I just got 6 Intermountain boxcars with metal roofwalks, all 6 came with a bow in the roofwalk, would return them to vendor but they do not have more. Was going to e-mail intermountain for their advice but their email link did not work for me and they did not have the email just listed so I could enter it myself. I have skills so I proubly just need advise from those that have fixed this problem before.
I've had good luck with flexible CA like Poly Zap or MicroBond. Use something like a scrap of wire to apply a small amount to the car, and hit with some CA accelerator to set the joint quickly.
Rob Spangler
when you say metal, I assume you are meaning a plastic casting that looks like metal as opposed to somehtng that is etched metal.
I can think of a couple of options:
Soak then in hot water for a few minutes to soften the plastic, then lay down on a flat surface with a weight on top until they are cool. If it does not fix it the first time, try again with hotter water.
Do a similar thing, but heat up with a hair dryer.
IN both cases, you want to heat the parts up enough to soften them, but not melt the plastic
George In Midcoast Maine, 'bout halfway up the Rockland branch
They ARE metal, not plastic. This is a common problem when two dissimilar materials are fastened in this manner. The plastic expands and contracts more than the stainless steel.
They were glued together in a specific room temperature environment, which I would think to be rather warm. When the temperature fluctuates on either side of the temperature they were assembled, this will happen.
To prove this, put the boxcar in the freezer - the plastic will shrink more than the steel and the bow will be even worse. Warm the car with a hair dryer and the car will expand more than the steel and pull the walkway down flat. If the walkways were glued on in a cold temperature, this bowing would never be a problem.
You can sometimes fool the plastic shell into a new memory by repeatedly putting it the freezer, then warming it with a hairdryer until it memorizes a mid-point that pulls the walkway down tight. It does work - I've done it a number of times. Just don't get worried when you take it out of the freezer and it's bowed even worse than it started, it will pull back down with heat.
This time of year is usually when these problems start to crop up as the days get cooler. Keep your train room around 80 degrees and this probably won't be a problem !
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
I just got them, delivered that way. It is around 65 in the house now, haven't turned on the heat yet.
If the walkways attach by small stubs that go through the roof, you can slightly elongate the holes in the roof on each end of the car, then only apply glue to the center stubs. This leaves the walkway/car roof to move independantly of each other.
South Penn
Mark R mentions the problem w/ dissimilar materials and temperature. This is a common problem w/ these. many in my club have them. Some have actually broken loose. One fix is to gently pry up and try to break the bond. If the roofwalks will easily be completly removed, allow plastic shell/ model to aclimate and warm the metal prior to reattaching w/ CA. The roofwalk should be under a bit of tension as they coll and aclimate to the entire model.
Modeling B&O- Chessie Bob K. www.ssmrc.org
The one came loose from the end with no problem. Friend say he fixed the problem (metal grills on plastic from an F unit) by using white glue and weighing it down once loose from the bowing end. Tried this on something else and it worked but this was not a roofwalk reattach so I guess we will see.
Taking the expansion / contraction aspect into consideration, I will put the car in the fridge for a few minutes (not the walkway) prior to gluing on the walkway and have yet to ever have one bow on me. Same goes for attaching grills on F-units.
As the shell warms up, it will put the walkway under tension as opposed to compression. The only way (in theory) it could ever bow again is if your train room gets colder than your fridge !
Read the begining, these are RTR.