duminică, 20 iulie 2014

More Electrics

Realized at one point that since there's no map of how each wire goes where, not to mention that some of the wires lost their purpose during the time since not all of them were marked - that it's gonna get complicated soon if this isn't rectified. So there have been quite a few hours over this months of mapping out what goes where. A Visio diagram was also employed, and each wire colored as it is on the layout, complete with tool-tip comments that show a wire's function when hovering over it.
Work was done to the electrical panel that will contain all the modules (Viessmann, Phidget, etc.) so I can finally move away from the wiring-in-a-box approach
Last but not least, since it turned out that quite a few wires will be required in the end, no less than 4 D-Sub connectors would be needed (37 pins/ connector, however because I'm using some 32-wire legacy cable, 5 of those pins will go unused). The required connectors, brackets and various other items were purchased;  so far a connecting cable was built, the original connecting board got modified so that it holds 2 connectors, and a new enclosure for a similar cassette plus the corresponding board were just finished today.



duminică, 9 martie 2014

Precision Earth Test Patches


As stated previously, the precision scale recently bought was instrumental in creating a test board, with 8 patches of earth formula. This is simply a 1-cm thick foam board, on top of which one sheet of plaster cloth was applied - both to provide better grip for the zip texturing to come, and to replicate exactly the layout structure. The starting formula was the now classic 5 parts plaster, 1/5 parts burnt sienna dry pigment, 4/5 orange dry pigment. Each patch has a known ratio of blue ultramarine pigment, which was increased  in small doses against each one. For each patch, the procedure was similar - wet the spot with white glue, apply the corresponding formula with a tea strainer, leave to dry for 1 hour, then repeat again in the same location, then move on.

  After adding the determined weight of blue ultramarine dry pigment - usually around 0.04 grams - the whole formula would be thoroughly mixed in a "shaker" for 4 minutes, as to ensure a uniform outcome (the days when I would use a spoon to mix things are long since gone - since applying the resulting mix resulted in particles of the stronger pigment - then black - "shining" through the whole formula).
  As the last patch on the first test board was still not matching the medium earth color on the layout, I decided to extend the batch of tests on another test board. Photos 2 and 3 show the first test board and second one, respectively. The white spots on the edges of the patches represent white glue, migrating from the patch under work to the previous one(s), already finished. Not a big drawback since the colors can be matched like this with no problem. The 2nd board still needs to have one application over the 7th patch, and the last one completed.

  For both boards, the order of the patches if left to right on the top row, then right to left on the bottom row - so that the 1st one is on top left, while the 8th one always on the bottom left. 
  The percentages of blue ultramarine dry pigment is as follows: 1st test board - patch 1: 0%, patch 2: 0.1%, patch 3: 0.22%, patch 4: 0.43%, patch 5: 0.61%, patch 6: 0.9%, patch 7: 1.2%, patch 8: 1.6%. 2nd test board -patch 1: 1.8%, patch 2: 2.0%, patch 3: 2.2%, patch 4: 2.5%, patch 5: 2.8%, patch 6: 3.1%, patch 7: 3.3%, patch 8: 3.5% (patch 8 not visible in the photo at this time).

The last photo shows both boards alongside, just to get an idea of the color ranges in both.

duminică, 9 februarie 2014

Precision Scale

Even though I've revisited the earth formula here, I never really managed to make a true "formula" - one that could be replicated time after time, using precise measurement. As a result the various earth patches done so far on the layout vary in various degrees. Since I've been having a hard time matching colors with different batches lately, I've decided it's time to take things further and bought a precision scale. It can measure in increments as small as 1 milligram, so hopefully this will be good enough to replicate various dry pigment formulas over and over again. At 20 pounds, it's actually a good price - considering it actually has that 1 mg granularity observed after some testing. The photo shows this little device at work, while I was adding small amounts of ultramarine blue to the old earth formula (5 parts plaster, 1/5 parts burnt sienna, 4/5 orange). This has to do with a small test board made from a piece of foam and a sheet of plaster cloth applied on top - its role being that of sampling various combinations and writing down the various ratios involved. 
Why blue pigment instead of pure black one to make the formula slightly darker ? 2 reasons: the complementary color of the light brown-ish color that my earth formula has is actually blue, as seen here (a hue plus its complementary color will yield black in color theory when applied to pigments as stated here), secondly, I've never experienced this combination before (I've been adding only black pigment until now).

sâmbătă, 27 iulie 2013

Finished Brawa Platform

First described here, the Brawa platform is now almost completed - first 2 photos show the status captured minutes ago. The asphalt cracks are partially filled with some winter miniNatur static grass, probably some autumn model will be added too.For asphalt, a hard foam was used (photo 3) - this has been originally used to package the Noch tunnel lining and came quite handy now. Various cracks and dents were applied, to simulate as closely the real surface. The color was obtained as follows: first, all was painted with Woodland Scenics (WS) Stone Gray; after this dried a series of washes was applied, only after the previous one completely dried, in order: 1:8 WS Concrete, 1:8 WS Burnt Umber, 1:8 WS Yellow Ochre, 1:3 WS Stone Gray (as opposed to the rest, this was applied perpendicular to the length of the platform), 1:8 WS Yellow Ochre. After the first yellow wash, some Noch black weathering powder was used to break the monotony - even if this looked too powerful at first, the subsequent washes toned it down just right.
After painting, the soldering gun was used (photo 4) to take away from the edge, so that it will bind correctly with the platform edge which was already fixed. The groove of the thermocutter was used to hold the foam in place. 2 supports were made from regular foam in order to support the platform once fixed (photo 5), after which it was glued, with the same Woodland Scenics color containers that were previously used for washes pressing down (photo 6). The angled platform ends were painted in the same way, then fixed.




Hints


Over the time, I've been compiling quite a list of small notes, consisting of small hints and some activities that should eventually make it to the plans for each section of the model railway. Since every time I run into the pile I keep reading the same things - I've decided it's time to put the hints somewhere, and the activities to their respective plans. Hints are centralized below.

 1) When unmounting a point switch, it's more easier to simply gently lift the tile where the motor rod connects (2nd photo) - like this there's no need to go underneath and unscrew the "cheese" screw that clamps the rod to the point motor mechanism. If not doing this too often, the hole in the plastic tie shouldn't get larger in time
2) The plaster cloth "lids" should have a non-uniform contour, so one cannot easily spot the difference in height
3) To provide access to various wires underneath the terrain, buildings with removable roofs can be placed on that spot
4) A landmark for plaster cloth "lids" can be achieved by gluing specific plants on the terrain supporting it, so when the lid must be placed on the layout, there's no doubt about its final position
 5) The Noch glue, used for the static grass, is diluted 1:2 glue to water, so the there's no visible difference in the terrain color after this dries, especially at the "border" zone between the original terrain and the one that was soaked
6) The static grass should be pressed down lightly next to a figurine or on paths where there's supposed to be traffic
7) On areas where a plaster cloth "lid" will be applied next to a segment of track, there should be a minimum of 3-4 cm sideways from the foam support underneath the track - this will allow the edge of the lid to sit over the terrain, but not to close to the track itself (where ballast usually lies - making "hiding" difficult)

8) For the switch connecting segments D with C/SR, the "cheese" screw can be accessed with a long screwdriver, as seen

in the 3rd photo
9) For the same switch, removing the Tilling 86112 can be done using a mirror, placed like in the 4th photo, and using a curved screwdriver for the 2 screws holding it in place
10) The mobile rod for a switch motor can be easily removed if the point is brought into a "half-switched" position - this can be easily achieved by turning off the power for the switch motor, modifying the Phidget controller, then powering on briefly so the motor doesn't do the complete lap

marți, 23 iulie 2013

Artitec Oil Cart

Got a new order last month from LokShop that also contained an Artitec oil cart. Looks like Artitec is suggesting 2 color schemes - one with a bright orange for the barrel, the other, more natural, sporting a grey mettalic finish - as seen here. I opted for the latter. First photo is the small original package. Same as with the Artitec lantern building, the burrs need to be removed, this time using a combination of file and cutter. The second one shows the elements to be painted black - the chassy, supporting brackets, the wheel axle and the already masked (with 3M Vinyl Tape 471+) barrel. Last photo shows the progress over the parts to be painted in a wooden color - Tamiya Desert Yellow (XF-59) was used in 3 layers. Next up will be the piece that resembles a set of small oil canisters, located in the back of the cart itself, and finally the metallic parts - the barrel and the metal band on the wheels. Finally drybrushing along with some weathering will be used to finish it.





sâmbătă, 8 iunie 2013

Switch Issues

Soon after fixing the problem described here, I was worried that the same issue happened to one of the switches in the PT pair (M31), which experienced the same symptoms of poor electrical connectivity when part of the locomotive wheels were in the frog. Turns out it was only the Tillig 86112's brown wire that came loose from its connection with one of the wires providing power. When this happens, the voltage measured between any point of the frog and its opposing rail will be at about 6-7 Volts.
With this out of the way, I turned my attention to the switch in front of the tunnel, which started making a powerful noise for quite some time now. Opening the switch, cleaning it with the airbrush (blowing just air) and removing part of the components indicated that the motor was not at fault, and the cause of the noise was actually a broken cog - the hairline crack is visible in the first photo - not something that bad, but big enough to make the gap between those 2 teeth generate a considerable noise when being driven by the motor's worm drive. The whole component is present in figure 2. Luckily some time ago I've ordered a spare 86112, so the fastest way to fix the problem was simply switching the whole rod that contained the broken cog. Comparing the 2 switches (photo 3) showed no visible difference in this, but contrary to my memory, it's not just the color that was different among the first switch drives I bought and the subsequent ones - actually the motor itself is changed, and comparing the sounds one can immediately notice that the new ones are far more quieter. After everything was reassembled on the old drive and small amounts of silicone grease applied, I've placed the old rod and the components of the new drive (that interact with the rod) in one of those dynamic-compartment types of small plastic boxes, one of which I bought today.