Tuesday, April 25, 2017

Latest Effort - Werris Creek Platform Starter Bracket Signal

In line with my recent work on brass signals (last post) I have redesigned the Werris Creek platform starter bracket signal and had it printed in brass. This 3D printed signal was received a couple of weeks ago, prior to my last post.

Here are a few photos of the model as it stands today.




I have painted one signal dolly post for the photos in this blog post but I will be stripping the paint off and spraying the whole signal with some self etch black which will prime the brass and be suitable for the black parts. Of course painting white over the black will be interesting as it will have to be done by brush, carefully.

The prototype signal does not have bellcranks to transmit the signal box lever movement via wire to the signal arm and uses wheels instead. I designed the signal to have working wheels (drilled with holes to be a bellcrank) to get the operating rods up to the signal arms however they are just too small and fiddly to fit. In future the wheels will be cast in place (non-turning) and the operating rods will be bent to run behind the wheels.

To get the operating rod movement I used one piece of 0.015: phosphor bronze wire from the below baseboard mechanism to the counterweight lever. I bent it to replicate the operating wire of the real signal and threaded it through the wheel brackets behind the wheels. Check the photos to see what I mean. A loop of 0.010" wire was bent into a U shape and soldered to the post to retain the two operating rods and minimise flexing of the wire.

The brass post is glued to a boss on the top of the White Strong and Flexible, the square base of the post being hollow.

The two round steel dolly posts are 1mm diameter brass tube from Albion Alloys which can be purchased from Hobbyco, Bergs Hobbies, Brunel Hobbies and Frontline Hobbies. The detail parts on the dolly posts are Frosted Ultra Detail parts that slide onto the posts. The dolly posts fit into holes printed in the signal that need to be cleaned out with a 1mm drill.

Some holes need to be drilled with a 0.4mm drill, some cast OK and some don't. A supply of 0.4mm drills would be useful as I find that some drill well and others don't. I think it is how well the point has been ground.

The drills can be found on ebay or a pack of 10 drills can be had for $10 from McJing Tools in Yagoona NSW.

I will be investigating how to do these dolly posts with details attached in printed brass. I have to keep the height below the 100mm maximum build box of the 3D printer, so some more 'hidden' sprues.

This signal is a trial for the steel post bracket signals to go with the round steel post signal now available on my Signals Branch Shop.

Once this signal is done I will return to the Werris Creek station building, at last - again!

If anyone is interested in how my signals go together I will be having a clinic at the Modelling the Railways of NSW Convention at Loftus on 20 May 2017.



Wednesday, April 19, 2017

Brass Signal Update

Since my last post about brass signals I have added the rest of the signal parts to the post and the 23 ft timber post signal and a new 23 ft round steel post signal with parts have passed the technical review by Shapeways and are being printed.

These two signals are now on my Signals Branch shop.

Update: Signals printed and on the way as of today 25 April 2017 and Shapeways Sale information removed from this post as it was over.

Brass 23 ft Round Steel Post Signal with Detail Parts

Brass 23 ft Timber Post Signal with Detail Parts

I have also added NSWR C32 Sand boxes in brass, Frosted Ultra Detail and Frosted Extreme Detail acrylic material. These larger 1907 sand boxes have been designed to replace the smaller sand boxes of the Ixion C32 as outlined in an article by James McInerney in April 2017 Issue 323 of the Australian Model Railway Magazine.
Brass C32 Sandboxes for Ixion C32 - Also available in FUD and FXD
I will expand the range of brass signals as soon as I can.

Of course the appropriate WSF mechanism and a ladder are required for each signal.


Wednesday, April 12, 2017

A Couple of Things I have been Battling Against

OK, the title is just to catch your eye, no life dramas.

Firstly, I have been working with a Shapeways Service Team member over the brass signal situation and after about a dozen or so emails back and forth and a few more designs it looks like I have made a breakthrough. There is a trial brass signal currently on its way from New York. There are actually four of the same design coming, three for a friend who helped out as I wanted to test the print success rate and one for me.

The breakthrough came when I removed the rectangular base from the brass signal design. I finally worked out that the Shapeways production team for brass don't really like the designer to have sprues as a badly placed sprue to a part can cause the process to fail.

So the signal will comprise a brass post with platform, lamp, signal arm pivot, counterweight lever pivot and a counterweight lever attached by a very short sprue to a small square flange near the base of the post. This flange retains the post when it is pushed into the White Strong and Flexible mechanism that just happens to also have a rectangular base for mounting.

Unfortunately I wasn't able to include the signal arm, cast iron ladder base, lamp top and signal arm rear blind.The good thing is that the counterweight lever is brass so it will be stronger than the Frosted Ultra Detail (FUD) acrylic version although

These extra detail parts will have to be ordered in FUD from the existing range of FUD parts. One advantage of this is that the appropriate signal arm can be chosen whereas if it is in brass I would have to decide which arm to include on the brass signal.

A ladder will be needed and I have a sprue of two (without cast iron ladder bases) or a sprue of ten ladders with the cast iron bases. Of course an etched brass ladder can be used instead.

So the brass signal got cheaper without the rectangular base but the addition of the FUD parts took the price back up to about the same price as an all brass signal post and parts.

Here are some computer renders of the various items:

HO Scale 23 Foot Brass Signal Post
WSF Brass Base and Signal Mechanism
HO FUD 2 x 36 inch Signal Arms and Detail Parts
HO FUD 2 x Ladders (No Cast Iron Base)
HO FUD 10 x Ladders with Cast Iron Bases

The signal and others will be available once I make the coming signal, I will announce this at the appropriate time.

I will be doing a demo/clinic about making my signals, etc. at the coming Modelling the Railways of NSW Convention at Loftus on Saturday 20 May 2017.


Short Circuit!

The second thing I have been struggling with is a short circuit in my layout that seemed to start at the time of the 40 degree Centigrade days here in Sydney a month or so ago.

I did all the usual things such as looking for rails that had closed up around points, etc. to no avail. I then began disconnecting the DCC track bus wiring to various parts of the layout, still no luck.

Part of the problem was that I was supposed to have two track power districts but didn't! I had a sneak path between the districts that was confusing things. After a few weeks I eventually found the sneak path which was up behind the fascia at Coxs Gap at the dividing point of the two 'districts', it was some original wiring that went from one end of Coxs Gap loop to the other.

After many discussions with Marcus Ammann I tracked the problem down to one section but the short had degraded to a power drain and has now become intermittent.

I now have three power districts with NCE EB1 circuit breakers on each district and the problem is restricted to one of the districts.

The layout was turned on for most of today without any issues.

Now I wait and see if it will raise its ugly head again.