Tarpaper Tutorial


The first thing to do is decide what method and pattern to use. I’m “rolling” out the tarpaper laterally across the main and clerestory roofs with a scale 6” overlap. I used a “tee”-square to layout the lines drawn with pencil on the model using the width of my tape (36mm) as the spacing factor. I started at the center of the car and worked toward each end – the same way I’ll lay out the tape.


Mark the pattern on the clerestory roof first and then align the main roof sides with a “tee”-square. You can “eyeball” it if you want, but this is a little more precise.


Peel off a length of tape and lay the first course between the lines.


If you haven’t done so already, now is the time to put a new, sharp #11 blade in your hobby knife.


With your fingers, press down on the tape and smooth it out so it conforms to the shape of the roof and sticks tight (I used “High Tack” masking tape from 3M.) Be sure to do the same on the edges (eaves.)


Then, use a fingernail or some other “semi-sharp” object (like a toothpick) to snug the tape up under the eave, butting up against the fascia board below.


Trim off the excess, using the 90º angle between the roof underside and the fascia board as a guide for your blade tip. Do both sides, of course.


Here’s what it should look like when done.


Using the pattern you’ve laid out, stick the next course of tape to the roof with about a 4mm overlap. (Keep it straight.)


Repeat the process described above.


Before moving on to the third course, run your thumbnail along the edge of the first layer (now covered by the second) to snug down the tape and better define the ridge of overlapped tape. Don’t forget the sides.


Here’s what you want before you move on.


Continue the process along the length of the clerestory roof.


When you get to the duckbill, do the same thing, just take your time to make sure the tape is pressed down smooth, without wrinkles. Stop here on the clerestory for the moment and go back and start the main roof sides.


At the course where you started on the clerestory, stick the first course of one of the main roof sides.


Use the angle between the roof and the bottom of the clerestory as a guide to trim the upper part of the tape. Continue on both sides, in both directions, as on top.


When you get to the point where the upper and lower courses merge, run the next courses across the full width of the roof until you get to the end.


Here’s a close-up of the merged courses.


On the last course at the end, do the sides first and then fold the tape over the end eave and butt up against the fascia like this.


If you need holes in the roof for stove pipes ‘n’ stuff, it’s best to drill them first…


…and then use the opening to help trim the tape.


When you’ve finished laying all the courses of tape, the next step is crucial for properly sealing your roof, making it weatherproof. I use “Instant Krazy Glue” by Elmer’s – it’s not exactly a gel, but not as viscous as regular ACC glue either. It’s a “brush–on” type with an applicator built into the cap and goes on purple in color but dries clear.


Use the built-in brush to run a liberal bead of glue covering every exposed edge of tape. (It’s not necessary to seal the edges covered by the overlaps, however.) It should dry pretty flat, but if it doesn’t, it’ll just simulate the hot, liquid tar used to seal the real deal (I like that) when it's painted black.

Don’t forget to seal up under the eaves. This process not only seals the seams but makes the roof covering a single unit and prevents individual courses of tape from peeling back in case the “stickum” fails or the tape shrinks in the sun.

Well, that’s about it. Once the Krazy Glue is dry, give the whole roof a light sanding to smooth out rough edges and you’re done. When ready, prime and then paint with “Engine Black” followed by a dry brushing of “Grimy Black” and, perhaps, a light, dusty tan color to make the texture and seams really pop out. Finally, a couple of coats of Testor’s DullCote will further seal and protect your roof.


Here's a shot of the roof of another car I finished using this method, to give you an idea of how the paint looks: