The other week I posted the following in the Workshop section, but now I've started my build, so I'm opening a new Diary thread about it here...



Well, folks, it's thirty years since I made my first TARDIS model, and nearly ten years since I made the Cod Steaks 1:5 replicas, and I've got the itch again, so here goes:


I'm going to make a perfect full-size replica of a real-world Police Box, based on the surviving box at Crich Tramway Museum.


-  It will be correct in all dimensions and details, down to the slant on all roof ledges, and overlapping metal bars on the windows.

-  It will have correctly-dimensioned interior walls, hinging windows, hanging light etc - though I probably won't bother with the desk etc.

-  As I don't have room in the house, it will be fully weather-proof, to live outside.

-  It will also be easily dismantled and transported, to appear at conventions, weddings, bar mitzvahs, etc.

-  It will have proper "concrete" texture, by which I mean not a lumpy applied "artex" job, but a pitted surface, like the defects/air-pockets in concrete.

-  To achieve this texture, as well as the weather-proof/transportability factors, it will be cast in fibreglass.  I'd rather do a small amount of clever carpentry (making shuttering/moulds), and apply a nice texture to one wall, one post etc, then cast up multiples, than do lots of carpentry and texturing, that might fall apart after a few months.

-  For the window frames, I also intend to make one perfectly-detailed master, then cast them in fibreglass, adding correct pebbled glass, and blue panes.



Anyway, that's what I said last month, and here's a pic of me with the Crich police box, that Mark took when we went to take measurements.  We were there all day, but still got only half the dimensions needed, so another visit is planned...

OK, for the last few weeks I've been drawing up my diagrams, and ordering materials etc.

As I'm building this police box in my small back-yard, with no special tools more fancy than a cordless jigsaw, I got the wood-supplier to pre-cut the main rectangles of plywood, which has saved a lot of hassle.  (Except for the bits that were 100mm too short  )

I've jigsawed up the more fancy-shaped bits, and made a start on the BASE.

Most of the box will ultimately be cast in fibreglass (double skin, with expanding foam between, like a surfboard).  But I think the Base needs to be extra-strong, to allow people to walk on it, so I've built that out of 15mm Plywood, and coated it with fibreglass to make it weather-proof.

It was raining in Bristol yesterday morning, so I did the preliminary jigsawing in the kitchen, then assembled the whole base outside, in the afternoon, finishing about 10pm - glad it's summer!

Today I did the fibreglass coating.  Of course, it started raining just as I'd mixed a bucket of resin, but luckily it was a brief shower, and I got enough resin on to keep it weatherproof until I can carry on next weekend...

It's surprising how big the Base actually is, and it weighs a frickin' tonne, so I'm glad the rest of the pieces will be more lightweight....

It's also surprising how much resin is required - I can see this is going to cost a fortune!

Anyway, here are some pics of progress so far...


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I am digging the original approach to the base! Mine is so heavy I strained my back night before last and took two days off work to recuperate. I wish I'd built mine this way. Can't wait to see this box take shape!

You know, that is the first photo I've seen of the Crich box from that angle. Usually you see it from the rails, looking at the hill behind it. Neat!

Quote from: Elvis Gump on Aug 04, 2014, 12:20 am
I am digging the original approach to the base! Mine is so heavy I strained my back night before last and took two days off work to recuperate. I wish I'd built mine this way. Can't wait to see this box take shape!

Seconded - I know that pain!

I'm getting very excited by this build, I've been something of a lurker so far, I love builds of original Police Boxes and find them perhaps rarer and more intriguing than other eras of boxes, yet I simply don't know much about them so I don't feel like I can contribute! That said I have to pipe up because having been "wowed" at the start by true ambitions of the project I have again been "wowed" at the original take on construction and high standard of woodwork. And what's more you went yourself and measured the original - that's how it should be done!

Looks to be a great start Matt.

Hows the build going compared with how you planned to build it? Everything going to plan or are you having to adapt?

Thanks, Mark.

So far it's all according to plan, but this was the easy bit.

The big unknowns relate to the fibreglass casting of columns & walls etc.  Eg, how easy it will be for fibreglass to release from moulds with the "concrete" texture I want.  And what thickness of fibreglass will be needed to eliminate distortion...

I'm hoping to get on with some tests for that this week.....

Looks like a nice sturdy base, good luck for your build!
Wish I could helpmore with the fibreglass question, although half of my box is fibreglass I didn't do it myself and so my fibreglassing experience is limited to repair jobs here and there with car repair kits. And it's always a very unpleasant job. Karsten is pretty good with fibreglass from what I remember.

In my experience, the main parts of an outside box that need protecting (ie fibreglass) are the roof, top of the corner posts and signboxes. These areas really suffered on my box that has been outside since 2004 or so. In my recent rebuild I fibreglassed the top of the posts and signboxes  to stop rain getting in cracks. On mine the walls and doors are fibreglass,  I do envy those with wooden boxes for the sold clunking sound it must make when you shut the door.

You may be interested: Last week I visited Crich and took some photos. They've repainted her again, pictures here

http://tardisbuilders.com/index.php?topic=675.msg65480#msg65480

Thanks Manta - great pics of the repainting at Crich.  I'm looking forward to seeing it in the flesh...

Your police box is handsome too - another nice dark one :-)

Quote from: matt sanders on Aug 04, 2014, 01:00 pm
Thanks, Mark.

So far it's all according to plan, but this was the easy bit.

The big unknowns relate to the fibreglass casting of columns & walls etc.  Eg, how easy it will be for fibreglass to release from moulds with the "concrete" texture I want.  And what thickness of fibreglass will be needed to eliminate distortion...

I'm hoping to get on with some tests for that this week.....

I was think of doing something to my TARDIS as an undercoat that might help with your mold texture. Well, two ideas - one was to use a thin layer of that paint-on truck liner paint. I was thinking of painting it on and as it set up, use a paint knife to kind of slightly stucco it, to drag the knife over it the way you might with oil paint on a painting. I think it might give a "concretey" texture underneath the paint. If you did that to your mold pieces it might pick it up. The other way I thought to do it is with Bondo, which I had thought of doing the same technique with though I'm worried about the extra weight this would impart to my wooden TARDIS.

Now the idea of doing it to a pressure-treated outdoor TARDIS the weight might not matter at all. I think I'd like to try my hand at a genuine Critch style box after I get my 11/12 collapsible version finished.

The truck-liner stuff is very, very hard when it dries and very very heavy if put on full strength as the guys from MYTH-BUSTERS proved last season when they coated cars with it to see if it made them resistant to dents and dings (which it did). The weight of the stuff in a can versus dried/cured isn't much though.

But just to impart texture to fiber glass either of these might work. Might take a lot of testing to get a texture you want if it would work at all, but I thought I would toss it out there in case it might be useful.

Thanks Elvis, I'm not familiar with those products, but they sound interesting.

What I do have for the texturing, is Jesmonite Resin, which a a plaster-like powder, mixed with acrylic-based resin.  It can be mixed in various proportions, runny or thick, and tooled to give desired effects.

Here I am doing a test panel:





The tricky thing is trying to think in reverse, as I am effectively modelling the mould, so lumps in my resin with equate to recesses in the cast surface...


Meanwhile, I need to make the fibreglass castings release from it, so I bought some blue PVA Release Agent.  But then I saw that their website recommended first sealing the mould with wax.  So I bought some wax - and the guy who sold it to me said that before applying the wax I should first seal the mould with the PVA Release.

So - as the world is full of idiots, I'm trying all possible permutations of the two release agents, as shown below, to establish what works best...





Does anyone want to place bets about which release (and order of application) turns out best?  Hopefully I'll have an answer by Thursday...

Meanwhile, in other news - look what arrived today!  (Shome mistake, shurely...?)






I'm going for the Battersea Power Station look...

I know that when we measured the box we discovered the corner posts weren't truley square but I didn't realise they were that off!

I was looking at this photo of the Critch and I thought perhaps flattening and dragging some texture into whatever you use will give it that, well, trowled cement look. I suspect this part of the box had some sort of thin-set cement perhaps applied to it at some point to try to even out dinks and divots and chipped places in it's surface. Or to fill-in cracks in between things like the columns and sign boxes and such that might be letting water in over time.

I guess another way would be like trying to smooth out icing on the flat surface of a cake with a knife and not quite getting it super-smooth - that sort of texture.



The two things I mention, the truck bed liner would be this stuff



And the Bondo stuff is this which is used for repairing dents in car bodies



And there's this stuff that I forgot about which is similar.

That picture isn't a good example of the box texture as it shows one of the corner posts which was patched up last time round.

I took it to show the seams between the sign boxes and the posts.

I also think the sign front on the right was patched up too.

I know nothing of fibreglassing but your second idea sounds good - and the icing example makes great sense. I think that would give the box a great texture making it look as though flaking paint had been painted over again and again over the years.