Wednesday, August 26, 2015

A Paddock Full of Sheep

Over the last few months I have been trying to distract myself from events earlier this year and have done a few different 3D printing projects. Two of these are HO sheep both in 'free range' and wagon loads.

Both the free range sheep and the wagon loads can be seen in this photo of 5085 climbing the grade to Wollar with a stock train of sheep.

Those who know the layout will note that the stock train is headed towards the country, away from the Bylong abattoir and the city abattoirs so the sheep must be being moved for agistment elsewhere, 1965 being a year of drought (yes, I know my backscenes are too green for a drought).

The sheep wagon loads have been designed to fit both the Austrains NSWGR GSV four wheel sheep wagon and the Eureka Models BSV bogie sheep wagon.

I have now offered them for sale on my Signals Branch Shapeways shop and while the price may appear to be of some concern the quality can be seen in the above photo and the 64 'free range' sheep work out at 57 cents each which is a bit over half the hobby shop retail price of approximately AU$1. The wagon load sprue has 100 sheep so these work out at 37 cents each.

The roofs of the above mentioned sheep wagons come off by slightly levering at the roof corner. The GSV floor comes out by slightly flexing the lower body sides away from the solebar. The BSV bogie wagon floor comes out by first pulling the buffer heads out of the wagon and then slightly flexing the lower body sides away from the floor.

It is advisable to spray the sheep on the sprue prior to snipping them off as it is easier to touch up the white snip area than to hold and paint the sheep individually. For Australia, a light brown is more correct (dust) than white as would be found in England or Europe.

While these sheep a just standing I hope to modify them so that they are grazing or looking another way, etc.

I hope that the modeller will find these useful.

Clarification of Sheep Wagon Loads:

1 sprue of 100 sheep has 4 blocks of 25 sheep which will do 2 GSV four wheel sheep wagons or 1 BSV bogie sheep wagon. The legs are dangling free so to speak, no 'floor' on the block of sheep.

Tuesday, August 25, 2015

Shapeways Free Shipping until 30 August 2015

In case anyone is interested, Shapeways, the 3D printing company that I have my Signals Branch shop with is offering free international shipping if you order more than US$35 worth of prints before 30 August.

Of course you can also go to the miniatures, train models categories in the general shop section and check for anything interesting there as well.
Shapeways normal shipping rate is US$15 which is about AU$21.

Monday, August 17, 2015

Signal Box Rebuild Update

Well, I have slowly been working on the signal box modifications and I am reasonably happy with how it is coming along.

I received my Frosted Ultra Detail signal box door to replace the incorrect one and gave it a soak in some acetone for a couple of minutes to remove the remaining light oil that Shapeways use to remove the wax support material.

Unfortunately, you have no control with Shapeways over how the item is oriented in the 3D printer and this can impact on some surfaces leaving white and very slightly rough areas where the wax support material was attached. These areas can often be smoothed with wet ad dry paper or by scrapping with the edge of a hobby knife blade. The orientation may also leave very fine print layer lines and this was the case on the rear of the door. Most of the back of the door didn't matter except for the glass areas. I used a small 3mm wide chisel blade that I had ground from a small wood carving chisel many years ago to scrape the rear glass smooth. I then gave the glass areas a coat of clear gloss acrylic paint front and back which made it go almost fully clear, clear enough anyway to look right.

I have added the missing small vertical trim pieces on the gable end walls and used some 12mm wide modellers masking tape to mask the windows prior to spraying the Light Stone (it was exactly the right width).

I then added barge boards, fascia boards and gutters as well as spraying the walls Light Stone. I used Humbrol Matt 103 a cream to represent the Light Stone. It is slightly yellow but could be toned down with some weathering. The door was painted white as a bit of research indicated that the signal boxes didn't always seem to follow the usual stone colour schemes and often had very simple schemes. It seemed to be a bit hit and miss. The doors colours varied, sometimes all Dark Stone, sometimes Dark Stone with Mid Stone lower panel and with or without the white window trim. Later signal boxes in the pastel colour era seemed to often have a white door so I decide that this signal box was part way into that simplified scheme era.

Here is the current state with Dark Stone gutter and trim colour added. I haven't decided if I will do the vertical trim on the gable ends with the Dark Stone or not (veering towards not). Still thinking about adding some Mid Stone on the gable barge boards.

One thing I like about 3D printing is the ability to add small details such as the door handle and the bolt on the signal box door. The door handle is actually a proper knob with a thinner shank behind.

Of course there are the limitations of the 3D printing design minimums to be taken into account when drawing anything up. I should probably mention to anyone thinking about getting into 3D printing to be careful with your design as the various 3D printing companies don't use the same design minimums (usually related to wall and 'wire' thickness minimums). The prices vary considerably as well. To me Shapeways is the cheapest at the moment but there is the orientation trade off and their minimums are smaller so there can be a potential for breakage of very thin parts.

The small platforms outside the door and across the tracks are next on the list to be done.

Monday, August 10, 2015

Catch Point and Indicator

For some time I have been aware that I should have catch points on my layout but after looking at a number of station track plans I am not sure what the rules are for placement. They seem to be protecting sidings onto the main which is obvious (e.g. private sidings, oil/petrol sidings, etc.) and also loops but then not all loops.

Since the station yards are already in place on my layout I have decided to install a few where I have the room for them.

On the layout I have used code 70 track and points from Shinohara, Peco code 75 track and points, Micro Engineering code 70 track and a number of code 70 hand built points so I began by looking at the Peco code 75 catch points as these were the only commercially available ones I knew of.

A study of a NSWGR Standard Catch Point plan from 1936 showed that the Peco one was reasonable but not quite right.

Here is the 1936 plan:

I decided to try to draw up a 1936 catch point for 3D printing. Once again I used Sketchup a free 3D drawing program (there is also a professional version that is about US$500).

Here is a screen view of the resulting 3D model; I have done both a left and right version. The horizontal pieces are two sleeper variations that plug into the two long sleepers at the left hand end and are for mounting the catch point indicator. The small triangular piece is the hardwood block that guides the wheels up and over the rail (see plan above) and it plugs into the sleeper with the small square hole in it.

The catch point has been designed to take code 70 or code 75 rail (as long as I have measured and drawn it correctly). Of course a single point blade will have to be filed up and it would be pivoted on a fish plate. Due to the minimum wall thickness restriction of the 3D printing process for the White Strong and Flexible material the tops of the dog spikes may need to be filed slightly once the rail is in place to clear the flanges (based on flanges to NMRA RP25). Being a nylon the webs between the sleepers may be cut occasionally (every alternate web) to enable a slightly curved catch point to be made.

I haven't had one printed as yet but will probably do so soon as I will need to check that it all works before I make it available on my Signals Branch Shapeways Shop.

One reason for delaying is that I am drawing up a catch point indicator which I would like to make work off the catch point blade. The basic shape has been done but I am a bit stumped at the moment on trying to work out how to get the indicator part to rotate through 90 degrees with only a very small movement from the point blade. I guess if I can't get it to work then I will release a static version.

Catch Point Indicator at Gunning - Sourced from the Internet, Photographer unknown
The indicator will be printed in the Frosted Ultra Detail material, a translucent plastic that can be used to pipe some LED light for the aspects from below the baseboard.

You would think that this would be easy since I have an actual catch point indicator in my layout room, a 50th birthday present from my brother Noel (it came from the Tumut line - he used to live at Adelong). Unfortunately what works on the prototype may not work on a model.

I am not sure how many modellers would be interested in a lit and working catch point indicator but there is nothing like a challenge!

Monday, July 27, 2015

SDS Models Bitumen Tanker - Fixing the Handrails

The SDS Models Bitumen Tanker is a lovely model however it has a small issue with the handrails on the walkway. The handrail posts directly above the ladders on each side do not touch the walkway, they are between 0.5 to 1mm off the walkway. This appears to have been caused by the handrail post mounting holes in the tank not being drilled or moulded deep enough to allow the handrail posts above the ladders to drop down to meet the walkway.

I decided that this needed to be corrected so I used a pair of long nosed pliers and a piece of strip wood as a levering block on the tank to carefully extract the vertical handrail posts from the tank one at a time. The posts do seem to be glued but it is a flexible type possibly an acrylic contact cement and the posts came away easily on my model.

Once all the posts were out I cleaned away any excess glue from the tank and posts ends. I then drilled the mounting holes in the tank deeper using a 0.7mm drill in a pin vice. The tank casting drills easily.

The tricky process of getting all the handrail posts back into the tank mounting holes came next. It isn't to hard, just take your time and dry fit the posts working from one end of the tank to the other. I followed up by applying a small amount of clear drying acrylic contact cement to each post mounting point with a pointed tooth pick.

Unfortunately I didn't take a before photo of the handrail post issue but here is a photo of the finished tanker, still to be weathered.

As can be seen from the photo bitumen tanker is the one with the flues on each end. The flues were there as these tankers had gas burners running through the tank which allowed the bitumen to be reheated if it had cooled enough so that it would not come out of the tank easily. I chose this version of the bitumen tankers as being fitted with the flues and burners it could be left in a goods siding to await the arrival of a Department of Main Roads NSW spray seal truck which could use its own gas tanks to reheat the bitumen if necessary. So this is the version tanker that can be useful on the pickup goods during operation sessions on the layout. The other version bitumen tanker does not have the flues and burners so would be for delivering the bitumen to the several BORAL depots around the state. A spray seal truck is used to spray molten bitumen onto a prepared road surface which is then followed by a specially fitted tip truck that spreads a single stone thick layer of stones onto the bitumen by reversing over the freshly spread stones. This process is then followed up by a roller that embeds the stone into the bitumen . The rolling must be done quickly as while a stone will push into bitumen that has cooled it ultimately come out of the surface by the action of the traffic.

Of course,wanting this particular tanker meant that I had to buy the two pack with the blue AMPOL heavy oil tanker which I didn't particularly want as I never saw them in blue. I am going to heavily weather the blue tanker so that it is virtually black as by 1965 they almost certainly would have been, having been painted blue in the 1950s.

Now, do I need an oil burning D55 or D59 Class and a heavy oil filling point in my Wollar locomotive depot?

Saturday, July 18, 2015

New Air Compressor and Two Dual Action Air Brushes

This morning took a risk and bought a small air compressor that came with two dual action air brushes at ALDI for $99.99.

Here is the product description from the web site:

Product Description
  • Ideal for tattoos, nail art, makeup, artwork and modellers
  • Airflow:20-23L/min
  • With variable pressure gauge
  • Compact and light weight design
Air Brush Kit:
  • 1/6hp compressor
  • Low noise: 47db
  • Speed: 1450/min.
  • Airflow: 20-23L/min.
  • Variable pressure: 3 bar/57psi
  • Standard 1/8" BSP fitting
  • 1.8m braided hose
  • Includes 2 dual action air brushes
  • Oil free pistons
  • Auto start/stop feature
  • Adjustable pressure with gauge (on/off light)
  • Filter and thermal protector

I haven't included the web page address as it will likely disappear shortly.

This air compressor and air brush package became available this morning (Saturday, 18 July 2015) at ALDI stores in NSW, and maybe all stores in Australia.

I have tested them and I am quite happy with both the air compressor and the two dual action air brushes.

The air compressor is very quiet when running and does not pulse the air as it seems to have a small reservoir inside it. It will take the air pressure up to 57 p.s.i. then cut off until the pressure drops to 43.5 p.s.i. then start up again, which is almost straight away once you start to use an air brush. I set the compressor output to 25 p.s.i. and it sprayed well.

The two air brushes are different, one has a bottle attachment and a small cup which are friction fit. I found that the small metal cup was a problem when I tried to spray the sides of some rail as the paint leaked over the top of the cup due to the angle I had to hold the air brush at. The bottle of course would not suffer from this restriction. So the cup will only be useful for spraying with the air brush held horizontal. Also the hole in the metal cup where the paint is drawn into the air brush is not smooth and rough edges can catch small pieces of tissue when cleaning which may go through and block the air brush. I will attempt to use a motor tool with a small stone to smooth this down but I really can't see any real use for this metal cup anyway.

The second air brush has a screw on metal gravity cup that can be set at any angle so that spraying rail is easily done by adjusting the metal cup so that it remains relatively level. The cup has a press fit metal lid with a small hole so even if you do angle the brush too far it won't be too much of a problem.

I have a large compressor with a 50 litre tank but it doesn't easily allow me to move around the layout to spray things such as scenery and track so this little air compressor is just the thing I needed.

If you haven't tried dual action air brushes then this a good opportunity to give them a go without spending very much money.

I have previously bought a dual action air brush from Super Cheap Auto for $48 so this compressor and two dual action air brushes is a very good deal.

Usual disclaimer, no I don't have anything to do with ALDI other than being an occasional customer.

Wednesday, July 1, 2015

Modifying a Southern Rail Signal Box

At the recent Epping Model Railway Club 'Brickpit' Exhibition I picked up a Southern Rail Signal Box as it looked quite nice.

Now, before I got it I knew about the incorrect style of door and had some thoughts about changing that if it was possible. Of course the signal box may have been modelled after one with a different door to the standard one so perhaps it may not actually be incorrect.

I also knew that the barge boards under the gable ends of the roof were incorrect as they should be one the very end of the roof and this was definitely a mistake (see photos below).

Unfortunately, what I discovered once I had a chance to sit down and examine it closely was that the model walls were made up of  16 'concrete' panels but the original concrete signal boxes of this type had only 12 panels. Nothing can be done about this so it will be what it is.

Southern Rail photo - Lamps shown are not the production ones - Red text by RP
Here are three photos from Branchline Modeller No.3 to show what the signal box should look like.

Berrima Signal Box showing door and 12 x 10" panels in wall - R. Taaffe 1981
Mindaribba Signal Box showing door and panels
Coolamon Signal Box with 15" panels and the correct style door.
Overall though, I felt that it can still make up into a nice signal box.

I began by cutting the glue holding the small platform to the signal box to give me access to the door. I did the same to the glue holding the bottom of the platform legs, stairs and handrail posts to the base. I found that the handrail posts at the stair end were too long and were tipping the platform away from level so I trimmed the bottoms of the posts with a pair of transistor nippers.

I then proceeded to cut the barge boards away by scribing at the intersection/corner against the underside of the roof with an XACTO blade but using the back edge of the blade tip, I hope that this makes sense.

Once the barge boards were removed I was able to see that I could use the XACTO blade to carefully slice away the glue holding the roof on. The glue appears to be a water based contact cement type and will come away with a bit of work.

Once I could see inside the building I found that the door was part of the wall moulding. I used a fine circular saw blade in a motor tool running slowly to cut through each side of the door and then finished off the remaining corners scribing with the XACTO blade. It was a very nerve wracking job. It would be possible to do this just by scribing with the XACTO blade but it will be slow.

Signal Box waiting for the correct door, LEDs and paint
Now for the door which has four glass panes in the top section and a bit of panelling below. I did a search of available suitable doors such as those produced by Grandt Line and Tichy Train Group but came up empty.

Nothing for it but to design one and 3D print it so I spent an hour or so and came up with the one in the picture below.

Door with handle and bolt as per photos - The long tab on left side is to locate the door in the wall
I have yet to order the door but it will be printed at Shapeways in Frosted Ultra Detail as the frosted material will go clear if coated with some clear lacquer (window panes).

I intend to repaint the signal box in the stone colours and to add some small SMD LEDs to the lamps and inside the box. The lamps need to have the underside and each edge/corner painted black (see the lamp on the wall of the Mindaribba Signal Box in the photo above).

Well that's where it sits for now, I will report back when it is further down the track.