Arctos IVA Heavy Tank

Arctos IVA3 Heavy Tank
Designed for use with minis in the "heroic" or 28mm scale as a heavy tank.

Updated 3/23/25 - check the bottom section for condensed list of changes and additions

"A variation of a common type of heavy battle tank, the Arctos IV is the forth in it's particular design lineage and comes in a "regular" variant (6 crew) and "assault" variant (8 crew) with additional sponson-mounted weapons. With the ability to mount a variety of different weapons in it's hull and turret, it serves as a stalwart and versatile armored support option in many armies across it's home sector."

Meant for casual war-gamers out there who just need a tank quick and cheap. All parts are meant to be printable in FDM, but sponson weapons in particular would benefit from being printed in resin. 
Sponsons are designed to push-fit onto the ribs on the sides and hang tightly, so that glue would not be required and that they can be taken on or off as desired. Care should be taken when inserting weapons into them or the turret, as a decent amount of force may be needed when first inserting them (this is more for your safety, not the parts). Sponson Weapons are best inserted or removed at a 45 degree angle. Turret weapons should be printed on their sides for best part strength, and are best inserted or removed at 0 degrees elevation.

Main Weapon choices:

• 155mm low velocity gun with coaxial GPMG  
• 125mm high velocity gun with coaxial HMG  
• 140mm hyper-velocity gun with coaxial GPMG
• 105mm Light-weight HV Guns, one with coaxial Dual micro-rocket guns and one with a coax HMG
• Twin 40mm Autocannons with coaxial GPMG  
• 35mm Rotary Cannon   
• 160mm Howitzer  
• 175mm Rocket-Mortar 
• 240mm Spigot Mortar with Petard Charge  
• Twin Heavy Laser Weapons 

A note on the spigot mortar; the petard is made as a separate piece, so you can choose whether to use it or not. Be aware though, it fits snugly, so once it's in the Mortar, it's probably not coming out.

Hull Weapon choices:

• Automatic rocket gun
• Heavy Flamethrower
• Heavy Laser weapon

Sponson Weapon choices:

• Automatic rocket guns
• Heavy Flamethrowers
• Heavy Fusion Torches
• Plasma Launchers

There is also a “Bit Adapter” option, allowing for the use of certain bits from other model kits you may have in the sponsons by inserting them into the adapter.

Included are a number of turret addons which are meant to slide onto the mount-protrusions on the turret:

• External stowage boxes, one with a side opening lid and one top opening lid
• Rear turret bustle with three stowage compartments
• A box-style spotlight, with both a right and left side version.
• External "tuning fork" antennae module
• Smoke launchers
• Pintle mounted HMG; these go onto the post sitting between the Commander and Loader's cupolas.

The Turret and Spotlights feature rails that can accept either a 70mm or 105mm single-use ATGM.

In case you want to make something yourself for the turret, mounting points are .050" wide, .060" deep and spaced about .400" apart, with the exception of the front mounts where the geometry of the turret front makes it so you can only use ~.040" of the mount depth, and the back center mounts, which are .265" apart.
(yes, imperial units, gross, I know)
Feedback and makes are welcome.

Example printed using Overture Matte PLA on a Mk4, Mk4S and Mini; larger parts (Hull, Turret, Sponsons) were printed at .2mm layerheight, smaller parts printed at .1mm layerheight. All parts printed with .4mm nozzle. Resin examples of parts shown were printed on Mars 2 Pro.

--Changes and Additions--
*Unless otherwise stated, all new parts are compatible with old parts.*

A3 Update (March '25)
Turret model has been changed to resize hatches and add an ATGM mounting rail directly onto the turret.
New Turret weapon options added:
-Twin Autocannons
-Rotary Cannon
-Howitzer
-Rocket-Mortar
-Spigot Mortar
-Twin Laser weapons
-140mm HV gun
-105mm LW-HV Guns
New / changed Turret items:
-Smoke Launchers for both the left and right side of the turret
-Spotlight has been resized, turret-side geometry changed, given a left-side counterpart, and given a mounting rail on top
-A Rail has been added to the spotlight for mounting single-use ATGMs, and the geometry of the spotlight's mounting side has been changed
-Pintle mount and HMG for the turret
-70mm Single-Use ATGM
-105mm Single-Use ATGM
Sponson weapon models have been altered slightly.
Hull-mounted Heavy Laser Weapon has been changed.
A new version of the Hull-mounted flamethrower has been made.
Added optional external fuel tanks.
Changes to description. Added the tiniest bit of fluff.
Organization added / changed to model files.