The
German "SPAT" GUN

Self-Propelled Anti-Tank Gun

The German spat?  I hope he didn't hit ME!

Here's yet another GI JOE vehicle project -- this time centered around the M5 Stuart chassis.  Back when these went on clearance, I was fortunate enough to pick up an extra 27mhz tank.  The chassis went to GIDefender for an AT project, and the shell became the basis of this project.  I decided that having a German hull and the regular M5 hull meant that I could swap the chassis back and forth depending on whether I wanted to use a German or American tank.  I also picked up a 49mhz tank that will remain an M5.  By using this hull on the 27mhz chassis we can do battle between this and t he 49mhz camo M5 in the back yard.  Fun! 

 

Choices

Now I had a spare hull, but wasn't sure what to build on it.  I wanted a German tank of some kind, but wasn't keen on scracthbuilding a turret.  Besides, an open top (like the White Scout Car) would offer greater play value.  Thus, I decided on a German Self-Propelled artillery piece.  GIDefender donated a 75mm cannon from the back of a Hasbro halftrack, so the rest seemed to be destiny - the only remaining question was what shape to make the tank?

The Italian Semovente M40-75/18 had promise.  It's an Italian tank (in this pic it has German markings) that was small enough and was easily do-able, but one distinct characteristic of this self-propelled gun is the suspension.  The M5 suspension would require too much modification, and I wasn't keen on messing with the chassis if I could help it.  I had to find a design that would look ok with the Stuart bogie design, even if it wasn't especially accurate from a historical perspective.

 

 

I ran across the Wespe self-propelled field artillery piece.  This looked like it might be a player!  The suspension was 'way off, but the hull met my criteria for open-top play value!  I liked the lines and its size, too.  This looked like a good model for my project - at least as a starting point.  Note the really groovy driver's hatch.  With no hull machine gun, it'd ease my building time, too!  I thought this might be the way to go.  I'd be using a 75mm Anti-Tank gun rather than a giant howitzer-type gun, but it still might be cool.

 

 

 

 

 

I ran across some uglier designs, too, like this German Marder II SP AT 7.5cm gun.  It was one ugly beast!

The SP Howitzer "Hummel" (Bumble Bee) was even bigger with a longer chassis, bigger gun, and larger fighting compartment.  These Germans made some ugly tracked vehicles!

 

 

 

During my research, thinks went from bad to worse.  The Bison AusfH (left) was pretty awful-looking.  It had a HUGE fighting compartment and looked awfully heavy.

The SdKfz 138/1 Ausf M "Grille" was based on the Czech chassis (used by the Germans as the 38t) and was a better design, but not a lot of room in the fighting compartment.

The positive learning point here is that I could possibly create my OWN design and it'd look passably authentic... it couldn't look much worse than some of the tracked guns the Germans REALLY fielded!

 

 

At right is the 15cm PzKpfy 1 AusfB.  It's one ugly field piece.  My goal of a believable-looking armored vehicle was going to be easier to obtain than I thought!

It got easier after some further research.  The Germans used captured vehicles whenever they could.  At left you'll see the 3.7cm antitank gun mounted precariously on an M3 Stuart chassis.  Hmm... if this kind of an ersatz AT gun was fielded, I could probably build whatever I wanted on the M5 chassis and it'd be plausible (especially as a toy rather than as a historical model!). 

The plan started to come together...

 

 

 

 

 

The Adventure Team Commander's
German SPAT Gun

"SPAT"  Self-Propelled Anti-Tank gun.

The Chassis:

Back when I did some modification of my first M5 Stuart, I had moved the battery underneath and moved the radio forward on the front firewall.  Details can be found at http://gijoe.50megs.com/StuartMods.html (on that page you can see in great detail what I did and how I did it).  Here is the pic of the chassis, prepared to begin THIS project.  The charging jack has been added to the rear of the tank, the battery was relocated underneath, and the R/C radio was moved to the front firewall.  This opened up the “fighting compartment” nicely.  I left the speaker where it was, as I figured I’d add a fake floor there anyway and it could rest upon the speaker for support.  I’d done all of this a long, long time ago knowing full well that eventually I’d make a Priest, Kangaroo, Recovery Vehicle, AT Vehicle, Lost in Space Chariot, or SOMETHING out of this groovy chassis!    Thus, the only remaining challenges for this project were final interior touches as well as designing and building the shell or "hull" to put on the existing M5 chassis.  I made some “sort of” goals to add a driver’s seat, ventilation, a hull that looked like something the Axis would field, and then would add details (crew and interior stuff) to finish it off.

 

The Driver’s Seat:
First, I decided I needed a driver's seat.  In addition to needing it for this project, I also wanted to use the same chassis as the basis for a Australian “Kangaroo” that’d need a driver, too… making the modification now will help this project AND be already in place for the next!  I wanted a single seat in the hull and an offset driving compartment like on the Wespe (see the pic in the second paragraph at the top of this webpage).  To that end, I needed to find a Joe that was flexible, light, and would look ok in that position.  The CC and SA Joes seemed heavier and clunkier, whereas the vintage-style would squeeze in and out more easily.  I chose "Carl", and Elite Brigade figure from Cots.  This guy looks like James Cagney, only in blonde he looked like a tough, wiry, non-nonsense Aryan tank driver.  Using the figure as my measuring device, I epoxied some seat runners over the port-side engine and built a seat to slide into position.  Here you can see how easily this was to install.

Here you can see the driver’s seat.  Thanks to the gearbox, his legs are angled a little off-center, but it still worked fine.  Reminds me of the test drive I took in a Jeep Cherokee once… the pedals were offset to make room for the wide center transmission hump - felt like I was sitting crooked.  I had more leg room in my Toyota Tercel (no, I didn’t buy the Cherokee).  Anyway, this setup works well for Joe in the driver’s seat.  It provides protection of the gears (to keep his pantlegs out of the way, and keeps his butt off the hot engine.  Playtesting will reveal whether it’ll get hot enough to melt that soft styrene plastic or not.

 

 

The Hull Surgery:

Next I built the hull up into the shape I wanted.  That meant using a Dremel tool to change the shape of the front of the glacis plate.  As you can see here, I took off everything I possibly could, including the lights, brush guards, machine gun, spare bogie, etc, and began cutting with my trusty Dremel.  You’ll note that I cut straight along the sides rather than matching the existing seam.  This will give the finished product a straight slant to the front glacis plate rather than that “hump” the M5 has along the front line of the hatches.  My hope is that the straight glacis will look more slanted and “Panther-ish” than the M5s abrupt angles.

 

I had to open the deck up, too.  Here I cut along the top edge of the Stuart hull, and I made a straight cut along the rear sides rather than leaving the “hump” where the oversized engine compartment was formerly located.  I tried to leave as much as I could where it was necessary to fasten the hull to the chassis or otherwise for support.  Here you can see how much I cut away from the front and from the top deck.  It’s also apparent where I gave the hull straight sides instead of the engine “hump”.  Cutting this black styrene with a Dremel is very messy work, by the way.  If you plan on doing this, don’t do it on your kitchen table where bits of molten black plastic will fly into the living room and land on the carpet.  It will probably make your spouse angry when she gets back with groceries and sees what you’ve done.  Rather than be proud of you for your ingenuity and your efficient, clever solution, she’ll more likely harp and crab at you until you vacuum the living room and wash the kitchen floor.

 

The Cannon:

Next came the cannon.  GI Defender sent a 75mm cannon my way and it would be perfect for this project.  I was planning to use the Navy 40mm pom-pom guns, the 37mm Hasbro AT gun, a vintage 5-Star recoilless rifle, or the big ol’ Howitzer cannon, but this 75mm gun looked like it’d be better than any of the other choices!  I used the guts from the M5 Stuart tank turret and mounted them underneath the cannon base.  This took a few minutes in the garage on the table saw to rough out the shape.  Then I used a belt sander to do the final shaping until I got it the shape I wanted.  I used the gears and gearbox from the M5 Stuart and simply screwed the big turret gear to the bottom of the 75mm pintle.  It worked great!  I wasn’t able to exactly center the gear on the pintle, and when I rotate 360 degrees there’s a point where it won’t traverse any more because the gears don’t mesh deeply enough.  For my purposes, however, I only needed a limited traverse for an AT or Field Artillery gun, so this solution would work fine for this application.

 

 

After I mounted the gearbox, I had to fit it to the chassis.  I did this by cutting sheet styrene to fit the base of the 75mm cannon and across the width of the hull.  The gearbox stuck out toward the driving compartment.  In the pic at left you can see how I did it.  Later I added some vertical supports made of styrene.  This held the gun firmly in place without being glued down.  It was important to ensure that everything was easily removable, since I intend to use this hull for other projects later.  My Master Plan is to use this hull with several hull bodies for various purposes, thus maximizing play options while minimizing storage requirements.

 

 

 

 

The Interior:

During the time I was working on the cannon, I was also working on the interior.  I seldom do just one thing at a time because I get bored waiting for glue to dry and usually begin another aspect of the project.  Here’s the interior in its infancy (at right).  Here I added the brace for the cannon and also added a rear seat.  I tried many different types of glue in this project and had some abysmal results from Gorilla Glue as well as some others.  JB Weld and good ol’ 2-part Epoxy (Loc-Tite) were the winners for this project.  Here you can also see the fake floor I put over the rear of the speaker and across some screw-points that were made to hold the R/C board that I moved up front.

 

 

With the R/C radio on the firewall in the engine compartment, I didn’t want any more heat than necessary in the forward compartment.  The seat I added for the driver would probably not help, neither would a figure up there.   Thus began my quest for a way to cool the enclosed compartment.  Like lightning, a solution suddenly appeared!  Our house took a lightning strike and blew the snot out of a computer power supply.  Just for fun, I tore the old power supply apart to see what was inside (I often do that with mechanical stuff due to my never-ending curiosity and need to know how stuff works).  Inside I found a cool little fan that ran off 12 volts.  I applied power and the fan still worked, even though the power supply was dead.  Hmm... the gel cell that powers the Stuart is also 12V... it looks like I found myself an M5 engine ventilation solution!  You can see in this pic how I installed the fan.   I used a piece of metal strapping from the junk box in my garage and just bolted the fan to the strapping and to the floor of the M5 chassis.  12V is running all over the place in the engine compartment, so findind 12VDC isn’t very difficult.  I used the main power lines to the R/C radio board (the wires fit nicely in the backside of the male connector running to the PC board.  The power for the fan runs directly to the power source to the tank, so whenever the tank is on the fan is running.  I drilled as many holes as I could in the the hull for ventilation (in the pics you can see the holes… the new armor leaves a little room for airflow and the holes I added to the original M5 hull beneath match up with the fan location).  I would've opened up a gaping hole for fan access, but I wanted something to protect the fan blades if I ran through grass or sticks while on patrol - thus I drilled lots of holes to make a redneck “grille” over the fan.   

 

The Hull Front:

Mounting the cannon wasn’t a big deal, but getting it through the hull is a bigger challenge.  I tried all sorts of approaches, even going so far as to try two different sized plastic flower pots, figuring that then I’d have a rounded spot on the hull for the cannon to stick out while giving it room to spin as the cannon rotates.  All of my different experiments were failures, but the final one seemed ok, so I went with it.  This final experiment used a simple sliding window approach to permit the cannon room to move.  I mounted a couple of runners along the backside of the front armor plate and trapped a flat sheet of styrene by gluing on the backside of the runners.  A picture is worth a thousand words, so see the pic and you’ll see how I did it.  The cannon itself pushes the movable “window” from side to side as it rotates.  This minimizes the size of the hole needed to let the cannon protrude.  I intend to make a canvas-looking cover to snap onto the hull and around the base of the cannon to hide the hole anyway, so this was probably a lot more hassle than it needed to be; but I enjoyed the engineering challenge despite the unnecessary nature of this feature!

 

 

 

The Hull Body:

Unsure what final design I wanted, I made a few cardboard mockups to see which I liked best.  Here you can see the cardboard mockups I made.  At left is the more cutaway design and at right is the blockier more full-coverage design.  If you look closely at the pic at right you can see the line indicating the difference between the two.  I actually made a removable armor template piece that slid on and off so I could compare designs.   Although the more open “Marder-ish” design looks cool, it doesn’t look as good when crew are lounging around inside.  The more enclosed version at right looks cooler with crew.  I think  I’ll go for the more enclosed version, but perhaps I’ll leave the back somewhat open so it’ll be easier to get stuff in and out (and will have more play value, too).  Besides, if the side armor is bigger, there’ll be more room for a big ol’ German cross for the Stuart to aim at!

 

I couldn't figure out what shape to make the hull.  I lingered over this decision for a long, long time until I finally just started cutting out cardboard shapes.  It took a while, but eventually I found a shape I really liked, was do-able, and looked somewhat authentic.  Above and at left you can see some of the different shapes I toyed with before choosing a final winner.

The ultimate shape doesn't look anything like the above pics... I ended up going after the shape at left with a razor knife and kept trimming it at different angles and shapes so it was practically gone by the time I was finished.  The process was valuable, though, because I passed one version in the process that I really liked -- and that was the one I ended up using.

You may have noticed that the armor plate is angled differently than the M5 Stuart’s armor.  The Stu has more vertical armor, whereas this is more angled.  The beauty of this design is that there’s enough room under the front of this armor for me to stick a finger in there to dig out mud or debris - and there’s also plenty of room for ventilation access to the fan.  I have yet to decide on whether to give it a driver’s hatch or not.  I originally built the driver’s seat with the intention of adding a Wesp-ish driver’s hatch, but after adding the front armor plate, I was unsure.  I really liked the long sloped front, but it’d still be cool to have a driver’s noggin sticking out.  Since I’ve already got the driver’s seat inside, it’d be an easy enough proposition to cut a hole in the front glacis and scratchbuild the sloped armor to add the hatch.  Hmm… decisions, decisions!  

 

 

During the cutting and fitting phase, the crew had to try it out.  The Dragon tank commander and gunner checked out all the various areas for habitability and minor adjustments were made to accommodate the figures.  I wanted them to look a certain way when the hull was finished and tailored the hull to match my capricious expectations.  For example, I wanted a certain level of "bend" in the commander's elbow and a a height that would be appropriate for crew in the back to hang an arm over (in case they want to drive slowly through a French town and pick up chicks).  At left is a stage in building before I arrived at the final shapes.

 

Below, you'll see below what hull shape I FINALLY decided upon.

 

 

 

Finished Product:

Here's a look at the finished AT gun.  At the time of the pic, they were on patrol to find out who knocked over some of the HausFrau's walkway lights and tossed them into the shrubbery.  These resistance fighters are a constant nuisance to the HausFrau, and the German AT Gun crew is here to put a stop to it!    

This pic clearly shows the color mismatch between the old chassis and the new hull.  Since this chassis is STILL the undercarriage of my M3 as well as this German gun, I decided not to paint it.  Soon it'll be the basis for a Canadian "Kangaroo" and/or 105mm Howitzer tractor, so I really don't want to repaint it.  

 

 

 

Here' s the interior.  I used a darker grey on the outside and a lighter shade of grey on the inside.  In the goofy light here, it looks white, but it's really light grey.  If you look closely, you'll see that I gave the floor a "splatter" of paint to make it look worn and dirty from their combat boots.  This pic also shows the gun mount a little better.  I picked up some brass at the local shooting range that fit the ammo storage slots (not shown).  I forget what caliber they were, but they had a rim (like the plastic Hasbro shells) and the brass cases slid nicely into the storage holes beneath the cannon.  These pieces of expended brass will also be cool in a diorama, as I can toss them on the ground behind the vehicle - where the loader heaved them during the reloading process.  Plus the brass is dirty looking, so it adds to the realism a bit.

 To the right you can see a shallower angle rear-view with the hatch open.  

 

 

 

 

 

 

Here's the loader checking on the fuel cans.  This pic shows the spare bogie wheel attached to the rear hull, the antenna mount, extra track links, and the fuel can rack.

The bogie wheel came from the front of the original M5 Stuart's hull and already had a couple of mounting screws.  I glued a sheet plastic mount to the rear of the hull with a couple of "keyhole" slots to slide the screws into.  Sort of like hanging a picture, just insert the bogie wheel's screw heads into the fat part of the keyhole and slide straight down.  It's neat and secure. 

the spare track links came from the turret of the original M5 Stuart.  I painted them black and made a slide-in rack for those, too.  To remove, just slide the link section straight up and it pops off the rack.

The gas can rack was made by simply lining up three gas cans and cutting out a rectangle of plastic with the same "footprint".  Then I built up the sides and front, and glued the whole thing to the rear hull.

You'll also notice the rear hatch on this vehicle happens to be the battery door (engine cover) on the original M5 hull.  The hinges worked great!  I also re-used some grab-handles and other little odds and ends.  It's recycling!

Finally, the antenna mount has been lifted from the M5 turret, too!  It fit in that spot very nicely and looks like it really belongs.  It was just a spur-of-the-moment thing, as I hadn't planned on adding an antenna mount to this vehicle.  The black part at the bottom of the mount is a chunk of soft plastic I had in my junk box (the kind of plastic Green Army Men are made of).  Instead of a spring, it adds enough antenna flexibility to prevent anything from becoming accidentally broken.

 

The Crew:

Here's the crew.  Originally, I looked high and low for a Hasbro German Tank Commander figure, but couldn't find one at a reasonable price.  It seems that figure must've been made of gold or something.  Instead, I found a great deal on a Dragon tank commander.  This is the "small body" version that's noticeably shorter than the other Herculean Dragon figures.  He came with a great uniform and all of the appropriate accessories (headphones, throat mic, etc).  I also picked up a Dragon figure to be the gunner.  I forget what figure this is, but he came with some great coveralls in addition to his black tanker uniform.  The black tanker coveralls were used to "kitbash" a loader along with some Cots-type boots and a set of headphones from the junkbox.  The loader figure was "Christian" the snow troop skiier guy, so he already had gloved hands (appropriate for a loader!).  As for the driver, I used a Cotswold figure.  He seemed to be able to get in and out of the driver's hatch more easily than most figures.  I ran out of German uniform options at this point, so I grabbed some black clothing ('Nam Viet Cong, I think... SWAT perhaps) and gave him a German pistol and junkbox headphones and he makes a passable driver.  The Loader and Driver both have those clear rubber bands holding on their headsets.  Those softer plastic headsets don't stay on worth beans.  You have to make do with what you've got , though!  If I ever run into a good deal on black tanker uniforms and better headsets for the Loader and Driver, I'll swap stuff out so they all look as good as the Commander and Gunner.  Until then, these guys will have to do!

  

Afterthoughts:

I still could do some work on it.  The interior could use some Schmeisser racks, a desk-like feature for maps or target grids (or at least a peg to hang a clipboard on), a radio set to give the antenna some sort of use, and probably some cup holders (for their wives and/or girlfriends).   I could add some equipment to the hull also; items such as shovels, picks, backpacks, helmets, crates, netting, etc, could always come in handy for a front-line anti-tank gun crew.

Glue was a real problem during this project.  I'd build something only to find it was a crummy bond a few days later.  It's a bummer to do a lot of head scratching and lining stuff up to glue... then add more layers of work on top of that... only to find the lowest level of glue pops apart under the slightest pressure!  GRR!!!  I tried Super-Glue, Gorilla Glue, 2-part Epoxy, model airplane glue, and JB Weld.  Of these, I found model the Gorilla Glue worthless for bonding this thick styrene.  Model airplane glue was also worthless.  Epoxy was a semi-useful bonding agent, but after a week or so it would be weak.  JB Weld was great!  It held everything - even dissimilar plastics - and when it dried I could shape it with my Dremel tool just like plastic.  I love that stuff!  I'm now a JB Weld fan.

I also added a field telephone that I added as a vehicle intercom, but I forgot to get pics.  The "intercom" was actually a modern Hasbro chemical detector box that I cut the face off and added a scratchbuilt handset.  It lives in a hinged panel on the left ("passenger side") rear of the vehicle.  The idea was that infantry could grab the intercom to communicate with the crew in a high-noise environment (like combat).  There's also a plug for the commander to plug in an extension cord so he can stand on a nearby hillock or reinforcement with binoculars to recon the way ahead and still communicate to the crew over the intercom.  It could also be useful for the commander to correct indirect-fire.  Those might be groovy pics.  If I ever get around to it, I'll get some pics of the intercom and add 'em to this site.  I doubt I'll get around to it in view of all the other projects in the hopper, but y'never know.  

 

Hopes for the future: 

It'd be great if 21^st Century would put out more of these affordable R/C vehicles.  Vehicles like the Carro-Armato M.14/41 at left or the Semoventa at right would rock!

 

 

 

 

 

 

 

 

 

 

A desert-prowling Sahariano (Saharina?) would be a cool one... they could use the HummVee R/c guts for this one!

 

 

A PzKw 38t (right) would be my hands-down #1 choice, though… it's small, like the M5 Stuart, and could use the same "innards", thus should be easy to manufacture.  It's sized right for combat with the M5 Stuart and the chassis could be used for a host of other weapon platforms, too!

 

Dreaming is free...

 

 

I hope you enjoyed looking over my little project.  Now it's ready to patrol the back yard and do battle with allied Joe forces for control of the backyard.  Today the German SPAT 75mm will seize control of the patio, then they will move toward domination of the whole backyard… and tomorrow -- THE WORLD! 

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NOTE:  if you wish to contact me regarding anything on this site, the Sandbox newsgroup is the best way (alt.toys.gijoe). 
When I had a functioning email link on my pages, Spambots practically demolished the usefulness of my email account.