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Matt's Replica Crich-Style Police Box

Started by matt sanders, Aug 03, 2014, 10:41 pm

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Elvis Gump

Aug 15, 2014, 04:59 am #45 Last Edit: Aug 15, 2014, 05:00 am by Elvis Gump
Quote from: matt sanders on Aug 14, 2014, 10:49 pm
IMG_1358.JPG


I've thought of how I might replicate this and the best I've come up with is to cut my plexiglass into individual frames and using a solder or wood-burning iron with a cap nut on a piece of all-thread inserted in place of the solder tip and seeing if I could melt those half-spherical shapes from the back-side of the plexi. I'm going to try it on a scrap piece this weekend and see how it works.

cap nut.jpg

It would be great if you could provide a shot of these with a ruler for scale, especially the top light. I've thought of trying to turn a wood or PVC piece on my lathe and make a mold. Since mine won't live outdoors, I might be able to get away with a cast acrylic fresnel until I can find an afford an appropriate one.

You're my hero for having the audacity to pull these pulls off - pun intended

galacticprobe

Aug 15, 2014, 05:18 am #46 Last Edit: Aug 15, 2014, 05:28 am by galacticprobe
Elvis, as someone coming from an electronics background, I should say that you'll need a high-wattage soldering iron. It's going to take a strong heating element to heat up those rounded cap nuts, and you'll lose some of that heat each time you touch the domed nut to the plastic. (SAFETY NOTE: Also, beware of any burning plastic smell: not healthy to be breathing that in since Plexiglass is a plastic, which is a petroleum-based product, and what you'd be smelling are fumes from that.) Best to do that in a well-ventilated area, which is another reason why you'll need a strong soldering iron: well-ventilated area, more heat loss.

You'll also probably have to do some fine sanding once you're done melting in your "dimples" as some of the plastic will bulge out around the area you're melting the dimples into - like a slow meteor impact; you'll be pushing material out of the way to make the dimple, and that material has to go somewhere so you might end up with little craters with "crater walls" that will have to be levelled out. It might take some doing, but once you have levelled the surface and have only the dimples left, some wet sanding with really fine grit sandpaper should polish the plastic clear again (or very near to it).

Just really watch out for those fumes!

And, matt sanders, I also have to admire your guts with forming your moulds. As we say in the States, you've got some serious nads! And well done on those moulds!

Dino.
"What's wrong with being childish?! I like being childish." -3rd Doctor, "Terror of the Autons"

Elvis Gump

Firstly, Matt thanks for these wonderful reference pictures. I will suggest a ruler in the shot the next time you do this so there's a reference for scale. One trick is to either glue a little wood block to the back of a ruler so it can stand vertically or horizontally so you don't have to hold it in place while shooting. Hot-glue is great and lets you remove it later.

Secondly at the risk of thread jacking - yeah Dino, I also thought of trying to find some metal in my shop, preferably something soft like a piece of aluminum, cut it to size and come up with a way to grind in the dimples, heat it up with say a propane torch and then smash it down onto plexi or leave it on say a square of concrete pad and smash the plexi on it - probably the best way I think. I must have a couple of dozen round-ended grinding stones for my pneumatic die grinder, others for Dremel and so on so I think I can get close without shopping. I keep thinking about things like this when I'm at work, stuck in traffic, in line at the register. I start to see TARDIS parts and ideas everywhere.

Of course if I used the heat method I would do it on the porch of my shop to avoid breathing too much of the fumes. Since it's the American South and the heat on some days gets up to 100-degrees here, believe me I have several fans going full-tilt boogie at all time so it's like a wind-tunnel out there! No shortage of ventilation.

I figure I can come up with something if I screw around a bit. I also thought with the cap nut not heating up to fast, I'd just screw it into a makeshift handle and heat the nut with my torch.

I'm looking to make my pebble/hammered glass look stuff from something scratch made. If all else fails Lowe's has this film that simulates that glass look that one can apply from the back, but I think it only really works if there is defused light coming from behind. I think something dimensional would be better. I've even thought of making plaster casts and having a friend with a kiln melt me some glass into them as she already does some pretty cool glass and pottery stuff with her kiln.

The most important thing is coming up with something to accurate scale, that's why these casts intrigue me so. Getting close to the real thing would be really cool to achieve.

One thing that I think might work for the top light fresnel would be to glue up some of those PVC trim boards, cut it to the correct dimension and then spin it on my lathe. I've made some smaller bits with it on my lathe before. It's great stuff to work with to make say decorative corbels or stuff that you want to be rot-proof. It's insanely expensive compared to wood, but it's not an entirely bad idea for a lot of outdoor TARDIS parts.

I think I could get a pretty smooth positive that way that I could make a plaster or silicon mold from to pull a cast from. When looking at a couple hundred bucks for a real lens that could get broken taking the TARDIS someplace, having a mould to pull some clear acrylic casts from seems more economical in the long run. I'm not sure if anyone else has ever tried that and I'd be interested in knowing what results they might have had.

Lastly Matt, what are you going to do with all those moulds? I can't wait to see some 100% Police Box vintage glass!

matt sanders

Elvis - before you start grinding your plexiglass, remember the actual pebbled glass on the door has lumps that protrude, not recessed hollows.

(The opening windows on the other walls do have concave "hammered" texture, but that's a very different pattern.)

If you know someone who can cast glass off a plaster plug, perhaps you should instead grind your dimples into a flat piece of plaster, so the glass gets domed lumps...?

As for size - the panes in these images are:
WIDTH:  3 1/8"
HEIGHT:  6 1/2", up to 6 5/8" in places.

Note that these are panes from the non-opening windows on the Door and adjacent wall.  The opening windows on other walls have smaller panes.

hb88banzai

Aug 15, 2014, 09:38 am #49 Last Edit: Aug 15, 2014, 09:49 am by hb88banzai
Quote from: matt sanders on Aug 14, 2014, 10:49 pm
(snip)
So - the big question is - did this box originally only have ONE type of glass, and if so, which is the earliest?  If the door's glass doesn't match the wall's, is that another indication that perhaps this door was a later replacement...?


I can't speak for Crich as originally installed, but the following photos suggest (to me at least) that the "pebble" type currently on the doors is by far the older (and in fact appears to be the only variety represented here, if I'm seeing them correctly):

A Mark 1 (installed 1929, photographed approximately January 1931) --
Mark1Windows-c1930-1931.JPG

A Mark 2 (installed and photographed circa 1931) --
Mark2Windows-c1931.JPG

The Barnet very early Mark 3 (installed 1935, photographed in the late 1970's) --
BarnetWindows-clate1970s.JPG

And a very late Mark 3 (built 1937, photographed circa mid-1960's) --
LateMark3Windows-c1960s.JPG

And finally, the Wimbledon Common Mark 4 (likely installed some time in the 1940's, photographed 1959) --
Mark4Windows-1959.JPG

The "pebbles" all look quite hemispherical and a bit separated instead of running together, though the resolution and lighting are of mixed quality.

Volpone

In no particular order: 

1) I'd love to see a color photo of that early, early box.  That blue is so light I can't even imagine what it looks like. 
2)  It is interesting to see that the blue lightened up in the 70s, after the early 60s boxes.  That Barnett photo (and one that was my wallpaper) are a relatively light blue, compared to the current color on the Crich or the photo you shared of the Barnet from the '60s. 
3) I forget what 3 was for. 
4) The theory I've had for replicating pebbled glass was additive rather than subtractive.  I thought about using dots of silicone caulk, but I don't think the shape or texture would be right.  And I suspect the melting point on Plexiglass would be too high to get good effect by taking a blowtorch to it at any practical height over a pane.  You'd have to have the equivalent of a shot tower like was used in Olden Dayes for casting firearm shot.  And then good luck getting decent coverage of a pane.  The best I can come up with is some kind of gel adhesive and rolling it into balls and sticking it to a pane. 

Of course this is far down on my list of projects.  But if anyone wants to pursue it, just share the results with the rest of the class. 
"My dear Litefoot, I've got a lantern and a pair of waders, and possibly the most fearsome piece of hand artillery in all England. What could possibly go wrong?"
-The Doctor.

galacticprobe

Aug 16, 2014, 04:46 am #51 Last Edit: Aug 16, 2014, 05:44 am by galacticprobe
Quote from: hb88banzai on Aug 15, 2014, 09:38 am
The "pebbles" all look quite hemispherical and a bit separated instead of running together, though the resolution and lighting are of mixed quality.


Well, I know I'm reaching with this one (but that's what a heavily-medicated mind is for, and today was so achy that I did take some extra meds). Anyway, take this for what it's worth and let me know just how insane in the brain this idea is. Going by HB's observations and this pane:
LateMark3Windows-c1960s.jpg
which shows what he's taking about quite well, it might be possible to create a pattern for this to pour a mould from.

I don't know if these things still exist, or if they were sold outside the US, but how many people remember those sugar candies that came in little domes like this, and attached to what looked like calculator/cashier tape paper? (You know the kind: no matter how hard you tried to pull one off to munch on, you always ended up taking a good chunk of the paper backing with it... and more often than not, eating it with the candies.)

Now, just supposing this candy still exists and can be bought for what I'm guessing is still a pittance. Now also suppose you have a piece of thin, smooth wood or plexi (about 1/16th-inch thick, but for strength you could go as thick as 1/8th-inch). You could pull those candy domes off of the paper (hopefully having better luck leaving the paper behind this time), and with a little dab of glue you could stick these candy domes onto the thin wood/plexi so it looks like the pane above. Once it all dried you could brush on some sort of sealer (those candies are porous) and when that dried, after a little spritz with some cooking spray for a mould release you could pour a silicone mould over it.

Once the silicone sets and you pull it away from the "candy form", you'd have a mould with a good match for the pebbled glass as HB describes it. Then you could cast as many pebbled panes as needed. (If you have to pull some of the little candy domes out of the silicone because they broke loose when you pulled the mould off of the form, just don't eat the candy. I say this because I would try to eat it! Aaaand hopefully my wife would be on hand to stop be before I did.)


  • Candy domes on paper strips (if you can find them) - a few dollars at most to get enough;



  • Thin, smooth wood or plexi for the "glass" part of the form - another few dollars from a hobby or craft store;



  • Glue to stick the candy domes onto the wood/plexi - no cost as we most of us have different types of glue at home;



  • A sealant to cover the porous domes - again probably no cost because most of us have something of the sort already;



  • A mould release - once again, probably no cost as Pam Cooking Spray works wonders, and I heard that from a professional model-builder;



  • Silicone to pour the mould with - (not sure, but no doubt a decent amount at hobby/craft stores);



  • Clear resin to cast the pebbled panes with - (again, not sure; it's been a while since I've gotten this, but probably another decent amount from a hobby/craft/home improvement store);



  • The end result when you pop the newly cast pebbled pane out of the mould -  :o PRICELESS!



Okay... so, how plausible is that? (It's certainly easier than trying to drill/dig/melt in concave dimples to make a form, and then trying to get a "positive" casting from that.)

Just my two brain cells' worth (and one of those brain cells is dedicated to autonomic functions).

Dino.
"What's wrong with being childish?! I like being childish." -3rd Doctor, "Terror of the Autons"

hb88banzai

Aug 16, 2014, 11:02 am #52 Last Edit: Aug 16, 2014, 11:39 am by hb88banzai
Now that brings back memories!

Great idea, but I'm not sure they would be big enough. From the above figures and photos it looks like they would have to be about 3/8" in diameter at the base. It's been so long, I really don't remember how big they are.

Regardless, I think NECCO still makes Candy Buttons at around $1 a strip. Certainly worth a try at that price, if they are anywhere near the right size. Nice thing is that they vary a bit in size, so it would help achieve the slight variability we see in the originals (especially the older ones).

At 3/8", I think you'd need somewhere around 150 of them per pane - you would have to make them a bit over-sized in order to have partial pebbles randomly along the edges. You would also want to make at least a few different pane moulds to change up the pattern.

Elvis Gump

Aug 16, 2014, 04:58 pm #53 Last Edit: Aug 16, 2014, 05:15 pm by Elvis Gump
I'm thinking now of using one of those round nose router bits, using it in a drill press to make the depth half spherical like the 'pebbles' into a blank of PVC board for smoothness and no grain and drilling the pebbles in negative for a mold. There's zillion sizes of those round nose router bits, I just need to know the 'diameter' of the pebbles to get the right bit size.

round nose router bit.jpg

Then once the pebble field is made build up the sides with a lip for squareness, correct dimension and depth and then poor clear acrylic resin in with mold-release to get them back out and that would be a way to make panes. Make say three  or four slightly different molds so the pebbles look random-ish and by putting each pane side by side in the window frame varying which mould they came from it would achieve the look that every frame was "different".

The advantage here is also if one wanted to pour a plaster mould, this could be used as a master to make a plaster negative and melting real glass into it. I think. I have to ask my friend if I could try to melt some real glass into a plaster mold in her kiln.

matt sanders

With regards to making home-made pebbled glass:


When I did the tooling for the Cod Steaks 1:5 TARDIS, I rolled out some plasticine, and repeatedly pressed a little ball into it, to make the required pattern.  I then poured in resin, to create a panel with the necessary domes, cut it into rectangles, and made a silicone mould from that.  Obviously, those panes were much smaller, but I expect the same principle would work full size.

Indeed, looking at my silicone moulds from Crich, I wonder if that's how the original pattern was actually made, by pressing a ball into clay.  There are even a couple of places where you can tell which order the dish-shapes were made, as one is distorted by its neighbour.

The thing to bear in mind, is that the domes on this pebbled glass are NOT full hemispheres.  Whilst each dome is approx 8-9mm wide, it only protrudes by about 1.5mm.  This means that the size of the ball that gets pressed into the clay, is actually probably about 15mm in diameter, as indicated below....

Pebbled Glass Mould Proportions.jpg

If I can get hold of some ball-bearings, I could lay them in the mould, to see if my 15mm estimate is accurate or not...

Elvis Gump

That should be easy to replicate then. Knowing the size is everything. I think it will be a great mod to the windows for my 'modern' series TARDIS to have such pebbled glass windows if I can pull it off. I'm about to get to work on the sign boxes so I'm still a ways off, but this will prove to be something I can tinker with in the odd hour or two till I can get it right.

Thanks a million for the info Matt!

matt sanders

Hi folks,

Back in August I was making good progress with my replica Police Box, but then I got ill, so had to put things on hold for a while.  (At one stage it even looked like I might have been poisoned by the fibreglass chemicals that I was using to make the box, which rather dampened my enthusiasm for the project!)

Anyway, by the time I was better, I had to spend all my spare time repairing my house's front door and rotten frame, ready for the winter, so I've only recently got back to the grindstone...

I've concluded that it's now too cold to be making big fibreglass components out in the back yard, so for the moment I am concentrating on the smaller details, that can be made in the kitchen. 

A couple of weeks ago, I made another trip to Crich, and made silicone moulds of more components, including the Lamp Base, Lamp Top Dome, Various Window details, and both Door Handles...

So - stay tuned for pictures of my replica Lamp, in the next few days...  ;-)

Elvis Gump

I know the feeling. I was zipping along and hurt my back at work and lost a lot of steam. I'm still working on mine in small fits and starts, but had to wait until I can get some extra tools and stuff I needed.

Can't wait to see your box build progress!

galacticprobe

Dec 04, 2014, 08:03 pm #58 Last Edit: Dec 04, 2014, 08:07 pm by galacticprobe
Whoa! Matt! Sounds like you had a really bad turn! I'm so happy to see that you've recovered from your illness. (I hope it wasn't fiberglass poisoning! Maybe just the resin fumes got to you? Anyway, you're all right now, and that's all that matters.)

I, for one, am looking forward to see your renewed progress. (And to be extra safe: this time wear rubber gloves and one of those "fume filtering" masks when working with the fiberglass resins. I would hate to see you fall ill again. Forget worrying about seeing your build completed; I just want to see you stay healthy!)

And the way you keep getting moulds from the Crich box, by the time you're done with it, you could feasibly have the entire box moulded! (Especially since no one seems to be bothering you while you're doing all this. Do you have a perception filter that you're using when making moulds out there?)

Dino.
"What's wrong with being childish?! I like being childish." -3rd Doctor, "Terror of the Autons"

hb88banzai

Ouch! Sorry to hear you were ill, Matt - certainly explains the sparsity of posts the last couple of months.

I concur with Dino - even if not the direct cause, the toxic fluids and fumes inherent in working with resins and many paints are definitely something to be very careful of, especially indoors.

Hope things keep getting better, and can't wait to see the results of all your research and hard work. Been waiting for someone to do this for years!

8)