BP Models

Build log for Dragon kit #6540 Sdkfz 161/4 2cm Flakpanzer IV Wirbelwind with Atak zimmerit, MK SK-17 workable tracks, and RB Models turned aluminum and brass 2cm Flak 38 L/65 barrels.

Work is officially underway with this build effort. Step 1 has been completed and deals with the usual first step requirements, the road wheels, idlers, sprockets, and return rollers. I left the road wheel halves separate to facilitate their painting later on but each one had the molded-on seam (accurate if you wanted to show brand-new wheels) removed using a sanding stick. The step includes the option for two different types of steel return rollers featured on the Pz IV H (but not the G) and I opted for the "fancier" type for pure variety's sake. The step also provides a choice of idler types between the earlier tubular style and the later cast style. All of the pics I've got to hand for the Wirbelwind show that the tubular style was the most commonly. That's logical given that the hulls available in 1944 would most likely have been produced before the switch-over to the later cast style idler, so the tubular parts were used.



That's as far as things will get this session as the next few steps deal with the various parts of the lower hull and those will need zim panels as well as their normal details/assembly, so that will have to wait until the next session when I have a good enough block of time available to tackle that.

Some good progress this weekend, work continued on the lower hull with Step 2. This step deals with the rear hull plate and calls for the mount holes for the standard turret traverse motor exhaust to be filled with putty and the two retaining strap bolts removed. I didn't bother filling the holes since I'm applying the Atak zimmerit but the bolts were easily removed with a sharp #11 blade. The rear plate received the blanking plate for the exhaust pipe exit and the Atak zim strips were added using Gator Grip glue and strategic amounts of liquid glue applied around the strip edges to insure they tacked town cleanly. I also assembled and installed the rear towing apparatus and based on previous build experience with DML Pz IV family kits, I installed the crank starter port (parts H25 & H24) that aren't called for until Step 5 as it's easier to add them now vs waiting until later.



Step 3 calls for the rear plate to be added to the hull tub along with the nose plate. The rear plate installs easily without any issues, just some finger pressure required at the edges to get a good join. Also be sure to remove the large stubs on the top edge of the hull tub at this point as the instructions don't indicate this is needed and they will interfere with the fit of the fenders later on.

The nose plate has a sub-assembly involving the front tow pintles. I've found that it's easier to install the base plate for these, part A27, directly to the nose plate and then add the angled hook parts A33/A32 after it has set vs assembling the tow pintles off the vehicle and installing as a single part. It's also easier if you add the tow pin A30 to the angled hook parts before you glue them in place on A27 since the pin fits very tight and can break easily if you're not careful. Once the tow pintles were mounted, the Atak zim panels were added to round things out.



Step 4 starts work on the suspension elements but before tackling that, the Atak zim was installed for the lower hull spaces on both sides. The panels fit well and just needed a small amount of trimming around the bump stop mounts and the return roller mounts here and there to sit down properly. Once the panels were dry, I added the final drive housings along with the suspension bases and rear tow hooks. The suspension bases are "keyed" to avoid accidentally installing them on the wrong side, a nice touch IMHO. The bump stops were a two-part assembly and I elected to install the frames for the stops directly to the hull and then added the rubber bumpers vs. trying to assemble them together and then installing.



Work will continue on the lower hull and suspension as there are still several more steps to go for this portion of the build.

Real life activity has a tendency to interfere with getting solid bench time and it's hard to believe that this one has sat for nearly a month, but there you have it! Between travelling for work, having to take care of the usual spring-time yard work, training a new Boxer puppy (who has grown 25% by weight in just 4 weeks!), and of course the rest of daily activity and the month has just flown by.

Fortunately the Easter weekend afforded me a chance to spend some more time on the Wirbelwind. I picked up where I had left off with the lower hull and continued work in this department with Step 5. This step adds details to the rear hull plate in the form of the idler mounts and tensioning housings as well as the engine muffler/exhaust. I had to do a bit more trimming of the zim around the ports where the exhaust pipes exit the hull in order for the armored trays to sit correctly but easily done using the tip of a sharp #11 blade.



Moving on to Step 6, I assembled and installed all of the lower suspension bogeys on both sides of the hull. The fit on these is slightly tricky and it is important of course that all 4 bogeys line up properly on either side to avoid problems later on. I double checked everything on a level surface and also used the old trick of lining up all the mount arms by eye instead of relying only on the "sit" of the bogey mounts.



Step 6 also calls for the installation of the glacis plate. Since I'm creating a vehicle with zim, the Atak set provides a resin replacement piece that is a "clone" casting of the kit part plus the zim pattern. The set actually includes 2 plates (one fully zimmed and one with no zim around where the spare track run mounts) but the one with no zim was cast too thin and irreparably broke when I was trying to remove the pour plug, so the other plate was used instead. The brake hatches and armored vent covers are also provided as separate resin parts and these were installed using CA gel.

The set also includes a nice little thin zim strip to cover the hull nose plate top surface that sits flush with the glacis, this was added with the help of Gator Grip glue and some liquid glue around the edges to round things out.



Hopefully it won't be another month before I can get some more bench time in on this project and will be able to pick up some steam in the coming weeks.

Happy Easter!

More progress to report with this project, work continued from last week with the lower hull and Step 7. This step is the standard Pz IV set that adds the fenders to the lower hull but it's to your benefit to skip ahead a bit and first add the lower hull insert part D13 called for in Step 9 as it is much easier to add it now along with the firewall part D16 vs. waiting until after the fenders are in place.

The fenders need some work before they can be installed since they have the molded on schurzen mount posts for a standard IV-H that need to be removed. This is easily enough done with careful use of sprue cutters and sanding/trimming with a #11 knife, just be careful not to gouge the fender edge in the process.

Since I'm adding zim, the portions of the front and rear mud-flaps were given the necessary Atak panels although some modification was required on the front mud-flaps to remove enough on the lower portions to allow them to clear the front hull properly. The same is true of the panels added to the lower hull in the earlier steps, a consequence of the fact that the zim adds a fractional additional thickness to those areas that the DML part design tolerances don't allow for. It's not a big deal since those areas aren't visible after assembly but it is something for others to be aware of if you choose to use the Atak set.

I skipped Step 8 for a bit since it deals with assembly of portions of the upper hull and proceeded directly to Step 10 which adds some of the hull bracing and Flakvierling base mount parts. These were assembled and installed without issue although I didn't glue done the "arms" on part D24 just yet as I want to be sure the fit with the upper hull is correct when I add that later.





I had hoped to get the rest of the upper hull done but working with the fenders took more time than I anticipated, so the upper hull will have to wait until the next bench session.

Today's efforts proved just how delusional I was last week when I thought I could get the upper hull done along with everything else accomplished in a single day! I spent the full day working on this area and after some careful study decided the best way to go was to assemble the superstructure first and then add the zim panels.

That meant doing things a bit differently from the instruction order and involved combinations of working through Steps 8 and 11 to get to the desired end result. The Atak set includes a resin replacement for the superstructure front plate and is a dead ringer for the kit part. I took a short-cut with the hull MG since I wasn't intending on displaying the hatches open...instead of doing the full 7 part sub-assembly called for, all that is needed is the actual barrel part j28 which was inserted into the ball mount part G32 and secured in place with the exterior armored cover part E14. The MG is still movable which will come in handy for detail painting later on. I also installed the armored glass insert and used some poster blue-tack putty to mask it off.

Both of the side panels were added using regular glue and a combination of finger pressure to get a good fit followed by careful application of liquid glue along the top edges where DML had molded some excellent weld detail to insure a seamless edge. The front plate was added using CA gel after test fits to make sure everything stayed square.

A small detail worth noting at this point in relation to the superstructure, there are several faintly molded-on locater lines for the schursen mount tabs that would ordinarily be found on a standard IV-H hull and these needed to be carefully removed however the instructions make no mention of these at all. In some of the later step diagrams, you can see these small tabs in place as a "legacy" from the diagrams used in the IV-H kit but they are nowhere to be found on the sprues. Since I'm applying zim, the holes on the superstructure side plates where these would mount are already getting covered up, but if you aren't doing a zimmed vehicle, they would have to be filled with putty. You can see the small tab holes on the rear engine deck that had to be filled as a case-in-point for reference.

Then it was time to zim! The resin panels were added using a combination of Gator Grip glue and liquid glue to tack down the edges and this of course added to the assembly time because there are so many panels to add. The Atak set includes resin replacement parts for the armored ventilation cover on the driver's side as well as replacement crew hatches with zim. These were glued in place with CA gel to avoid them coming loose in handling during later stages.



I also applied the zim to the rear deck plate and installed it to the superstructure. The Atak zim panel didn't include holes for the three spare track link holders commonly seen here so I opened those up carefully using a pin vise and drill bit. The air intakes were also added to the superstructure to round things out prior to installation.



Installing the superstructure to the lower hull is a tight fit and I'm glad I left the front bracing arms loose on the hull insert part D24 as having just that little bit of flexibility was enormously helpful. Overall the fit was good with the lower hull but some help was needed with a couple of rubber bands and finger pressure to get a good join particularly at the rear hull.



Once the join had set, the bands came off and the engine deck hatches were added. These were almost a friction fit and only a small amount of liquid glue was needed to secure them in place. I also added the rear antenna mount called for in Step 12 as I wanted to be sure it wouldn't require any more zim surgery and it fit perfectly. I was going to use the base part from the kit-supplied antenna part E19 but the carpet monster claimed it so I had to go to the backup plan and use the base of part K2 which was marked as not for use. The antenna portion was cut off and the top drilled out with a #76 finger drill in anticipation of mounting a brass 2m antenna later on.



Next up will be a little work on installing some of the fender gear and then it will be on to the Flakvierling and the turret.

I had the day off today for the Memorial Day weekend so was able to get in some good bench time as well as last Sunday to produce the latest update progress.

My efforts focused on Steps 12 and 13 which deal with all the fender gear and equipment. For the left fender, I installed the fire extinguisher, the base for the C-hooks, and Bosch head light. The Bosch light is missing the wire conduit that connects the light to the hull glacis plate, so this was added using 0.5mm diameter solder. While the kit tools come with molded on clamps with open handles, I opted to replace those with Griffon clamps instead for better detail and the only clamp on this fender is the one for the wire cutters. All the other tools were left off and will be installed later.

I opted for the tubular style of rear convoy light and left the clear insert off for now. I also chose the styrene one-piece option for the hull air intake covers and added the wing-nut retainers courtesy of parts A58 that aren't called out on the instructions but which are there on the A sprue. The instructions contain a small error on the spare road wheel box, the call-out box indicates that separate parts E41/42 are needed to complete the box but those parts are already molded on the box provided and don't exist on the E sprue! I also had to trim back a small corner of the hull roof Atak zim panel so that the box would sit at the right height and level and also removed the small tabs on the back "feet" of the box as they no longer aligned with the openings in the fenders due to the hull zim added thickness.

Last but not least, I also added the spare Flak barrel boxes and the instructions have a serious part mis-label problem for these. The correct left side supports are parts D3 and D4 not B3 and D6 so be careful here to get the right ones on each side. The boxes themselves aren't assembled and added until Step 21 but I added them here as I lost the locater points for the supports when the zim panels were added and it's critical that the supports be in the right place/alignment.



The right side fender took more time because it has more tools with "standard" clamps to deal with. The front fender zim was trimmed slightly to allow for the kit-supplied PE axe holder to be installed with CA gel. Griffon clamps were used for the axe, the starter crank, and the shovel and the jack was added in its designated place. The hull intakes got the same treatment as the left side as well.

The spare barrel box for the right hull side has an added detail in the form of spare antenna racks and 2 antennas, so the mount assembly here is a little trickier than on the left side. The instructions have the mount parts here wrong as well, the correct parts are D5 and D6, not D4 and D5, something easy to figure out when you actually look at the parts in relation to how the antennas are mounted. The kit supplied antennas have multiple "nodes" and sprue connection points so clean-up requires some care, but they fit beautifully into the base mount rack.




More progress to come later in the weekend I'm sure as I have three more days of opportunity to continue work. Next up will be the Flakvierling.

Holiday weekends are perfect times to build and work continued yesterday and today and focused on the Flakvierling. Step 14 begins the assembly and deals with a lot of parts and sub-assemblies, so it's best to give it some thought first as to the order of things (as well as look at Steps 15 and 16 to make your life easier) before diving in.

I assembled the 7 part sight apparatus first and decided that it would be best to set this off to the side and install it after the whole gun was assembled in order to allow the sight to remain movable along with the guns. This sub-assembly involves several parts fitting together "puzzle piece" style and I found that starting with the base mount part A36 and working my way outward from there was the best way to tackle it. I also drilled out the telescopic ground-target scope with a #76 finger drill for the eyepiece end and a #80 finger drill for the opposite end to add a little detail.



The rest of the base was assembled without any real issues, the only modifications called for in the sheet were to trim down the standard ammo racks, parts A31/32, so that they would fit properly inside the Wirbelwind turret. This was accomplished with side cutters and some light sanding to smooth the edge out. I went ahead and added the inserts, parts G13 now even though they are called out in Step 16 as it's easier to assemble them before installing the racks onto the gun base vs. later.

I also opted for the styrene gunner's seat base instead of the PE adjustable parts as I didn't have a need to pose the seat and the styrene option was the simpler choice. Care does have to be taken when adding the top and bottom halves of the gun assembly to insure part A48 remains able to rotate so that the guns can also move later on.





Step 15 adds the semi-circular mount plates for the four Flak 38s along with the guns themselves but it will be much easier to paint and detail the guns off the mount, so I will install those later. The mount plates were carefully added with sparing use of glue to insure they remained fully movable and allowed to set. The connecting arm A45 was installed and then hooked up to the gun sight arm/mount. The mount pin for the gun sight arm, part A54, has a good friction fit and doesn't require glue to stay in place and remain movable once the connecting arm is hooked up. The instructions would have you glue this into position but it's far better for detailing access and to be able to pose the gun to leave it movable IMHO.



There was something nagging at me about the gun-sight and after checking my references, I figured out what it was. DML molded the rear portion of the aperture solid and it should really be an open ring...so I got out the pin vise and micro-drill bit and opened it up. Now the gunner could actually "see" what he was aiming at!



Next up will be the necessary surgery to replace the kit barrels with the AM aluminum/brass combos from RB Models and then the turret assembly and details.

Having come from a military family and background, it's particularly important to me to acknowledge that today is not just another 3-day weekend but is a day for remembering those who gave the ultimate sacrifice in service to our country both at home and abroad. Without such brave men and women answering the call across multiple generations, it would not be possible for us to enjoy the freedoms we do today.

Today was a particularly productive day at the work bench...the weather topped 100 degrees outside so I had the perfect excuse for staying indoors. First order of business was to work on the Flak 38s, so I returned to Step 15. The kit supplied parts are highly detailed but the one area that styrene limitations really show is in the flash suppressors on the gun muzzles. While DML molds the openings hollow, the slots on the neck and the holes in the sides are only molded as slight depressions. So I turned to my trusty source, JB Models, for some turned aluminum and brass replacements. The aluminum barrels come with separate brass suppressors and the opening in the suppressors needed to be opened up slightly with a round needle file to fit the barrel neck but otherwise assembled without any problems with a little CA gel. JB Models produces don't come with any instructions, so you need to be ready to figure things out on your own. The small PE fret included the barrel release catch and this was added with a small amount of CA gel as well.

The styrene kit barrels were cut away from the receivers with sprue cutters and then the ends sanded down with 400/600 grit emory board to the right length. Using a sharpie, I blackened the ends (this allows for easy determination if the hole being drilled is centered or not) and then used a pin vise and drill bit to create the required holes to accept the mount pins on the end of the aluminum barrels. The barrels were then joined to the receivers using CA gel and the rest of the gun assembly completed with the addition of the top housing and locking bolts and 2.0cm magazines.



Step 17 deals with the turret and assembles it from the two shell halves plus the circular ring insert. I found it was much easier to install the ring insert first and then add the rear half after as it provided more surface area to glue and work with in terms of getting the rear and front halves to mate up correctly. I glued the base of the rear half first and let that set up, then worked one side at a time with liquid glue to insure a solid and square join on all sides. The front direct-fire flap was added (it's part D17, not B17 as called out in the instructions) along with the hinge parts, D19, which the instructions don't provide a parts number for and just show already installed. I opted for the closed position and installed the two PE retaining clasps using careful amounts of liquid glue to secure them in position.



Step 18 adds the turret interior details. I installed the two loaders' seats but only added the base parts for the ready ammo racks. The additional parts to complete the racks have the magazines molded together so for detail painting purposes those will get added later. The backs and bases of the racks had large shallow ejector marks that would be partially visible after assembly so a little bit of sanding work took care of them.



Step 19 wants you to add the Flakvierling directly to the turret, that will get done after painting so that was skipped for now. Step 20 directs you to add the PE supplied spent shell casing collection chute but you can do this at any time as the installation doesn't interfere with the fit of the Flakviering with the turret...I think DML left to this point as it was the most convenient spot for it and/or they forgot to mention it in the earlier Steps dealing with the Flakvierling. The PE part doesn't have traditional bend lines but instead has perforations which makes for a sharp bend on the first attempt but don't over-do it as bending it back will make it fragile and possibly damage/break it in the process.



Step 21 is the final step, it shows the install of the turret to the hull as well as the addition of the tracks and spare road wheels. The tracks will come later after painting as will the road wheels. The diagram shows the base of the turret ring, part D22, installed in place but doesn't call it out with a parts number so be sure to add that so that the turret will sit correctly. I did a quick test fit to make sure everything would play nice with each other and the fit is snug but perfect.





Aside from the MK tracks, major construction is at an end and will be moving into the painting stages as the next step.

Hard to believe it's been 6 weeks since I was able to get in any more progress on this project! I've been repainting the interior of my house and that consumed a lot of weekend time as did recent projects at work so the Wirbelwind got put on hold as a result. Fortunately I was able to get some work done on it this weekend and post an update.

The last frontier before painting was the MK replacement workable tracks so I set about getting them assembled. Each MK set has its own characteristics but this particular one had 4 links per sprue, each with three contact points. The links were removed from the sprues and cleaned up, working in sections of 8 links at a time using the provided jig in the set. Since the tracks are "handed" there are two different types of pin for the inner and outer sides of the track runs and they come on their own handles for easier installation. Just touch a bit of glue to the head of the pin and insert using the jig. Let dry for a bit and then just twist off the handle and voil�! you have a set of 8 workable links.



After rinsing and repeating that process, I created 2 track runs of 96 links each over the course of about 4-5 hours of work. Once the hull is painted and the suspension is on, I will need to add 2-4 more links depending to get the sag I want but will old off doing that until later to be sure.



Hopefully I will be able to get some time in the coming week to start the paint process and get this one back on track for completion.