Electronics, signalsPosted by lennart Fri, July 29, 2011 14:11:50
As some of you might remember (see this earlier post) I had the intention to fit a Digitrax SDN144PS sound decoder in an Atlas GP-40 engine. At that time I had no idea how I should manage to fit all the stuff (decoder, speaker and capacitor) into the engine. And I am still not sure if I will manage. Anyway, I thought I should update you regarding the status so far.
I soon figured out that the only place for the speaker would be in the fuel tank, facing downwards. A bit of the frame would have to go, to make room for it. I also decided to skip any ideas about a speaker casing. No space for that and me, with no previous experience of sound decoders, not knowing what would be required to make a casing worth while.
So I disassembled the locomotive and started to grind away at the frame, using my Dremel motor tool. The speed (RPM) regulator of the tool broke when I was halfway done so I did the last part using a Dremel bit in my drilling machine. Not very effective, but eventually I was done (I really need to get my self a new Dremel). Here is a shot showing the "hole" where the speaker will sit.
Not the neatest of milling jobs, but hopefully it will serve its purpose. I also made a hole in the fuel tank. I did not only drill a set of small holes for the sound to get out, but a large hole, the diameter of the speaker, so that the speaker fits inside the hole rather than behind it. In this way I gained the thickness of the fuel tank material and did not need to remove as much of the frame (hole not as deep as otherwise required). Here is the hole in the fuel tank.
Below is a picture showing how the speaker will sit in the fuel tank, flush with the bottom of the tank.
Last I made a groove in one of the frame halves, for the speaker wires. I also removed part of the frame at the very top. This to make room for the decoder.
The wire groove is the diagonal cut above the place where the rear truck goes. You might also notice that the top of the facing frame half is a little shorter than the other one (to the right of the text "Atlas"). I still need to do the same cut on the other frame half.
Electronics, signalsPosted by lennart Mon, April 25, 2011 21:20:36
The signals at the other end of the siding, outside tunnel 16, are in place. As at the opposite end I had some clearance problems with the signal between the tracks (this time the dwarf), which forced me to place the signal farther way from the turnout than I had wanted. But it's OK. No big deal. Here are some photos.
I have also strung some sewing thread between the telegraph poles. The idea was that it should pass as electrical cabling. I am not sure whether I like the result or not. I had to tighten the thread or it would curl in an unrealistic way. But now it looks to tight I think. Real wire sags a little under its own weight which mine does not. For the time being I will let it remain.
Last, here is a photo of two new cars - two PS-4000 Covered hoppers from BLMA Models. Really nice models with metal wheel sets, body mounted couplers and see-through etched metal roof walks. Click on it to see a larger version at higher resolution.
SceneryPosted by lennart Sun, April 10, 2011 17:07:19
I did some detailing today, installing a few trackside electrical boxes. I used a kit from BLMA containing two etched metal electrical boxes.
I also reused another, somewhat larger, box from the previous layout. I assembled the BLMA boxes using CA and some Kristal Klear, and removed the painting from the old one. That one was already mounted on a concrete slab made from plaster, but the other two got new styrene foundations.
Then I painted all three of them using a light gray paint. The styrene foundations got some tan color as well. Here is one of the smaller boxes installed on the layout.
A view from above tunnel #15 showing the larger box as well.
Electronics, signalsPosted by lennart Sat, April 09, 2011 16:12:36
Today I placed the first signal on the layout and test lit it. Here is a train waiting for the signal to clear.
The clearance is a little tight. When laying the track I did not give enough thought to the fact that I needed space between the tracks for a signal. But it works even if it is a close fit when the hi-cubes pass, leaning inwards on the super-elevated curve.
The prototype avoids a similar problem by letting the siding curve around the signal as seen here - or perhaps there is another reason why the track curves as it does.
The signal remains to be bonded to the ground, and the electrical connections are still only temporary with the signal under total manual control (terminal strip and screw driver). I have not yet decided how to control the signals, so this was a quick fix just because I was eager to se the signals in place and lit. In the next picture I have managed to make the signal turn green.
Last is a side shot of the signal. This picture also gives a nice view of the rail size difference between the main line (code 55) and the siding (code 40), especially if you click on it to get a larger picture.
SceneryPosted by lennart Thu, March 24, 2011 20:47:25
The ground cover is in place, everywhere! To top things off I also added some telegraph poles. These are poles I salvaged from earlier layouts, both from my old Tap Creek layout and the previous incarnation of the Tehachapi.
The old poles had varying number of cross-arms - some had four, some had three and some had two. On this layout I wanted all of them to have the same number of cross-arms, since they will all be along the same stretch of track. I settled for two arms on each pole, as in the banner photo on the top of this page. So I removed some arms from some of the poles, and mounted them on some new poles instead, ending up with a fair amount of two-arm poles.
Here are some photos. Click on a photo to see a larger version.