[GreenBoy]

Hi Columbo

I note you recommend the use of vibration to shake the air out of the plaster - may I suggest another way of doing this that may be rewarding (or certainly worth trying)

Years ago my father and brother had a business that cast figures and building for model war gamers, and we used to cast in resin, but on the odd occasion we also cast in plaster (primary reason is although it does harden it can still be filed, shaped etc. allowing you to use the casting for making variants) - there are different grades of plaster - dentists being the hardest, and you can even add reinforcement in the shape of fibre.

To ensure our castings were bubble free, and avoiding unsightly holes and blemishes in the final piece we used a vacuum chamber to pull the air from the plaster or resin. This is best done in two stages - the fist when the plaster has been mixed and then once the plaster has been poured in the mould

Now before you panic, plaster only needs a couple of bar - 5 at most, and this can be achieved in stout plastic box - as long as you can make it air tight on the opening. 5 bar is achievable with a hand / bicycle pump...

lastly ensure you lay the mould on a perfectly flat and level surface to minimise warping. Note - you will get shrinkage with plaster to always slightly overfill and then be prepared to sand the back down - after the plaster has fully set!

Unfortunately my fathers business folded in the last recession and I no longer have access to the equipment to put a better step by step guide together here.

If any one wants to give it a go I would be pleased to hear of it, and help with anything I can remember (I used to work for my Dad every weekend in the casting shed - so have a little experience

)

GreenBoy

 

[patrick draper]

A truly excellent model. An inspirational piece of work. Something to aspire to for me. I am modelling Doncaster Station in the mid 50's early 60's so am the previous or next large station along.
Well done, I read an article about York in this month's RM and was very impressed.

 

[Colombo]

Patrick,

I too enjoyed reading about the excellent model of York Central by Ken Harland in the RM. I only hope that my version can ever achieve the same state of completion. I still have to scenify one end and also the operators side of the layout.

If Ken Harland reads this, I would like to hear from him. We must have a lot in common to talk about.

I have recently had a most interesting visit by a panel of real railwaymen who have advised me on the correct way to signal my model. I shall be using colour light signals and I have so far added only 4 of the 16 needed. Then I need 6 platform end starter signals, a home with a theatre indicator, and the first 4 aspect block signal on the up main line.

For the latter, I have purchased an Eckon signal ES4 and a Mas-Seq-4 module from Heathcote Electronics. This uses Infrared technology to detect a passing train and turn the signal to red. Then it cycles automatically through yellow and double yellow back to green.

Colombo

 

[Khris]

Hi Neil,
You said:"My next problem is how to get all this stuff locally "
Barnes in Swan St Richmond handle rubbers epoxys and all things casting.
One Stop Plastic Shop just off Boundary Rd East Bentleigh also handle same.
Both good to deal with.

HTH
Khris

 

[upnick]

Hi All,

While looking through this section of the site i was reminded how excellent this thread is

hope its useful

 

[Big Dave]

What a great thread. Thank yo,u just the thing I have been looking for as I have made a start in working with plaster I think plaster work look so much better on a layout just got a load of air drying plaster so will have a go at making some more mouldings. As Nick says this is a great place for all sorts of info

Regards

Dave