1/32 IMCTH A6M2b Zero Type 21 Fine Structure
By John Smith
For those of you not familiar with IMCTH or with the terminology “Fine Structure” as it is used in the model airplane industry, a bit of explanation. This is a “skeleton” kit; all of the framework and guts of the aircraft without the exterior skin. I built another of these kits last fall, a 1/32 P-51D Mustang, just after Ross completed his build of the same for one of the team builds, and you can find it in the Air Gallery.
In terms of building a model, it certainly is different. There is nothing injection molded about this kit. The majority of the parts are stainless steel PE, a substantial number of white metal pieces, and some bits of aluminum rod, “rubber” tires, and a vacform canopy, complete with some adhesive chrome framework.
The P-51 I build was challenging and a lot of fun, and it really produces a unique model. I’m hoping to have a similar experience with this kit. On the P-51, I painted a lot of the interior parts to give some “kick” to the innards rather than having the entire model be a monotone aluminum color; I’m planning to do the same on this kit. In addition, I will shortly be beginning the Tamiya 1/32 Zero Type 21 to display next to this skeleton model.
By the way, IMCTH is issuing a kit in the same format and scale of the Bf 109 F-4 sometime in the next 30-60 days. I already have mine on pre-order from hlj.com , which is the only place I know of to buy one of these kits should you so desire.
So, with that, let’s get started. Following this text are some photos of the “box art”, the PE part sheets, the bags of white metal components, a detail view of one of the bags, and what passes for one of the instruction sheets (there is no instruction book) on this model.
Next time, I’ll talk about which tools you really need to have, adhesives, and some of the processes involved in putting together one of these beauties. If you have any questions you would like to ask me directly, feel free to PM me or just post it here on the build log.
Hope you enjoy it!)
Well, here we go….
I’m going to do this first post as a kind of tutorial on what you need to know about these Fine Structure kits to build one successfully, so if you have no interest in that, just skip this post and go on to my next one. So, I’m going to spend some time discussing things like adhesives, tools, some techniques, and how the parts and instructions are organized so that if you buy one of these you won’t open it and be terminally confused from the first moment.
This will be the major area of difference between these kits and injection molded: the adhesives. Everything else is still pretty much the same, you will have to separate parts from their trees, or nubs, test fit, file or sand, test fit again, and finally glue it in place. The other major difference is that in this kit, you won’t be painting anything unless you choose to, like me. I will be painting the cockpit, engine, fuel tanks and so forth to make them stand out a little better agains the mono thematic aluminum kit. So, since you are primarily gluing metal to metal, you will be using CA. I recommend 3 viscosities, thin, medium, and gel. I also strongly suggest the use of tools for applying the CA as well as palettes or tiny cups like the red ones shown into which you can decant some CA and then transfer it to the model using a tool. DO NOT use the CA directly from it’s bottle or tube. You will only end up with a mess the likes of which no one would want to deal with. Micro Mark and Radu Brinzan carry some nice tools for applying CA and when they get clogged, but just burn off the dried excess with a match. Some people prefer to use a toothpick, which is my tool of choice for gel CA, but for the thin and medium stuff, I really recommend you get some application tools. You’ll also want some accelerator because most of these joints are fiddly and holding it in place simply won’t be an option. I recommend you use a micro brush, like I show in the photo, to apply your accelerator. Soon, you will be applying CA and dabbing it with accelerator in a 2 handed motion and you will finish your model in no time!. CA debonder is your Friend! It will enable you to make egregious mistakes and fix them before anyone knows about them. That will be your real problem, not stuck fingers. I strongly recommend the CMK debonder product. I’ve used several and I think the CMK product is especially aggressive and effective leaving very little, if any, residue behind. By the way, your tool of choice for using debonder will be the micro brushes as well, so stock up on them. They can be procured relatively inexpensively if you look for them as a dental tool, rather than a hobby micro brush.
I have to restrain myself here because I could talk about tools for hours, so I’ll be brief. I can tell you what you WON’T need; you won’t need to buy one of those fancy PE “hold it and fold it tools” that seem to come in all shapes and sizes these days. Everything you need to bend can be done with the bull nose flat pliers and the micro pliers shown in the photo. It goes without saying that you will need PE shears like the blue Xuron ones I have pictured here. But, you will also need the Fiskars Micro Tip shears shown as well. The reason is that the stainless steel PE in these kits can be very, very thick, and you will need a tool with some authority to cut it. Sanding sticks, micro needle files, or both, can be used to file the “nub”s you leave behind when you cut PE with the shears. I prefer the diamond micro needle files…. They last a lot longer and do a finer job. You will also be trimming and filing white metal parts, too, so I would save some money and get the better diamond coated files right from the start rather than going through a lot of sanding sticks. It goes without saying that you will also need tweezers, hobby knives, and clamps during your build.
OK, yes, these are my binocular viewers. Unless you have very, very keen close vision, you will need a set of these. Do yourself a favor and get a good set that will last you a lifetime and have high quality optics like “Optivisor”. I’ve tried to go the cheap route and they have all ended up in the trash bin, take good care of your eyes and get something of this quality. It will make all the difference in your build.
Here is the first of the parts sheets; this one has all the PE parts on it as well as the lines you will cut from kit supplied wire. You will spend a lot of time identifying parts from these sheets, believe me, so I decided to include them in this primer so you could get a taste of the complexity of the kit and the numbers of parts involved.
This second sheet covers white metal parts, and you will really use it. It’s amazing how similar white metal parts look when they are in those little plastic bags. If you think I’m overstating that, just have a look at the drawings of I1-I5 and see what you think.
This is the final white metal sheet, and it also includes some miscellaneous parts like the canopy and the rubber tires, etc.
This is the Instruction Overview sheet. Somewhere in this mix of Asian and Western characters and pictures, you will be able to find an explanation for every little symbol you will come across in the actual instruction sheets (48 of them!). I ended up referring back to this sheet and puzzling over it often, but it always lead me in the right direction on what to do.
Page 1 of the actual instructions ……… Look a little different? Yup, they do. It will make more sense shortly. I’m going to go through a couple of sections and explain it, but there is really nothing here that you wouldn’t be able to find on the Overview sheet. You can probably also visualize yourself grabbing for the parts sheet at this point to identify these first parts.
So, here is Part 1 of Page 1. And here is what they are telling us to do:
1. Drill (14) 0.5mm holes in each of parts I1 and I4 at the locations indicated in the drawing.
2. Drill (7) 0.5mm x 0.3mm holes in each of parts I9 and I10 at the locations indicated on the drawing. (the depth is not critical; just don’t drill through)
This type of step is pretty common for these kits where you have to enlarge or deepen holes in white metal pieces because of the limitations of the white metal molding process. The hole sizes are typically 0.5 mm or 1.0 mm, so don’t go out and invest in a big set of tiny metric drills.
See, once you get the hang of it, it’s not that tough to figure out. But, we will cover one more step.
OK, this is a little complicated, but just follow with me and it will become clear. The good news is that we are going to install all of the ignition wiring in the Type 12 engine….. Cool!! I know on the P-51 I built, the level of detail and accuracy rivaled the Tamiya kit and I’m expecting the same from this Zeke.
1. Cut 28 pieces of wire each 11 mm long from the 2 pieces of 0.4mm x 170mm wires supplied with the kit
2. Cut 2 pieces of wire each 25 mm long from the single piece of 0.4mm x 145mm wire supplied with the kit
3. Cut 4 pieces of wire each 8 mm long from the same single piece of wire that you used in Step 2.
Ok, let’s start building.
First up in the instructions is the engine. That seems like a good place to start.
Initially, use the parts guide and the assembly instructions to identify which parts you will need, get them out, and I highly recommend putting them on a sheet of paper or paper towel on your work bench labeled by part number. Some of these parts are very similar to each other so it’s important to keep them organized. Remember, in this kit, the only thing on a “sprue” accompanied by a part number are the PE parts. The white metal parts (with a few exceptions) have no part numbers on them, so it’s very important to keep track of them yourself.
Since I’m planning on painting my engine to make it stand out, priming with a good self-etching metal primer is a must. If you try to prime these white metal parts with hobby primer you will only end up with peeling paint. Rustoleum, Krylon, Duplicolor all make essentially the same product so take your pick. Like most overall paint jobs it’s a two part process, fasten one side down to a cardboard (it’s what I use) with tape, prime it, let it dry overnight, flip it over, tape it again, and prime the other side.
Here is the result and you can see how I have organized the parts.
Next up is to drill out the crankcase parts and cylinder heads for the pushrods….. (When I did this initial write up, I thought they were ignition wires….WRONG!!). Since there are a total of 14 cylinders in the Sakae Type 12 engine, you will need to drill two holes in each of the crankcase parts and two holes in each of the cylinder heads to fit the pushrods for a total of 56 holes. Don’t worry, there is a “dimple” at each location to be drilled and the holes don’t need to be more than .5 mm deep (at the most!), just enough to glue a pushrod in place. I used a .5 mm drill (as called for instructions) and a machinist’s pin vise to drill these holes. It’s white metal so it’s pretty soft, the drill doesn’t wander because it has a locating ‘dimple’ to start in, and all of the locations are highly visible, both in the instructions and on the parts themselves. It’s tedious work, but not difficult. I just turn up the music and take my time. After all, it’s the ‘journey’, not how fast or easy it is that matters, right?
Here’s the section of the instructions detailing the location of the holes to be drilled (arrows), and the parts and tools (I included a #11 Xacto blade for scale).
Finally, for this posting, I cut the pushrod wires as called for in the instructions (shown and described in detail in a previous post) and organized them into small trays labeled with their step number and size. I find the little plastic palette trays to be very useful for keep track of parts and small assemblies.
One important point here: the instructions tell you to break the piano wire used here by bending it back and forth with pliers (???!!!). I have no idea why they say that, but it’s a stupid way to do it. Use diagonal cutters and it’s a very quick and easy job. There is plenty of piano wire, so you won’t run short.
Next, I’m going to paint the engine parts (it’s easier to do them separately than to paint the assembly because of the way this kit is structured) and then install the first row of cylinders and pushrods.
See you next time!!
P.S. It’s hard to find information on the correct colors for this engine on the web… I searched without much success. So, since I am building the Tamiya 1/32 kit at roughly the same time as this, I’m using their color specifications. (I’m planning to do a display of the two Zeros like I did with the P-51 kits.) I think Tamiya is usually a reliable source (But I hate having to do all the mixing!!!) And, I will be starting a build log on that kit in the WIP section of the forum.
Thanks for reading and Happy Modeling!