Yes thanks Keith, gonna leave the sample a few weeks and see just how hard it gets! Testing testing testing! Also applied red mix of acrylic, knowing it is not very matt and needing a sandstone look, I threw a sprinkling of talcum powder on one half! It works beautifully to dull down the sheen of the acrylic and to give that rough surface effect of stone! Result! Still waiting on my texture rollers to turn up so that i can carry on with the stone bridge. I think I have decided that I will use the Faller bridge the the steel mid level bridge, I will use the extra side in the middle and am creating a bespoke base for it! The aluminium has turned up for the stay cable bridge as has my RTV silicon, first cast started tonight! Recently added a few (20+) links to the LINKS page. The garage and all other backlogged workbench projects have stalled, as I get my 'Bridge' on!
Given the Faller bridge is incomplete and not wanting to steal parts from other complete bridges, a nice little test item was devised for my, just arrived, first ever RTV silicon compound. 40 minutes later, I have 9 new bridge bearing plates!
A few interesting revelations occurred tonight. The Green Stuff World textured brick rolling pins turned up today. Straight out the box, it has to be said they work brilliantly! The brick cladding of the stone bridge has started. They do not stick to the clay at all! Pattern is crisp and straight. The only downside, I can see and I have to say it was known when I bought them, is that they are Dutch brick pattern, not Flemish or English. That means they should be effectively the same as English, but I can't say I recognise the pattern as such! They seem to have put in a lot of random distressing, which I would rather have had a perfect pattern and done the distressing myself Although I have now had a go at two part silicon, my gun method is still viable (and cheaper) for less detailed, large items, such that I decided to have a go at making the stone bridge pier bases as a casting, so I did not need to make them repeatedly. I made the master out of Linka tiles and a bit of creativity and thought that I could cast it as thinly, by inserting some extruded polystyrene in the middle as an inner former to save plaster. In essence it works perfectly, only problem, is that even though I coated it in release agent, it is stuck fast inside the casting I could probably melt it out but there is no point, it's not doing any harm inside. Not wishing to make an internal former for every casting, I decide to have a go at rota casting it, first making the top, then rolling it around with two more batches of herculite, ensuring even coverage while it solidified. It is laborious and slow, but works. I cant say I would recommend doing it this way. The hardboard former The silicon gunned inner mould The two identical results
The 40 minutes I sat (like watching paint dry) slowly sloshing the herculite from end to end then roll over 180 degree's waiting for the point at which it was just about to solidify to ensure even coverage!
Some major Engineering work has broken out for the cable stay bridge! Given I have chosen Aluminium tube as the pillar material, I need to cross connect the two vertical posts to form a H shape. I have mused over many materials and methodologies, but as usual, have chosen the most robust engineering solution. {Things I build don't fall apart easily!} Thus I am using a section of the 18mm square tube as the cross piece between the 20mm verticals, although tests have shown that aluminium can be stuck with Araldite, the bond to the surface holds, but is very weak, so the actual structural connection is via a tensioning system. This consists of threaded rod couplers at each end of some rod and countersunk screws through the vertical pillars screw into it at each end. {If I still had access to TIG or MIG welding kit, then it would have been welded, as my preferred solution!} The picture shows it pre-assembled, before slipping the tube over the two rods and tightening up, with some Araldite to hold it in place, belt and braces.
I think that Aluminium could be a difficult medium to work with so mechanical means for fixing is probably your best choice.
Yes Toto, Ally, tis a bugger, life would have been much easier with some wood, but I build to last and did not want the wood warping! As said, much brain racking took place before I plumbed for the rod and couplers. I had considered a wood cross piece, tapped ends in plastic, clinch nuts, tapped steel, and many more. Apart from welding, a solid bar of aluminium with tapped holes would have been good, but the cost of purchasing even a meter was huge.
My website was originally just for my musings and a record of where I am up to, but over the years I have learned lots and wanted to give some back, so started writing pages to help others (read I am too lazy to keep repeating myself with the same old answers, to individual posts). Of course if there is a known website/page that has an authoritative guide/answer, then it is easier to direct enquirers to that URL, but many times there is not a known one! Thus not wanting to repeat information found elsewhere on useful sites, I started jotting down some of my gathered (and personal) tips and How to's and am slowly building a set of guides. In answer to one that comes up regularly from newbies on my other forum, I have just written up the latest, Gradients Guide. I don't proclaim to be an expert, so if you find fault/error/better idea's, then I am always open to criticism, good or bad, to aid bettering myself and the website.
Talking about gradients I saw a train (class 104 dmu) going up a steep hill once, it was on the A523 Macclesfield Road but this particular train was on the back of an Alleys low loader
Progress is slow, between working away from home and a sudden decorating project that broke out in the downstairs cloakroom, time for the layout has been minimal for a couple of weeks. The steel bridge is coming along slowly, as there was no base, I have had to create it with laminated strips of wood (bargain bin find, at B&Q) and edged by two pieces of aluminium angle at the sides. Not sure what colour to go for the wood? Grey for steel deck or brown to imitate wood? Also not sure about the steel colour. USA have a lot of black, in my mind UK should be grey, I know modern can be red/green/blues, but what was prevalent in the 1950/1960's?
Hi Timber Your bridge is starting to take shape now, looking good there. Sorry can't help you out regarding colours unless you want to use Meccano Limiteds palette.
Hi Timber, from what I remember as a kid in the 60's the steel bridge just down the road from where I lived was a grey/muck from the steelworks colour. However I have painted the sides of my river bridge with Tamiya "Dark (or Hot) Iron" which, to me, looks pretty good. Cheer's, Pete.
Further research on steel bridges gives no definitive result, they were many colours, might make it light blue, as that was the colour of many bridges I saw as a kid around Birkenhead docks. The stone bridge will be straight after the road exits from the cliff face, so a very flat stone tunnel portal is needed. I could not find anything that took my fancy, so decided to make my own! I made a flat sheet silicon mould with my gun silicon method, and added a lip (edge) with a couple of beads in the shape of the portal. Using DAS clay, I made the arch of the edge stones. Cutting a rebate in the cast to accept it then added the two vertical side elements. After some fettling, I added the right angle to the back of the edge stones. Can't decide if I should step the top corners?
The corners have gone! copping stones have been made and glued on, piccies to follow this weekend! While in the herculite casting mode, the other task that needed attention was something for the steel bridges to land on! The central pillars for the bowstring truss bridge will be of a different construction, but the end piers are to be of stone. The bowstring bridge needs a short end support pier (at the cliff edge), but the opposing end of the apex (arched bottom chord) steel bridges needs to be deep to accommodate the lower structure. In both cases they need to be double wide, not something available off the shelf. So I made a RTV silicon mould of a single, cast it three times and chopped it up into three parts and joined them back together. For the taller one, I also had to slice the front off and join on much lower and fill in the front above it, see pic. Now painted, they still need some weathering, but are essentially ready to be integrated into the scenery when the frame is built. I want to effectively build all three bridges then build the frame to exactly suit the finished dimensions, so lots more construction to crack on the bridges before I get to layout board construction. If anyone is interested in similar, speak now before they are incorporated into my layout and I will do new complete castings of them in silicon so they can be replicated later . There is a cost involved, so there may have to be some negotiations!
Oddly, the camera lies! I took the pictures under my fluorescent inspection lamp on my workbench and it doesn't do the casts any favours, the first coat of paint was green , so that the mortar looks like it is covered in algae (wet near a river), but that does not come out in the pics, when I weather them, I will take some pics in daylight, so that the proper colour may be seen.
Just twigged I am short of some detail items, namely if I am having a canal, it needs some narrow boats and if I am having a river, it needs some kayaks! A bit of www research and I have few options! Langley or Nock for kayaks and Craftline for pleasure boats. It has at least showed me a few more suppliers that are new to me, to add to my links page and I have put an order in for quite a few bits from Anyscale Models. I have also bought a hot air heat gun, not to do SMD work, but as a heatshrink shringer (fed up using my lighter) and for bending plastic. So I can now crack on with the middle steel bridge piers, as they have round sides in stone that would be a nightmare to cast, so I am using plasticard stone sheet, wrapped around a former. I decided on a olive green for the steel bowstring bridge, it is currently in the paint shop and has eaten 3 tinlets of paint so far !
Hi Timber Based on my experience. I have used Craftline for the canal boat on Little Weldon it was a nice little kit. Balsa wood with paper decorated panels. A lot of shaping required, the level of detail within the kit was just right for my layout.