The simple answer to your question is everything on the chassis was painted black except for the engine and gearbox (and occasionally the gearbox was black!).
The more complicated answer:
Chassis and all components (defined as all parts put on the chassis except for the body parts, engine, and gearbox) were generally delivered to the production line painted black. Other than the chassis, it’s likely most components were delivered to MG pre-painted by vendors. No primer was used, nor was there any paint prep done to the components.
On the chassis track (track is what MG called the sections of the production lines), the next to last station was a paint booth built across the track. The chassis was rolled into the booth and overspray guards were placed on the back of each wheel to keep any overspray off the wire wheels. Then the worker (Sam Peach did this job for most of TC production) did touch up spraying of the assembled chassis in a ‘quick and dirty’ fashion, painting black everything that wasn’t black already. Hardware, brake lines, exhaust, grease - everything was painted.
The thoroughness and neatness of painting varied during production.
The sheen of the paint varied. Photos indicate that most was a semi-gloss level (think matte, eggshell, semi-gloss, gloss on a scale). Most of the photos show the touch up paint applied at the paint booth was a higher gloss than the paint used before assembly.
Since there was no detailed paint prep and paint was single coat, much of the black paint likely disappeared an any TC that was well used during its first ten years of use.
Y types and TDs had the same chassis paint process.
I’m sure there are variables on what left the production line and others may have examples to prove the exception to the rule.
Hope this helps on your early chassis assembly process.
TC0273, TC0279, TC2040, and a studio full of 11 MMMs
This exactly what I was looking for! It confirmed my feelings. I have done two TD's in a similar fashion but when I started on the TC I saw so many different variations that I began to wonder what was correct. Thanks a lot.
But also know that few judges will note natural brake fittings or lines, not having the sump painted, or displaying a level of finish far better than the factory would provide. To my way of thinking, both slavish attention to and ignorance of originality can be carried way too far.
I've seen cars where the chassis was painted red, where the brake lines were painted green, and where all brass fittings, the sump and bell housing were mirror-polished. I've seen cars where every imperfection of the entire chassis was sanded and filled so that it was smooth as glass, and I've seen chassis where absolutely no prep was carried out, and the surface looked rough and irregular. I've seen mirror-gloss paint, and flat-black on the chassis.
There is a middle-ground, which is what I aim for. I don't paint or polish my sumps because I suspect it limits the cooling. I don't polish my brass because it removes the crispness of originality. I use semi-gloss black on almost everything that was originally painted black, because I think it looks good, and overall more original.
I like originality and I think all three of us think the same. I show my cars and I want others to see them as they left the factory with as few personal embellishments as possible. Gloss black looks bad. I just returned from SEMA and aside from customized cars, all chassis were semi-gloss or matte finish in color. My cars (Morgans and MG's) are judged at AACA events and usually are awarded Senior Grand National status. I've seen cars given the same awards and they are not "original" but they appeal to what appears to be correct in the judge's minds. Oh well, to each his own. Mine will be as close to what it was when it left the factory as I can make it. Just my preference. Thanks for your input.