Thursday, July 3, 2014

More 3D Printing and a Bit of Video Fun

Today my wife Chris and I finished painting a second bedroom for our two grandsons (7 and almost 5) who have come to live with us with their mother, our first daughter. Their father has decided that he on longer wants to be married and we have been dealing with this since the start of March. This is the reason for the scarcity of blog posts.

Anyway, on with the post but a bit of a story first.

I have been working on a couple of 48 class diesels which started life as Trax 48s but which now have some 3D printed chassis. This is a rebuild along the same lines as the article I did in the April 2001 issue of the Australian Model Railway Magazine (no. 227). In the article I had used layered printed circuit board for a chassis and some Austrains 421 bogies that were purchased at the time (sold as spares).

Now time moves on and my recent foray into 3d printing headed me into the realm of chassis construction. The chassis are printed in steel, yes steel, actually 70% stainless steel with 30% bronze.

How do they do that you say?

Well, a fine layer of stainless steel powder is laid down and resin is printed onto it followed by some heat I think to set the resin then another layer of powder and resin, etc. until the item is finished. At this stage the item is very fragile and it then has bronze infused into it, presumably in a molten state which burns out the resin replacing it in the process.

I had them printed by Shapeways the same company as the Werris Creek station building windows and doors of the last post and I chose a matt black finish which was more of a dark brown as it would save me painting them.

The finish is slightly rough, perhaps like about a 150 grade wet and dry paper. Because of the finish the socket for the half ball pivot on the bogies needed to be cleaned up which I did by using a new drill larger than the hole and by twisting it by hand. The result was a small chamfered edge on the lip of the hole that I had worked out that the ball would sit nicely in.

Unfortunately I didn't take any photos of the chassis before installing them into the two 48 class locomotives. I did take a chassis along to the Modelling the Railways of NSW Convention a few weeks ago and showed them to Keiran Ryan and Phil Badger. They were both very interested.

One slight downside is that the chassis were not cheap being US$51.92 each but they certainly save a lot of work.

Here is a screen shot of the chassis as a 3D model which was designed to use the fuel tank cut from the Trax chassis but including the part of the chassis above the tank. That Trax metal is horrible stuff to cut.

I have since done a second version so that I could use a couple of 48 class fuel tank castings I had purchased from Kerroby which appear to have been cut away from the Trax chassis.

You see I still have two more 48s to add to the roster.

This chassis with the extra block in the centre costs more at US$65.79. it might have been cheaper to cut the fuel tanks off the old Trax chassis but I had purchased the Kerroby fuel tanks several years ago and thought I may as well use them.

These 48s will  be detailed up when I get my two Trainorama 48s, hopefully late this year (or early next year - no I don't know anything about delivery dates).

Anyway back to the video fun, here is a short video I took of the two 48s on an Up Goods dropping down grade between Wollar and Bylong. The sound is actually from the locos which have Soundtraxx Tsunami Alco 250 v12 decoders but I have enhanced it with an equaliser in my video program. I think it sounds pretty good, pity we can't get big speakers into our locos. The 48s only have 13mm speakers as they are the only ones I could fit and also to give a 'smaller' sound to sound more like the 6 cylinder diesel the 48s had.

Wednesday, June 18, 2014

A Bit of 3D Fun

For many years I have been aware of the potential for 3D printing in the hobby. Way back in about the late 1980's or early 1990's Graeme Brown sent me a photocopy of an article on photolithography for 3D printing, I was immediately amazed at the possibilities however this was the really early days of the technology.

Time has passed and we are now in the dawn of a new age with the commercial availability of 3D printing for the masses.

I have been watching this process for the last five years or so and I decided recently that it was time I had a go.

The reason for this was that I had told Ron Cunningham that I would build a model of the Werris Creek station building for his Werris Creek layout. Well, I had visited the station but hadn't truly understood the enormity of what I was taking on. Several visits and a number of years later I had realised that 3D printing was perhaps one of the only ways to get what I wanted. I looked at making masters of the windows, doors and various other items and trim in polystyrene for masters to be used for casting but I couldn't bring myself to start. The problem was that there are four different windows and three different doors on the main building alone. If you also look at the refreshment room/railway hotel building adjacent to the main two storey building you will see that although the doors and windows of the refreshment rooms look similar at first glance they certainly aren't, so more masters to be made.

Here are a few photos of the buildings.

The above photos are of the current paint scheme. 

This photo is of the older paint scheme which the model will likely be done as.
It was time to learn how to draw in 3D on the computer. Now I have done some 2D CAD building/home extension plans but 3D is totally different and requires a new mindset and techniques. 3D models are drawn by using primitives (squares, rectangles, circles, cones, etc.) and then extruding them and removing parts as well.

I have been using Sketchup 14 a free 3D drawing program. There is a professional version of the program but it is US$595 so the free one will have to suffice.

I decided to use a company called Shapeways for the 3D printing and I also investigated another company called iMaterialise but they were more expensive. I think that iMaterialise may give a better print from my research but I needed to keep it cheap as I was just learning.

After about a week of tearing my hair out I managed to produce my first 3D window for the Werris Creek station. At this point I was able to upload my 3D file and the Shapeways web site immediately checked the file for printability. Needless to say it failed, by version eleven I had a printable file.

I then spent more time drawing the rest of the windows and doors.

Finally, taking my wallet out, I ordered one of each window and door in a material called Fine Ultra Detail which is a translucent resin plastic. The 3D printer uses ultraviolet light to change a layer of liquid resin to a hard plastic; the image being a 'slice' of the 3D model. The next 'slice' is projected onto the resin and so it goes. This material is not cheap and each door and window cost between US$7 - US$9 each and there are many of each door and window type in the building.

After about two weeks I received word that the prints had been despatched by UPS and that they would arrive by the end of the day on a certain date in about ten days time.

Waiting, waiting, waiting, I am sure that Chris was tired of me checking for the delivery as it neared the due day. Anyway it arrived on time and I was really pleased with the prints. The prints were each packed in a zip lock plastic bag inside the bubble wrap of the sturdy cardboard box. I found that although they had been washed there was still some resin on them so I cleaned them with some enamel thinners after some research on the Shapeways site.

By now I am sure you are wanting to see the results so here are several of the unpainted windows and doors in a mock up piece of the wall of the station building.

I have just sent off another order for trial prints of a window and door as well as an awning post and a few other trim pieces in a cheaper material called White Strong and Flexible which is actually a nylon, now to wait, again. The nylon shouldn't be an issue with paint or glue as it has a fine dotted texture from the printing process which should give plenty of 'key' to the paint and glue.

Incidentally, as far as I know the window and door styles at Werris Creek are not used anywhere else on the NSWGR.

Now don't go waiting for further exciting instalments of this build, it has already taken about six years to get this far. I will give some updates along the way though.

Wednesday, May 14, 2014

A little bit of recycling

I was given a Weber Kettle Barbeque just before Christmas last year and when I was cleaning it out after the first use I noticed something interesting.

The ash from the coal briquettes was a nice light tan colour, now that has some potential I thought.

So out with a fine sieve and after sieving out the clinker I was left with something that could be useful as soil on the layout. I had an old 300um (.3mm) sieve from the laboratory I used to work in but I have seen reasonably fine sieves in the kitchen equipment section of shops. The ash didn't need any crushing I just sieved it as is.

I applied it to some areas around the Cassilis turntable where I wasn't happy with the soil colour. I used the Long Life Self Shining Floor Polish (actually a clear acrylic coating) as usual to glue it in place and the colour came out darker once dry but still acceptable. The soil has been down now since earlier in the year without any apparent negative effect given the unknown chemical nature of the ash.

Here is a photo of the result:

So now, who has a kettle barbeque?

Saturday, May 3, 2014

Mowing grass, beaten to the punch

I have been going to do a post on 'mowing' static grass for a while but Rod Kelly has beaten me to it in his latest blog post. Great minds think alike  ;-)

A couple of years ago I tried to 'mow' the static grass with an old hair trimmer that my daughter who has a hairdressing salon no longer used. It worked OK but didn't keep its charge for long, the rechargeable batteries being at the end of their life.

Recently while going through some things that my other daughter had left here when she moved out, I found a lint shaver (used for shaving those small balls of lint from clothing).

Of course I knew that this was a potential replacement as long as it could cut the static grass.

It works really well, runs on a couple of AA batteries and is also cheap to buy, I can't give you a price but I know that I have seen them in Woolworths.

The static grass when applied is all the same height and uniformly spread which looks wrong. To glue the grass I use Long Life Self Shining Floor Polish (actually a clear acrylic coating) applied to the soil surface immediately before applying the static grass. This only gives a slight bonding and the grass can be knocked over or removed by rubbing. I then use the lint shaver which tends to remove the grass from the soil if the blade is run along the surface of the soil or trims the grass to length if held above the surface. I follow this up with another spray of the Long Life Self Shining Floor Polish (available at Woolworths and Bunnings) but this time I add about 10% methylated spirits to help wet the surface and grass so that the acrylic doesn't just attach itself to the tops of the grass in little droplets.

Here are a few photos of mown grass. You can see where the grass has been removed and also trimmed in height for a much more realistic effect.

Sunday, April 6, 2014

Accessing the gears in a Trainorama NSWGR 44 Class bogie

Trainorama have said that they are bringing in replacement axle centres for their NSWGR 44 class bogies that seem to suffer from split gears.

If you have tried to get a 44 class bogie apart then you will know that it is almost impossible. It seems to have been designed to go together and not come apart.

The problem is that there are eight small clips that hold the bottom plate in place. The clips are on the bogie gear box sides and they clip onto the bogie bottom cover plate, however the clips are in a small hole and are almost inaccessible.

The solution to getting the bottom plate off is to grind the clips down until there is only a small amount of plastic still holding on. At this point the cover plate can be removed by flexing the two ends upwards while using your thumb to hold down the centre of the cover plate. This is harder to explain than to do.

I used a micro-engraver which I got from Jaycar but I have seen it in other places such as Bunnings (some time ago). The advantage of using this engraver over a larger Dremel style hand tool is that this engraver is battery powered and doesn't have much torque, there is no out of control damage when the bit digs in, the engraver just stops. A good magnifying light is very useful as well.

Here is a photo of the engraver and the Jaycar link.

You will need to use a small bit in the engraver.

Here is a photo that shows the clips already ground down, I apologise that it is difficult to see the ground down clips in the four square holes along each side of the bogie cover plate, I tried to get a good photo but black plastic clips in black plastic holes are not easy to see at any time.

Now we wait for Trainorama to bring in the replacements.

Tuesday, March 11, 2014

Prototype correctness or 'artistic' effect?

I have an interesting 'issue' on my Bylong layout involving the placement of the NSWGR trackside line poles.

Now, on the prototype the line poles are placed on the left hand side of the line when leaving Sydney however I have placed them on either side of the line due to space constraints and sometimes because they look better when placed on the wrong side of the track. This has been brought to my attention several times but I have resisted correcting their placement.

Sometimes the poles are placed so that they do not throw a shadow on the backscene and this can put them on the wrong side but then there are other places where I have purposely placed them incorrectly.

I have to say that I like to see the trains in the scenery and not running in front of it and this extends to the line poles if it suits the scene.

I haven't done a search of photos to determine if the line poles were sometimes located on the right hand side of the track when leaving Sydney so I don't know if this ever happened. It can be a problem when viewing photos to know if a train is an UP or DOWN train which of course would be necessary to see which side of the track the line poles are located.

Well I like the layout as it is so I probably won't change anything.

Here are two videos, the first shows the poles on the wrong side and the second on the correct side.


Wednesday, March 5, 2014

New Outer Teardrop Scene

The expanded foam eruption ended and I was able to start repairing the damage to and around the road bridge which I could have done without.

I then applied pre-mixed cornice cement to fill in any gaps between the foam pieces and to generally smooth things out. I then used some dry powder colour and a wet brush to apply a basic brown to the surface of the plaster to minimise the potential for any white to show through the scenery later.

After this I marked out the lineside fence post positions on the balsa and the foam, made the holes and put a toothpick into each hole. The reason for this was so that I could find the post holes after I had applied soil and then static grass, it worked quite well apart from the toothpicks getting in the way of the static grass machine.

I used fine sieved soil to cover the whole area and applied a slightly different colour in several places.

This was then sprayed with a methylated spirits and water mixture to allow the 'Long Life Self Shining Floor Polish' (an acrylic clear, available in Woolworths - 500ml or Bunnings - up to 5 litres) to easily saturate the soil. The 'floor polish' sometimes needs to be done two or three times to thoroughly bond the soil but I usually try it and only add more later in any problem areas. I think the trick is not to apply too much methylated/water mixture.

While the soil was wet I applied various colour static grasses, looking for a dry grass effect with a little greener grass in some low lying spots. I also applied some dark green flock to replicate some blackberry or similar low bushes. It was interesting trying to match in with the thirty year old scenery in the centre of the teardrop. I still have to add some dry static grass on the track side of the inner fence to help tie it together. Also the old fence droppers made out of thicker wire will have to be replaced with the new thinner ones.

Here is a picture of the scenery after this first effort, grass tufts and more shrubs and foliage to be added.

And here are a few photos of the first train through the scene.