Slow Bridge Ahead

[Dave V]

I dunno Rob, I think you're being way too hard on yourself.  I probably would have made the road from an old styrene garage sale sign and shot it with some Dark Aircraft Gray, striped & weathered it, and called it a day like this:



I applaud your attention to detail, but when the work function exceeds the fun function, you've missed the sweet spot:

[Zox]

I applaud your attention to detail, but when the work function exceeds the fun function, you've missed the sweet spot:

True, but what really annoyed me about this was (a) I was ready to move on to the next step, and (b) I thought I'd adequately proven this roadlaying method on the Area 53 modules. I didn't realize that the minor changes would all interact to cause a small yet obvious failure.

One of the advantages of doing the road on the computer is that I can recreate it exactly, simply by reprinting it. If I'm very careful, I should be able to replace the damaged area with minimal evidence of seams. That'll be my near-term project.

[DKS]

You can still reproduce the road on your computer, yet have a very stable surface, by printing a large waterslide decal and applying it to thick styrene...

[Mark5]

Sweet!

[Zox]

The road on the front side of the module started wrinkling up just before the October Timonium show, and as of tonight was a lot worse.

As a visual aid, here's what the area looked like before I started surgery:



So far, I've peeled off the paper, cut out the portion of styrene underlayment that failed to adhere, glued in a replacement piece, reinforced the joints, and added an overlay to stiffen up the rest of the underlayment.

After updating my Windows 7 printer drivers (so I could actually color-match the road to the one I printed under Windows XP), I've now got the replacement road Dullcoted and drying in the basement. This repair job must be done by December 9; I'm actually hoping to get it done this weekend. I'll post some pictures of the deconstruction and reconstruction when I have a chance to choose some decent ones.

So far, my main lessons learned are:

(a) I needed to use a thicker styrene layer for the underlayment. On my Area 53 module, I used 0.020" and had no problems. On this job, I used 0.010" because I didn't think the extra thickness was necessary, and putting the "crown" in the road was easier with the thinner styrene. Obviously this wasn't a good choice.

(b) One area under the styrene had a piece of blue masking tape within the "sandwich" from the assembly stage, and that's where the primary failure occured. I thought that the glue I added later would adhere it permanently, and a similar patch elsewhere is perfectly solid, but it would have been safer to remove it.

(c) The "permanent" spray-mount adhesive is brittle and will powder if it's flexed; in this application the "temporary" adhesive works better because it's more flexible. While I've had some edges peel up on Area 53 where I used the "temporary" spray, it's a simple job to tack them down with a spot of CA; the "permanent" spray failed clear across, and there was no way I could re-glue the middle without peeling off (and mangling) the paper.

[Zox]

Bringing this up to date, as of tonight, when I had to load the module in the car for this weekend's show at South Columbia Baptist.

After cutting the right-hand sidewalk loose along the curb and peeling it up from the paper, prying and peeling the paper loose from the styrene, and cutting out the portion of the styrene where the underlying glue had failed, I was left with this:



I made sure the remaining styrene was securely superglued to the foamcore underlayment, patched in the hole with 0.010" styrene, and added an additional layer of 0.010" styrene to the "old" styrene to reinforce it. I then used 0.005" styrene to reinforce the seams between the patch and the new surface, and to smooth the transition of the new surface down to the old level under the bridge:



Unfortunately, I was unable to color-match the new road to the old one--apparently the Windows 7 drivers don't work exactly the same as the XP drivers.

However, I did have an entire replacement road sitting around, already mounted to styrene, that I had made back when I did the original work. It had a problem with the side road, which is why I'd abandoned it back then. But I figured it was better to have a color-match problem between the side road and the main road, than to have the problem right in the middle of the main road. (And I may be able to fix it later, since the affected area is out in the open instead of buried under the bridge.)

I cut the damaged side road off the replacement, then spent a considerable amount of time trimming the replacement to fit between the curbs--it was originally designed with the curbs over the road surface, but that obviously wouldn't work for the retrofit.

Finally, with the replacement spray-glued (with the repositionable stuff) to the module, the corners tacked with superglue where needed, and a bit of new pavement added for the side road, here it is: