Props4ever

I got this model in trade today.

Main Truss box work is done on the fuselage, some of the lower half formers are glued on to belly of the fuselage and some on both sides. Rest of the model still needs to be built but all templates have already been cut out of MDF material for both fuse and wing ribs.

I am currently wondering since wings, Stab and vertical fins still needed to be build, how about making these with white foam and glass them directly similar to my Super Constellation currently under construction.

Is there anyone who has already build this model, i like to know what i should be aware off before i start working on it. I will add pictures soon.

Feel free to comment and add your larger build progress to this post. Its always better when we can pool our resources and knowledge during the builds.

I look forward to the new challenges this aircraft will present.

Thanks in Advance,

Sammy

aerowoof

Sammy,
I see no reason why you can't use white foam cores but they should be sheeted with 1/8" balsa prior to fiberglassing,that is how my westcraft b-17 is done.I rember bob cambells b-29 from about 25 years ago having a wing fold up but it weighrd around 100 pounds.

Props4ever

Aero/John

I want to avoid sheeting process from foam core wings, for my Connie i will be glassing it with 6oz cloth but before i apply cloth to both wing surfaces i will apply 1-1/2" strips of Carbon fiber on top and bottom of the spars full length and wing joiner tubes, this way spars and wing joiner sections gets sandwiched in and form "I" beams at spars and caps on wing joining tubes to give maximum strength to avoid wing folding, after this i will lay glass on both surfaces of the wing, What do you think of this process on B24 and also on An-22's wings!...

aerowoof

i've used carbon fiber to repair cracked spars years ago and it worked great but it needs to be on end to add rigidity to a surface like a wing.from my understanding you are laying the cf strips flat on the surface then glassing overthem and whatever spars you have.I can see where this will spread theload over a larger area but I think you would have a stronger wing if you inset some cf strips on edge into the wing just behind or infront of the spars 1 " deep would be enough and a knife slit would allow insertion then with the cf laid out on top as you said you would have 2 cf "t" that would make a strong section .especially the center part of the wing where all the engines are.

Props4ever

This is how my spars are glued in the center wing of my Constellation and as mentioned above, i will lay CF strips on top and bottom of these and then lay glassing on the entire wing section.

aerowoof

sammy ,
I don't see any cf unless you have set on edge behind the spars as I see some black but it could be from a marker.If you have the cf inset on it's edge then I missunderstood what you were doing.thought you were placing 1 1/2" cf strips flat on top of the spars then the glass.

Props4ever

John,
I haven't capped the spars yet with CF but i will be doing it shortly, black mark you are referring is from marker.

Props4ever

Design and Weight issues

Getting back to Liberator i have noticed some design and weight concerns on the plans, Design area in concern is in the fuselage where wings plug into it as drawn on the plans with only 2x 1/2" brass/copper tubes going across fuselage to hold and take weight of the wings!, now this doesn't look right at all as it looks very lame and weak design.
As for suggested weight of the complete model is estimated slightly shy of 28lbs dry!, this also doesn't look right according to engines, retracts and electronics suggested in the plans to use compared to shear size of the model itself. It really makes one wonder how come Dan Palmer never build his own designed model/s and tested them before lunching them in the open market....

Props4ever

Here are pictures of current stage in which i recently got this Bomber. Last 2 pictures are of plug for light house clear nose to be completed and vacuum formed and box with 4.5"-6.5" wheels and other stuff including 2 rib templates.

TLH101

My Feedback: (90)

Palmer is famous for "optimistic" weight claims. Many of his plans have been criticized as being "too busy", and not having good building practice. He does not build and fly his model designs, so all testing is done by those who build.
I do remembers someone in the past here on RCU doing a big B-24 and I am pretty sure it was the Palmer design. Just can't remember who it was.

Props4ever

Terry,

I can't imagine how he got away with this kind of stuff all the time, recently on other site i read he has passed away recently but the question still remains about a designer of plane yet he diden't built his own designs to actually teeth out the problems and design flaws!, these same flaws also attributes to ub-normal expected weight issue recommendations also. Well i would really like to meet or get in contact with some one who have built and flown this giant 1/8th scale B24 in the past before i start working on it.

First thing that i would be redesign will be fuselage and wing joining system, i will be making or getting wing tube sleeve out of CF or aluminum and use the wing tube system to hold both wing joints together, this will most likely require 2 wing tubes. First forward tube will start from one side of outer engine pod all the way though the fuselage to other side of outer engine pod, then a rear tube which will remain in between both inner engine pods. These will increase some weight but will become fail safe and very strong design and system to hold wings together firmly.

These are my preliminary design modifying observations and thought around this flaw but if you or anyone else have better design idea please feel free to share it with me.

Props4ever

Man threads roll fast on here!!!

Well i have found that this model's weight is no way close to what suggested by Mr. Palmer!, here is a link of similar 1/8th scale 165" WS scratch built model of B24 by Carl Burshober of Wisconsin.

http://images.google.ca/imgres?imgur...&sz=115&hl=en&

With .91 4 strokes his model flew at 45lbs!!!, i think its little bit underpowered with power to weight ratio!, i will be usiing either .91 2 stokers or .120 4 strokers....

On the other site (RCSB) another dream builder of this model suggested few schemes to me, as i was thinking on lines of Desert camo schemes for my model, well he changed my mind to do a Naval version PB4Y-1 (309 NAMU) Yellow liberator below. With this version i don't have to spend time making gun turrets!!, so few hours will be saved yet it will be very unique model once done in this scheme.

Any other scheme proposals are also welcome, bare metal/polished aluminum one will be considered also, please feel free to post on here.

I will be emailing Carl shortly to see what he can help me with, he has been very helpful and kind in helping in my Connie project also.

Props4ever

I like to know if anyone have more pictures of above mention Liberator, please post them on this thread or email them to me....

Tomcat_104

My Feedback: (42)

Props4ever,

I just ordered a "smaller" B-24 (132" wingspan). You'll be ahead of me so I'll look at your post for education. I was planning on powering my B-24 with 4 RCV90 motors. Do you think that would be okay? I too plan to use carbon fiber on my foam wings.

My dad, who has passed away, flew on a B-24; I'll post his scheme as soon as I can. You may find it interesting, I had a stroke back in 2004 so I build pretty slow now. Good luck and I'll follow your progress with much anticipation.

David

Props4ever

Hi David,

I like to let you know that i will not be starting on B24 until my other current project get completed of gets very close to being completed.

http://www.rcuniverse.com/forum/m_4538333/tm.htm

Currently Connie is my priority now days. I think it's a very good approach to do wings, stabs and fins from foam Vs traditional balsa and ply build, this process really speeds up the building time and its very economical also. As mentioned earlier that i will be changing wing/fuse joining method, I don't really like this part of Palmer's design for my size of a model.

It would be nice to see other schemes also, bring them on!!...For powering your model, what are specs on weight of it?, ifs its in 20-30Lbs range then i think you can get away with .75sz 2 strokers also, ST75s come to mind as they are very string engines but again it will depend on your model's weight and wing loading, you don't want to increase wing loading unless you really have too.


Sammy

Props4ever

From what i have been reading on other sites and threads that suggests i will need to use 1.20sz 2 strokers as this will have quite a bit of weight due to the way its construction is. On the other hand i was thinking of taking fuselage side, top and bottom templates and do foamcore job on its fuselage top, side and bottom, this way it can be done in 2 steps Vs 3 or 4 with ply, stringers, sheeting and glassing...
These are just my thoughts right now, any other idea/s could be considered also, let me know....

Props4ever

What i mean is, making and adding foam structure on top as turtle deck, both side ans belly of truss box that is already there. I may have to detach some of already glued on former halfs in order to incorporate foam pieces....

Props4ever

I am still going through selecting phase for my B24, i just got to know that there were some transport versions of B24s that were produced too, well i would prefer to do transport version over Bomber version as i will not have to make part molds for all the armament found on the Bomber version to vacform. Does anyone have any pictures, drawings and model types for these variants can you post them on here, i will appreciate it, thanks in advance.