Author Topic: Bekonscot Model Building Materials  (Read 6108 times)

0 Members and 1 Guest are viewing this topic.

Offline IanT

Bekonscot Model Building Materials
« on: Sep 12 2010 09:35 »
We had a very interesting visit to Bekonscot yesterday, with (by my count) 23 Members and Guests attending.

After a pleasant individual tour of the gardens we were welcomed by Brian Newman-Smith (Managing Director) who kindly gave us a 'behind the scenes tour' of the "workings" and workshops. Although a Gauge '1' Railway, Bekonscot stock runs seven hours a day, seven days a week for two thirds of the year, so they have some interesting thoughts on reliability and how to build stock to deliver good running. However, this will be the subject of an article in the December Newsletter, so no more here.

What did attract Members attention was Brian giving a very strong recommendation as to their preferred building matieral for their model buildings. They have used a product called Airex PVC Foam Sheet for some time now and Brian showed examples of building components made with this material. More in the December Newsletter but for Members present who wanted the supplier details, they are as follows.

iMPAG (UK) Limited, Draycott Business Park, Can, Dursley, Glos, GL11 5DQ
Phone: 01453 890077 eMail: composite@impag.co.uk

Airex PVC Foam Sheet is available in different densities but BK mainly use C70.75 - it is also available in different board thicknesses, 1" was suggested as being most useful.

Finally, a thank you to Mike Williams for organising such an interesting visit.

Regards,

IanT

   
Nothing's ever Easy - At least the first time around.

Offline Ted Sadler

Re: Bekonscot Model Building Materials
« Reply #1 on: Sep 12 2010 18:32 »
I join you in thanking Mike for organising such an interesting visit.

I first came across Airex 30 years ago but had forgotten about it until yesterday. It is a 'closed cell' foam, i.e. under a microscope, a cross-section shows complete spherical bubbles spearated from each other by resin, that water cannot penetrate. In an open cell foam, the bubbles merge into each other, leaving passageways for moisture to penetrate. Rigid PVC foam is more malleable and ductile than rigid polyurethane foam. When impacted, it deforms but then more or less recovers its original shape, which polyurethane generally does not.

At Bekonscot, they are using it by itself for building construction, and very effective it is too. But there's another technique that is useful: you can bond sheets of card, plastic, glassfibre or other materials to each side of the foam to make lightweight "sandwich" laminates that are very, very strong and stable (even bullet-proof!). For example, I think it should be possible to make lightweight, removable, waterproof outdoor baseboards using an Airex sandwich on aluminium frames.

I'm going to try to make the platforms and building shells on my layout from this material. Maybe bridges too? Watch this space.

Regards, Ted

Offline MikeWilliams

Re: Bekonscot Model Building Materials
« Reply #2 on: Sep 13 2010 08:04 »
The real thanks should be directed towards the Bekonscot management who went out of their way to help us, keeping the refreshment kiosk open way after hours, opening up the workshops and even giving free tea and bickies.

This was the first time we had tried a non-garden GTG, and the next is in Derby on 30th October, so I hope you will give us the same great support you did at Bekonscot.

Mike

Offline Andy B

Re: Bekonscot Model Building Materials
« Reply #3 on: Sep 13 2010 08:11 »
As Ted has said, Airex is used as a core is composite structures, e.g. boat hulls, aircraft cowlings, cab and intermediate ends on railway vehicles - which led me to thinking that if anyone has contacts in this area of industry there may be the opportunity to get off-cuts for modelling use.

Thanks from me too for the visit - most enjoyable and informative.

Andy

Offline IanT

Re: Bekonscot Model Building Materials
« Reply #4 on: Sep 14 2010 17:16 »
That could be an interesting thought for Modular baseboards Ted (light + strong) - but I wonder at the likely cost of using Airex like this? What would you 'surface' it with?

IanT
Nothing's ever Easy - At least the first time around.

Offline Ted Sadler

Re: Bekonscot Model Building Materials
« Reply #5 on: Sep 16 2010 09:00 »
For outdoor portable baseboards, I have been trying to think how you could scale up some of the good ideas and techniques that are used in the smaller scales. At some of the recent model railway shows, I have seen consdierable advances in 'engineering' lightweight baseboard frames - e.g. thin plywood laminated beams drilled with enough holes to satisfy a Swiss cheese maker. The major challenge for Gauge 3 is making them from materials that are weatherproof and dimensionally stable under the loads we put on them.

I was thinking of PVC fascia cladding (e.g. soffit boards) as the outer layers of an Airex sandwich. You only need the actual track base itelf to be rigid and strong: the open scenery areas of a baseboard could be based on other, single-layer materials supported on the frame members. Textured areas like embankments could be formed with a base of chicken wire over suitable profiles, just like the smaller scales. Polypropylene mesh (sold as windbreaks for plants in garden centres) is another useful material.

I really would like to hear other ideas and especially to receive members' experiences of using different construction materials outdoors.

My ideas probably do not form the basis of cheap baseboard modules, unless you start comparing the costs against the rolling stock you want to run on them. I'm thinking of modules not only for get-togethers and exhibitions, but maybe also people who want to leave temporary baseboards oudoors on a patio, to run at weekends if they cannot build a permanent garden line.

Regards, Ted

Offline Christopher

Re: Bekonscot Model Building Materials
« Reply #6 on: Sep 17 2010 12:51 »
Members might also like to consider Styrofoam. It is the blue stuff. It is also a closed cell product and very light. I would suggest that if a 65mm board were sliced up into say 200mm planks and then laminated with a 9mm ply sheet that it would stand a fairly hefty weight and still be very light. Seal with resin if you felt it neccessary

Offline MikeWilliams

Re: Bekonscot Model Building Materials
« Reply #7 on: Sep 27 2010 16:06 »
Christopher,

Can you tell me more about Styrofoam?  The firm of that name seems to sell it in packs of 24 sheets only - or more! and it has a minimum thickness of 25mm.  I'm looking for a single sheet c5ft xc2ft 6in on which to mount some track to carry around to shows and Styrofoam stuck to a thin ply face or maybe even a hardboard layer would seem ideal.

Do you know of a supplier, or maybe it goes under a different name?

Mike

Offline Derek King

Re: Bekonscot Model Building Materials
« Reply #8 on: Sep 28 2010 00:03 »
Mike,

Have seen the pink type at B&Q, though think it only comes in a multi-packs, but could use it on a future scenic layout?!?

Derek.

Offline MikeWilliams

Re: Bekonscot Model Building Materials
« Reply #9 on: Oct 04 2010 13:26 »
Well, maybe its me, but I still can't find anything suitable.

I have a 3-way point that I'd like to mount onto a light-weight board so that it can be taken to exhibitions without damage, but isn't too lumpy.  I could make a thin plywood board the same conventional way basebaords are made, but I thought a piece of this stuff might work unsupported, and I could just cut it to slightly larger than the point.

Any suggestions, please?

Mike

Offline Ted Sadler

Re: Bekonscot Model Building Materials
« Reply #10 on: Oct 04 2010 22:56 »
If all you need is a lightweight support/base for the item at exhibitions, how about the card/foam/card sandwich boards sold in artists' materials shops? Hobbycraft in Milton Keynes (near B&Q), which I know is local to you, could be worth a look.

In an earlier post, I said that I was thinking about using PVC fascia board on portable baseboards. I saw it on a layout last week where it has been used as a platform surface, mounted on wooden supports. Unfortunately it has shrunk lengthwise in less than a year, leaving gaps in the platform. Back to the drawing board!

Ted

Offline Derek King

Re: Bekonscot Model Building Materials
« Reply #11 on: Oct 05 2010 00:17 »
Mike,

Still think Styrofoam edged in thin plywood or MDF would suit your requirements and would also be an ideal lightweight method of producing  Ian's "Standard G3 Modules".

There is an article in MRJ 156 on producing baseboards by this method, plus Gordon Gravett has used it on his latest (French metre gauge) exhibition layout.

Individual sheets are supplied by Trylon model suppliers of Northants (NN10 8HQ) - see under "Modelfoam" @ www.Trylon.co.uk .

Also, as mentioned previously, something similar is available at B&Q, though not sure if it is the same density as true Styrofoam. I saw individual sheets in my local store last week.

Derek.

Offline MikeWilliams

Re: Bekonscot Model Building Materials
« Reply #12 on: Oct 05 2010 08:09 »
Thanks Derek.  I had looked on B&Qs website and couldn't find anything like it, but the Northampton firm sound ideal.

For me this is what the forum does best.  Thanks.

Mike

Offline MikeWilliams

Re: Bekonscot Model Building Materials
« Reply #13 on: Oct 06 2010 08:17 »
Thanks again derek.  Pack bought from B&Q last night and looks to be just right.

Mike

Offline IanT

Re: Bekonscot Model Building Materials
« Reply #14 on: Oct 06 2010 09:29 »
I assume this is quite a dense material Mike?

As opposed to the kind of light polystyrene material that can be found used as pre-formed packing or for roofing insulation...

Also - how thick is it?

IanT
Nothing's ever Easy - At least the first time around.