Construction

Removal of the grills and transmission service hatch

Final drive housing

Gun assembly

Transmission hatch combined from SG PE set and scratch built grill

Cut grille test fit before bending the hatch

Since there is no vertical step between the engine and transmission hatch, as with original, I had to build one

engine louvres fitted, transmission hatch assembled and hinges added to the latter

Clearer view of the hinges of the transmission hatch

Resin road wheels with pattern in the rubber bandage with 42 holes, 10 bolts
OKB S72011

Both are from "OKB" resin sets:
TOP:
S72082, sprocket used for T-34 etc. from 1942
BOTTOM:
S72011, road whels as described in previous photo

kit road wheels with 42 holes and NO pattern in the rubber bandage

Assembly so far w/o the gun.
I held up on the each side to slowly fill and dry tiny sink holes in the sides of the exhaust housings with thin glue

front with internal gun rig test fitted and lamp hollowed

side view with auxilliary fuel barrels fitted and the fuel caps replaced with 2x parts made with punch & die sets.
The cap is hexagonal and the bottom part is round (a wee bit thick, too but I call that artistic license 😉

chassis with "home made" blank cover to hide the missing engine

rear of the SU-122 with the replaced handles of the aux. fuel tanks properly visible.
I left the simplified handle of the round inspection hatch since it would have destroyed a lot of detail

the "invisible" interior

the interior bit of the gun mount in detail
It's ingenious in allowing you to snap fit it and move the gun if you like. The actual gun is pushed through the 2x latches at the bottom and fixed with a bolt

Test fit of the gun and shield.
The white blob on the shield was just a shallow depression in the kit part so I sanded it flush and created a one according to reference photos

gun, shield and the bolt to fix it in place

the replacement gun barrel I messed up a little by using to much glue but the factory welds weren't always pretty either. Let's wait how "bad" it looks with the primer/base coat on

transmission hatch again as a detail photo

Test fit, looks ok

This is how it looks with the blank in place

Test fit of the "blank"

This is how it looks against the light w/o the blank

Bottom of the hull with all wheels glued in place

Side view of the hull & wheels

resin vs plastic
bandage patttern vs no pattern
The idler is quite OK for early 1943 built SU-122s but I could have used "reinforced" ones but kept the kit ones for simplicity of assembly

In contrast the delicately detailed sprocket was a bit "soft" in the kit byt fiddly to fix in place.
I should have filled the hole and created a mounting axle both was too lazy. So fiddly it had to be 🙂