Sd.Kfz.7/2. 3.7cm Flak 43. Trumpeter 1/35 kit#01527 (Chapter 1: Construction & prep for paint)

 

3.7cm Flak 43 auf Selbstfahrlafette (Sd. Kfz.7/2) and Sd.Ah.56/57 ammo trailer

 

Kit                       Trumpeter (Sd.Kfz.7/2) #01527
Trailer:                WM resin & 3D printed 

Tracks:                Kit tracks
Barrel:                 ABER
Photo Etch:         Kit supplied etch
Wheels:               QuickWheel QWX-027
Start date            March 2015

 

This Sd.Kfz.7 SP flak kit was purchased many moons ago and within a few weeks 99% of the construction work had been completed. It then remained unfinished until only recently when I found a suitable ammo trailer. The images below are the only ones I have from the build stage. However, many of the main chassis and engine compartment parts are shared across all of Trumpeter's Sd.Kfz.7 kits. Contruction steps from my wooden bodied cargo variant build can be found here. 

 

Like all Trumpeter's 8ton series vehicles these kits can be somewhat challenging to build. Accuracy issues aside, the main chassis is a multi-part affair, and although well detailed, many of the part location points are not very well defined. Many smaller, delicate parts often require plenty of test fitting and judicious amounts of clean up to avoid missaligning assemblies. There are also a few places where crude moulding hampers construction, making swift progress somewhat frustrating. Another problem is the instruction to fix many fragile parts way too early in the construction steps, making damage all the more likely. Once you realise that a fair amount of pre-planning, clean up, and test fitting is required at almost every stage, you have to be prepared to put the time in to rectify these issues. If you do the final result can be rewarding.

 

This is Perth Military Modelling's review conclusion of this Trumpeter kit when it was released.

 

'While this kit again carries over some accuracy issues from earlier versions such as the drive sprocket roller offset, the chassis length and fender profile it also includes excellent details in the engine/gearbox assemblies as the full compliment of driver’s pedals and decals for the instrument panel. But as with the Flak 37 kit what makes this very attractive is the inclusion of the later style road wheels, front wheel hubs, the later style track links and the ”mid” style instrument to allow you to build a correctly configured late model 8ton. The new 3.7 Flak 43 mounting again has some nice details and is overall better done than the Flak 37 in the previous kit. The only real issue being the missing crew seat but as with any kit there is scope for additional detail enhancement to lift the final appearance. The mix-up of trailer features is unfortunate and detracts a little from the overall appeal but the kit still has many pluses to offset some of the minuses'

 

Regarding the drive sprocket roller offset issue mentioned in the PMM review, I had already made the Trumpeter Sd.Kfz.7 KM M11 version without knowing about the issue and I spent a frustrating amount of time wondering why the tracks would not locate correctly! You can find details of the fix here. This link takes you to the fix for Trumpeter kit #01507 so part numbers may be different, but essentialy the same fix is required for all their 8ton vehicles. 

 

Trumpeter's representation of the Sd.Ah 56/57 trailer is also way off the mark. They have somehow managed to fuse the details of two different trailers, so what the kit offers it not at all accurate. I originally tracked down this far more accurate resin kit from Wiener Modellbau.  https://www.scalemates.com/kits/wiener-modellbau-manufactur-wmm35005-munitions-sonderanhaenger-sdah-57--1168423

Build tips 

 

After building almost all of Trumpeter's 1/35 scale range of 8ton Sd.Kfz.7 vehicles please find some tips, advice, and some alternative construction sequencing that I have discovered and recommend. 

 

• In step 1 to prevent almost inevitable damage, leave off adding the cab control levers onto the gearbox until the cab is added onto the chassis.

• In step 2 the gearbox assembly is only connected to the chassis by rearward attachment points. It will pivot unless held perpendicular to the chassis frame whilst the glue dries. If not fixed perpendicular and the alignment is out, fitment to both the engine shaft and the winch shaft will be difficult to fit. As the chassis side rails are flexible there is also no real rush to add it until step five if you wish.

• In step 4 engine part E19 does not sit flush inside part E36. It will require sanding down. If part 19 protrudes beyond the edge of part E36 it will extend the whole engine assembly lengthwise by a few millimetres, and will make engine fitment onto the chassis mounts problematic. Test fit before commiting the glue!

• In step 5 ensure forward engine mount parts B48 are added well before the engine is added so the bond is strong to prevent distortion. Leave shackle parts B37 free to rotate on the chassis as fixing them may impede location points of the cargo bed framework in a later step.

• When adding the fuel tank bracket parts D41/42/43 & 44 in step 5, I recommend building up the whole fuel tank shown in step 7 first. It can be used as a template to assist in getting the brackets to locate correctly on the chassis rails.

• Part A22 in step 7 is asking to be damaged if fitted in this step. It can be fixed in place just before adding the front fender moulding shown in step 16 if you wish.

• For attaining the perfect track tension in step 8, it is advisable not to glue the idler arm mounts (parts A18 & 20) into the chassis as per the instructions. Wait until after you test fit the tracks. It is also worthwhile adding both idler wheels onto the idler arm mounts first and allow the glue to cure, as the location points are very shallow.

• In step 9 it is not essential that you add the steering column to the chassis, but it must be added before the bulkhead assembly in step 26 if you want to display a full column (it can be seen if the driver's side engine panel is positioned open). If the engine bonnet/hood is to be fitted, and the side panels are to be positioned closed on your build, the steering column can be safely cut in two around the centre point if you wish. This will leave the top half connected to the upper cab assembly and the lower half connected to the chassis. Adopting this method of creating sub-assemblies makes things a whole lot simpler, especially if you want better access to airbrush the cab interior. The lower half of the column with the steering box must be added to the chassis to allow the steering linkages (shown in step 11) to be added. The top half can then be added to the bulkhead assembly and fixed onto the instrument panel with the photoetch brackets. Spacing is easily worked out for adding the steering wheel at the correct height. 

• Also in step 9, the double wheel stub axles (parts 29) are a decent friction fit into the chassis, so leaving them unfixed will allow articulation of all the track wheels so they can sit naturally down on the tracks if displaying the vehicle on undulated terrain. If you do wish to display the tracks sat on a perfectly flat surface and are tempted to glue the track wheel stub axles in place in this step, don't!  The front wheels must be test fitted first. With the front wheels added it slightly raises the front of the chassis. This confirms the fixed static angle that the stub axles need to be fixed at if you wish the vehicle to be displayed on a completely flat surface.

• In step 10 the front wheel hubs can be angled but the engineering is very sloppy and loose, making the wheels droop severly downwards and inwards! Shims can be added to stiffen things up but it is far easier to simply choose an angle and fix them in place. Please note that if you do choose to angle them then the positioning of all the steering linkages to the steering box must be adjusted to suit. The positioning of these linkage arms (displayed with the wheels at the straight-ahead position) are in the line drawing shown in step 11. 

• The sprockets are built up in step 14 so the fix found here will need to be made to ensure good track fitment.

• Before adding the front fender moulding (part WA4) in step 16, remove the large nut detail that are added over the three dome shaped rivets at the lower front of each fender. The domes should be present, but the nuts should not. Trumpeter has mistakenly referenced an incorrectly restored vehicle. It is also worthwhile adding the exhaust parts before the tracks in this step, as a fair amount of handling will be required.

• Good clean up of parts WB1/WB1/WB5 & WB6 is essential in step 17 as these dictate spacing between the bulkhead assembly, the cab floor, the chassis, and ultimately the final position of both the bonnet/hood, and all the engine panels. They are quite crudely moulded, and the location points are far from precise. Plenty of test fitting of all these components is required to get the best fit once final sub assembly connections are made in step 26.

• The angle that parts WA1 and WA2 sit on to the underside of the cab floor in step 18 is not at all obvious, as the location holes are very shallow. Once the cab floor is added they should sit slightly inwards of the centreline of each chassis rail. There are no location marks so keeping them equidistant will ensure the cab sits square on the chassis.

• Following the instructions and adding the cab floor  to the cargo bed assembly shown in step 25 can make fitment of this whole sub-assembly to the chassis tricky. As there are no precise fixing points for the cab floor the only visual alignment clue is via the stepped track guard connection to the front fender moulding. If anything is slightly warped on the multipart chassis assembly and is not 100% straight then the cargo bed fixing points will not align, making the whole fixing process frustrating. I've always found adding both cab and cargo body separately a preferred method. Both parts butt tightly up to each other anyway.

• The fender support brackets (PE-WA10 & 11) do not fit the contoured detail on the underside of the fender moulding very well, so they will have to be manipulated and bent to fit!

• If not wanting to display the engine I would recommend building up the radiator housing and engine panels shown in step 29 as early as step 17. Use them as a template for getting the best alignment of all the other cab sub-assemblies. The one-piece armoured cab moulding comes in handy for this purpose too.

 

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