IIRC the Germans sold a load of M47s to Italy when they were retired from the BW, so they would have arrived with rain gutters.

The circular plugged holes are interesting, as they look to line up with the trunions for the main gun. But it seems odd they would need access for assembly, deliberately weakening the cast shell and then having to plug it up. Do they appear in original period photos? I could see them being a response to a repair or upgrade issue...

Nice pic. I think I may have solved the issue of why those plugs are there. In the manufacturing process the trunnion holes would b roughly cast into place, but would need to be machined from the outside before they could be fitted with bearing. Then to maintain structural integrity the plugs were welded in.

As I recall there were five foundries that cast M47 turrets. They all had the same part number, 7537163, so they were all the same design. The variations in the casting at the turret ring correspond with the molding practices at the particular foundry. (This is evident in Sherman turrets as well.) General Steel Castings, for example, used a re-entrant mold that gave a smooth undercut to the underside. Scullin Steel was similar but with smoother contours at the front. Continental Foundry and Machine's Wheeling plant was one of those who more or less cast the turret straight down from the widest point and machined a cylindrical clearance undercut at the base and a rough, conical clearance above that. The position and style of the foundry markings also corresponds to the foundry.

The hand and combat pack rails were a time-of-production change, as far as can be told. The rain gutters are believed to be a feature of tanks overhauled by or in Italy.

KL

...and sometimes the manufacture's mark was different, or never shown at all.

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...and sometimes the manufacture's mark was different, or never shown at all.

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On the real tanks or on your models? Marks are always present on the real tanks. They may be partially removed to mount a tool holder or something, but they are there.

KL

Of the M-47 kits, which one OOB is the most accurate? Someone said the Italeri (or I guess Tamiya now) was the most accurate of the kits out there. I honestly don't know. I have no M-47s in my stash and it is on the to get list. Sorry, not trying to hijack the thread.

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Nice pic. I think I may have solved the issue of why those plugs are there. In the manufacturing process the trunnion holes would b roughly cast into place, but would need to be machined from the outside before they could be fitted with bearing. Then to maintain structural integrity the plugs were welded in.

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They wouldn't be cast in place, that would be too difficult given the size and shape of the main shell and the need to accurately machine them in alignment. The turret was cast solid (probably) and the trunnion position was bored through the side once the centerline of the turret race was established. (It was normal US practice to use the race bearing seat diameter and seating face as the datums for dimensions on turrets.) Bars were installed to form the trunnions and cast caps or plugs (cast numbers are visible on some) were welded in place on the outside.

KL

Can you imagine a datum line being mathed in to production with only a circular slide rule and calipers! That in itself was the standard until computers showed up.

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Can you imagine a datum line being mathed in to production with only a circular slide rule and calipers! That in itself was the standard until computers showed up.

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They didn't have to do that on the production floor. The drafters had already resolved things into X and Y components when they located things on drawings.

To place the critical features a machinist (or set-up man, as some shops had) would place the casting approximately level and on center and the casting would be nudged around, using an indicator on some key features to get the best, equalized, fit. It would be clamped down and the race seat would be machined. From then on the datum was set and it was a matter of moving the machine's spindle so-and-so from the center and such-and-such up from the base line. (For example, on the M4A3E2 the trunnion axis was 37.000 +/- .005 from the center and 14.687 +/- .010 from the base line. On the M60 the dimensions were 38.50 +/- .01 and 13.50 +/- .01 .)

KL

Hello fellas. A detail that I have found simple to add is the drain openings located on each side of the hull, just below the turret ring. I have not seen either of the Takom kits up close, perhaps they are a feature of these newer kits.

If you are able to get down to Fort Bliss, Texas, there is/was one that is accessible with open hatches.

Respectfully,

Allen

If 18Bravo takes this thread to include the hull, I'm sure those holes will be featured at some point. I think they are bilge pump outlets (if memory serves me right).

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If 18Bravo takes this thread to include the hull, I'm sure those holes will be featured at some point. I think they are bilge pump outlets (if memory serves me right).

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A thread goes where it goes. I've been known to steer one off course a time or two. As long as it doesn't become a pissing contest, who cares?

I may not have quite as many photos as John, but when I do a walkaround, I try not ti miss too much.