Class 37 roof detail diffrences

[vac_basher]

Could somebody kindly explain why the two Tractors in the photo below have diffrent roof details? (for the record they are Bachmann's versions of 37035 and 37239)

Is that the boiler exhaust that's plated over on the top one? What's the little thing to the right of it?

Also, why dose one have a rivited roof section and the other a smooth one? Is there a list available anywhere of whice one's had/hadn't the rivited roof?

And finally what is the thing in proximity to the horns that I've circled on the right. Could it be the radio antenna possibly?

Once again, thanks in advance:)

[giz]

_{The one at the top has no boiler, the one below has. The large hole is the boiler port, the smaller fittings are the boiler safety valves and the thing on the cab roof is a vent.}

 

_{The difference in rivitted to flush roof panel occured around the middle of the production run but I don't think it coincided with the change from split headcode to central. There is bound to be someone along soon who knows exactly when.}

[vac_basher]

Thank you Giz. That was most helpful.

 

What I actually was thinking of doing with these models was exchaning the noses and horns, so I'd have a Dutch one with center headcodes, and then I wanted to use the Railfright Coal body with the split headcodes as a basis for 37350. But it doesn't seem this is going to be possible.

Looks like I'm just going to have to wait till Bachmann bring out something more suitable....

['CHARD]

You've not accounted for the cantrail grille differences either, which apply to early and RSH locos rather than VF-built examples (from memory).

 

So-called headboard- or Central Wales clips above the headcode panels on centre-headcode locos also vary (not that this would apply to 37350 of course).

[37114]

D6700 - D6798 had rivetted roof, thereafter plain rooves. Cantrail grilles with extra dividing bars were fitted to all RSH 37's (D6769-D6795 D6877-D6898) and D6700 - D6705 but with a groove round as they were removeable. Horns on roofs for all centre boxes including D6773/4/91 converted after accident damage repairs.

[D6975]

Cantrail grilles with extra dividing bars were fitted to all RSH 37's (D6769-D6795 D6877-D6898) and D6700 - D6705 but with a groove round as they were removeable. Horns on roofs for all centre boxes including D6773/4/91 converted after accident damage repairs.

 

Close - D6700-4 had the extra dividing bars and a strip below the cantrail grilles with the dividers extending down the bodyside to this strip.

D6705 was unique in that although it was VF built, the cantrail grilles were identical to RSH built locos and not removable. It was almost indistinguishable from a RSH 37.