set at zero to the incident line of the wing.
With the wing setup at zero I fitted a speed 400 motor into the motor nacelles fitted a prop adaptor with a balsa upright
The front of the motor nacelle was placed at the right height and the rear end jacked up to match the set square then glued in.

more to follow Geof
Oct 18, 2018, 09:46 AM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
I put those retracts on my Martin 4-0-4; one thing you need to do is NEVER flip the switch to retract the gear with the fuselage upside down. The design of the steerable nose gear assembly literally pulled the clevis out of the steering arm as it got caught when the free-floating part of the assembly got into the wrong place. The manufacturer did not take into consideration the free-floating piece and that it would be in the wrong place with the unit upside down.
Luckily I was able to drill a new hole in the arm; while I don't have as wide of a range it still works OK. Other than that the gear is very solid and works well.

Good luck, this is coming along nicely sir.

Kevin
Oct 19, 2018, 04:35 AM
Registered User
acrowot's Avatar
Thread OP
Hi Kevin

many thanks on the information on the nose wheel retract I would never of known until I broke it.

I have just started reading your build on the martin 4-0-4 there is some great information and ideas on it and i'm only on page 10 flaps been one idea for a future Vickers VC10 (and I like your helper Bunny the cat) I had a helper as well mine used to sit under my chair getting covered in balsa dust when I was sanding ha ha

Geof
Oct 19, 2018, 05:27 AM
Registered User
acrowot's Avatar
Thread OP
After fitting the motor nacelles we now move onto joining the wing centre section together quit straight forward.

The centre front and rear brace’s is a cut and fit job.
You have to cut the wing ribs so the brace fits flush in ribs 1,2,3 then the braces have to be glued with epoxy then pined in place as there is a little tension as the brace’s bends from rib 3 to rib 1 then to rib 3 the other side.

The last 2 pictures show the wing before sheeting the centre section.

More to come many thanks geof
geof
Oct 19, 2018, 06:20 AM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
Geof,

Thanks for the kind words on the 4-0-4. It has been a labor of love. So much stuff I had to figure out it has really beat me up, but I have learned a lot. Still, I'm already getting a level of satisfaction on this build. I probably could have been more careful in the build process and made her lighter than 1.7 kg. She will have a wing cubic loading of 9.3, and with 445 Watts at 80% throttle she should cruise on 50% throttle. Lack of prop clearance has me a bit concerned, as I wish I could have used a 10 inch prop instead of the 8. I may end up doing surgery on 1047s to get the pitch I need in the size required.

The Comet, like the Caravelle (I'm considering one) has the challenge of scale engine inlets, and producing enough thrust. I have been encouraged to build light and lighter still if I do progress the Caravelle. Only two a burning on that one and they aren't big turbofans.

Bunny is still my helper; she just jumped in my lap as I sit here in the dark getting started on my Friday enjoying my coffee. :-)

Great build, your craftsmanship is very good sir.

Kevin
Oct 19, 2018, 08:14 AM
Registered User
Dirty Dee's Avatar
great progress!
Oct 19, 2018, 10:17 AM
Registered User
acrowot's Avatar
Thread OP
thanks for the kind words it does not matter how long we have been building for there is always something new to learn.
the comet has been a labour of love as well learning new ways of doing things I just wish I could devote more time to it.

I am just going through all my pictures and should be up to date in a few days were I have just joined the wings to the fuselage.

Keep on going with your build it can get hard at times when you keep bumping into problems and doubt keeps coming into things and when it fly's you think what was all the worry over been there done that many times in 30 years.

As for the Caravelle that would be a lovely project and with so many different sized EDFs you should find a scale to suit.

have a good weekend Geof
Oct 19, 2018, 05:29 PM
Official Boat Bum
Eddie P's Avatar
A classic! Great to see.
Oct 20, 2018, 12:35 AM
Registered User
AntiArf's Avatar
Good to see you back on the Comet. Flown both of the two smaller ones now, maybe someday I'll get motivated to try the larger one.
On the steerable retract, those things seem to have less than perfect geometry. Ideally the metal arm should be longer, so that the pushrod pivot point that is connected to the sliding plastic piece is perfectly aligned with the retract strut rotation center, with the steering servo in it's center postion. The way they have it, there would be less travel in one direction. The pushrod also should be supported vertically somewhere near the retract so that it is always perfectly aligned with the strut rotation center. The pusrhod guide will need to allow a bit of side to side motion, but no up and down slop. Done properly the wheel will not turn when the retract is activated up and down, or at least will only turn very little, which helps if the door clearance is tight. I've heard some folks mix the radio to disable steering as soon as the gear switch is retracted, so that they can't accidentally turn the wheels with the rudder and have a door clashing issue, but I've never bothered with that and just set the geometry so that the wheel turns as little as possible during retraction.
Oct 24, 2018, 04:38 AM
Registered User
acrowot's Avatar
Thread OP
Hi AntiArf

thanks for the info on the retracts will have a look into it.
I love those 2 Comets they fly really well and to have the fan in the fuselage now that's a clever bit of thinking genius.
Just finished reading about your Tu104 build beautiful such craftsmanship and finished to such a high standard and flys with so much power maybe I need to build Chris Golds VC10 for 30mm fans

Geof
Last edited by acrowot; Oct 24, 2018 at 04:57 AM.


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
New Product Chris Golds' twin MF480 Vigilante. bipeflyer Electric Ducted Fan Jet Talk 121 Jul 09, 2014 11:44 AM
B-2 bomber by Chris Golds LotusTRBO Electric Ducted Fan Jet Talk 287 Nov 12, 2008 10:01 AM
Chris Williams 1/4 Minimoa RCheroske Scale Sailplanes 11 Nov 18, 2007 05:42 AM
Starting to build the DH108 Swallow of Chris Golds Knippels Electric Ducted Fan Jet Talk 2 Aug 10, 2004 03:59 PM
Hawker hunter (chris golds) ryan d. Electric Ducted Fan Jet Talk 11 Aug 25, 2002 04:20 AM