Two-level lift gate - Part 1 of 4 (criteria)

 In the period January through April 2019, I posted a series of seven articles about the design, construction and operation of what I call my "No Duck Mo" which is a Free-mo module ("mo") containing a swing-up lift bridge so people can pass through a Free-mo layout without having to duck underneath the modules ("no duck").

In March & April 2020 I introduced my current basement layout, the Wascana Canyon Railway ("WCR"). The WCR consists of three levels, the lower being along the wall and the middle and upper levels are along three walls and connect into a loop about 2/3 of the way down the room. Here are the track diagrams for the middle and upper levels:

Both levels have what is described as a "two-level lift gate". This means I was challenging myself to design and construct a new version of my No-Duck-Mo but this time it needed to have two levels which opened and closed simultaneously.

Design Criteria

I set out to design this with the following "must-haves" in mind:

1. Both gates must lift and lower simultaneously and lock safely into the raised position when the gate is lifted.
   
   
2. Resistance to the force of gravity. Two gates, each of which would be about 30 inches long and around 11 inches wide, would be heavy because not only are there are two of them but they must also be sufficiently robust to resist sagging, twisting or warping. I wanted to be able to simply give the open gates a slight push to begin lowering gently without slamming shut. This is also a safety feature to avoid the gates smashing hard onto someone's head in the event that the gates become unlatched from their raised position while someone is walking through the opening.
   
   
3. Flawless alignment of rails.
   
   
4. Reliable track power to rails on both decks (the lower level is double track mainline and the upper level is single track) including power cutoff to 40 cm (1.3 feet) of rail on either side of the gate when it is open to prevent trains from falling into the abyss.
   
   
5. Mechanical barriers that automatically close when the gate is opened and open when the gate is closed, again for the safety of rolling stock and to protect fragile egos, mine included.
   
   
6. Warning lights to attract attention when the gate is open.

In future posts, I shall outline how I achieved all of the above in my design. I completed construction in the winter of 2019/20 and my two-level lift gate has been working flawlessly ever since.

Continued in Part 2 of 4.

Voltage Any Way You Like

My modelling projects involving electrical components require a certain voltage value which invariably differs from whatever power supply I happen to have on hand. For example, the Arduino microcontrollers I use require 5 volts of regulated power if they are powered directly to their 5-volt inputs.

Over the years I have made my own voltage regulator circuits but always run up against the issue of wasted heat which needs to be drawn away from the voltage regulator using a heat sink and, even then, I worry about the potential fire hazard.

Not long ago I was listening to an episode on Larry Puckett's YouTube channel called Model Railroading With The DCC Guy. Larry makes frequent posts on a variety of topics, most of them electronic, and does a good job of explaining everything in layman's terms.

Larry's episode 120 covered the use of buck converters. These are little circuit boards that convert one DC voltage to another. The desired voltage is set using an onboard potentiometer which is turned with a small screwdriver. I ordered a batch of 10 from Amazon for C$19.99 and free shipping, so the per-item cost was C$2.00.

As you can see this one will use any DC voltage from 3V to 40V and reduce it to 1.5V to 30V. and it can handle up to 3 amps which is more than enough for most of our projects.

Here is a picture of one hooked up to a 9-volt battery. The voltage has been adjusted to 5 volts. The adjustment is very precise and allows for adjustments of 1/100 of a volt which is more precise than what I need. To run Arduinos on my model railroad I will be powering these from the 12 volt DC regulated power supply that is present under all of my benchwork. When connected to an Arduino these buck converters product no heat detectable by my finger.

From my search of Amazon and eBay it is clear that these can be purchased in many different configurations including those that can boost voltage.

Lytton Catwalk in British Columbia's Fraser Canyon

On a recent trip through British Columbia in September 2020 my wife and I came across a very interesting railway bridge at Lytton which is a few kilometres north of the more famous Cisco bridges in the Fraser Canyon. The Cisco bridges get all the glory but the bridge at Lytton which is crossed by the Canadian National Railway mainline has a pedestrian catwalk attached to the north side of the bridge. The bridge is open to the public and is high above the Fraser River just south of the confluence of the Thompson and Fraser Rivers.

My wife and I walked from the east to the west side of the river across the catwalk, much to her consternation. She was a little distressed at looking through the steel grating beneath her feet at the Fraser River which rushes below. The swift-flowing river with its numerous huge swirling eddies can be easily heard. She was even more distressed at me suggesting that it would be fun if a train would cross the bridge while we were on the catwalk, a suggestion I made when we were half-way across!

I found the location quite easily by Googling it. On the map you will see that the parking lot is at the end of River Street. However, at first we drove right past River Street and ended at a dead end because River Street is more akin to a back alley than a typical residential street.

I hope that next time I am in that area I can hang around long enough to see a train pass over the bridge while I am on the catwalk. The railway traffic patterns were rather messed up the day we were there because the day before 20 cars of a potash train had derailed near Hope, BC. As a result, we saw a number of trains along the Fraser River Canyon that day but very few of them were moving.

In the following pictures, you will notice a distinct haze in the air. This is smoke that had blanketed southwest BC and Alberta from the forest fires on the west coast of the US. After having experienced this smoke for the previous five days our eyes were burning and our throats sore from the smoke. Even though we were wearing our COVID-19 masks over our noses and masks everywhere we went that we weren't alone, they were no match for the pervasive smoke. On the ferry ride from Vancouver Island to the mainland, the smoke was so thick that we could see no land for the two-hour sailing.