hornblower Another technique for hiding seams in styrene road surfaces is to make them look like road repairs. Instead of cutting perfectly straight and square edges where two pieces of styrene road meet, try cutting the edge of one piece in an irregular pattern, kind of like a large crack you see in a real street. Next, place the edge of the next piece of styrene road under the first and trace the irregular edge shape onto the next piece of styrene. Cut out the irregular shaped edge in the next piece of styrene, then fit the two pieces together like puzzle pieces and glue then down to the layout. Use caulking or WS Foam Putty to fill any gaps between the two pieces. Don't worry about achieving a perfectly flat suface as we've all driven over lumpy road repairs. When you paint the road surface, you can even paint over the "repair" with a darker gray to resemble fresher asphalt patches.
Another technique for hiding seams in styrene road surfaces is to make them look like road repairs. Instead of cutting perfectly straight and square edges where two pieces of styrene road meet, try cutting the edge of one piece in an irregular pattern, kind of like a large crack you see in a real street. Next, place the edge of the next piece of styrene road under the first and trace the irregular edge shape onto the next piece of styrene. Cut out the irregular shaped edge in the next piece of styrene, then fit the two pieces together like puzzle pieces and glue then down to the layout. Use caulking or WS Foam Putty to fill any gaps between the two pieces. Don't worry about achieving a perfectly flat suface as we've all driven over lumpy road repairs. When you paint the road surface, you can even paint over the "repair" with a darker gray to resemble fresher asphalt patches.
Good points.
Here is a picture of a concrete ramp meeting an asphalt road:
Here is a picture of multiple patches:
Rick
Thanks for the ideas. Another application is to attach Plastruct brick or stone sheets to styrene. I don't anticipate problems with smaller areas but I'm not sure about working with large sheets of say 6" x 12". Would it be best to tack a number of spots instead of applying adhesive to the whole surface?
Hornblower
hbgatsfDo you wait for the lacquer thinner to dry before applying the contact cement or does it need to be wet?
I decided to try applying the lacquer thinner simply to make application of the contact cement easier, and I put it on quite liberally, so it's still somewhat wet when I start adding the contact cement. It was just an experiment to see if it made application of the contact cement easier, and, in my opinion, it seemed to work quite well.
Wayne
doctorwayne I use 4'x8' sheets of .060" thick styrene, and "prep" the styrene using lacquer thinner (usually applied with a 2" brush) then brush-on gelled contact cement - the lacquer thinner reacts with the plastic to make application of the contact cement much easier. After brushing the contact cement onto the plywood, I wait until the contact cement on both the plywood and the plastic is dry to the touch, then carefully bring the two surfaces together. (If you're uncertain about getting the piece of plastic properly positioned, cover the contact cement on the plywood using waxed paper, which will allow you to jockey the plastic into place, then carefully withdraw the waxed paper, pressing the plastic into place as the waxed paper is removed. Wayne
I use 4'x8' sheets of .060" thick styrene, and "prep" the styrene using lacquer thinner (usually applied with a 2" brush) then brush-on gelled contact cement - the lacquer thinner reacts with the plastic to make application of the contact cement much easier. After brushing the contact cement onto the plywood, I wait until the contact cement on both the plywood and the plastic is dry to the touch, then carefully bring the two surfaces together. (If you're uncertain about getting the piece of plastic properly positioned, cover the contact cement on the plywood using waxed paper, which will allow you to jockey the plastic into place, then carefully withdraw the waxed paper, pressing the plastic into place as the waxed paper is removed.
Thanks. That is something like I originally thought of doing it. Do you wait for the lacquer thinner to dry before applying the contact cement or does it need to be wet? Have you tried eliminating that step?
I did a test and glued some small pieces of scrap styrene to plywood using Elmers Wood Glue and Titebond II. Both seemed to adhere well enough for this application. The advantage I see of this is you get some working time to position the styrene but I don't know if a large piece of styrene would work out the same way.
I buy styrene signs at big box stores. They are the same material as "sheet styrene" and often less expensive on a cost per area basis. If you are going to paint the styrene anyway, it doesn't matter if "For Sale" is already painted on the signs.
I use Plastruct liquid glue for bonding plastic to plastic. I primarily like the glue because it bonds the PLA plastic I use for 3D printing. Few other plastic glues work with PLA. As long as I already have the Plastruct glue, it works great for styrene too.
To glue the styrene to other surfaces like wood, I "score" the back side using a wire brush to make it "rough". Glues that don't dissolve the plastic need a "tooth" to grip. If you try to glue smooth plastic, it will eventually sheer free of the glue. Also, fingerprints on smooth plastic will prevent good bonds with glue. Even just setting a can on the plastic can break the glue joint with smooth plastic.
I have used Gorilla Glue, but I don't like the way Gorilla Glue expands as it cures. I recommend plain old yellow wood glue combines with a rough surface for it to grip.
Prototype:
https://nscale4by8.github.io/nscale4x8/
Weldbond says it all, emphasis on "weld". The adhesive is polyvinyl acetate (PVA). Once it dries, you may never be able to remove the styrene sheet from the plywood if you later decide to re-do that portion of your layout.
Honestly, white glue will hold down the styrene sheet securely, and yet the styrene sheet is removable if need be. As I mentioned earlier, I use Woodland Scenics Scenic Glue with excellent results.
Rich
Alton Junction
I found this old thread about attaching styrene to wood with Weldbond.
https://cs.trains.com/mrr/f/11/t/231048.aspx
(I don't know why inserting the link doesn't work.)
Now that many years have passed have any of you had issues using Weldbond? Has it held?
For seams, try using a doubler on the back made of .010 styrene. Then you can fill the visible seam if you want using styrene putty (Squadron and Tamiya are two makes). After filling, sand the putty down and when painted the seam disappears.
I did this on my backdrops (though I used a .080 doubler for the joints between sections for strength - thickness wasn't an issue) and the seams are invisible.
Mark P.
Website: http://www.thecbandqinwyoming.comVideos: https://www.youtube.com/user/mabrunton
I have had good luck using transfer tape, a very thin version of double sided tape, no thicker than ordinary "scotch" tape (and indeed 3M is a manufacture of it). Since it has no solvent or liquid component distortion and marring of surfaces plays no role. Sometimes I apply it to both sufaces for a really solid bond, but then it tends to be "one chance and you're done."
Scribing the gaps between concrete sections probably results in a more realistic slight gap than using separate sheets anyway. By the way sometimes you can get sheet styrene rather cheaply if not free at a sign shop -- their "mistakes" or leftovers.
Dave Nelson
Plastruct Plastic Weld!
Look no further, this is what you want to bond styrene sheet to styrene sheet. I got this recommendation from my buddy and fellow forum member, Frank, aka zstripe, some years back.
Apply it to both edges, or sides, of both pieces and act quickly because it dries fast. It comes in a clear glass bottle with an orange label. There is a brush applicator in the cap. Just be careful not to tip over the bottle.
As for bonding styrene sheets to plywood, you really don't need stuff like contact cement or clear glues. What I use for all my streets and sidewalks is Woodland Scenics Scenic Glue. Apply a thin coat to the plywood surface, and you are good to go. I spread it evenly with my finger. It comes out of the squeeze bottle white and dries clear.
Check the adhesive on a small sample, if it is solvent based it can warp or distort the styrene.
Using a splice plate of scrap styrene at the seams locks it in place.
Dave H. Painted side goes up. My website : wnbranch.com
I have ordered 24" x 48" .060 styrene sheets to use for streets, roads, and general projects. The size of the sheets will minimize the number of joints in the streets but there will still be some. Is there a trick to getting perfect alignment along a foot or so making the seams less noticeable?
What would be the best adhesive to use to bond it to plywood? I was thinking of using contact cement like is done with countertops.