jymster

My Feedback: (9)

Richard,

I will ask Matt Denning. Let me get back to you.

James.

puma79

Jmyster, I didnt hear from John with regard to the laser cut kit! Any chances of getting in contact with him to grab it? Drop me a call on 0412 133 622.

Also for interest, I have acquired an actual CAC Boomerang airframe that I have commenced the restoration of. A46-167 which served with 85 squadron in WA - squad code SH-Z. I will be posting pictures of her here on RCU very shortly.

I really want to get started on getting the model started!

I look forward to hearing back from you.

The Raven

I hope you have contacted Matt Denning and Richard Hourigan, they have a lot of expertise with full sized Boomerang aircraft.

jymster

My Feedback: (9)

Richard,

I would say that Stewart Wilson is correct, however it would probably be NACA 2206 not NACA 2206.1. The Wirraway used NACA 2215 at the root and NACA 2209 at the tip. Similarly, the DC-3 used NACA 2215 at root and NACA 2206 at tip. Here is a useful tool for comparison: http://www.pagendarm.de/trapp/progra...les/NACA4.html

I am looking at the Overhaul and Repair Manual, and it states that the root aerofoil is NACA 2215, but does not specify the tip section. However it lists the chord at the root to be 90" and at the tip, 54" (theoretical at Sta. No. 216). Also lists a 2 deg incidence, relative to fuse datum. Washout is Nil to Sta. No. 133 and 1 deg. 23 min. between Sta. No. 133 and Sta. No. 216. Centre section also has 2 deg. incidence.

The NACA 2206 section is basically a thinner version of NACA 2215, so it would make sense.

If you would like a copy of the Overhaul and Repair manual on CD, let me know. I also have the Manual of Operating Instructions.

Regards,

James.

Bundy

Hi James

Thanks for that. It confirms the information I have and we'll just have to take Stewart Wilson's reference to a NACA 2206.1 as a typo. I do have some concerns about using such a thin section and how it might affect its tip stalling but it is just a model and the experimenting is fun.

My measurements put station 216 right at the very outer wing tip so I'll hang the tip there is 'space', loft out to it from the NACA 2215 centre section and then cut out to the planform shape. If my maths is right the 2 degrees incidence built into the centre section will turn into just 0.62 degrees of positive incidence at the tip relative to the fuselage datum when the 1 degree and 23 minutes washout is applied. With 1 degree of positive incidence on the tailplane it will give 1 degree of longitudinal dihedral which sits nicely in accepted norms for a stable model. Means it should fly??

I've had to halt building on the 1/4 scale Boomerang for the moment. The $1400 worth of EVO Lite lipos I'd bought for this project have 'puffed' on me without ever getting airborne or even fired in anger. The EVO 20s and Thunderpower lipos I've had for years now continue to perform flawlessly so I'm at a loss to explain what has happen. We're currently talking with Model Flight and hope to have them replaced but it has dented the confidence in large electrics and modern lipos big time.

So to keep the Boomerang project alive I've started work on a 1/6th scale version. I'll use 3D CAD software almost exclusively this time and am very seriously looking at building it as a fully composite job. Most importantly it will fly on one lipo pack and not four! The 1/4 scale version is not dead but it will take a while now to rebuild enough confidence in the batteries and the money involved to get the big one flying.

Richard

Bundy

Hi All

I'm very pleased to report that the 1/4 scale electric Boomerang is back on track. Model Flight and Flight Power have not only agreed to replace the original puffed batteries but have offered to replace them with matched F3A packs so there should be shortage in the power department. I've upgraded my charger to the new Schulze Next Generation 6.30-5 and V-balancers so all should be sweet now.

I've been searching for an identity for this Boomerang and I've settled on A46-128 U-Beaut-2. Researching the nose art for Flt Lt Don Goode's ride has only brought up black and white pictures with some nice close ups - thanks Craig!

I've managed to sweet talk my very talented wife Patsy - check out her web site www.artbyPatti.com - to put down her airbrush for a night and have a go at colouring up this black and white nose art pic. There is a brief written description of the colours used but not much more. Attached are the original scan, her first go at colouring it and a B&W scan of her colour version.

Can anyone offer any clues to what colours might have been in the original?

It is an off beat piece of art with Flt Lt Don Goode being depicted as a magician riding a broomstick dressed in a suit and spurs while shooting green bottles through a shang-hai. The two blobs in the bottom right corner first looked like a bikini top but this art work was painted in 1943/44 and the bikini wasn't launched on the world until 1946. I'm thinking it is meant to be a Pacific island atoll far below as he flies by with his head in the clouds.

The hat is I think meant to be a magician's hat but a normal magician's hat is black with a red or white band - not at all like this one. Trying to guess the colours from the grey scale image and the written description, we've come up with this as a first try. The original pic is taken with light shining from above and with the curve of the cowl it is very hard to see exactly what was going on. Can anyone shed any light on the original detail?

Richard

Peter_OZ

My Feedback: (1)

at a guess I would say that would have used what ever paint was available, most likely RAF or RAAF colours. think the red will be RAF roundel red, same for the blue. The green looks to be RAF dark green, standard camo on a mk 9 spit

Bundy

Bit of an update on this 1/4 scale electric Boomerang project.

The main focus has been on the cowl which has seen an awful lot of hours without much to show on the model. Firstly getting the curves of the cowl looking right and then the discovery of some software 'bugs' have caused their fair share of frustrations. Once the 3D shape was finalized it was 'sliced' up and 6mm MDF sections were cut out and assembled into a very large wooden plug. I'm now at the stage of fairing this plug out and then to make a female mold. From this the finish cowl will be produced. The pics should tell the story.

The prop in the pic is a 30 x 20 inch AXI wooden prop. No doubt a nice bit of work but at $140 it would make flying not fun! Handling it you get the feeling that just the slightest touch with a tough clump of grass would splinter it. So I'm looking at how to use it as a plug to produce my own carbon fibre version. The other option is to carve my own wooden props on the CNC which has its own challenges but again possible in theory.

I'm still waiting for the promised replacement batteries from Flite Power so no news on what power is going to available yet.

I'm having trouble getting 3/8" piano hinges for the flaps but I should be able to get 1/2". This means I can get on with the wings now I know what is available.

The tail end is pretty well sorted with just one more panel needing work. The main fairing between the fin and tailplane is quite a prominent set of panels on the full size so I might make a molding of this and cast individual panels to get the right look.

I've given up trying to set a date when it will fly because it just puts pressure on which makes the whole build 'unfun'. She will fly when its ready!

Richard

jymster

My Feedback: (9)

Richard,

I should have talked to you about the cowl sooner. The shape is all wrong on all 3-views we have found. I have begun to modify the best 3-view we have to show the correct shape. See these pics:

Bundy

Hi James

Thanks for the input. I know I've fudged the lines of this cowl and had hoped not too noticeably but not to be

I discovered these cowl pics very late on the fuselage build and when I tried to graft these new shapes into what I already had built I had to compromise. The fact that you have noticed the errors means more work is needed. I'll have another go at grafting on to what is already built . The problem is the fuselage is too deep where it attaches to the cowl. To get that round shape at the front lip of the cowl it means the height of the cowl is set by the width. This height then has to blend back into the over depth fuselage which wrecks the profile lines.

Like I said I'll have another go at blending but if it can't be done I'll have some big decisions to make. I'm not interested in making something that is noticeably wrong just to get it flying. I would really be looking at starting again this time with all the drawing, pics and 3 views on hand from the start. I know this was a cardinal sin of scale building to start building with out all the available documentation sorted before building started but the origins of this project were more to do with chance than plan.

If I have to start again I will really look at doing in 1/5th scale I think. Big enough to cope with our grass strip and still have a presence but it will fit my CNC machine so much better.

Interesting times ahead

Richard

jymster

My Feedback: (9)

Richard,

It would be a shame to start over! John had the same problem with his cowl, as the Hesselhurst plans are also too deep in the cowl area. But John was able to get the correct opening shape, even with the depth of the fuse. Just takes a bit of persistence, I guess. This is the biggest problem area on all drawings (and models) I have seen. It is quite noticeable when you compare to the real thing. Do you happen to know Brian Fooks up there in QLD? His 1/6 boomer is probably the best I've seen. He says he has some original CAC drawings somewhere, but I am yet to see them. I'm not sure what information the drawings cover. But I am first on the list to get a copy of them when he "finds" them! I will try to find his contact details for you.

James.

Bundy

Hi James

Thanks heaps for the CD. Sure is more than a few hours reading in there to take it all in.

Well I've made the decision today to hand this 1/4 scale Boomerang build over to Brian who I originally started this build with back in about October and I'll build a 1/5th scale composite version. There are a whole host of reasons that have lead to this decision with the cowl inaccuracies being the last straw that tipped it over the edge.

Very briefly some of these reasons are the obvious scale issues as shown in the attached pic. This shows the Rod Heselhurst plan in light colour overlaid with the Polish 3 view which seems to be accepted as the best to work from. What I've built so far could be fixed but it would involve demolishing the fuselage back to about mid wing.

The electric component of this 1/4 scale build has caused issues. A very specialized prop is needed for this motor to work. It takes 6 weeks from Czech and $140 and is very breakable. I might be able to make my own from carbon fibre but if this tips over on its nose it would bend motor shafts or burn out the ESC or the like. I could make my own from wood on the CNC but fitting a 30"+ blank in my machine wouldn't work without very expense mods.

Other minor issues like finding when built to 1/4 scale it will not fit in the back of a Falcon ute with out a special cradle to hang it out the back and needing 2 people to load and unload it have all help make the decision. I want this Boomerang to be an every day plane that is flown lots - not a few times a year special occasion plane.

So I'm very excited about this 1/5th version. It will fly on one battery for 10min+, use a standard sub $20 prop, be around 20lb AUW, easy for one person to load and gives me the opportunity to get the scale fidelity right by starting with all the good information and having the 3D software to begin with. I'm also very excited about the possibilities of full composite construction. I've read heaps about it, done numerous small scale tests and this is as good a project as any to try it out for real. A carbon fibre Boomerang sure is a unique mix!

Richard

CAC_Boomerang

Hi Folks,

as you know, I also build a Boomerang in a 1/4,5 scale. (For more information please see my old post )

I have build the basis wing and then the project stopps regarding the same reasons like yours.

But now, as I see the attached drawing from Richard, I hope to can go ahead in building the Boom.

And now my question. Is it possible to get the CD with the original information, ( the attached drawing looks very promising to build a good fuselage)

If John or you Richard can send it over, I will pay for the shipping .
Maybe you can deposit a Zip File to download somewhere.

Thanks in advance.

Bernd

Bundy

Hi Guys

Time to breath some life back into my Boomerang project. I've finished and successfully flown both my B-25 and Brian Taylor Corsair so now have a clear building board.

I've also been busy building a new CNC router this one 4 times bigger now cutting 1200 x 600 sheets as well as 150mm of Z travel to allow 3D carving of those complex curvy bits. It will also allow me to cut my own 30" x 20" props for the big AXI and will even do 3 bladed versions which will be fun to play with. Batteries are all sorted with EvoLite 5S packs flying both the Mitchell and Corsair with ease.

I've gone back to basics and redrawn my Boomerang model from scratch and I'm happy with the new shape. This Rhino 3D software allows you to now slice up this model and get the cross sectional shape of anywhere to make perfectly fitting formers even for the nasty bits around the wing fairings.

I'm really excited again with this project. I had thought about doing it as fully composite job but test pieces aren't showing any significant weight savings to justify the complexities and costs of molding. I like planking anyway.

Richard

jymster

My Feedback: (9)

Richard,

Looking great, mate. Sorry I have not had a chance to get the photo CD to you. We have just sold our house and are busy packing up our lives into many boxes!

Your new router looks great! I will have to talk to you about a 3-bladed scale flying prop for my FW190.

James.

Bundy

Work has begun on this new Boomerang. It is always good to see something emerge from all the hours spent just drawing bits. This new router is miles quicker than the old HobbyCNC one cutting much quicker than I can draw and the bed size means I can cut all the formers and ribs for this 1/4 scale version as whole pieces making things that much quicker again.

I've started playing with cutting a few foam 30" x 20" props and all looks very workable. It will take a deal more work to build suitable jigs to make a wooden version and to work out the laminations to save cutting it from solid timber. I'm also looking at cutting a plug for the porcupine exhaust from solid timber and using it as a plug to mold from. Will have to wait and see how that works out for real but the 3DCut simulator says it can be done.

Richard

puma79

Hey guys! thought I would quickly post and give you a quick update on my 133% Boomer (from Airborne Plans orig). I finally managed to start the damn thing almost 3 years or more after I first got the plans and started this thread! I think Im the last person to give it a go!

I think I mentioned it a while ago, but I am restoring a CA-12 Boomerang A46-73 to airworthy which has taken a lot of time. I will include a few pics for you all to look at.

I will post more as it happens, you can also check out http://returntoflight.aviationadvertiser.com.au which is the website I set up to follow the restoration. If any of you also feel like throwing a donation across the table feel free!!!!!!! We need all the support we can get!

The CAC Boomer model will fly, and I am putting a 3W-75i in it for power, and I will keep posting as I progress on it.

Bundy

Morning Ben and All

Great to see another Boomerang ( both a good sized model and full-size ) being built. I'm looking forward to following your full size restoration on what looks a very attractive web site and progress on your model build.

Are you planning on doing an accurate retract set up? The angles involved to make it look right both when down and fit correctly when up really dictate a custom built unit unless there is something out there I haven't seen??

I've been playing around cutting my own 30 X 20 prop to suit the big AXI motor I'm using. I'm happy now that this can be done altho I haven't fully finished the one in the pic so now I'm moving onto the wing structure which means designing the retract system. I've also drawn up the tail feathers and how I'm going to mount them altho I haven't built them yet either - too many other fun bits to do first.

I'm also about to start cutting the plug for the cowl and canopy now I've worked out how to use this Cut3D which really is a top bit of gear. No doubt Ben you've been made aware of the errors in the front end of the Airborne plan? If you would like a copy of the 3d virtual model I've evolved just give a yell but I guess you have the real thing there for reference!

Happy building

Richard

The Raven

Any chance someone will make this available as a laser cut kit (or similar). Would be a lovely project to do but, alas my scratchbuilding skills are limited (hence why I'd prefer a kit).

jymster

My Feedback: (9)

Raven,

There is already a laser kit available for the Airborne plans, from Model Draughting Services: [email protected] . Dave has 100% (72") and 133% (96") versions of the Airborne plans currently. However, you might be able to entice Richard (Bundy) to cut you something, as I am sure his will be the most accurate boomer going around. Though he probably does not have any plans, as such.

Regards,

James.

Peter_OZ

My Feedback: (1)

Very nice to see these projects progressing as the Boomerang has a lot of character. Have seen the full size a few times up here at flying meets.

If you were fitting larger petrol motors such as DA-85 then I would recommend the 3 blade Solo prop. It is avariable puitch hub that you set according to engine type and performance required. Couple of the guys up here are using them and they pull like amallee bull.

One guy has them in his 220" B17 hanging off 4 x DA-50s

cheers
Peter

Bundy

I'm sure we could organize something Raven when this project finally gets into the air.

I've just cut parts for 2 more of these 1200mm x 600mm CNC routers for other people so there should be no shortage of people able to cut the parts for you. I'm only too happy to share the drawing files I'm developing if it allows other people to build this bit of Australian history and slows the ARF take over if only a little bit.

I would hope to have something developed enough for other people to have a go at in the next few months.

Richard

jymster

My Feedback: (9)

Richard,

I would also be interested to find out more about the CNC router kit. Please send me an email.

Regards,

James.

The Raven

That would be much appreciated. By all means, do not rush to do this as it would be a long term build for myself and I'm sure you have enough to deal with at the moment.

Look forward to watching the progress.

Bundy

Morning

I'm looking at the retract angles of the full size Boomerang so I can design suitable mounts into the wing structure of my 1/4 scale version.

The 'up' geometry seems straight forward with both the Airborne plan and various 3 views agreeing that 19 degrees from a perpendicular drawn from the datum is where the wheel sits. The down angle is a little more rubbery. The Airborne plan is suggesting a forward rake of 6 degrees but it is not clear if this is measured from the fuselage datum or from the wing chord which is itself 2 degrees to the datum. 3 views are indicating something closer to 10 degrees from the wing's chord line.

Can anyone tell me what is the actual angle of forward rake of the Boomerang's main gear either from the fuselage datum or the wing chord line?

Thanks
Richard