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With grateful thanks to Trevor, ace 3D print maker, there are now running in boards for the new station. They are double sided, two prints for each glued back to back using two part epoxy with a 6" nail for the upright. They were then edge filled with Perfect Plastic Putty, sprayed white and the black infilled between the letters. The latter operation took several goes as if done for too long at a time the error rate became too high! I then went over the errors with white paint.
Being a sunny Sunday morning a couple of trains felt possible, first however it was necessary to correct some humps in the platform surface which arise when it gets warm.
Trefor did some circuits with the Plateway Models balcony coaches and milkvan. These are fresh humps!
Then Clara came out to play with the Ffestiniog wagons.
As can be seen in some of the videos the platform raised some more humps. Extra pins were added to flatten them out so the spacing interval is now about 50mm. Will have to see whether that works OK. The second Clara video is after the extra pins. The recycled plastic does seem to expand quite a lot.
gilfachphil wrote: ↑Mon Mar 11, 2024 9:47 am
I am hoping that by reducing the space between fixings the humps will become more of a minor ripple! Time will tell.
Phil
Phil
I wonder if you are taking the right approach to the expansion. Could the problem have been made worse by the nails preventing the plastic from expanding? A clue might be to see if the nails lift out easily when it is rippled.
I think you might be better allowing it to expand. What about slots under the pins you use to hold it down so that it can expand under the pins. You might need washers of course.
Phil.P wrote: ↑Mon Mar 11, 2024 12:14 pm
Nature, and physics, will always win..
I think you should let the platform have room to 'breath', as once we get some proper sun, I think it will damage itself?
Is there a thin surface, to the platform, or is it 'solid' plastics?
Phil.P
it's 3mm thick and on top of uPVC sheet offcuts.
I wonder if you are taking the right approach to the expansion. Could the problem have been made worse by the nails preventing the plastic from expanding? A clue might be to see if the nails lift out easily when it is rippled.
I think you might be better allowing it to expand. What about slots under the pins you use to hold it down so that it can expand under the pins. You might need washers of course.
The problem with allowing it to move is that there are fixed points within it. I guess I could cut expansion slots across the platform either side of the bits that need to stay fixed, but that might look unsightly.
I have more of the material so if this bit is ruined I can try another method with the remaining stuff.
As the weather warms up (?) even though I had put lots more pins in to attempt to keep the plastic down the wrinkles in sunshine just became smaller but more of them.
As an experiment I got some black 5mm foamboard at The Works and have replaced the short end piece with some of that. I'm not very confident it will do as in sunshine the unconstrained board curls up as the top surface behaves differently to the cooler underneath one. It has been glued down with UHU and weighted with bricks to keep it flat whilst the glue dried.
I have removed all of the pins from the long section and reduced the continuous length to a series of short lengths (around 13" each mostly). These I have pinned at one end leaving the rest free to allow it to move. Under each joint there is a piece of black plasticard to hide the white uPVC base. The joints have been made with 2mm gaps. I'm hoping that with hot sun on the material it will relax and go flatter (fat chance I wonder?).
I admire your perseverance Phil, but I fear that any attempt to use any kind of plastic, especially black, will end up as a variation on a theme.
FWIW, I have used white foam board as a sub base then painted that with SBR and spread "Postcrete" on top. It weathers to a nice gravel appearance and has lasted about 7 or 8 years outside so far. The weather got into it this past wet winter but some diluted SBR dribbled on to the cracks seems to have sealed it OK.