Twist, Turn and/or Bend!!

I tried bend and twist and so far no problems. Some folks state that they uses a soldering iron to heat the tab before they bend it straight to take it apart and had good luck.
What I am in the process of restoring a standard gauge 8 loco shell that I picked up on eBay. There is a large brass insets on each side of the shell for windows/grill/name boards that are held in place with tabs. Once I had the shell apart and stripped of paint I noticed that the shell is not soldered together, What I did was to heat each tab wit a small torch until it was red hot then to let it cool down very slowly (do not quench) to anneal the steel (make it softer) I did this twice (hope it works).
I just finished painting the shell and in the process or finishing the two brass plates with clear and a color for the windows. Unfortunately I will be going to Vegas for over a week for a trade show (no-Fun, just work). When I get back the paint should be dried and I will post the assembly results.

looks great Popi! I usually will twist a tab when I put a car back together, but I will leave some of the tabs straight in case the car needs to come apart again.

Like Dave, I usually twist the tabs when reassembling and only use just enough tabs to hold it together. That way if one should break at some point during a future disassembly I have some spares. 

On some of those cars with attachment tabs I've found ways to use a long machine screw through one drilled hole in the center of the floor/frame, and thread it into existing or added material inside the car. I leave the tabs straight just for alignment purposes. The screw attachment allows easy dis-assembly and reassembly.

A prewar Lionel 814 boxcar has a cross-piece just under the roof center which can be drilled and threaded for a machine screw coming up through the floor. It doesn't affect the external appearance of the car. I opened the car to straighten a bent floor which made the car wobbly on its trucks, also upgraded the couplers.

I'm also of the twist mindset when reassembling, also only use a couple of tabs. These were meant for kids, but in the hands of a caring adult, not as many tabs need to be used.

Steve

Also, if you are privy to the finer points of tabs and reconstruction of tinplate trains,

it will help in buying pieces at train shows that dealers say are "all original" or "pristine".

All one has to do is inspect the under side of any tinplate rolling stock. If you find scratches

and/or scrapes near the tabs, that is a clue that the car has been tampered with and either

taken apart and/or reassymbled from parts from other cars.

Popi posted:

.... If you find scratches and/or scrapes near the tabs, that is a clue that the car has been tampered with and either taken apart and/or reassymbled from parts from other cars.

have to say there there is nothing wrong with disassembling a tinplate car to clean it.  i do this with almost all enclosed cars (boxcars, reefers, passenger cars, etc).  can't say i've ever left a scratch when prying a tab as i only use my fingernails.  if there is a chance i'll need to take the body off again, i'll give a very slight twist to two tabs, but most of the time when i know the car is as clean inside as i can get it, i'll usually restore all the tabs.  Marx tabs are probably the most robust.  though i've never done a test to see just how much rebending they can withstand, i'm certain it's more than 2.  the most problematic cars i've ever dealt with are early Flyer cars.

i differentiate twist vs bend depending on the geometry of the body where the tab attaches.  in solid side cars, where the body is very rigid, the bend will hold best on opposing sides, but if the tab comes off a strut as in a tank car, the twist will hold more solidly.

cheers...gary