Building the 1/72 IRMA Kit No. 2©SM®TM the Shenyang JJ-1

At last our second kit has been released! Like the first, it has been molded in a very efficient way and does have some unique features. When the kits are packed for shipping you will receive the parts in a sealed, plastic bag, instructions, decals, a certificate of authenticity, brief background of the aircraft, along with a safety recommendations disclaimer.

Parts are pretty much attached to the casting blocks for the smaller parts and you will need to remove some resin from the bigger parts. We recommend a microsaw which you can get at your local hobby shop or on-line. As always, when working with resin, use a dust mask and where possible wet-sanding is best to avoid the resin dust.

Here are the parts after clean up which involved separation from the casting blocks via microsaw, trimming any excess resin with a hobby knife, sanding off the edges and making the surfaces smooth with sand paper and a file. Next the canopy is carefully cut from the vacuform plastic with a hobby knife with the edges sanded even and smooth. After this each of the parts are test fitted and trimmed as needed. So now we can begin to build the model!

Due to the recent computer disaster at IRMA©SM®TM, this article is just a beginning and will progress as the kit is advanced. Please bear with us this week and next as we continue recovering our data and files. There will be more photos, drawings and recommendations in the coming days.

To start the kit, first check all of the parts list to verify everything is there. For this kit the fuselage was the starting point (piece 13) to which the rear body (piece 25) was attached followed by the wing central junction (piece 14). Once these are joined together you have a basis to expand from.

For the wings (parts 15 identical) insert the main landing gear closing wall (parts 24) as they are. Prior to this you may wish to sand the lower portion to eliminate the indentation as there was none in the landing gear doors (see relevant photo) or you can grind it smooth after inserting the closing walls (this was the approach of the kit maker). Once completed, sand the top of the wing smooth.

Fasten the completed wings to the fuselage making sure the angles match the drawings at the top of the instruction sheet. Next attach the tail fin (piece 27) making sure it lines up with the fuselage and tail bumper below. This is a good point to also attach the rudder (piece 28) and tail end fairing (piece 32) making sure they are lined up with the angel of the drawing. The jet exhaust (piece 34) can also be inserted at this point.

After this the left and right tail planes can be attached (pieces 29 identical) with the left and right elevators (pieces 31 identical). Again, make sure to line up with the drawing.

At this point construction of the cockpit tub can be started. Attach the control panels (pieces 8) to the front and middle of the tub with the seats (parts 7) just behind the holes in the floor. Next comes the nose (piece 1) which will need a floor for the front landing gear. This can be made from a piece of sheet plastic or resin. It needs to be 5 x 15 mm. Put this in place then insert the appropriate amount of weight in the front of the nose to prevent tail sitting.

Now line the cockpit tub with the front of the nose and glue in place. Next join the nose to the fuselage (part 13). Once lined up the air intakes can be constructed. First place the inner intake walls (piece 11) into each air intake (part 10) then fasten these either side of the cockpit.

Once complete assembly is dried, the landing gear can be built. Start with placing the main landing gear legs (parts 18 and 19) in the wheel wells. Make sure the tires are facing inside. Then file the indentation off of the main landing gear doors (parts 23) or add filler with resin or plastic card. If desired new doors can be cut from plastic card. Refer to the MiG-15 UTI drawing for placement of the main doors. Next apply the upper parts of the main gear doors, however, unlike the MiG-15 UTI, the JJ-1 doors will line up with the main doors at the correct angle (see photos). Now you can dry fit the main landing gear wheels (parts 21) to check alignment.

For the front landing gear glue the main assembly (part 9) to the rear edge of the opening closest to the cockpit tub. You will need to construct two doors. The JJ-1 was unusual in having two different door halves. For the left door the dimensions are 4 x 13 mm for a simple rectangle. The right door is a bit more complicated in that it has a "box" at the end. For this door the dimensions are 15 x 4 mm for the top, however, at the end the door drops down 3 mm and the box portion is 3 x 7 mm. Again, check for alignment.

For the canopy, cut very carefully with a sharp hobby knife from the vacuform sheet. Sand to line up with fuselage then construct the pilots mirror from scrap resin and attach with white glue to canopy using the drawings as reference. Test fit for accuracy.

The VHF aerial is also constructed from resin 9 mm with the radio aerial being cut from piano wire. Note that this aerial goes 6 mm from the top of the tail fin. For added security the end can be drilled into the tail fin then secured to the VHF aerial. The pitot tube on the left wing can be cut from a thin wire or straight pin 15 mm long. Again the end can be drilled into the wing before securing.

For the 23 mm canon 3 mm copper tubing was used being cut 6 mm long then inserted through a drilled hole in the left side of the nose. Next a 10 mm piece of 1 mm wire was used to create the inner barrel. For those sticklers of detail, a hollow needle can also be used. Just be sure to dull the end!

For painting the completed model only three or four colors will be needed for the flying prototypes. Overall the flying aircraft was dull aluminum as was the cockpit interior. Control panels, seats, landing gear and wheel wells were black, as were the tires. Pilot uniforms were also black, including belts. Pilots faces are flesh. The only other color for this version will be a rubber variation for the tires if desired.

For the version in the Chinese Aviation Museum overall flat white with flat red details would cover the exterior with the rest being as stated above. IRMA will be coming out with a set of decals for the white version later in the year.

Below is the completed model as the flying prototype known as "red 101" as flown. All three aircraft survive today in museums.

The International Resin Modellers Association wishes to express our continuing gratitude to Dr. Bushi Cheng, one of the original designers of the Hong Zhuan-503/Shenyang JJ-1, now retired, of the Shenyang Aircraft Institute. It is extremely rare to have consultation with an Aerospace Engineer from the dawn of the jet-age and even more unique to have an invitation accepted to work on a kit of the actual aircraft. We at IRMA indeed feel blessed and this makes this particular kit at this time a most intriguing subject. Our sincerest "Thanks!" Dr. Cheng!

- Zane R Nobbs, International Resin Modellers Association©SM®TM, Copyright 2010

Photographs, illustrations and model by Zane R Nobbs

All text, photos and illustrations copyright © IRMA 2010