Warped Roof Questions!

Discussion in 'Scratchin' & Bashin'' started by Lighthorseman, May 14, 2004.

  1. Lighthorseman

    Lighthorseman Active Member

    Up to this point, I've not worried too much about this, but when I start scratchbuilding structures in earnest, I'll want at least a few rooflines that are actually straight. The two structures that I've built in O scale both have a warped roof.

    Have a look at the little wooden logging...er...fishing shack. The local LPPs have done a lovely job of re-shingling it, but it never occurred to them to straighten the roof up.

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  2. Lighthorseman

    Lighthorseman Active Member


    ...Then there's the local bakery. This used to be the general store, until they built a larger structure.

    The fishing shack has individually cut wooden shingles glued to matboard.

    The bakery has strips of painted 3 by 5 inch index cards glued to styrene.

    Both were placed under a big pile of hardcover books in an attempt to straighten them out, but all recovered their warp again after a short time.

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  3. Matthyro

    Matthyro Will always be re-membered

    Looks like you need to put a few rafters with a cross beam to prevent the sway. I must admit I like the look but you are right if you build a modern building you will want straight lines.
  4. jkristia

    jkristia Member

    I think you would have to add some 1/4x1/4 wood strips for bracing on each side of the roof, then add the shingles (on the other side of course), then put them under your pile of heavy books until dry. At least that's what I would do, not sure if it's the best way or not.

  5. Lighthorseman

    Lighthorseman Active Member

    Even In HO...

    I had the same problem, but with a bit of a twist, interestingly enough.

    Here is an unfinished feed mill, based on a Ben King article in Model Railroader - my first scratchbuilding attempt ever. :rolleyes: Someday, I'd like to actually finish this off, and put it in a diorama or something.

    This building hasn't the roofline warp of the other two, but the roof ends did culrycue inward, and once again, no amount of pressing under weights seemed to eliminate the warping problem.

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  6. Lighthorseman

    Lighthorseman Active Member

    You Guys Are FAST!!

    Wow! Look at that, eh? Answers even as I was uploading pictures!

    I love the warped roof effect - but only as long as it is appropriate.

    I had a look at my old feed mill, and, sure enough, as per Ben King's instructions, the roof was cross-braced with stripwood. The warp occurred as soon as the bracing ended.

    I will be sure to properly brace and place under weights any roof section that needs to be straight, and let you know how it worked.

    Thanks so much for the answers. Perhaps a seemingly simple thing, but I'll admit - it sure had me stumped.
  7. jkristia

    jkristia Member

    That is one beautiful scratch build feed mill :thumb: :thumb: :thumb:
  8. jon-monon

    jon-monon Active Member

    Could also grab an empty beer can and cut a sheet of thin aluminum to glue the roofing to instead of a softer warpy material.
  9. Fred_M

    Fred_M Guest

    White glue and paper. The glue shrinks as it dries. Roof warps. Bracing it up as said above works as does switching materials. I use clear silicone RTV from the autoparts store for adhesive and it eliminates warpage for me. Here is a roof that was made from a piece of cerial box with over 100 corregated foil pieces stuck to it over 6 months ago. No warpage and no braces. No clamping or pressing. And the foil sticks really hard, I don't think it could be removed without destroying. And silicon is cheap, less than $3 a tube around here. It also sticks wood, plastic, plaster, metal, everything I ever tried. It also was used to glue the cedar shingles to cerial box in the building behind, but I can get a clear pix of it due to scenery. FRED

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  10. billk

    billk Active Member

    How about using that Ailene's Tacky stuff instead of white glue - I know it dries kind of flexible.
  11. TinGoat

    TinGoat Ignorant know it all

    Art-School trick

    Hi Steve,

    For doing watercolour painting on thick stock... Paint the backside of the card first with Latex paint.... The card will warp one way and then when you work on the good side, the stock will warp back to being flat....

    I don't think that the glue is shrinking exactly... It is the water content of the glue that is causing the paper to expand first. And then, when it dries, it is trying to go back to its origional size....

    Another method is to make sure that everything is sealed first... Paint both sides of card stock first and make sure that every thing dries flat...

    Then cut and bend the matial to shape and glue on thhe shingles...

    Also, use spray adhesive like photo mount, instead of white glue....
  12. Lighthorseman

    Lighthorseman Active Member

    Well, off we go again. This time, I'm trying to create a roof for a building - a small shack, actually, for the diorama contest. I've glued reinforcing stripwood to the back of the roof, and I have put on the tarpaper on the roof, using a fine black sandpaper.

    As soon as I put it together, it started warping...again :curse: and is currently sitting under a large pile of heavy hardcover books. I guess we'll see what we end up with.

    If it still doesn't work, what about the idea of almost saturating the wood, and re-weighting it?
    Anyone know if that might work? :confused:
  13. Fred_M

    Fred_M Guest

    :) I repete, try silicone adhesive. FRED
  14. Lighthorseman

    Lighthorseman Active Member

    I'll tell ya, Dash - If this doesn't work, I'll be picking some up tomorrow. :thumb:
  15. boppa

    boppa Member

    just a thought-if its the glue on one side causing the warping-glue both sides?? might reduce the warping
    worth a try maybe
  16. Hey, Steve.... :wave:

    Great looking work. Those shingles really give it that special FX. I had the same problem some years ago. I bought an old On3 Grandt Line Colorado & Southern stock car kit and when I opened it uo...TA-DA! Warped roof AND warped floor. :( Well, at least it wasn't twisted. I ended up working with the warp and it came out to be rather realistic when it was weathered. :)

  17. Gary Pfeil

    Gary Pfeil Active Member

    I could be wrong but believe that once a roof is warped you're not going to unwarp it. Tingoat's suggestion and the bracing are good one's for new construction. I suggest you build new roofs. Keep the old ones for photos if you like.
  18. Vic

    Vic Active Member

    One Way To Snag The Sag

    Steve,From looking at your pics it appears that your roofs lack a ridge pole that would support the center of the roof. For modeling purposes a ridge pole can simply be a square stick of the apporiate size rotated to match the angle of the slope of the roof as indicated by the slope of the end gables.

    This way you can make your cardboard or what ever material roof in two pieces with them meeting at the center of the roatated ridge pole. The addition of rafters will eliminate sag on the face of the roof too.

    Hope this crude drawing helps.

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