NE Brownstone Viaduct

[deemery]

The primer is also the mortar color.  I'm using "Bob Ross" grey gesso, thinned a bit.  You want this to completely color the mortar lines, so it's important to work it into all the cracks.  At the same time you don't want this to fill in any relief, so I go back and forth with the brush to get good but thin coverage.

After this dries, I'll sponge paint the stone colors.

dave

[Lynnb]

I bet there is a fine line when it comes to thinning enough to still get good coverage, not thin enough and you loose the details.

[deemery]

And that fine line varies a lot with the brand/kind of paint.  You can thin oils more than acrylics.  You can thin artist acrylics more than craft paint.  The thing about gesso is that it has something (I think very fine marble, like gouache) to provide a good base for the subsequent paint layers.  So it will go on a bit thicker than other artist acrylics.  But it thins well.  I use water with Liquitex Flow-Aid mixed in.  I keep that in an old contact lens solution dropper bottle, to make it easy to add small amounts of water to the paint. 


dave

[Zephyrus52246]

Dave, with the door there, is this a lift out, swing out or a duck under?  The bridge looks great with just the initial color coating. 


Jeff

[S&S RR]

Dave


I really like the look of the viaduct. Very nice work.

[deemery]

That door leads to the electrical panel closet the damn building inspector made me install.  The section is designed that it -could be cut out- if absolutely necessary.  It's basically "inverted benchwork" in that the joists sit on top of the plywood.  But that makes a nice platform for a river, and when Russ Greene told me about his viaduct plan, I knew that's the bridge that would go there.  Russ sent me sketches and measurements so I could be sure the track was straight for the appropriate length.

For now, it's only a duck-under when I need to reset a breaker. 

dave

[deemery]

My approach for doing stone is to drybrush various colors of (craft) paint using make-up wedge sponges.  This allows me to get paint on the top of the stones without the paint getting into the mortar cracks.


This set of photos shows a progression, I'm about 1/2 through.  I tend to alternate light and dark colors.  I need at least one more lighter base coat color, then a top-down drybrush with a very light/off-white color to add highlights.  The bridge right now lacks contrast and "pop."  (Then I start with chalks/Pan Pastels.)  But since I've run out of make-up sponges, that's enough for tonight.


dave

[Pennman]

Dave,
I'll add to all of those in agreement above.  I like what you're doing with the bridge and actually having access to the breakers.
Also, I just love NE Brownstone castings. They make great walls and this bridge is also an eye opener for sure. Great work and
thanks for the expert instruction.

Rich

[deemery]

To finish up the coloring.  I thought the overall effect was too flat grey, so I did a rather heavy coat of a light buff color.  Then I mixed some light grey, white and water, to get a transparent light grey to tone down the buff.  I used an off-white to dry-brush highlights using a bristle fan brush (hard to find, but worth it for these kinds of applications.)

Then I moved to chalks/pastels.  These give me good control to color individual stones, as well as some random splotching.  I turn pastels into chalk with a small piece of wallboard sanding screen.  I picked up some color on a brush, applied to an individual stone and spread it out over the stone.  I also rubbed a pastel on a stone and used a "Colour Shaper" (a rubber tipped paintbrush) to spread the pastel over the stone.  This gives great control.  See https://www.rexart.com/colour_shapers.html  Finally, I stippled random colors of chalk over the stone. 

The bridge looks a lot better on location, the stones have more depth to them.  That's it for now.

dave

[Dennis Bourey]

Beautiful Job, Keep it up.........

[GPdemayo]

Great work Dave.....

[PRR Modeler]

Great coloring so far.

[deemery]

Did I sufficiently answer the "how do you color the rocks?" question?


dave

[cuse]

Dave,


You're doing a fantastic job. I'm about to sign off and go do some measuring of my own. I'm surprised there were such difficulties with "gaps" even after gluing it and using clamps...could there be a better choice of glue for the castings.


you mentioned that there is a slight curve in the track (and, therefore, the bridge)...did you simply file away the meeting points between bridge castings until you had the necessary "curve"?


Looks great. Thanks!


John

[deemery]

...you mentioned that there is a slight curve in the track (and, therefore, the bridge)...did you simply file away the meeting points between bridge castings until you had the necessary "curve"?
...

That's exactly what I did!  I have a full sheet of sandpaper glued to a 1' square marble tile (so it's guaranteed flat.)  I sanded the arch (which has the "plug") until I got the right angle.  Then I used a regular file to sand down the pilasters on the abutment so the arch fit tightly.  Definitely "sand a little, test a little." 

One advantage I had was the inside joint (where you'd see a bad fit) is on the non-visible side.


And on gluing:  It wasn't a problem with my glue.  The glues I used (good quality PVA and then epoxy) held tightly.  The problem is with the plaster itself.  It doesn't have sufficient internal bonding strength.  So what happened was that the glue held but the plaster behind the glue gave way.  I've talked to Russ a bit about ways to make that joint stronger, but there's no easy solution.  Russ said, "It's not a problem if you color the castings before assembly and then glue it in place."  He's right about that!  (But that's not how I wanted to do it.)

dave