Peter_OZ

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why not?

P4Patti

Hi Dave

The plug for the canopy has been wet fine sanded over the last week or so and is ready to pull the canopy and frame. So yes it will have the canopy when it first flies. The plug for the canopy was made from plaster and then sealed with epoxy which impregnates the surface making it a hard composite which you can work to a really fine, mirror like finish. It's a good way to make smooth plugs for anything. Actually, Richard cnc-ed the negative shape into foam and poured the plaster into that and then worked it up from there.

We've only been using the A123's the last 6 months or so, and not a lot of flying due to the weather but so far really happy with them. They perform as advertised. We buy them from China for around $9 per cell, 3.3v, 2.3Ahr, 72 grams, charge at up to 10C and discharge at some ridiculous C rating. We have a 7 cell pack in my profile Jumbo built-in (one pack stays in the plane, no pack swapping) and recharges in 10 minutes. A 10 minute flight and 10 minute charge and fly again - brilliant. They also have a more robust chemistry (none of that fire in the boot stuff), balancing is no where near as critical as the lipos and you can store them for 2 1/2 years on the shelf with no problems.

For the Boomerang it means one pack worth around $400 will fly it as opposed to 4x lipos with another set as a swap over. No contest really.

The only 2 down sides are that for the same amount of power they're about 25% heavie,r but for warbirds where you need nose weight it's an advantage. The Boomerang, Corsair and the Lanc all fit that and it helps. The other thing is getting a big enough charger/s to take advantage of the quick charge they can do. Richard is working on a transportable charging system for the field.

The Boomerang should be flying in the next month or so, Richard is a little distracted at the moment with the CompARF Spit Santa left him but the second half of the year should see the focus back on the Lanc starting totally from scratch from factory blue prints. It will be 11'w/s, fully composite , complete with all 130,000 "outy" rivets and 4 x electric motors. Very much on this year's "must do list"!

Aloha [8D]
Patti

Peter_OZ

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enjoy those rivets. What technique is he using? I have never had much luck with outies

ticketec

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outies?..... ummm

Hey Pattie,

I have posted some updates on the lancaster thread to not clag up this thread un-necessarily

http://www.rcuniverse.com/forum/m_80...m.htm#10243479

Thanks

dave

P4Patti

Oh come on Dave, get with the technical speak Outies as opposed to innies. Had a look at the Lanc thread, great to see that going again too - noted the date, couldn't believe it's been 12 months [X(]

Pete, there's definitely a technique, you may want to go and make yourself a cuppa before launching into reading this

He creates a 3D model of the plane from factory blue prints (in the case of the Lancaster) then draws the lines of rivets from nose to tail so they flow with the curve of the fuse. Then dividse it up into panel lines and extract each panel with the rivet lines marked and then "smashes" each panel (that's a fancy command in Rhino that flattens out a compound curve into a 2D pattern). The computer then arrays the individual rivets at the appropriate scale spacing onto the 2D drawing. Richard has made a special domed embossing tool so the cnc machine can mark the rivets and then cuts out the panel. The panels are then applied to a smooth plug made from the original 3D model .......... moulded etc. Easy That's a quick explanation anyway. It's worked well on the Boomerang and the next one will be easier now that the method is substantially sorted!

Back to work before it rains again!

cheers
Patti

Peter_OZ

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Bugger! and I thought it would be some techno thing hehe

I have used pin heads successfully, snip off 2/3rds of the shaft, apply a drop of CA to the remaining shaft then insert! Works well but is slow and labourious and does add weight. Also limited in scale sizing.

I used this on the 1/4 scale Cub.

Peter_OZ

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wel I'm off to cook myself and the boy scrambled eggs and bacon with mushrooms! My 50th treat to myself.

rastuswatermelon

Hi guys great to see the boomer is still underway , thought u might have been building boats.  When will this rain stop???

P4Patti

Well, look what the rain brings out You'd need a boat out your way wouldn't you? The Boomer is coming along good-o and should be ready for a flight in the next month or so, if there's a dry enough field anywhere in Qld!! Just had a friend around who took one of the spare/early trial wings from the mould home and did a quick paint job on it to see how the detail comes up. Looks a million dollars! Just the right amount of rivets and panel lines to make it really interesting and not look toy like.

There's been a bit of a distraction since Christmas though. Mrs Santa bought Richard a Comp ARF 1/4 scale Spitty which he is electrifying with a Hacker A-100 (100cc electric equivalent) and a 170A ESC all powered by 48 A123 batteries. Be seeing you soon then
It looks great next to the Boomer.

cheers
Patti

Peter_OZ

My Feedback: (1)

just as well I have floats for the 1/4 scale Cub!!

rastuswatermelon

Comp arf spitty !!!!!   someones been a very good boy .  Yea its wet out here, smells swampy too,  The a123 setup is nice , looking  foward to seeing it in action.  Cheers Chris

ticketec

My Feedback: (2)

Hey Patti,

Finaly a week of sunshine!!!! has your flying field dried out? I haven't even bothered with mine yet but i'm getting itchy to go flying!!

Thanks

dave

royal_chris

Hello there,
I'd like to ask the boomerang experts, if you have some reliable info about the instruments?
Ifound three different source showing the panel itself not being symmetrical in width. Is that a mistake due to photography distortion? The restored boomers seems to have some mahor changes in geometry of their actual panel shape. Corner not that rounded etc. (?)

Do you have good sources for this including the imstruments looking? Did they copy/adapt british or american instrument?

Thanks alot
Christopher

PS we're currently building/revising here: http://www.rcuniverse.com/forum/m_10044020/tm.htm

JÖRÖ

Just found this thread!!! Amazing Boomerang! I'll be watching!
-Jörö-

jymster

My Feedback: (9)

Hi Chris,

Does this help:

desertrat65

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Hey Patti,

Did your Boomerang ever fly? It has been more than a year and no update!

Regards, Adam.

P4Patti

Hi Adam

Short answer - no, not yet! However, it really isn't far away, I'll attach some pics. There have been loads of other projects going on over the last year including a whole lot of pilot making which I've had to somewhat reluctantly scale right back so that we could fit in plane building! One of the 1/4 scale Boomerangs pulled from the mould was almost ready to fly but it turned out to be tail heavy so Richard made another and took the servos out of the tail end and moved everything forward. At one stage he almost went with a petrol engine but thankfully came to his senses in time and designed the new one for electric The main problem is that with all the alterations over the time the drawing on the computer doesn't exactly match what was moulded as there was a fair bit of hand finishing of the plug.. This makes cutting accurate internals difficult and down to a bit of cut and adjust then recut. But since it's so near to flying we're going to give it another push and get it over the line - it will be interesting to finally see it in the air and old Tom, the Boomerang pilot from ww2 is always on our tail about it too!

Thanks for the nudge

cheers
Patti

desertrat65

My Feedback: (1)

Hi Patti,

Thanks for the reply. The Boomerang looks fantastic!

I was toying with the idea of building my own 1/4 scale Boomerang to fit my 250 Moki engine into. I was wondering what brand retracts that you have used.
Are they Robarts?

Regards, Adam.

P4Patti

Adam, the retracts are the Robart Ziroli 1/5 Texan gear but with longer Robostrut legs. In theory they should be strong enough but unproven as yet! The retraction and fit into the wheel well is good but the mounting bearers have to go in at interesting angles to make it work.

cheers
Patti

P4Patti

Hello again. Work on the Boomerang has begun again. It's been so cold that nothing is growing outside so we have had a bit of time for once. The new port wing is joined with the internals in place and last night we layed up the starboard wing which is now curing in the sun. The starboard aileron plug is almost finished so next is the parting board and a mould for it.

We installed the pull-pull cables for the elevator and rudder yesterday so that is now working. Once both wings are on the big balance test will be able to be done. We're thinking that it may need 6 battery packs to balance and where to put radio gear for easy access is still an issue. But having it back on the work bench there is definitely a flight in sight for this project.

cheers
Patti

Oakey

Patti
that bird just looks the business it is fantastic. i am so glad that you and richard are back onto it! keep the posts coming, how is the lightening? is there a thread for it?
Settling into the new house, new man cave almost set up.

cheers

C

WI53072

Patti,

You and Richard do such fantastic work!

Paul

P4Patti

Paul, Richard is the brains behind all the great projects but it's nice to part of the team

The batteries arrived not long after my last post and it soon became clear that the Boomer wasn't going to balance without about an additional 2kg up front! This was pushing the AUW so close to 25kg and Richard didn't want to go over that limit. In Australia we have a 7-25kg heavy model category which requires a heavy model inspector to sign off on the build and the flying of each person who will fly it but over 25kg it becomes Giant category and that's a whole new ball game of inspections, paper work and red tape. Also, the undercarriage would probably be tested once it got that heavy.

Richard did some research on the C of G problem and found this http://dbdesignbureau.buckmasterfami..._boomerang.htm To cut a long story short, there is a lot of contraversey over the 3 views and actual dimensions. According to this website, the 3 view that Richard took all the drawings off has the wing about 14mm too far forward (in 1/4 scale). This would make a noticable difference to the balance moving the whole wing back.

It's a real dilema as the mould we have isn't going to balance easily. We looked at all sorts of ideas to make the rear fuse much lighter, to the point of ridiculous but in the end it really needs redoing. Richard has taken the dimensions from the website mentioned and completely redrawn the 3D model with the wing in the right position which required relofting all the fairings. That's now done but to start again from scratch just didn't appeal at the moment with other projects waiting in the wings. He has decided to go to the top of his bucket list and get on with his P-38 Lightning first. The Boomerang project is an ongoing experiment in 3D design and composite construction which has led to the success of the Thunderbolt. http://www.rcuniverse.com/forum/m_11..._1/key_/tm.htm

It's a matter of mustering the enthusiasm to start again and apply the methods that made the Thunderbolt so successful to a new Boomerang. It's still a work in progress!

cheers
Patti

BOLTMAN

My Feedback: (1)

It's 10 years today since this thread was started and no sign of a model Boomerang flying in Australia!

Well it is now my turn to step up and try to get a Boomerang going.

I remember as a youngster seeing Noel Whitehead's Boomerang which is pictured early in this thread and watching it fly at the Wagga WWII weekend. From memory it flew really well.

I also enjoy the Australian factor to this aircraft, being the only fighter to be designed and go into production in this country.

At the start of November last year my wife & I flew from Gladstone Qld to Temora in NSW for the "Warbirds Downunder" airshow. As we got close to Temora and I switched over to the local frequency, a call came over the radio that the museum's Boomerang was airborne for a practise display. My immediate reaction was that I would have liked to have landed already to be able to watch that. As it turned out we soon joined the circuit, landed and taxied to the general aviation parking area which was actually under the display area. Just we shut down the Boomer came whistling over our heads and started into it's practise display. We were fortunate to get to see this up close as people were not allowed to remain in the parking area due to it being under the flightline. As you can imagine with the Boomerang overhead I was in no hurry to get our aircraft tied down and leave the area!

After the successful teaming up with Richard & Patti of Bundaberg on the P-47 project ( see http://www.rcuniverse.com/forum/rc-w...h-build-4.html - my involvement starts at post #92 ), I have now taken on their 1/4 scale Boomerang project.

Richard and Patti ( RAP for short ) have vey kindly given me the airframe as is seen above in post #370. I was bugging RAP about what they were going to do with the airframe as it was at the point that they shelved the project, and if I recall correctly Richard's answer was along the lines of "If you reckon you can make it work, take it and have a go!" I might prove to be crazy but it all looked way to good to be left not finished, so I am going to give it a shot.


As Patti has mentioned, the weight was running away a bit and there was also concerns for the retracts that they had worked around. My plan is to try to reduce the weight as much as possible and I have ordered a set of " Custom Retracts" ( http://www.customretracts.com.au/products.html ) CR-412's to suit this model that should be capable of carrying the expected 25kg finished weight.

Since taking the Boomer on I have slowly been getting together the gear required to see this beast fly. Power will be a DLE 111cc motor that fits nicely in the cowl. I have also managed to source a suitable carbon fibre wing tube which will save over 700 grams ( 25 ounces ) compared to the originally planned aluminium tube. This tube is 40mm in diameter and 1.2m ( 4 feet ) long.



I will continue to post progress as it occurs.

Cheers

Mick

BOLTMAN

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My initial efforts have focused on trying to remove as much weight as possible from the tail end as the Boomer's short nose makes getting C of G right a challange.

To start with I spent several hours with my arm stuck in the back of the fuse trying to sand as much material as possible out of the inside of the composite fuse shell. At this stage the only access into the fuse is through the canopy opening, so this process was quite awkward.

I also cut lightening holes in the trailing edges of the tailplane and fin.


Next I removed material from the former to which the tailwheel attaches. There are 2 hardwood rails that the tailwheel frame actually screws to, so I was able to remove quite a bit from the ply former without compromising strength. This bit still looks a bit rough, I will tidy it up more later.


The former at the rear of the wing also met up with Dr Dremel for some weight reduction treatment.


The forward part of the fuse also had a fair bit of material removed ( compare to pic's 5 & 6 in post #370 above ). I plan on moving the servos even further forward to try to help with balance.


Cheers

Mick