The slaughterhouse is fading

No, this is not a post about my becoming a vegetarian.  It concerns the slaughterhouse at my model of St Petrock station.  

With a keen eye to boosting profits on their North Cornwall lines, the London & South Western Railway opened slaughterhouses at Halwill Junction, Holsworthy and Bude. The photo above, of the one at Halwill Junction, was taken in 1960.

It seemed only right that St Petrock should also have a slaughterhouse, so I built this one in 2014. At this time the rest of the station was far from complete, so I placed a piece of temporary backscene behind it.

Here it is, nine years later. I'd printed the brick and roof tile papers on my old HP printer and the intervening years have not been kind to them. The 'bricks' have lost their red colour and the roof has faded noticeably. Thankfully, those printed with my present HP Envy 4524 have fared better. 

According to the instructions that came with the ScaleScenes download, I should have sprayed the printed paper with matt varnish, so to halt the deterioration in the other older buildings at St Petrock I bought this...

... which promptly turned the roof tiles white!  Fortunately, hand-brushing on a coat of Ronseal clear matt varnish restored them to their former faded state, but I predict that a new slaughterhouse will soon be making its appearance.

In the mean time, if any of my loyal readers can suggest which spray-on varnish I should have used, I'd be very grateful. I must take steps to preserve the many other buildings at St Petrock and Bourdon Mill.