Perhaps these pictures will clarify how I straightened a warped roof on my MDC baggage car...
For your diner, perhaps an interior partition or even drawn window shades might lessen the visual impact of a giant screw in the aisleway.
dknelsonAlthough I have not used it on passenger car roofs, I have "bulled" somewhat warped plastic structure kit sides into being flat by cementing a stiffener which is held in place with plenty of clamps while the cement sets. I think this a variation on what Dr. Wayne recommends above.
Dave's reply, above, offers another option for the warped roof: using solvent-type cement, place a strip of Evergreen .125"x.125" strip material to the underside of the roof, positioning it so that one side is at the approximate mid-point (side-to-side) of the roof. It should extend the full length of the straight portion of the roof. Cut a piece of .060" sheet styrene to the same length as that strip, and as deep as you can make it, without it being easily seen through the car's windows.
After clamping the warped roof (upside down, of course) to something straight, cement the stiffener to the side of the previously added gluing strip and to the roof - clamp it to the gluing strip if necessary. Allow the joint to fully harden - overnight, if necessary, before removing the clamps holding it in place. It should come out straight and fit perfectly onto the body.
Wayne
Heartland Division CB&QHot water can work .
I can imagine how a heat gun would end for me. I found undercarriage detail, but not bottom most piece of plastic. As there is not much detail, I should be able to make it out of styrene without difficulty.
Henry
COB Potomac & Northern
Shenandoah Valley
Hot water can work .
Place the plastic roof in a pan of very hot water and wait for the roof to become bendable. Then work with your hands to get it back in shape. Hold it to correct shape as you can let it return to room toerature.
GARRY
HEARTLAND DIVISION, CB&Q RR
EVERYWHERE LOST; WE HUSTLE OUR CABOOSE FOR YOU
I've actually had good luck with a hair dryer set on high and a little bit of preasure in the appropriate direction on parts like that. You still have to be careful not to overheat the part, but it will be more controllable than a heat gun.
mbinsewi If you use the heat gun method, be CAREFULL! I've destroyed a couple of cars doing that. Everything seems like it's going good, and then in an instant, the whole thing melts and deforms beyond use. Mike.
If you use the heat gun method, be CAREFULL! I've destroyed a couple of cars doing that. Everything seems like it's going good, and then in an instant, the whole thing melts and deforms beyond use.
Mike.
Yes there is a "magic moment" with heat guns and styrene, as those of us who use heat to create bulges in gondola sides (between the verticals) have learned. I always have a spritzer of cold water, or even a tub of cold water, nearby to stop the melt if I go too far, hopefully before permanent damage is done.
That is why some guys have used immersion in very hot water which is warm enough to somewhat soften plastic but which would turn to steam before it is hot enough to actually melt/deform the plastic. Perhaps rubber banding the warped piece to something perfectly straight/flat (or even bent slightly the contrary direction) with a lengthy immersion in very hot water would work. You would not have the heat source involved during this, so hot water but NOT on the stove top.
Other have used heat lamps or even just ordinary incandescent light bulbs ("what's an incandescent light bulb, grandpa?") but anyone who has seen plastic models melt under photographer's lights knows that they too have their magic moment where the heat goes too far.
Although I have not used it on passenger car roofs, I have "bulled" somewhat warped plastic structure kit sides into being flat by cementing a stiffener which is held in place with plenty of clamps while the cement sets. I think this a variation on what Dr. Wayne recommends above.
In some extreme cases I have "broken" a warp by sawing the offening piece in two and then cementing it back together, again with a stiffener piece of some sort, and again well clamped during cementing. This usually calls for some surgical filing/putty work at the site of the cut afterwards.
In the case of slightly warped wood one can try to break the warp with incisions into the back of the piece that makes it bendable at the location of the warp. The problem in trying this with styrene is styrene's tendency to snap where it is scored (score and snap is one of the great virtues of course in using styrene, but a negative or at least a risk in this particular situation).
Dave Nelson
Once you find all the parts, maybe you can detail the car the way you want, then glue the roof on, with the rubber band.
Maybe you can carefully cut the roof at a seam, and set it as two sections. It would be tuff to hide that, but maybe?
My You Tube
The form was very slow for me last night. Thanks for the suggestions. The undercarriage seems to be missing from the kit. Looks like I have some boxes to look through.
Well, make that a triplicate post.
Is anybody else having difficulties with their replies not being accepted in a timely manner? Mine seem to have taken about 20 minutes, after my initial click to post, followed by at least two more clicks when nothing seemed to be happening.
Duplicate post.
I've removed the warp from the roof of a baggage car by cementing a built-up block of .060" sheet styrene to the underside of the roof, about mid-car, then running a long screw up through the floor of the car, and into the block.
While the block wouldn't have been noticeable if the car had had windows, like a coach or diner, it might be difficult to hide or disguise the long screw in your particular car.
I have 1.5mm gap at the center of the roof, when the ends of the roof are touching. I don't want to glue the roof, which would work with some rubber bands, because I want to be able to add figures, lighting etc at some future date.
Is there a way to de-warp the roof?