Introduction: Build a Model Tank: Tristar Marder III
John Prigent takes us through the first part of his 'Out Of The Box' build of the Tristar Marder III H. Originally published at hobby magazine http://www.militarymodelling.com/ give it a try and let us know what you think.
I decided the other day to haul a Tristar Marder III Ausf H out of my stash as an out-of-the-box build, having spent rather a lot of time on upgrading models this year. First impressions are of quite acceptable mouldings, a lot of photoetch parts, and reasonable instructions. Then I noticed that Tristar has left out any painting instructions for the interior, which strikes me as downright stupid when this is not a beginners' kit but one for fairly experienced modellers who can be expected to want to get the detail colours right. Beginners will never know what to do with all those tiny etched parts (or how to stick them on) so will probably just leave them out and paint everything the exterior colour!
Anyway, I began at the beginning with the gearbox. The basic box is well done, with the ribs all present and correct as far as I can tell, and the plastic parts fit well. Adding the etched brake bands is straightforward, though it is essential to anneal them first so they'll take the curve. Annealing is easy, I just hold the part with tweezers at one end and use a throwaway lighter to heat the other end red hot. I wait for the colour to nearly reach the tweezers, then turn the part round and repeat the heating so it's been red hot all through. Let it cool naturally, wipe off any soot from the flame, and it's now soft and easy to form into a curve. The reason for doing the heating in two stages is simply that you don't want to anneal your tweezers as well if you soften their metal their points will bend in use and youll have to keep straightening them believe me, this is the voice of experience! You can use a candle or one of those plate-warming stubby candles for the job, but a throwaway lighter has the great advantage of going out when you drop it. That means it simply cannot set light to anything else! I only anneal things that need curves. There's no need to do it with straightforward bends along the etched lines provided, unless perhaps if they're very complex and close together, though I've not found any that needed it myself.
Then the etched "fun" starts, with no fewer than 6 levers, 5 washers between them, 2 arms to attach to the levers and 2 tiny folded pivots to attach to the equally tiny ends of two plastic rods which then get trapped on two of the other levers. I have to say that this is a rat's nest. In the first place, Tristar has you add all these levers and washers onto one thin spike as their pivot - which sounds easy but isn't when you realise that they take its whole length with no margin of safety. In the second place, the spike has been moulded onto the _top_ section of the housing but the drawing is seen from above, so you have to try to think upside-down to get them onto their spike in the right order. When I build another Tristar Pz 38-based model I'll try drilling the base section to take a brass rod spigot instead, so I can fit the bits more easily. Oh, I nearly didn't mention the fun when you try to turn the whole lot the other way up to fit it to the bottom section - it took me ten goes before I got them all there with nothing fallen off. A further etched part goes on the end of the housing, and will of course mean that all the levers are stuck solidly so it's vital to get them lined up correctly before adding it. I cheated, and left the ones that need to connect to the brake drums and final drives (PE18/H21, PE18/H22, PE 16 & PE17) until everything else was straight. With that done I added drive shaft and its PE cover, a nice simple job but again needing the cover to be annealed so it would take the curves over the shaft.
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Step 1: Gearbox
Here you can see the problem of getting those two long front arms at the right angles. If they're fixed solid at the wrong angles they won't end where they should at a later stage. Mine are still loose here, and will stay loose until I fit them between the gearbox and the tops of the final drive units.
When it comes to interiors I prefer to work in sub-assemblies as much as possible and paint them before sticking anything I'll find it difficult to paint later. It's pretty obvious that painting the seats will be tricky later if they're in place, so for stage 2 of the instructions I just added their bases and the various other bits that go on the hull floor. Then I dry-fitted the gearbox assembly to line up the firewall, and fixed that in place. More etched parts go on the firewall itself, but they're straightforward once you realise that the diagram in stage 1 shows the back of it. Watch out for the tiny plastic handle H41, though, it is small enough to be a right so-and-so to grip without tweezer launch sending it to the carpet monster. There are some ejector pin marks on the floor that need to be filled, as you can see here; don't overlook them as "invisible after completion" because they will be visible. There should be some wires from those "boxes" on the floor, connecting to the radios and also back to the battery behind the firewall (the boxes are transformers for the radios) but I'm doing this model out-of-the-box so I haven't tried to work out whether they can be seen in order to add them.
Step 2: Hull Floor
The fit of the gearbox assembly to the hull floor is absolutely critical. I had to remove that top assembly with all the levers and refit it with a bit chopped off the bottom so it didnt foul the glacis plate and force it up into a curve. I think the problem is caused by moulding constraints - the glacis is thicker than scale so there's very little margin for error in assembly. Maybe I used too much cement in putting the gearbox and lever assembly together so it's higher than Tristar intended. Fortunately I managed to chisel under the top section and bend it down a little, and chiselled more away from its top under the glacis plate so everything fitted. I was able to leave intact the parts that show through the transmission hatch so even if that is left open it will still look OK.
A further note for anyone building this model - it will not be possible to fit the accelerator pedal and its linkage with the starboard hull side in place, you simply cannot manoeuvre the linkage round the final drive shaft. The answer I adopted was to fit the shafts to each hull side, then the linkage and pedal to the glacis, then fix the port side and glacis and finally fix the starboard side. The drawback is that I had to put the rods mentioned before in place between the levers and the drive housings on the hull; the port one can be done before the glacis is in place, but the starboard one is an interesting exercise in tweezer manipulation.
Meanwhile, here are the two assembled seat frames. Note how the straps on the backs fit over the top of the backplate - they go under it to the bottom of the back-cushion when that and the seat-cushion, left off at the moment to await painting, are added.
Step 3: Seats
A shell rack fits in the port bow. It comes as a mounting frame, two rows of empty tubes, two end pieces to connect the rows of tubes, and a bunch of tapered shells to put in them. Plus an etched strap to go round the lot when they're together. Here I've assembled the back row to the frame and added the end pieces and the shells. There's no way I was going to try painting the shells with the whole lot together, so I kept the two rows separate and did the same with the other shell racks that go in the main gun area.
Step 4: Bow Shell Rack Subassemblies
I put the radio rack together next. A nice easy job at first glance, with bending lines provided. But.......
As you can see, even with my bending tool it was almost impossible to keep the bottom truly flat while I bent the frame to shape. Fortunately it is invisible under the radios! The centre part has locating points etched inside the frame so all that's needed is a dab of gel superglue on the part and care in slipping it into place so it doesn't get stuck out of line. The rubber shock-absorbing mounts fit well between the frame and the actual metal mounts, but be careful cutting them from the sprue - three of mine broke and had to be stuck back together.
Step 5: Radio Rack
Here are the two hull sides with their internal parts added. Two things need a bit of care - first, the small box on the starboard side has a channel on its back to let you fit it correctly over the bend of the cable. In this photo I have it in the wrong place, the lower part of the cable needs to emerge from the centre of the box's bottom not as I have it. Yes, I did take it off when I realised what was wrong, as you'll see in a later photo. Second, be careful with the two H-13s that go on the final drive parts H12. There seem to be location points for them, but in my kit they weren't very positive and I couldn't know if they were right till I fitted the rods that join them to the gearbox lever assembly.
Step 6: Inside Hull Sides
Tristar seems to me to be using PE in some places where plastic would do just as well. The driver's levers of the 38(t) series for instance are rather thin in PE and plastic would have been closer to scale size. And instructions are sometimes impossible to comply with. For example, they have you add the glacis and the shaped PE pedal lever for the 38 (t)s at the same stage, after fixing both hull sides. But it's impossible to get that shape of PE round the final drive shaft once the PE part is fixed to the glacis, and equally impossible to fix it to the glacis after that is in place. Another example: if you add the radio operator's seat in what looks like a logical place you can't get the port-side ammo rack between it and the firewall. So I painted the ammo racks and rounds and fitted the port one before that seat. The effect when finished is great, it's just that you have to wonder whether anyone at Tristar actually built the model following the instructions or if the instructions were written and the diagrams drawn entirely separately from the actual assembly of a test shot.
Now here's a view of the painted starboard hull side interior. I moved that box to the correct position but the main point here is to say that the leather padding, according to my sources, is not the usual German black but red-brown leather instead. There is some doubt about the fire extinguisher colour, with green rather than red appearing to be the usual colour before the 1950s so I've painted mine green - note the clips that held it, they're not a strap. Michael McLaughlin's information from a Pz 38(t) owner is that the interior was off-white, and mine from a Czech source who's inspected a number of tanks is that it was ivory. Hmm. I opted to go with off-white, as seen here. Note that the German Pz 38(t) manual shows this extending all the way along the side, not ending at the slanted hull joint in front of the driver as seen in the MBI book "Praga" on the Pz 38(t) - the preserved tank photographed for that book is painted in the 1950 interior standard method, not as it was in wartime.
Step 7: Painted Starboard Hull Interior
At this stage I've added the two portside shell racks and radio operator's seat. That seat is a very tight fit between the two shell racks, which is why I added them first. I've studied the manual photos again and concluded that the floor was a dark colour, probably Czechoslovak "khaki" which my friend who's examined tanks tells me is a greenish colour ,not what we usually think of as khaki. After looking at all my paint collection I used Lifecolor UA221, khaki olive drab. I used the same for the hull shell racks and the V-shaped rear support for the gun base, on the basis that they were likely to be supplied by contractors and that seems a feasible colour. The manual photos show what seems to be bare metal on the gearbox and drive unit, and the drive shaft cover that isn't fitted here, so I've used Humbrol polished steel. There's enough flex in the firewall (it's only stuck at the bottom) to let me slip the driveshaft into place later, and getting the seat into place with it in the way would have been tricky to say the least. It isn't clear at this angle, but I painted the steering levers grey with wood handles on the advice of my Czech friend who tells me that's what they were originally. I've also painted the radio transformers grey, but there seems to have been some variation for those. What you certainly can't see at this angle is that the cross-shaped tool on the firewall is black, and so is the small handle on the port side of the firewall. The recessed panel in the firewall is bare metal again, this time aluminium, with control black handles.
Step 8: Tight Fit of Seat and Shell Rack
The shell rack in the front hull needs to be carefully positioned in order not to foul the glacis plate. When you dry-fit the glacis you'll see that there's a cutout on its port side that fits round the rack; the rack needs to be right inside that cutout. In my kit it was not quite wide enough so I had to widen it about 0.5 mm to let the rack go back into it, but I think I may have got my outer tier of shells at a slight angle and so made the rack wider.
Here are the radios in their rack - no need to superdetail them as they're quite hard to see when the superstructure is in place. Radio colours seem to have varied - maybe according to which manufacturer made the case that the works were put into? For this model I used Humbrol 32, a "panzer grey" which looks to me like one of the colours used. Though I'm comparing what's in the tin with my monitor's rendering of the colour in an online photo and the colours seen in books, and we all know how misleading computer colours and printed colours can be.
Step 9: Painted Radio
And here's a view of what the instrument cluster should look like. Don't ask me why there's a cage over one of them, there really was on the real tank and it is a pain to paint. Note the correct position for the handle H-18, it should be under the rear pair of bolt heads at the port side of the glacis but it could be left off as it can't be seen behind the shell rack.
Step 10: Glacis Instruments
On dry-fitting the driver's front plate I found a potential snag to warn other modellers about: The steering rod assembly can force the glacis up into a curve if it's slanted too far up. Luckily mine is only slightly too high so the driver's plate has only a slight curve under it which I could deal with, but this is something to take care over.
As mentioned above, its impossible to add the suspended pedal to the completed hull. Here are photos showing how the control rods and that suspended pedal need to line up under the glacis. There's really no way to do this except with the port side and glacis fixed first but the starboard side left off - trying to manoeuvre that suspended pedal round the final drive axle is a non-starter if you follow Tristar's sequence and fix both hull sides before the glacis.
PE-19 from the gearbox goes on first, then PE-20 which is the suspended pedal, and finally the rod from the steering lever to the final drive. That rod turns out to be rather in the way when you're fixing the two PE parts, so I took mine off and refixed it after dealing with the PE. Note that it goes over PE-20 so it points at the right angle to link to the top of the final drive.
Step 11: Control Pedal Arrangement
A lot of that interior will be effectively out of sight once the upper armour and gun are in place.
Step 12: The Completed Interior
This was of course before I added the driver's front plate. Here's the inside view of that. I used the plain glass for the driver's vision port, for a change because I built the Pz 38(t) a while ago with the armoured glass in place. Don't ask me where the armour-glass block was stored while not in use, or the plain glass one while that wasn't being used - I can't find any trace of stowage arrangements for either. Note the plain wood handles for the MG and the operator's vision port, and the bare steel MG ball - I used Humbrol metalcote for that. The internal ring round the ball is black, and so are the vision port frames which have brown leather pads. I've fixed the operator's port closed, since no-one could easily get near enough to use it. Apparently there were only three crew members for this little beastie: driver, loader, and commander/gunner/radio operator. I can see the point of not having a separate operator underfoot, and the usual headsets were in use for intercom so clearly the poor man was able to hear the radio while frantically multi-tasking though it must have been awkward to reach the radio controls down below the gun - no doubt the reason for a proper seat being down there. I expect you're asking "why the hull MG if it was out of easy reach and there was no spare body to fire it?". The answer is that yes, it was fitted and can be seen in many photos, and it was fired as a fixed gun by the driver using a bowden cable to its trigger. Reloading must have been an "interesting" job, and "spray and pray" rather than actually aiming the method of use. I haven't fixed it yet in this photo but it will be fixed horizontal and pointed straight ahead when I do.
Step 13: Outside the Drivers Front Plate
And here's the outside of the plate. Not a very interesting photo but included so I can say that you shouldn't go desperately searching through the sprues looking for part C19 - "there ain't no such animal". Tristar seems to have goofed here, though I'm not sure how or why. The MG ball is actually held in place by D21.
Step 14: The Neat Etch Inside the Engine Hatch
The next stages need more pre-assembly and pre-painting. Here's a shot of Tristar's neat etched grill under one of the engine hatches. I haven't bothered to fill the ejector pin marks since my hatches will be closed, but of course anyone building the Pz38(t) kit that comes with an interior will need to do that.
Step 15: Starting the Gun
I also started on assembling the gun and its mount. The barrel and breech are straightforward, though the breech block is a very tight fit into the breech thanks to excess plastic on its top surface where the milled section of the real thing is a little over-emphasised. I had to trim this a bit to get it flatter so the block would go into place, but it is now tight enough to stay put as well as loose enough to remove for painting. In this shot you'll also see the underside of the gun slide, which has the usual horrible join down its centre and leaves a tiny but noticeable gap at the breech end. I puttied the join and squeezed it right through that gap. Hence the underside view - close inspection will reveal the green putty in the joint at the breech end.
Step 16: Hull Rear Ready for Silencer
In the next photo I've prepainted the area where the silencer will go so I don't have to try to paint neatly around it. Those who have the Tristar Pz38 (t) kit series will spot that I haven't added the A-26/PE-72 parts at the top of the round access plate. There are two reasons for this: 1 - the carpet monster got one of my A-26s and I can't find it; 2 - these are the upper supports for the tow cable that Tristar didn't bother to include so adding them might be a bit pointless. The cable should wrap round these two parts and the bottom of the tow hook, with the PE bits holding the cable to the A-26s not dangling pointlessly below them as shown in the instructions. Side thought - why do so many kit makers leave out the tow cables? Tamiya manages to provide thin twine and plastic loops, so why can't DML and Tristar?
Step 17: Silencer With Joint Filled
This photo shows the assembled silencer, mostly prepainted ready for "rust" but with the exhaust end unpainted so you can see where it needs filling. The tailpipe goes into a keyed location, but the opening around it is too wide and leaves an obvious gap. On the real thing photos show that the tailpipe was welded in quite roughly, so there's no need to make this a refined job of filling. My base coat is red-brown so that any gaps in the rust that I apply will simply look like a different colour of rust. Incidentally, German silencers and exhaust pipes were made from mild steel and did rust quite quickly, just like the exhaust on an older car made before stainless steel was used. They came base-coated in a heat-resistant black, the same stuff that used to be sold as "stove enamel", but it did burn off. A newish one would have rust patches starting to show over the camouflage colour and possibly greyish areas where the paint had started to burn but rust hadn't yet set in, an older one would be very rusty if t hadn't been repainted.
You can catch part two on http://www.militarymodelling.com/ be sure to check it out.