Fiddlers Green

Hi people!

Aaron send me for a test one of the new models, a Curtiss A-12 Shrke. So I intent share a my buid log in (close) real time. I believe is usefull and I show my techniques to build in 1/100 scale.

The first post is a aviation story.

The Model 60 or A-12, was a superlative development of Curtiss A-8, among the biggest differences besides a complete redesign of the canopy, is the adoption of a radial engine to replace the heavy and complicated Curtiss Conqueror inline engine of A-8. The predilection for radial engines by the U.S. military primarily for attack aircraft, was justified by the small size (harder to be hit by anti-aircraft fire) and have a much simpler system cooling.



The new version was called the A-12. Had a little more success and a production slightly larger than the previous version. But it was soon supplanted by other more modern aircraft and a change in the mindset of the strategic USAAC who preferred to attack profile twin-engine aircraft



A small batch was sent to the Chinese Nationalists in 1936, were used in the attack profile, achieving some successes against the Japanese naval aviation as fighter vectors. However, in its original function as attack aircraft, the Shrike proved slow and vulnerable if revealing a failure. The Koumitang Air Force just relegating them to training.



In the U.S. A-12 was never used in combat, although several of them were stationed at Wheeler Field in Hawaii at the time of the Pearl Harbor attack. The last were withdrawn from service in 1942.



Continue (after launch)

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Cosmo Tigers Go!

Considerations before building... (sorry for my english)

For the builds in 1/100 scale I use "bond" paper 120gsm in general this paper absorbs the ink well on inkjet prints, have good traction mechanics, preventing the breakdown of fibers when making folds or conformations in parts of model . It's cheap and easy to find in supermarkets, large bookstores, and papershops. This paper called to aka sulfite, filiset. I not know the names in USA and anothers countries, in Brazil is a Sulfite.



Eventually I use the same paper but in another havy thickness (180 and 240 gsm) for laminations and anohter special tasks...

To prepare the pieces, use only in cutting sharp scalpes. One is the Olfa No. 15 for curved parts, a surgical scalpel # 11 for straight cuts and chinese olfa (aka Xing Ling, I buy in one dollar shop in Brasilz is called 1,99 shop) that mimics the OLFA for sequential and repetitive cuts (like the glue flaps). I paint the edges white with artistic pens or watercolors.
To form the parts, I use form sculpting tools, needles, metal rods, tweezers and all the pieces are press palm or on top of a rubber. Larger parts like wings are press sound in soft surfaces such as the top of the leg, or on top of a magazine.






For gluing after much attenpts and errors, I use three types of adhesives: glycerin stick glue for lage areas, styrofoan glue and a special white glue to made scrapbook. Eventually for gluing different materials I use CA glue in gel form.



I use to apply cement a spataula or hypodermic needle...

Reducing scale: All betas from Oddball not have a determinated scale but Aaron made all kits in 1/48, 32 or 22/24 scale (depend of size) for bigger planes (1/70/90/120). I print a drawning in 1/100 scale of subject and determinated the size of wing, and another area (like stabilizer or rudder) and use a software to made a convertion. Or I build a wing in original scale and made a wingspam found the scale, if you not have a scale calculator soft (exist many free in WWW) is a easy formula to determinate the scaling factor I use in some times. Before WSAM calculator I use the metthod:

Scales are ratios of measures in like units: 1/72 is 1 inch on the model = 72 inches on the full-sized original (or 1 centimeter, furlong, or parsec on model to 72 of same at full size).

The desired scale is then the existing scale times some unknown percentage or fraction, i.e. the conversion factor (either enlargement or reduction):

1. DesiredScale = ExistingScale * ConversionFactor

2. Therefore, to find the conversion factor, we regroup and divide to get the universal scale conversion formula:

ConversionFactor = DesiredScale / ExistingScale

Example: to convert 1/72 to 1/48

ConversionFactor = 1/48 / 1/72 = 72 / 48 = 1.5 = 150%

A 6-ft (72-inch) pilot figure is thus 1-in tall in 1/72 scale and 1.5-in tall in 1/48 scale.

Advantages of the formula: You can always figure out the intermediate ratios correctly when using photocpier enlargement. In the above example, most copiers would not do the full 150% in one pass. Most copiers max out at 121% or 141%. I have seen almost every other possible figure too. So having a chart of common scale conversions is not likely to be all that useful in many cases. Using the formula, you just figure out what the scale will be after the 121% enlagement:

IntermediateScale = ( ExistingScale * .121) + ExistingScale.

Then you use IntermediateScale as the ExistingScale in the formula.

After the conversion I made the reduction in my PDF program. The scale of A-12 is 1/32 to 1/100, the reducton factor is 32%. So i start the print sheets in my Epson L200 Bulk Ink in high quality photographic mode...

Continue

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Cosmo Tigers Go!

Going to the actual assembly, started composing by cutting the fuselage to the wing root and cockpit formers.

Despite the designer does not like these formers that simulated the rear walls of the cockpit are widely needed as they help to give a rather peculiar A-12 fuselage.



I paint all white edges with blue watercolor...



I gluing all fuse segments...



I started by assembling the fuselage center section because of the formers, these in turn were not laminated. I used the double feature of the part itself. Two building approaches can be applied here: The first is that it is more complicated cement formers in the wing root, in positions that are already marked and from there to glueing the central segments of the fuselage, and then glue the fuselage in the two central segments, open holes, insert the wing root and then enter the formers. I opted for the second possibility seemed easier and got success.





After dry. I glue the other fuselage segments.





Continue soon...

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Cosmo Tigers Go!

This will be interesting to watch.

Beard

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More Scotch and stogies for my wingman!

Thank's Burning.

Go to resume my build.

In this section I prepared alar surfaces our friend. Initially built the supports of wings that already provide regulation for the correct dihedral.



Later, I cut and prepared wings, rudders and stabilizers, creasing glue tabs and painting the white edges with yellow.



I started by gluing the wings, they were fixed with Styrofoam glue because it does not cause deformation of the paper in large areas of glue...



I mounted the tail smoothly. Note that the edges of both wings as the tail are not glued yet, it serves to regulate if necessary chord of wings, after all I did set gluing the ends.



Verified correct alignment sealed the wing tips and tail ...







In the next update, wings roots and spats...

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Cosmo Tigers Go!

She's coming along nicely! I really appreciate the behind-the-scenes look at your building process.

Thank's Willygoat

I made the seats the pilot and gunner are simple pieces that help distort the interior, which is a recipe for adding a nice add-on the choice of modeler.





Gluing in the places



In this section also treated a delicate topic: the roots of all alar surfaces. Although they are simple pieces they demand werent careful when pasting as it needs to be well resolved, on penalty of being large cracks or misalignment surfaces.



Started with the roots of the wings, usually lap gradually starting from the bottom. It is a delicate task requiring patience, in some cases other objects and uses needles to maintain the height of the rope at the time of bonding, as is the case in this photograph below ...



After a few hours of drying, we did the same procedure with the roots of stabilizers ...





It is extremely important to use a little part of glue in this type of assembly.





Subsequently manufacture the root rudder...





The results at the moment...





Until the next update

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Cosmo Tigers Go!

Well friends, we resumed the assembly with the construction of the pants of our "comrade", are simple parts that need to be bent and glued and give a special charm to the whole model.



Note that in parts such bonding should always start with one end ...



Tail wheel carenage



Wheels...



Here the set of fairings mounted with .50 ranging in pants, I ended up forgetting to photograph this step, but it is simple as you can see in the photos ...





Finalizing this assembly step, we set off for the details in pants, which consist of supporting arms and points of fly cables.







I use a needle to give shape to the curved shape of this type of piece.





Here we see the same installed, it is interesting to see documentation to see if they are exactly in the right place.






Continue

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Cosmo Tigers Go!

I left for a small step which is to put a lot of detail on the fuselage, and the rear canopy.



We started preparing the part of the rear canopy, the bending over a rubber.



Note that the glue area is small, then prepared to assist the tabs internal fitting and gluing the fuselage ...





See how this simple measure improves construction.



An overview of the model so far.

Then prepare the mounts of wings, are small parts, notice that the edges were folded with tweezers ...





I cut the windshield and small engine cowlings ...



After the mounts of wings dry, glued in the areas indicated by the starting point of the fuselage, leaving it dry and then gluing the wings ...



I took while drying and mounted the fairing and windshield.



I glued the windshield starting at the center of the piece and then the sides and then the parts of the air intake / engine oil.





Aaron provides a machine gun for the tail gunner, but unlike the A-8, to keep the clean lines of this Shrike opted not to use this construction.



General aspects. The model is 75% ready ...

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Cosmo Tigers Go!

I like the idea of you using the fuselage formers to give the shape to the body. I wish more models/designers had these formers in their builds. I'm a real big fan of easier. You’re doing a top notch job on this model and I am looking forward to see how it comes out. Aaron is an artist isn’t he? I really enjoy his models and what he is capable of doing with paper. The other item I really enjoy is now that he a part of FG. This is a great add to our family. Thank you for sharing your build with us and you’re doing an incredible job on this aircraft. wc

Thank Wad.

Aaron really is a brilliant designer, their models have a huge quality combined with unprecedented simplicity. I can say this with propriety, because I have in my collection over twenty models it built. I know that Aaron does not like to formers in their designs, in this case it was necessary because of the very particular format with compound curves in the center of the fuselage.

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Cosmo Tigers Go!

The Shrike looks amazing! It seems like Murph went crazy with the extra add-on details with this one, but they really make it pop.

Thank's Willigoat

Time to update the build log.

Going to the final assembly, we treat a sensitive part, the cyclone engine, which in this case is very well represented, started cutting all the pieces that make up the same, including the cylinders with their covers, the gearbox and the block .



We started with the assembly of cylinders which have a characteristic way, is a repetitive work and why not to say tedious but worth it ...







The finish engine...



We then began to ride the cownling a sensitive part consists of several cones and truncated semicones, started from the back. going to the "equator" of the piece is the larger ring. Very careful alignment of the numerals on the side.





Attached are installed and the engine then pasting the last ring cownling.



The model almost finished ...









The escape assembly



Continue

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Cosmo Tigers Go!

That's a great looking engine. I could see myself struggling with the cylinders at full scale. I can't imagine them at this scale. Well done!

Thank's Willy, yes is a tedious work but the result is very nice. Goal to design skills from Aaron.

Now preparing the final details of our model, focusing initially on the rigging which is quite simple and focuses primarily on the wings.

For those not familiar with my builds, the material I use to simulate surgical ligature wires is a fairly thin steel that is sold straight to install cut the thread in the right measure, obtained with a compass transfer, the segment is labeled with an electronic tool (used to remove components) and cut with nail scissors.



Observing the documentation available, I started installing the cables, being stuck with a small drop of CA glue gel.



Up..



Bottom...

With a small piece of Vivaldi paper , (pulp colored in black color) I fabricated separators cables. This is a custom detail, but it gives enough life to the model.



With the help of a small clamp, installed with CA glue separators, again referring to my documentation, the secret and build the strips with larger size and then go cutting with scissors properly in correct sizes.





Finally I build the antenna mast and installed radio cables.





Last parts: those that make up the propeller, easy to assemble without the aid of templates because there is the hub, the marking where gluing position.



A good UV varnish layer and is ready..



Next post: finished model

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Cosmo Tigers Go!