Diamond Ho!

This weekend I kept up the momentum created by getting the first turnout servo installed and started in on the only bit of Comstock Road’s trackwork that requires hand made frogs, the diamond crossing. Through the miracle of Templot, the diamond is asymmetrical with one leg being on a transition curve. Not something you are going to get off the shelf but a feature that let me squeeze things in the way I wanted. Now I just have to build it.

I started by re-reading the relevant sections of Trackwork Handbook for Model Railroaders by Paul Mallery since I have never built a diamond and haven’t built a turnout frog a very long time and not many of them then. Including the diamond in the trackplan was a deliberate creation of an opportunity to do something a bit challenging.

I printed off a copy of the crossing template, found a suitable bit of pine 1×4 and my file and dove in. Much bending, filing and fitting later, I was ready to apply some solder.firstfrog.jpg

Once I figured out that my piddling little 80W digital iron wasn’t going to cut it, I broke out the big 120W Weller and things started flowing. I soldered things into a blob and then spent more time than I like cleaning it up. Nevertheless, a result was achieved that compared well with the paper version.templatevsreality.jpg

The second frog aka V-crossing went considerably faster as I applied my learning from the first one. It was necessary to redraw the reference lines before I started since the wood block got a little singed.secondfrog.jpg

At the end of the evening, I have both V-crossings built and am looking forward to doing the K-crossings. I have not applied any detailing to the frogs and may not do so prior to installation. I will probably regret this decision. Here are both pieces posed in situ on the layout.vcrossings.jpg

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Weekend Reading: Trackwork Handbook for Model Railroaders by Paul Mallery

trackworkhandbook.jpg

This the book I was re-reading this weekend to brush up before starting in on the diamond crossing for Comstock Road. I have had this book for many years and actually did a search of my previous postings because it seemed strange that I had not already done a post on this book.

This classic is THE book for those intending to hand lay model railroad track in the North American tradition. It covers all kinds of details of the prototype and then gets down to practical advice for the modeller. Written long before DCC or the advent of the Fast Tracks CNC made jig empire, the methods described are what you need to build any kind of track using flat bottomed rail, spikes and a few simple tools. I needed to re-read parts of it because I haven’t built a turnout frog from scratch in more years than I care to count but the asymmetrical diamond on Comstock Road is just the sort of situation where these methods shine.

Even if you do everything with commercial jigs or castings, I highly recommend this book as a reference for prototype practice and other practical trackwork matters. Published by Carstens, it is currently out of print and not listed on the White River Productions site although several other Carstens books are. It looks like the book stand at train shows is your best bet if you want a copy although you might turn up a reasonably priced copy online. (unlike the unreasonably priced ones I found when I checked while writing this post.)

Turnout Control Progress

I have mentioned previously that getting hand laid points connected up and suitably under control has been a stumbling block in past efforts. The achievable scope of Comstock Road (4 or 5 turnouts total) makes the mental size of the task easier to contemplate. I have begun the new year as I mean to go on, by tackling the mentally hard things and have made further progress.

First up is the connecting rod from switch stand location to throw bar. Increasingly prototypical possibilities have occupied my imagination but when I found myself contemplating scratchbuilding scale clevis’, I realized that I was making things harder than they should be, certainly for a first attempt. I resolved to make something out of the piano wire on hand.

I needed an eye or loop in the wire to connect to the vertical shaft comping up from beneath the layout. (I am going for a rotational motion like a switch stand rather than the model railroady back and forth in a big hole. I fashioned a simple jig consisting of a piece of scrap plywood with a nail driven in and cut off, and adjacent to a piano wire sized hole. A right angle bend near the end of the wire goes into the hole and the wire is wrapped around the nail to form the eye. I got the idea for this jig from the Animated Scale Models Handbook.

Here is the jig.bentwirejig

And here is the result trimmed up.eyeinwire

I have got the vertical brass tube and wire combo installed and connected to the throwbar. (We pause while I dash downstairs to take a photo of the installation which I apparently forgot to do. Lack of photos is usually a good sign since it indicates that I have got a head of steam up.) Here is a shot of the connecting rod installation. Bending the crank in the end of the vertical wire was a challenge and I will consider better alternatives such as soldering on a separate piece of brass bar. It does work and will be concealed by the switch stand. The other reason for a separate bar would be to allow the vertical wire to continue up through the stand so the target can rotate.connectingrod.jpg

Finally, we get to installing the servo, Tam Valley Octopus servo driver and associated electrical bits. I have got as far as fashioning a bracket for the servo using a section of 1/2″ aluminum channel from the big box store. I picked this idea up somewhere in the model railway reaches of the internet and it works a treat. The servo is just a friction fit in the channel after a slight pinch with a pair of pliers.bracketmk1

Beginner Brass Bodging

I have previously mentioned some books on model related metal work by Simon Bolton and Kenneth C. Foran. My soldering and brass shaping skills are rudimentary at best and I did not feel comfortable plunging directly into rolling stock construction so I set out to find a simpler project. While walking past a construction site, I hit upon the answer, a roll off waste bin. These ubiquitous items of the modern era are locally sourced and constructed from metal sheet and structural shapes. Just like those in the metal rack at the hobby shop!

I cast about for a suitable example and discovered that most waste disposal companies provide overall dimensions for their bins as well as photos thereof. Just the thing for the modeler in need. Subject identified, I prepared a basic dimensioned drawing and set about acquiring the necessary brass square tube sizes and sheets.

I made good progress but there was an issue. My Hakko FX888 digital soldering iron is not quite up to the job of soldering a joint where one or both halves is a big sheet of brass aka a heat sink. Cold joints were the order of the day and I put things aside while I mail ordered a big 120 watt iron in hopes of solving that problem.

Today I dusted things off and had a go, big iron and all. The thing is a monster with a half inch tip on it. Not for detail work but boy howdy, does it heat things up. Maybe too much. I managed to avoid desoldering everything previously attached but that wouldn’t be hard to do. Perhaps a finer tip is in order if I can get one.

Anyway, here are the two competing irons, the Hakkohakkoiron.jpg

And the 120 watt Weller old school iron (not so old school as to involve fire but still)bigiron

And here is the project to date. Todays progress was putting the sides, end and bottom together.binprogressjpg

Jeweler Saw Practice

Having just finished the electronic part of installing a DCC decoder in Comstock Road’s lone Atlas O SW-8, I set out to finish the job by making sure everything was correctly insulated, taped down and able to fit inside the diecast metal shell. Perceptive readers might wonder why I mention the shell material. That is part of the fun!

Getting the wires all tucked in was not too much of a challenge but I then discovered that my estimation of clearance between speaker top and shell was, er, optimistic. The issue was the speaker mounting lugs cast into the inside of the shell. They are almost a fit for the chosen TCS speaker but only almost. I have also elected to not attach the speaker to the shell to give more clearance for a future detailed grill.

Here is what the inside looked like when I started.sw8mountlugs

Since the lugs had to go anyway, I resolved to “daylight” the opening back to something akin to the prototype rectangle. This would give plenty of room for the speaker to shoot upwards.

I got out my trusty jeweler’s saw and my excessive supply of #0 blades. Back in the day, I bought a gross of this blade size in a fit of enthusiasm and only afterwards discovered that #0 is too coarse for .015″ material. I have despaired of every finding a use for all those blades but no longer!

Even the relatively heavy #0 blades are fragile and do not tolerate careless use. You can turn corners in a cut but you have to carefully saw in place while rotating cautiously. If you push to hard you can jam the blade and snap it. Letting the work twist on the blade while repositioning can break a blade… You get the idea. Fortunately, I have about 12 dozen blades for just such an emergency. Or I did. I am now better at sawing and have less blades.expendovblades

Eventually, I got the opening cut out to my satisfaction. Here is the view from above with the shell on. (Apologies for the bad focus.)speakerhole

And here is the top view with the stock screens and grills back in place. All being black, the speaker is not visible unless you get up close and look straight.sw8postsurgery

DIY Jumper Wires

Anyone who has ever built a prototype circuit using a breadboard has encountered jumper wires. These wires have connectors on the ends which can fit into the holes on the board as well as the appropriate connectors on circuit boards. There are also male and female connectors (a jumper wire has a 1 wire version of these on each end). These connectors are usually referred to as type JR. You can purchase some premade but if you want anything odd like a 10 wire connector splitting to 6 and 4 connectors, you need to make your own. And of course, there is a crimper for that.

My plan for hooking up the control panel for Comstock Road’s traverser control panel involves the aforementioned split arrangement. This became the pretext to purchase yet another crimping tool along with the appropriate connector kits. And learning began…

I discovered that getting a good crimp was a bit of a challenge and it took a couple of YouTube video watchings and 3 out of 4 pins on the connector botched before I got it sorted. You cannot buy the pins separately so off I went to get another connector. Fortunately, the 4-wire connector is less than a dollar so the tuition is not high. If you get one of these crimpers, buy extra connectors for practice.

Here is the tool and the 4 and 10 pin connectors in progress.jrcrimp

Adhesive Update

I previously mentioned Foam Fusion glue. It works quite well for foam and wood in a tight joint but, being very low viscosity, it does not fill gaps at all. My attempts at “cookie cuttering” foam shapes to fit around the trackbed are not precise enough for Foam Fusion to reliably work for attaching the foam to the wood. Since those joints will not be further shaped by hot wire tool, I realized that I could try something else and save the special glue for joining foam to foam.

The next candidate is polyurethane glue which I learned of from Luke Towan via one of his excellent how-to videos. (I knew of Foam Fusion previously but Luke also provided the impetus to try it as well). Polyurethane glue is a bit more viscous although it is still runny enough to drip down a vertical surface if you pour it on too heavily. It also expands which makes it excellent for filling the gaps between wood and foam. That same expansion property requires clamping unless you are not particular about how much the pieces shift.PEandFF

First attempts with the new adhesive provide very solid joints so will continue to use it for the wood to foam joints. Here is an example of the expansion which came up out of a joint where I dribbled the glue in from the top.peglueexpansion