Welcome, Guest. Please Login or Register
Stick and Tissue Logo
 
  HomeHelpSearchLoginRegister  
 
 
Pages: 1 2 3 4 
Send Topic Print
Marcoux Bromberg (Read 2742 times)
Reply #27 - Jan 17th, 2019 at 12:31pm

Skyediamonds   Offline
Global Moderator
Enjoying life and all
aspects of modeling
Reno, Nevada

Posts: 2365
****
 
Mike,

Sounds like you're really moving along on this project, despite it seemingly being slow.  I know.  It take an enormous amount of planning to pull it off in the manner befitting of a true scale model.  As the saying goes, "Devil is in the details."  I had to build the entire model in my mind before commiting to the first cut.

I read your response to my Mustang build and I sincerely thank you for taking the time and effort to write.  I've written a response.
 
IP Logged
 
Reply #26 - Jan 17th, 2019 at 8:24am

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
Been working away on the racer, mostly deciding where everything should be. The information on the overall arrangement drawings is very good and relates to each other from sheet to sheet and is very accurate as to scale but the real details are unknown and given there are no actual construction drawings of this airplane, I will have to design it from the inside out. The wing is laid out and the rib locations identified and started to detail the wing ribs. This led me to deciding where the aileron torque tubes would be and the configuration of same. Also have to be sure the torque tubes don't interfere with the flap actuators so that all led to where the actuating controls would be located in the cockpit. That led to where the pilot would be sitting and that would give me a fairly good feel where the stick and rudder pedals would be. So, needed some physical dimensions. I lowered my office chair to where it felt like would be a comfortable sitting arrangement and had my wife take some measurements as seen in the second picture. Then took these dimensions and placed them in the cockpit using some assumptions: head to be three inches from canopy top and back cushion of the seat four inches thick. The drawing shows the floor in relation to the wing root ribs so knew I couldn't be below that so laid in my dimensions and roughed in a pilot. This gave me the location of the stick and rudder pedals and the actual seat height. Going forward will design the aileron/elevator control arrangement and lay that in and then finish the torque tube/flap actuators. I've started a comm string with the New England Air Museum to see if there are any cockpit photos. Should know soon.
Mike
 

Rib_Structure.jpg (58 KB | 5 )
Rib_Structure.jpg
Pilot_Layout.jpg (72 KB | 6 )
Pilot_Layout.jpg

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #25 - Jan 11th, 2019 at 11:19am

Sky9pilot   Offline
Administrator
Stick & Tissue
Kelso, WA 98626 USA

Posts: 10266
*****
 
You're welcome Mike...that's what we're here for, to assist one another!! Smiley
 

If God is your Co-pilot...switch seats...
Your attitude will determine your altitude!- John Maxwell
And ye shall know the truth, and the truth shall set you free. Jn 8:32
IP Logged
 
Reply #24 - Jan 11th, 2019 at 8:31am

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
Tom - Thank you for repointing me to MS Word. Sometimes the obvious isn't always.
Mike
 

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #23 - Jan 10th, 2019 at 3:02pm

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
Hi Gary - My work on the Marcoux Bromberg is an effort to fulfill my commitment to Rudy Profant and build a scale model of his airplane. As was mentioned in one of my earlier posts, Rudy has  passed away and his airplane is in the New England Air Museum in the condition he left it at the end. I feel this strong urge to do this and the original concept was a desk top model with appropriate detail and color to represent his airplane. This urge has grown over time to this point and the airplane will be finished in as much scale as I can muster. My skills have improved substantially over the past two years and working in this mode gives me a chance to go a bit slower and make a bit more realistic model. I was always measuring myself against the other builders, believing, wrongly, I should be able to "keep up". This venue we have chosen is exactly where I want to be in my modeling activities as it gives me an opportunity to try various methods and materials and also returns me to my drawing board - home sweet home. So there will be inordinate amounts of time devoted to this enterprise and any money spent will be fairly modest as this project is put together with many standard techniques and wood available at the local hobby shop. There will be some unusual materials, i.e. am looking for sub-miniature piano hinges that when open will measure approximately 1/8 to 5/32 inch wide. I have had many emails from friends and others with links to various doll house manufacturers but their material is also too wide. May have to find a way to make my own and this is what makes this effort and others like it so rewarding.

On to your problem, I left you a fairly long reply on your P51 post as to my thoughts that may be some hindrances to your success. I'm still rolling this issue around in my head and believe the answer is fairly simple. My methodology is to think about it for a while, stop thinking about it and the answer shows up in places and times least suspected. My only other driving force is a comment made to me by a friend some time back that says "if you are not prepared to be wrong, you will never be original".

Talk soon.
Mike
 

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #22 - Jan 9th, 2019 at 9:56pm

Skyediamonds   Offline
Global Moderator
Enjoying life and all
aspects of modeling
Reno, Nevada

Posts: 2365
****
 
Mike;

From what you'v described in your attempts to replicate in model form the inner workings of the wing just as the real ribs on the racer, and spending enormous amounts of time and money, sounds like you and I have bonded in this hobby....  Smiley

I'm also at the point where after numerous variations of attempts to pin wash panel lines onto glossy paper, plastic and other materials using paints, clear gloss paints, floor polish, primers, and thinners all in various combinations without any success whatsoever, I can safely say at this point that I'm moving on with using fine point marking pens to simulate the paneling of the wings. 

So, in this regards to our excellent hobby, you're not alone.

I agree with Tom in trying out the Word program in effort to not save money, but also in having greater control over what you're trying to replicate in modeling scale of the real article.  You sure have my attention and admiration.

Gary
 
IP Logged
 
Reply #21 - Jan 9th, 2019 at 11:30am

Sky9pilot   Offline
Administrator
Stick & Tissue
Kelso, WA 98626 USA

Posts: 10266
*****
 
Mike,
If you have a printer scanner all in one you could scan the root rib and save it as a "jpg" file and then insert it into MSWord doc.  You can then drag the corner of the picture to what ever size you want and copy it several times on one page to experiment with size.  Just add the rulers(in msword) to the edges of the screen to get the size you want. By dragging the corners the dimension of the picture stay in the proper relation to each other...  Lots cheaper than paying for the copier time at the store.
Tom
 

If God is your Co-pilot...switch seats...
Your attitude will determine your altitude!- John Maxwell
And ye shall know the truth, and the truth shall set you free. Jn 8:32
IP Logged
 
Reply #20 - Jan 9th, 2019 at 8:47am

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
Gary - I thought of doing that but since I'm shooting for a more realistic rendition of the airplane including the internal workings of the wings, etc. I'm going to go ahead with the layout of the ribs with the intention of creating the ribs in their actual form. This means defining the outline according to the airfoil ordinates I have and is described in the documentation. To that end I did take the root rib to the printer and tried reducing the rib by a percentage to make the other ribs. While this worked to a certain degree the reduction changed some other things and as expected, the spar thickness and height and the reduction also introduced some distortion. I also wasted quite a bit of time and some money on the numerous attempts at reaching the correct rib size for each rib so back to the drawing board. The layouts are not difficult just time consuming and since this is looking like a long term project, why not go for it. The layouts should be done in a couple of days. The spars are defined and I can start working on them but still need to define the retract gear mounting points and their configurations, define the scarf joint reinforcing plate sizes and shapes and define the mounting hardware so I can get to the hobby shop in a few days to start accumulating the hardware and looking for structural shapes for the landing gear mounts. Before I can commit to the ribs, the aileron torque tube arrangement and the flap actuating mechanism needs to be figured out since it all involves the ribs and their internal design. Fun project and I feel like I'm designing the plane as did Marcoux and Bromberg originally.
Mike
 

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #19 - Jan 8th, 2019 at 10:18pm

Skyediamonds   Offline
Global Moderator
Enjoying life and all
aspects of modeling
Reno, Nevada

Posts: 2365
****
 
Since it appears that all the ribs are of the same airfoil, I once read an article that really simplifies the reduction process from root rib to the wingtip ribs. 

Simply stack a set of balsa rib blanks on top of each other with the root at the bottom and the tip at the top.  To start, just stick on the bottom blank (facing outward) a piece of paper that has the airfoil of the rib root outline.  On the top blank, stick another piece of paper that has the outline of the rib at the wingtip.  The blanks could be pre-cut like succeeding smaller rectangular shapes.

Start at the leading and trailing edges and cut away the stack of blanks until you have a set of rectangular shaped blanks that, more or less, resembles an Aztec Pyramid with a wide base and a small "peak."  From there, its just a matter of using a coping saw or similar cutting machine to trace out the ribs, carefully following the outlines on the papers stuck on the sides.  You could also use a file, until the whole stack matches up the outlines of the two pieces of paper at the ends.  Then fine-tune it with a touch of sand paper.

The number of ribs will determine their exact size in relation to their location.

This way, you can skip the paper outlines of each rib altogether.

Jes' sayin......   Grin
 
IP Logged
 
Reply #18 - Jan 7th, 2019 at 12:18pm

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
Neal and Gary - Thanks for dropping in and feel free to drop in any time. Started work on the wing layout this morning and just traced the outline so as not to have to reproduce it from scratch. The drawings by W. F. Kerka (his last revision was in August 1980) are very complete as to general arrangement and a web search gave me more data regarding the spars and the material therein and development data to validate the diameter of the cowl in my drawings, spot on. The root rib layout has been started and will finish this afternoon. Am hoping to be able to reduce the root rib to the other sizes in the wing at the copy center. This needs to work otherwise there are 9 more ribs to lay out manually. Will know soon.
Mike
« Last Edit: Jan 7th, 2019 at 2:24pm by New Builder »  

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #17 - Jan 7th, 2019 at 11:02am

Skyediamonds   Offline
Global Moderator
Enjoying life and all
aspects of modeling
Reno, Nevada

Posts: 2365
****
 
I agree with Neil, go for it.  If you need any suggestions, we'll be here.  Other than that, we'll just sit quietly looking over your shoulder.

Gary (Skye)
 
IP Logged
 
Reply #16 - Jan 6th, 2019 at 10:17am

Kerak   Offline
Senior Member
I Love YaBB 2.5 AE!
Roy, Utah

Posts: 1855
****
 
Go for it, Mike!  Start cuttin'!  Smiley

Neal
 
IP Logged
 
Reply #15 - Jan 5th, 2019 at 9:14am

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
I'm back on the Marcoux Bromberg racer and have started from scratch since I started this with the wrong attitude and a more simplistic approach. I was intending to just make it a "good to look at" model without a great deal of detail in an effort to make my commitment but as I got in to the details I decided to move away for a while. I'm now approaching this with a more sincere motive and far greater detail. So to that end all the documentation and paperwork have been recycled and all balsa committed to the project has been reclaimed and as mentioned before, the wood is in the wing of my Interstate Cadet. The documentation for this project has been enlarged to a 1/12 scale (1" = 1'). Since there is not a great deal of design documentation available, I will use some more common design methods for the wing ribs and will stick very close to the available information on the drawings and the model will be representative of the last modification to the airplane in 1938. This is the version purchased by Rudy Profant and modified further by him. His modifications did not add any great difference in the plane but he did change the color from a cream color finish to the current yellow fuselage and black wings. So with all the being said, I have completely cleared my building area, cleared the drawing board, vacuumed the floor (made my wife happy), added some storage area for all the new toys I managed to accumulate and sanded my mag board to remove all the bumps and stray glue bits of glue and dope. So, this is the new beginning and I will stay on course to the end. There will be a lot of design work  but with no more outside distractions, should be a fun build.
Mike
 

Overall_Page_1.JPG (1843 KB | 14 )
Overall_Page_1.JPG
Overall_Page_2.JPG (1823 KB | 8 )
Overall_Page_2.JPG
Wing_and_Airfoil.JPG (1949 KB | 13 )
Wing_and_Airfoil.JPG

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #14 - May 20th, 2018 at 7:10am

New Builder   Offline
Senior Member
Amherstburg, Ontario, Canada

Posts: 847
****
 
Greetings all - The rudder and horiz stab were built using the typical stick and tissue method then the 1/32 sheeting was applied as Tom mentioned. His caution is well placed as the reactivation of the glue is permanent and tight, as I have heard say "bark on tree tight" and no going back. The wing has been completely rethought and I took it apart and used the material in my Interstate Cadet wing. The reason was that I was intending to use two spars spaced at the sheeting width I didn't allow for the reduction in rib length as it neared the tip and completely changed the airfoil and I was using a leading edge that was too thick and too tall, too much carving. The new wing will use ribs sliced along the chord line and built in two pieces allowing the rib to be flat on the building surface to add the portion of the leading and trailing edge and two spars, then take that assembly up and add the bottom of the airfoil and the lower spars. The chord line exits slightly below the trailing edge so no need to add any more material there. That and I have a very small building area and the wing was taking up too much room on my drawing board. I'll finish the Cadet and get to the Marcoux Bromberg very soon as it is quite important to me.
Mike
 

Have no fear of perfection - you'll never reach it. (Salvador Dali 1904 - 1989)
IP Logged
 
Reply #13 - May 19th, 2018 at 6:31pm

Sky9pilot   Offline
Administrator
Stick & Tissue
Kelso, WA 98626 USA

Posts: 10266
*****
 
I believe the tabs are so the wing can be built flat on the table till it's ready to add dihedral. 

As far as the heat treatment on the sheet balsa you'll need to add glue to the bottom of the sheet marking out the areas that will touch the L.E. and T.E. and the ribs and apply glue to that area only allowing it to dry completely.  The heat from the iron will polymerize the glue on both surfaces and lock them together.  Just make sure you have everything aligned correctly before applying heat.  You'll have to experiment on getting the heat hot enough without too hot!

Make the sheeting a bit oversized.  And trim it at the L.E. and T.E. after the heat is applied and the sheet is attached.
Tom
 

If God is your Co-pilot...switch seats...
Your attitude will determine your altitude!- John Maxwell
And ye shall know the truth, and the truth shall set you free. Jn 8:32
IP Logged
 
Pages: 1 2 3 4 
Send Topic Print