I have a 226E that has a tweek on the cab roof. Does anyone have any experience straigtening metal pieces of trains without doing more damage - ie having the piece break off or burning off the paint.
Any insight would be appreciated!
It depends on how sound the rest of the casting is and how bad the bend is. Some guys use a soft mallet with a curved piece of hard wood for backing and some have luck using a propane torch to warm (but not melt) the corner. The problem is the casting is old and somewhat brittle and the bend that you want to fix has “work hardened” the material in the bend which makes it suceptable to fracture the next time it is bent( which is likely to be you trying to fix the original bend) The heat can sometimes help, but of course zinc has a low melting temp (I’ve melted parts just over a gas stove burner by holding them too close for too long…and in that case it was only a few seconds.
So be careful and good luck!
Sooo, it can be done, but many times its a little bit delicate. Hamfistedness will likely cause much more damage to the part.
You might be better off to leave it alone. I, too, have (had) a 226 with a bent roof. I tried all the tricks everyone else has mentioned time and time again. When I got to the part where heat is applied, I tried a heat gun first–no help. In desperation I resigned myself to repainting, so I used a butane torch on it. Instead of it melting as others have described, I noticed little beads of metal (like solder drops) “sweating” out of it. At that point I figured that was about all the heat it would take before a catastrophic meltdown-- still it never became malleable enough to move.
My next move was to use a padded vise with a cab-contoured wooden mandrel inside the cab. I applied firm pressure and let it sit in the vise for several days–again, nothing. By now I thought I had nothing to lose, so I padded some vise grips and tried to bend just the corner up–snap! It finally had enough and broke. I attached it the best I could with some JB weld, smoothed and repainted the area. It isn’t bent anymore, but I lost all the cast-in roof detail.
As others have mentioned, some success is possible sometimes using these methods with postwar locos, but the prewars seem a different animal. I think there might be a difference between prewar and postwar metal.
For some strange reason, I’ve seen more 226s with bent roofs than not; 225s and 224s–more straight than bent…go figure!
almaexpress,
[#welcome] I’d suggest leaving the cab roof alone. Given the rarity of the 226E, I wouldn’t try straightening the bend. It might bend back, or it might snap. In my experience, the metal usually snaps. If I was in your shoes, I’d just leave it alone and be glad that I have a 226E. Besides, things like bent cab roofs add character.[:)]
Don’t mess with it. I just went thru the same thing with a 646 that took a dive off my layout. Tryed to fix a little bend in the cab and the 3rd hit POW off came the corner. If it’s not that bad I would leave it alone and shop around for another shell.
There is only a narrow temperature range in which zinc is malleable. This from Wikipedia:
The metal is hard and brittle at most temperatures but becomes malleable between 100 and 150 °C [212 and 302 °F]. Above 210 °C [410 °F], the metal becomes brittle again and can be pulverized by beating.
welcome! and I have to agree, if it’s not tht bad, let it be. I straightened the cab corner of my 2046 after a dive, but I was sweating bulets the whole time. As rare as a 226E is…let it be.Or find another shell and sell me the bent one 
Bob,
I also looked that up, and used a pyrometer to monitor the temp while I was doing my heat experiments. In that temperature range, it wasn’t any more malleable than at room temp. I don’t think their castings were pure zinc-- whatever alloy it may be it sure has some strange properties.