TAMIYA'S 1:16 PANTHER AUSF. G KIT
09/04/09-- It's a troubling sign when you buy four RC tanks in the space of three months, despite the wise side of your brain warning you not to. All it takes is ignoring that warning light for as long as it takes to press a button on your browser and then, whoops! Too late! And that's pretty much how it happened. The button was pressed on a Wednesday morning and thanks to Tomas of VQ Warbirds, by Thursday afternoon, Fedex was knocking at my door with a huge package. That wasn't nearly enough time to wallow in the regret of what I'd done, so I skipped that part. Wowwwww... kewl!!! I wasn't even fazed when I heard, a day later, that Heng Long would be shipping their new (and likely much cheaper) Panther G at the end of the month. Well, this is my last one. Seriously.
Because I've done this enough times before, I knew the drill: I ordered what I thought I needed at the same time, without any indecisive, time-wasting pussy-footing around! In fact, even before ordering the Panther, I had an extra Impact Battle Unit, an extra pair of Graupner Speed 400 motors, an extra Turnigy Speed Controller, 2 extra Pico Switches, a spare Spektrum BR6000 receiver and even a Verlinden 4-man Panzer Crew. Wow, how'd that happen? It looks like smart, time-savings planning-ahead, but it's really just what happens when you buy spares and buy stuff for a project that didn't need them. If I'd been truly prescient, I would have already had this stuff on hand and might have shaved a week or two off the build:
This time, I decided to explore photo-etched detailing. It's fragile stuff so I'm not entirely sold on its place in RC tanks. There are some neat pieces, but I don't expect to use all the parts.
Preliminary Research: I spent some time looking for info and pictures of the Panther Ausf. G (late version) to help me determine what my finishing options were if I wanted to respect history. I was surprised that there appeared to be so few options; it seems that the safest pattern would be the green, brown & yellow "Ambush" pattern (without the dots) that I wanted to avoid when I made my King Tiger. Actually, the Ambush pattern has grown on me (probably from having seen so much of it) and I think that a tank with a lot of green would be different enough from my KT's yellow-based Ambush-like paint scheme. Also, now I'm not as concerned about paint scraping down to the plastic's molded color since the finishes I've been doing have been so dirty. It's not hard to disguise a real scrape as a fake one. Anyway, I found pictures of someone's rendition that I really liked (but unfortunately don't know where I found them).
The Build Starts: As usual, the stuff from ETO Armor arrived quickly, so I had the important stuff to begin work with: The wheel bearings, the turret rollers and the mantlet. The photo-etch set would satisfy my curiosity, and the antenna and elevation arm would be available later on when I needed them.
The Impact muzzle brake wasn't quite what I expected: It was a single piece metal casting that had been welded/cast from parts, with an deep seam between the what were originally halves; the two halves weren't very well aligned where it fit on the barrel, so it wouldn't fit without some work. I did make an attempt to fix the seam by grinding, but the seam was too deep and the shape would have been ruined. Fortunately, Impact had sent me another as an unexpected freebie for an unrelated shipping glitch, and the alignment on that one was much, much better. This time, I used putty on the seam, painted it, and all was well. Although I'd ordered an aluminum one from Stellamodels, I chose to use the Impact muzzle brake because it was more accurate.
The Wheels: The wheels are the most repetitious part of the build, but it's not too bad and goes fairly quickly. At first, cutting rubber tires from the sprues was a little stressful: I wanted to do a good job, so I went slowly and carefully, which isn't the best approach to take. As I got tired of doing it this way, my cutting method evolved into keeping the blade indexed to my fingers as I rotated the tires against my fingers. This produced a more uniform cut angle and was very fast.
I was forced to commit to the yellow/brown/green paint scheme before building and installing the wheels, since it's hard to paint just the wheels with the tires installed unless you mask them (which is more work). That's something to think about if you want the fresh-off-the-assembly-line look, or use that as a starting point for weathering. On the other hand, if you're going to do heavy weathering, it's probably not such a big deal. Most of the better-looking models I saw had heavy weathering; the wheels & tires were a dusty brown color. In either case, you should paint the wheels, the arms and the hull some color before assembly. It's also a timesaver to temporarily fit mounting screws in the hull so that you won't have to spot paint them later, when you get to those steps.
The Mantlet: Impact's mantlet is a "required" upgrade, since the Tamiya mantlet's bore is too big and the barrel wobbles around in it. Because the Impact mantlet's bore is smaller, it also allows a wider range of elevation. There are other fixes available (Daryl Turner makes a insert sleeve for the Tamiya mantlet), but the Impact mantlet is a bargain, well-made... and one heavy mutha! It's made of metal, and some inner surfaces aren't entirely burr-free, so de-burring and polishing is a good idea before test fitting parts so they don't get scratched. The barrel fit was a bit too snug at first; polishing and greasing the bore of the mantlet made the barrel fit like a pneumatic piston, with no scraping of paint (besides the initial dry-fit scrapes).
Another concern was the weight: Between the barrel and the mantlet, there's a lot of metal up front, and I was afraid that this would stress the elevation motor. However, due to where the pivot pins are located in the mantlet assembly, the mantlet's weight isn't much of a factor. The recoil mechanism counterbalances most of the barrel weight-- the kit's spring gizmo isn't needed and wasn't installed.
There's another weight/balance problem though: With all the weight up front,the front end of the turret noticibly dips since there's play in the turret-hull interlock. This affects its operation and may cause scraping, despite the replacement turret rollers (see below). The solution is to add weight to the rear of the turret, to balance it out. It takes quite a bit of lead to help offset the weight of the barrel and mantlet.
Naturally, adding all this weight to the turret introduces yet another problem: The turret base is made of plastic, supported near the center by the 3 rollers, with a lot of weight around the periphery. This tends to distort the base and hull, and causes dragging against the hull. The solution is to affix brass tubing supports to both the turret base and the hull near the turret opening. When the two are rigid, the turret spins like a Lazy Susan with momentum (from all the weight).
The Turret Rollers: These are a highly recommended replacement for the ones in the kit, since they raise the turret just enough to avoid scraping the hull as the turret rotates. In my King Tiger they installed easiliy and worked perfectly without any modifications to the turret ring; with the Panther, I had to thin the retaining flanges significantly to ensure that the turret would spin freely on the rollers.
Photo Etched Parts: I'd only used photo-etched parts once before (not counting grills), for my King Tiger's star antenna. I bought it to replace my home-made version, which didn't look so good with an asymmetrical blob of solder at the base of the 6 radial antennae. The Wecohe kit looked much, much better-- but was also much, much more fragile than the one I'd made with piano wire. Therefore, I was skeptical about using the 6-sheet Impact set for my RC tank. I bought it mainly to satisfy my curiosity about the stuff, since I've seen so many nicely detailed models that used it. (Besides, Impact's set included grills which I consider a required addition.)
Indeed, I encountered the issue of fragility first up on the instruction sheet: The pioneer tools' clamps. They're made of three pieces: The latch with 2 pairs of hinge holes for the base and the strap. The parts are etched so that they fold easily with finger pressure (or you can use tweezers; score marks are on the inside of the fold). After folding the pieces, you insert the base and strap pins into the latch and you have a working clamp! Well, almost. If you had 1:16 scale personnel operating the hardware, they might find it usable, but for 1:1 folks like me, the thin brass is likely to bend and open the hinge to release the tiny and easy-to-lose parts.
That pretty much sums it up-- perfect for a static model, but not so good for an RC tank that you're going to be handling. (The notable exception to this is the miniature bike chain that secures the barrel-- after construction, the parts are packed so densely that the chain is sturdier than the molded plastic part, and it works like a chain-- you can wrap it over the barrel, or dangle it off the side! In my opinion, it's the star of the entire 6 sheets of photo-etch.) However, photo-etch doesn't necessarily have to be exclusively for static models and shelf queens. You can use superglue to make sure parts don't move, and to add some rigidity. In other words, you glue the clamps to the tools and squirt superglue into the mechanism so that it doesn't fall apart. This doesn't stop the parts from being crushed and deformed or inadvertently sheared off, but at least it keeps the assemblies from falling apart and helps make the assembly more rigid. Why bother? Because it looks great up close. It's the same reason that folks grind off molded-on tools and replace them with discrete tools.
Photo-etch is ideal for intricately-shaped pieces with a thin, flat profile, but it's not always the best choice. It's practically 2-dimensional, and looks just fine for straps and the 4 sheets of armored skirt, but funky for things like wingnuts, pins, and chains-- cast versions are much better looking and more durable.
Another point: Many of the actual tank parts that are being modeled are different thickesses, but the photo-etch is supplied on sheets with equal thickness (actually, thinness). That's evident from looking at photos of the 1:1 version-- the photo-etch versions of the track hangers and exhaust supports look scrawny, but the equipment clamps look just right. Fortunately, it's easy to construct replacements of simple parts with thicker copper, and the photo-etched versions are useful as fabrication templates.
I did this for the track holders, which presented a different kind of challenge: How do you get this stuff to stay put? In many cases, superglue or contact cement works fine for gluing metal to plastic. However, I planned to use metal tracks as the spares, so the track holders needed to be strong. The glued-on copper holders I'd made could be sheared off the plastic far too easily. I then made copper mounting strips to replace the plastic ones and tried to solder the holders onto them... This was really difficult since the holders didn't end up exactly where they needed to go, which is very important if you want the tracks to fit! My final solution was to drill holes through the center of the holders and insert a small Walthers screw through (with a ground-down head), securing the holder and mounting strip to the hull. This solution also makes the tracks removeable (I'd considered gluing them in place) so that the parts can be painted separately.
My lesson from dealing with photo-etch is that you have to use your own judgement: Just because a part's on the sprue (or "fret") doesn't mean that it has to be used. You have to consider whether the part improves the detail without being too fragile. Consider fabricating your own metal parts, particularly if the metal strengthens the structure. Photo-etch looks jazzy when it's shiny metal, but will look just like all the other plastic parts after it's painted.
The Drivetrain: I'd read that there have been problems with the fit of Tamiya's plastic tracks & sprocket, but I'd planned to replace the drivetrain with Impact's stuff, so there wasn't much point in testing that. If your Panther has this problem, buy some Impact tracks and sprockets. Impact makes top-of-the-line closed-pin tracks, and they hang very nicely between the sprockets & idlers. Impact tracks also take chemical blackeners very uniformly, which isn't true for all metal tracks.
I was happy with the Impact gearboxes in my King Tiger, so I got some for the Panther too. The Tamiya gearboxes are silky-smooth and quiet but the gears are a mix of brass and plastic, which isn't as long-wearing as the steel gears used in the Impact gearbox-- not that that would be a likely issue for most folks (myself included). Replacing them just gave me more options since Impact makes optional "hop up" gears for fine-tuning the gearbox speed.
Impact suggested that I probably didn't need to use the 3:1 Drop Down Gear since the Panther was a speedy medium-sized tank. I tried that, but ended up using the DDG because slower makes the tank a lot easier to drive. (Tamiyas have a tendency to turn abruptly when the joystick passes a certain point-- It's heresy, but I actually prefer the way Heng Long tanks drive.) I replaced the motors with the Graupner Speed 400s, fitted with Impact's 12-tooth steel pinions.
Since Impact's gears are made of steel, the gearbox is quite noisy at first. In my opinion, they should be modified and broken in before use. The first modification is to elongate the motor mounting holes so that the motor position can be adjusted for a good mesh between the pinion and the gear. This is easy to do with a Dremel using a steel cutting burr. This is very important since a poor mesh will cause the pinion gear to be eaten up by the steel gear, especially if you're using the soft brass pinion included with Tamiya motors. The mesh can be especially bad if you're using the stock motor mount holes and the Drop Down Gear. The mesh should be not too tight and not too loose-- you don't want play between the gears, but you also don't want to make the mesh so tight that the motor has to strain. Always check before running the motor.
The second modification is more of a "fix" and involves grinding down one of the spacers for a gear located mid-way in the gearbox. You can easily spot it because it tends to spin, and if you press against it, you'll hear and feel it grinding against an adjacent gear. To fix it, I use a Dremel with a sanding drum: Remove the spacer and place it on a loose-fitting axle (like a small screwdriver) so that at rotates freely. Run the Dremel at a slight angle, perpendicular to the screwdriver. This should make the spacer spin, and will grind the spacer with a concave profile. Varying the angle will change the rotation speed and degree of grinding. You should grind a generous amount along the length since the adjacent gear may drift side to side under load.
These mods should quiet the gearbox considerably, and to be honest, the consumer really shouldn't have to do this-- but it's easy to do. Once done, lubricate and run the gearboxes in either direction until you're satisfied that they're as broken-in as they need to be.
The Hatches: These were a late addition to the shopping list, and I eagerly awaited their arrival: I didn't want to add detail to the hull until I'd installed the hatches since cutting hatches can be quite brutal.
Hatches are optional upgrades that may or may not serve a practical purpose, but are cool nevertheless. On static kits, working hatches can show interior detail and you can pose crew members in them. In RC tanks, they can allow access to concealed functionality like switches, charging ports, access for gear greasing, etc. All these points are balanced against their liabilities-- they're a pain in the ass to add, reduce structural integrity, may rattle, and give dust and dirt another point of entry. I think those arguments are outweighed by the fact that working hatches provide a sense of realism like separate, non-molded on tools-- on the bare naked kit, you can plainly see that the hatches on the Panther are sculpted into the hull.
Because of the design of the Panther Ausf G's front hatches-- they're flush against the surface with a large hinge on the outside-- they're not easy to cut off intact and reconstruct as working detail. Therefore, buying aftermarket hatches seems to be a much more sensible solution: You just cut through the hatches, grind off the hinges, and replace them with the aftermarket parts. The rear turret hatch would be much simpler to cut out, but the articulation hardware would need to be fabricated: Much easier to buy a kit that's got all that stuff already figured out.
Actually, it's not quite that easy. For one thing, my hatches arrived as a bunch of parts in small ziplock bags, with no instructions. I was fortunate to have a few reference pictures of the inside face of the front hatches, which was indispensible for figuring out where all the parts went (except for two of the smallest screws that I've ever seen!). I didn't have photos for the rear hatch though. Through lucky guesses and trial and error, I figured out the how to construct the working latch mechanism (very cool!) and hinges, but there were a few parts left over that I had no clue about (like a small sheet of photo-etch). While I like the stuff that WeCoHe makes, they seem to like making you wait before you can buy or get info about their stuff.
The front hatches require much more precision cutting of the hull than the rear hatch because the hatches should fit the cutouts exactly. They don't cover the cut marks and if you're sloppy, they'll look funky and may bind. That means a lot of test-fitting and sanding, guestimating where to drill for the hinge posts, and finally adding the retaining lip on the inside (so they don't fall through). I didn't get a perfectly flush fit, but close enough for me.
The hatches are made of metal, but I'd have preferred plastic because it weighs less and puts less strain on the hinges. Metal hinges aren't likely to break, but they are more likely to separate from the plastic hull. In practical terms, it's irritating: Everytime you turn the hull over to work on the tank's innards, the front hatches fall open. The rear hatch tends to open slightly when the tank runs on rougher terrain. Fortunately, it has a locking mechanism (so it can run just like a Panther without a working rear hatch). Unfortunately, you have to remove the turret to access the latch!
The Machine Guns: At one of the forums, "grim_marmazet" came up with a great idea about using a servo and DPDT switch to remotely toggle between the hull and coaxial machinegun-- brilliant! I couldn't use it for either my King Tiger or Tiger because I couldn't fit a working coaxial machinegun in the turret of either without sacrificing installation of the IR emitter. In my Tiger, the IR emitter was fitted in the coax spot, and in my King Tiger, the mechanics of articulating the machinegun through the mantlet and gun base seemed daunting [10/14/09- Actually, I eventually got over it and installed the laser in the mantlet of the King Tiger. FWIW, it wasn't very difficult.]. On the other hand, the Panther has a large full-coverage mantlet, so it's easy to mount a machinegun and an IR emitter.
Fortunately for me, "tailend charlie" at RC Universe refined the machinegun switching design by using a momentary contact switch (available at Radio Shack) with the servo-- this makes the servo's work easier, and it's a breeze to mount the switch to the servo with servo tape. I converted my lighting circuit to a manual switch so that I could use the transmitter channel to operate the servo.
When building my King Tiger, I discovered that the Tamiya machinegun circuit (CN3) didn't have enough "juice" to operate a laser. I finally got around to inspecting the circuit and discovered that CN3's voltage was limited by a surface-mount resistor, R18 (approximately 150 ohms). By adding a jumper around that resistor, a higher voltage was available at CN3, enough to drive a 3-5 volt laser. This worked perfectly with my plan to mount a coax laser to the turret and keep the LED in the hull-- I just needed to add a 150 ohm resistor in the LED's path and remember to never plug an LED directly into the DMD/MF unit.
The mod works perfectly. The mantlet's motion-- rotation and elevation --is well suited for playing with the laser indoors. (I don't think that lasers are useful for outdoors IR/airsoft battling because it's very hard to see a 5mW laser in sunlight.) The LED is much better for simulating the machinegun fire at the tank because the fiber optic insert makes the simulated gunfire visible at the barrel from front and side angles. You really can't see the laser fire except for where it's projected, or if you're standing in front of it.
The Recoil Mechanism Upgrade: This was another late addition to the shopping list; basically, a discount offer fell in my lap. I've been very pleased with the Impact kit I installed in the King Tiger, so I figured, with the bucks that I've already sunk into this, why not? To save money you can DIY by modifying the stock recoil unit: Grind some teeth off the main gear and add a spring... but if you botch the job, then you need a new recoil unit. You also don't get Impact's metal replacement gears (a good idea since the spring slams the toothed section of the main gear into the spinning drive gear) and a voltage regulator to change the return speed (Not essential, and if you don't use it for that, it's a convenient gizmo to have for tapping CN5 and dialing in/regulating the voltage to the LEDs).
Unfortunately, the upgrade didn't come with instructions and I didn't find any online. The Panther's recoil unit is similar to, but different than the King Tiger's, so the shaving of the main gear couldn't be directly copied from the King Tiger's. Not having instructions forced me to follow my instincts. In some ways, the installation is easier than the KT's since you don't have to cut away any of the plastic housing for clearance. I omitted the included spring mounting screw and just drilled a hole for the spring in the metal barrel retainer, in line with the spring.
The barrel-mantlet fitting and spring's setup are the most critical determinants of whether the thing will work; that's because the barrel/mantlet fit is so close, like a piston. If it's pulled off axis, it will tend to bind. With the upgrade, the retract motion isn't driven by the teeth of a gear, but pulled by the un-torquey tension of the spring. If everything is perfectly aligned and working smoothly, the spring snaps the barrel assembly back. If that's not the case, the assembly will hang up and the cycle won't complete. Given that perfection is elusive, you can help force the issue by increasing the spring tension. However, the spring can't be so strong that it strains the motor and gears when the mechanism returns to battery. As you might guess from my excessive rambling, I had this problem... my solution was to bend the upgrade's spring retainer mounting backwards, folding it down. This effectively increased the spring tension and aligned the spring closer to the axis of the barrel travel (which means less upwards pull, i.e. friction). Works as designed, with no further problems. The Panther's recoil unit is smaller than the King Tiger's, so it has less barrel travel; therefore, the quick recoil is less dramatic and impressive than the King Tiger's.
My one caveat about these "realistic" recoil modifications is that they all rely on using a spring to pull the barrel back quickly. This means that for 99% of the spring's life, it's in its fully stretched-out state-- which isn't great for the spring. I suspect that over time, these modification will require replacement springs. If one determines that it's too much of a hassle to replace springs, having used an upgrade kit will seem like a smart move, since you'll have all the parts to revert the mechanism back to its stock configuration.
The Turnigy Speed Control: This gizmo installs between the receiver and the throttle channel of the DMD unit to slow the rate of change in the throttle, simulating the feel of momentum (It's actually designed for RC planes, to slow the rate of the landing gear retraction). I found out about these from the forums, and installed one in my King Tiger. It's not as full-featured as the momentum & braking that's programmed into the ElMod and DBC boards, but it's a nice feature to add to a Tamiya (as long as you don't go overboard, or you will probably run into things). I think the main benefit is that it keeps the tank from immediately launching when you move the joystick, especially if the tank is sitting on your workbench!
I was surprised that I had such a hard time dialing in my Panther's Turnigy unit. There are 3 trimmers to adjust and I thought that I had them figured out for the King Tiger. My Panther has a peculiar quirk (I think it's related to my DMD) where the stops in reverse are occasionally very abrupt-- not good for the gearbox! I've used the Turnigy unit to dial this out, but it took a lot of trial and error tweaking. At any rate, I wanted to have the trimmers accessible without digging into the tank, so I mounted the unit on top of the speaker box, beneath the left air intake. The air intake cover is secured with a magnet.
The DMD-Multifunction Unit: This falls in the category of "wretched excess", but it bothered me that my Panther sounded exactly like my King Tiger. That's because they both come with an MF-01 unit. Although both real-life tanks had the same engine, I'm sure that they didn't all sound exactly alike, with the same start-up sounds and running sounds. It bothered me enough so that I bought Tamiya's Panzerkampfwagen IV MF-05 unit to replace the MF-01. It's a direct replacement, and I think the only difference is in the sound chip. As for it being a recording of a Pzkpfw IV and not a Panther, hey, it sounds like a tank to me.
I'm happy with it, even though the MF-05 doesn't have turret turn and gun elevation sounds and the machinegun and cannon sounds appear to be the same as those in the MF-01 unit. The start-up sequence is noticeably shorter and the running/idling sounds are very business-like. It's an expensive indulgence, but adds some variety.
Things to Do While You're Waiting For Parts to Arrive: It can be aggravating waiting for parts to arrive since it could be stuff that you want to work on, or stuff that you can't work on until after you've finished working on the stuff that you're waiting for. Although the instructions provide a linear path to follow for construction, you don't have to follow them, and sometimes you shouldn't, especially if you're using photo-etched parts that require deviations from the normal order of assembly. It's a good idea to study all the instructions and figure out what's okay to do out of sequence, and what should wait. Parts that will be inaccessible after assembly should be painted or primered before assembly. Some detail parts can be glued on at any time, and should be attached before painting. Some should wait until after the basecoat is painted. While it's fun to test the electronics stuff early, the wiring can dangle and snag, making it more frustrating to work on other stuff. If you've got grinding and cutting to do, it's easier and safer to do it before you attach delicate parts.
The waiting-for-parts-to-arrive time can be a valuable and productive time to come up with and test ideas, and go beyond the usual level of detailing. After I'd glued on as many "safe" parts as I could, I worked on the extras while waiting for the last part to arrive (the DMD/MF-05): Exploring the photo-etch parts, mounting the IR emitter housing in the mantlet, mounting the volume control, making a working headlight and convoy light, putting screws through the towing shackles, adding weights to the turret, adding brass supports to rigidize the hull & turret, figuring out how to make the laser work, making the selectable machine gun system, devising a sturdy spare track mount, etc. If I'd had everything I'd ordered at the start of the project, I probably would have breezed through it, without taking the time to think about additional features and refinements. In fact, once my last order arrived, I almost regretted not having any more excuses for not moving on towards the finish line!
THE FINISH LINE
One of the things that bothered me about this kit was that the texture on the turret sides was too perfect-- unlike the King Tiger's turret which had tiny pits and gouges, the Panther's turret walls were perfectly smooth, like a sheet of virgin styrene. In addition to that, the turret is cast with a faint indented trough all along the bottom edge of the turret (including the back piece). Once you notice it, you can't un-notice it! I wondered whether this was an accurate feature of the Panther's construction, or just a consequence of the plastic casting process. I also wondered whether the turret's surface texture was really supposed to be that smooth. Unfortunately, photos didn't help much. It looks as though the texture actually was that smooth, and that the indentation isn't supposed to be there. Nevertheless, I decided to give the flat surfaces a subtle texture-- less than the simulated cast texture, but enough to make them look less perfect.
Miscellaneous Detail Doodads- Glues & Screws: In the course of the build, there are some detail parts and subassemblies with photo-etch that really shouldn't be added until the very end. Before the first airbrushing session, you have to decide what gets attached and airbrushed with the rest of the tank, and what gets brush painted later and attached to the tank. Although you could mount everything and paint them in the camouflage colors, I prefer the look of separately painted tools.
I classify some parts for permanent mounting and others for a less permanent mounting, then try to figure out what kind of attachment to use. Generally, I try to use the least aggressive glue I can, depending on the piece, where it's mounted and its likelihood of it coming off. I prefer to attach light parts like tools with contact cement so that I can easily remove them without damage if I want to repaint them, or add wooden handles. Parts like that don't need a strong glue. If I'm sure the part will never need to come off, I'll use a solvent glue or superglue.
Superglue works great in many situations, and a metal-to-plastic join may seem strong enough, but can break suddenly with only a moderate shear force. If it's a small part and this happens outdoors in grass or leaves, you can probably write off the lost part. Contact cement doesn't form as strong a bond, but since it's pliable and sticks to metal like tape adhesive, there's a chance that the part will remain with the tank, even if it's loose or dangling by a few strands.
When a larger part needs to stay put and there's not much glueing surface, I don't trust the bond to glue-- I use screws. The antenna storage cylinder is a long piece, but it's attached to the hull by only two relatively small attachment points, and projects out from the hull-- it's a prime candidate for being snapped off, or having the bond broken by the hull flexing or twisting. Although cements like Tenax and Ambroid fuse/melt styrene, I've seen those bonds break with moderate shear force. Screws are a better solution when you want to be sure the part stays on.
The fire extinguisher is a similar shape and projects out from the hull, but it's much shorter and has more surface area contacting its mount. It's also somewhat sheltered by the surrounding tools. Therefore, (and because I used the metal photo-etch kit), I used contact cement to attach it, although a screw would have been a more secure attachment. Screws may be impractical and overkill in some situations, particularly if the parts are thin and fragile.
Painting: I started by trying to use spray paints, but quickly discovered that it's hard to do a multi-color job unless you use masking tape and want hard-edged lines. For a large object like this (unlike the wheels), the spray can nozzle doesn't give enough control to hand hold masks for a feathered effect, so you get a lot of undesireable overspray. Forget trying to do multiple colors. Although airbrush paints aren't as durable as the spray paints, it's much easier to control where the paint goes when you're doing it freehand.
The airbrushing session was a little more aggravating than usual. Of course, there was the usual stuff-- paint too thin, paint too thick, sudden blasts from the color cup with the resultant spidering, color cup falling off, spinning and spattering everything on the way down, constant cleaning of the nozzle, etc. The compressor failure was the special aggravation this time: The auto shut-off sensor stuck at 100 psi, so although pressure had dropped to zero, the compressor refused to fill the air tank. I jury-rigged a fix, and managed to finish the basic camouflage coat. After adding decals, I went back to spray a coat of dust, but the a couple wall outlets stopped working... It wasn't a tripped circuit breaker, and mysteriously the power returned a few hours later. I hate letting mysteries like that go unexplained, but really didn't want to get involved climbing in the attic, tracing house wiring. After running the tank outdoors with its extremely fresh paint job, I had a second go at the dust coat-- This time it went a little better. However, a final coating of Dullcote seemed to knock the dust coat back a bit.
It's "finished" until the next time I work on it... and I still don't have any regrets (except, "where am I going to put it?"). Having acquired & built this right after modding my HL Tiger with ElMod electronics, I'm inclined to compare the two. While I was finishing up the Tiger, I was thinking about putting ElMod electronics in whatever tank I happened to acquire next-- even if it were a Tamiya. During the course of this build, I played with both and decided to keep the Tamiya electronics. It's a close match-up, and the pros & cons weigh equally on both sides, so it was just the path of least resistance. The main reason was that running the tank with Tamiya electronics felt good... everything worked as expected, it ran reliably, and I didn't feel that it was lacking anything that I couldn't live without, especially at the expense of its positives. The ElMod's built-in momentum is more realistic than Tamiya's with a Turnigy circuit, and it allows braking-- a very cool feature that's not available in the Tamiya. The ability to operate the turret and guns while the tank is asleep is also a cool feature. However, the ElMod Tiger doesn't have as much "get up and go", which I feel detracts from the basic quality of "fun". Controlling it to lumber around slowly, though realistic, can get boring. There are a few other things that I don't like about my Tiger: The gun elevation servo moves sooooooo sloooooowly, and its mushroom accepts hits at 45 degrees. I'd read that ElMod (the company) would soon release a revised software chip to address some of these problems-- but it's not available yet, and I believe in the here & now (Heng Long's new Panther isn't out yet either).
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