royal_chris

Hello,
since the digital work on my Aichi D3A1 "Val" design is done so far, I had started a new CAD project for the coming winter... a Boomerang. This plane is mostly unknown here in Europe. Besides some few fans and scratch buildings, there is simply no kit in that size available. I love the wonderful shapes of the boomer. In my opinion it would even look fantastic with no camouflage painted on.
As the Aichi, this will be a 100% wood design as well. Hopefully this will be ready for prototyping, when the Aichi is done. I am currently checking gear manufacturer. This whole area (along with the cowl) was the most challenging part for me and has not been mastered yet.

A few numbers:
1:4.5 scale
appr. weight 24lb/12kg
wingspan 2,44m
wing loading: ca 100g/dm2
length: 1,82m

Any comments and suggestions highly appreciated.

F86_SABRE

Hi Chris,

Drawings look very neat! Nice project as well. Can I ask you which 3D CAD program you are using? Solidworks?

Reuben

royal_chris

Hi Reuben,

this was done in TurboCAD, while the basic former setup is usually done in DevFus.

Thanks,
Chris

F86_SABRE

Very nice Chris. DevFus is a PROFILI product..correct? Never knew it had results this good. Might try it

Thanks....I will be watching

Reuben

royal_chris

Yes it is done by stefano who runs profili as well. Devfus is growing, since there's an opportunity to edit formers individually, this is an important step. But do keep in mind, that it's only 60-70% (setting geometry of fuse, formers, sheeting, lightning holes, spars, former splitting) of the former work, the rest is done in turbocad manually.

royal_chris

The digital work was finished tonight [8D]

It's now up to me to sort any piece, finish the fuse plans and put all pieces in order to cut (the nesting). The plans for the outer wing panels were done a couple of weeks ago. Two german mates will build the prototypes, since I have to finish the Val first and will build my Boomer then. I'll post some photos, if the guys don't forget to take them while building

jymster

My Feedback: (9)

Hey Chris, nice work on your Boomer so far. I am a real Boomerang fan, it is my favourite fighter. You should also check out our thread here: http://www.rcuniverse.com/forum/m_15...omerang/tm.htm to see the work we are doing on our boomerand projects in Australia.

regards,

James.

royal_chris

Hi James,

we already exchanged a few words via email....a couple of months ago, when I started my Boomer
I have read your thread a couple of times. Are those bommers ready to take off or what's to be done?

regards,
christopher

royal_chris

Plans are done, cnc data is prepared, wood ordered, the cutter will start this week for the prototype kits. I am eagerly awaiting the first three wood kits Will post some pics of the cut.

royal_chris

The first 3 kits lasercut were packed and shipped today within Germany. Will post some pics of the building, if the guys don't forget to take some.

This is actually the first time, other people are building one of my designs, so I'm pretty excited how this works out. There will definitely be some major or minor revisions to be done, but hopefully most of the brain build does function in wood.

The 6mm ply pieces and 3mm novotex hinge parts were cut by a cnc mill, the rest via laser. The firewall is actually 276mm/10,86" wide. Engine options are big.

bartman77

hi nice size boomerang that u have started , a few years back i to built a .60 size one , nice to see some more

bartman77

just a few more of mine

royal_chris

Hi,

they look sweet. The look for the boomernag in general  looks sweet for me, not a cruel fighter...but 20mm speak a different language

btw I received an email by somebody asking for some laser cutting for a different project. I couldn't answer via email, so this is my response:
I do not have an own laser cutter. I am doing the drawings and giving the cutting files to someone else, cutting the kits for me.

Thanks a lot.

PS the building has already started, will post some pictures soon.

royal_chris

As promised, some pictures of the the building progress.
Any rib of this kit has building tabs and position of those on are clearly marked with stronger line weight for easy positioning.
Fin and stab will both be sheeted with 1.5mm balsa, while elevator and rudder will be covered with fabric, like the original boomer had.



As mentioned, anything in the tail is made out of 3mm balsa hard selection to keep it light, but strong. Except for the TE, LE and stab saddle. They are all included and cut from 6mm balsa.


The hinge pieces and rudder horns shown are all included. This method works fine and is easier to install smooth rudder control, than drilling and aligning common hinges. To be fair: this novotex method weights a bit more.


As you can see, the top stringer has notches for easy positioning and assembling of the rear formers. Six side stringers are included (those with strong curves), for the rest is cut from 3mm balsa. The fuselage setup is done with two halfs. Both are assembled on 6x8mm balsa spars. The fin TE is also the last former, as common.

royal_chris

Another work was done by one of my fellows: first assembly (no glue). Bottom half is missing, but it starts to look like a boomerang 

royal_chris

bartman77

wow fast building looking very good ,    nice job

geesybeesy

Wow This looks like a great model.
Is it possible to blow it up to 1:4 scale. I'm looking for my next project and would love to do a Boomer!

jymster

My Feedback: (9)

G'day mate, you can also follow our thread on the Boomer here: [link=http://www.rcuniverse.com/forum/m_1539660/mpage_15/key_/tm.htm]http://www.rcuniverse.com/forum/m_1539660/mpage_15/key_/tm.htm[/link]

royal_chris

Hi,
this kit is 1:4,5 simply cause of the wingspan and limited space to load it into our car. I won't do a different scale, cause that would be too much work. As mentioned there's another boomer building thread with 1:4 scale and glass fuse as far as I remember. If you want to do woodbuilding and 1:4,5 is fine for you, please send me your contact. Thanks Christopher

royal_chris

Some progress on the fuse and center wing section:







The center wing panel is glued permanently to the fuselage.
The weight before adding the center wing panel was 2,2kg (appr. 5lbs).

royal_chris

The sheeting is finished, wing fairing started. This is where my mate's built is at:




He did some major modifications on the first former/firewall. This is how it looks scale for the ring collector of the radial. Although he's gonna fire it with a 3W twin, he wanted it scale. The starboard exhaust pipe will be funtional in his boomerang.

The actual firewall cut does include some big cooling cutouts and pieces to build up some kind of tube below the cowl for engine cooling.

Christopher

petronio

Looks really good!

jymster

My Feedback: (9)

Hi Chris, looking good mate. You might want to check your canopy rails, though, as they should angle downwards toward the back of the fuse. This allows the canopy to slide back without the rails protruding out of the fuselage.

Please have a look at these images:

royal_chris

Hi,

this is exactly the way it's shown in my plans. My mate built it different, don't ask me why ;-)
Any building photograph is taken from him, I'm currently not building any boomer. He's doing the prototype and maiden flight. By the way, it's planned to the the maiden within the first half of 2011.

Thank you,
Christopher