I am putting the finishing touches on a n scale shack that has rolled roofing. I have one coat of polyscale black on the roof. The plan was to put a second coat of the black and sprinkle some z scale dark gray ballast in to represent gravel on the roof. the problem is the black paint is drying very quickly so I dont think there will be time to paint the entire roof before applying the balast, I though about using diluted elmers instead but I am worried it could result in a glossy finish. does anyone have any other ideas?
I have heard of using strips of toilet paper or tissue paper. If you think the paint is drying to fast for you to paint a strip then apply and adjust the paper, put a little paint at each end and in the middle, when the paper is in place, lightly paint over it. Unless you are representing a new roof, you will want some spots that look faded and worn.
If you want the effect of granules on your roof I suggest using very fine grained sandpaper instead of trying to apply your own materials. By fine I mean really fine - like 1600 grit. It will give only a suggestion of the granules being present but that in reality is what you are trying to do. Even with that fine a sandpaper the actual grit size will be way too big for N scale, but at least it won’t look toy-like. I don’t recommend painting over it with anything except perhaps a light coat of Dullcoat. Even that will likely mask the granules.
I model in HO and I have several buildings with rolled roofing. I used strips of manilla envelope. The granule is left to the imagination but the overlapping joints show well enough to get the message across. I personally am reluctant to use sandpaper because cleaning dust off it without leaving marks would be next to impossible. Flat paint is all I use for the finished colour.
You will only get a reasonable represenation of any fine gravel since to actual scale in “N”, would be like the 1200-1600 grit wet or dry. The only problem is that the sandpaper will still need some painting and weathering. This coat of paint will obscure any of the grit and it will just look like rough paper. To ballast the roof in even z gravel will look like a hot mop/ gravel roof.
You could try the coarser grit of about 1000/ 1200 and experiment w/ washes not a coat of paint. I would suggest using thinned solvent not acrylics as the water could cause edge curling.
If you still wany to secure the z ballast, don’t worry about any sheen from the glue, just dullcoat. Or you could use matte medium (no sheen)
Elmers mixed with black paint can be used to make tar seams and seals for around chimneys and at the edges of the walls. It would be hard to do this in N scale, but in HO I mix up a small batch and then use a tooth pick to run beads of it around things. I would think that black painted fine grit sand paper with beads of this stuff would make a good representation of what you are looking for.