M4A3(105) Sherman barrel can be depressed into its own hull

[Colin Basnett]

No description provided.

[Matt Hands]

Defprop to change is CustomPitchDownLimit in DH_ShermanCannon_M4A3105. Other pitch variables have no effect on cannon pitch.

Current = 63716 = 10 degrees depression To prevent clipping hull = 64800 = 4 degrees To prevent clipping middle periscopes = 65150 = 2.1 degrees To prevent clipping driver's hatch periscopes = 65300 = 1.3 degrees To prevent clipping guards over hatch scopes = not possible, barrel would have to be slightly elevated !

Of these I would go with 65150 as the best compromise, looking fine in most situations and still allowing the cannon to be used effectively.

But it looks to me like the problem is in the turret model and/or how the pitch bone is placed. The mantlet and barrel are almost sitting on the hull and it doesn't match photos.

[Colin Basnett]

Yea, it looks more like the turret is placed too far back in the hull. Perhaps the bone position just needs some TLC.

[Matt Hands]

All versions of the Sherman hull have the turret attachment bone a few units below the top of the hull. This is made worse because most of the turret versions have geometry below the mesh origin. So the turret sinks into the hull. As the turret turns, it clips through parts of the hull mesh, towards the rear. This is particularly bad on the 75mm. The lowering of the turret also brings the barrel closer to the hull, so affecting pitch down limits

Looks like the modeller has tried to adjust for this by setting the turret's root bone (TurretAttachment1 usually) a few units below the turret origin in most of the models, perhaps thinking that bone would attach to the hull bone, so lifting the turret relatively. But it doesn't have any effect as it's the turret origin that gets located on the hull's attachment bone, not the turret's root bone.

To me, the 105mm turret has the barrel significantly too low on the mantlet. In photos the barrel looks centred vertically on the mantlet, where in the model it is noticeably below centre. Also, I think the modeller has flattened the lower front of the turret from the 75mm base mesh, perhaps by mistake or perhaps to avoid the mantlet clipping the turret when pitched down. But I believe the 105mm was 'plugged in' to the standard 75mm turret, without re-shaping it. If the lower mantlet does clip, it's easy to re-shape that.

[Matt Hands]

Forgot to mention that several Sherman turret models are also off centre in the Y axis, so rotation is 'wonky', as we would say over here. Centre of mesh, root bone and yaw bone should all be zeroed on Y axis (plus pitch bone and muzzle/barrel bone if cannon is mounted centrally).

[Colin Basnett]

Not critical for the release of 6.0.

[Matt Hands]

Fixed in commit a4c17fd.

Corrected turret to raise up out of the hull, adjusted model so symmetrical and centred, barrel no longer clips into hull. Skeleton still of centre, just working around it, plus the gun barrel sits too low on the mantlet, so the mesh & rig could do with another re-work in future. Not doing that now though, as any adjustments to rig or to barrel position would require all anims to be re-made. Adjusted interior mesh and collision static mesh to match.