The Kenneth Sharp Tardis Console

[andrewkent]

Hi Steve, it's possible that the table needed to be in the right place, but the control panels themselves may have been fitted starting in a different position each time. If they were all wired to their own battery packs they could be placed anywhere.  This would explain their random positioning during Seasons 15,16 & 17.  Although for this to work post Logopolis the keyboard chameleon attachment must have been removed.  Can we tell by the markings on the side of the table whether this is true?

PS - I think I met you at Small Space - we both stood admiring the Whomobile!  Next time I'll say hello!

Andrew

[Rassilons Rod]

Didn't the chameleon keyboard pop again once later?

[galacticprobe]

See what I mean, way to complicated and time consuming. The simplest option would have been use batteries where possible.

And in this I completely agree. With our modern technology these days and mains-to-+6Vdc adapters being so much smaller and lighter-weight, someone wishing to replicate this version of the console could use those as the "Blinkies'" power supplies, and never have to worry about leaking batteries.

I'm not sure they mean the Five Doctors when they talk about the change in lighting method. Looking at this screen cap from Warriors' Gate, you notice that the lighting inside the each of the shafts has changed to a single continuous lamp.

However in this screengrab from Full Circle Episode 4 (the story filmed immediately before Warriors' Gate) you can see the original lamp configuration.

They obviously gave the rotor lighting a serious overhaul in between the two stories and when you look at this screen grab from State of Decay episode 1, I think you can see why.

Oh yeah; those light fixtures inside the cylinders are definitely falling apart! And the way that snippet interview is worded is a little on the vague side when it comes to determining exactly what's meant by "A more up-tp-date approach to a power source didn't come until very recently", as from there the conversation reverts to the much earlier "Stones of Blood" episode and the column's ("Time Rotor") operation. Maybe it was in "Warrior's Gate" when the power supplies changed - along with the new lighting tubes inside the large cylinders.

Its also during this refurb that the shafts get thier little domes on their tops...

The new lighting configuration looks to me to be a T5 fluorescent tube which would, be mains powered and would need a ballast control gear in order to operate. I'm guessing its this refurb that that they refer to when they say that they changed the lighting to a more technically complex method and removed the batteries.

Again I agree there. This could have indeed been the "more up-to-date" power source mentioned. (Sort of removes some of that vagueness.) As for being more technically complex, perhaps that refers to how they had to wire in those T5 fluorescent tubes - which could have had something to do with those little silver domes being added to the tops of the red cylinders. Lighting fixtures that accepted those T5s can be easily taken apart, and the connections for the tubes used while everything else bulky is discarded. Fixtures that small also didn't always need those large (what we nicknamed in the military) "ballast bricks" to operate the T5 tubes; many of them had those small cylindrical "cans" (a.k.a. "starters") that took the place of large ballast controls. (I have several of those that I use for Halloween lighting; the housings are large, but the end connections for the tubes and those "starters" are small comparatively. Talk about wasted space inside those housings! Nothing but wiring.)

And just so people who aren't familiar with electricals or electronics know what I'm referring to:

Here's one of those end connections; you'll find one at each end of a fluorescent tube. This is where the wiring is connected to (those flat openings at the bottom), and then the tubes slot into the ends and twist to lock them into place. One of these could have been at each end of the new T5 tubes in the cylinders (top and bottom) with the silver domes helping to cover the ones on top, while the wiring went in through the domes (and those wires are visible in some scenes)...


...and one of those "starters". They come in different looks and casings, but they're not much larger than about 3/4ths-inch in diameter, and about 1.25 inches long. Those two terminals on the end plug into the wiring via a socket mounted just inside the fixture's housing. (Like the fluorescent tubes, they slot into the socket and then twist to lock in.)

On a side note, the operation of the new lighting appears to change from story to story. In Warriors gate its only the shaft lighting that is operating (and that is flashing); however in Logopolis the lamps are continuously one, but the blinkies have lost the random aspect of their flashing rate, and are now flashing flashing all together at a steady pulse.

As with anything "TARDISy", the only thing consistent is the inconsistency.

If you jump forward to Castrovalva episode 1 the shaft lighting is again continuous, however the blinkies are again flashing, but this time on a "half and half" basis, with the Blinkies on two sides of the central pier on together and then swapping to the remaining pier lights coming on a few seconds later.

Hey, they've got to keep things mixed up to keep us guessing! (Where's the fun in predictability? )

(I tried to capture the change in the two screengrabs above; however you really need to see it in motion to get the gist... ) The same configuration occurs in Four To Doomsday (the next story in production after Logopolis).

Agreed. I think we know what you mean, and most of us can visualize it.

The simplest method of achieving this would be through the use of a two channel controller, which would alternate the power between its outputs, giving the flashing effect described above.

Well, trying to keep things simple, going back to that Lamp Flasher circuit (this post: http://tardisbuilders.com/index.php?topic=616.msg73221#msg73221 - read down a bit for more on the circuit... with the video link to it in this one: http://tardisbuilders.com/index.php?topic=616.msg72819#msg72819), this sort of flashing could be achieved with a simple NE555 Timer chip (to provide the flashing: flash rate and "fade" time totally adjustable), with a power transistor like the 2N3055 to handle the current for all of the "blinky" lamps. You would just need one 2N3055 for each "lit" side (in the above case, one for the two sides that are on at the same time, and another for the third side when it comes on: so two 2N3055s). The circuit is small and practically bulletproof. (Those NE555s and 2N3055s can really take some abuse and be very forgiving.)

Using multi-channel controllers, especially back then, would have been much more complicated, and given the column's lights another way of breaking down. The simple alternating flasher circuit like the one above would have been very inexpensive and fast to build, and with some variable resistors in there all it would take is the turn of a knob to adjust the flash rate. (Fade rate wouldn't have been an issue when using incandescent lamps, but would be a consideration if someone wanted to build this column today using LEDs and wanted to have that incandescent look to it.)

Now I've not had the time to review every episode the console features in; however given that the flashing nature of the column changes between stories I'm willing to guess that the connections for the two channel controller were not actually marked up and the connections were made depending on the personal preference of the stage hands that put the console together on a story by story basis...

Agreed again on the electrical stage hands and their connections, but the rest could still be the result even if using the alternating flasher circuit, especially if one of those flash rate knobs was bumped during the prop's take-down or set-up.

I hope some of this makes sense.

Dino.

[fivefingeredstyre]

[fivefingeredstyre]

Having real trouble posting today...

AS you can see from teh picture above, the domes that were eventually added to the shafts were really just window dressing...

[galacticprobe]

That image is posted in another thread, one I came across a while ago. That's what made me think those domes could have helped hide any wiring that went into the top for the upper part of the T5 tubes. (Window dressing is great for hiding things.)

That image also shows you just how thin the wall of that central column cover really was! And if you look closely at it, you can see the little holes around the top edge where the top disc was bolted into place. (Now I don't feel so bad about the packing tube I snagged when the wife bought some large, outdoor Christmas ornaments last year (2014). If the BBC can use something that thin and make it look decent, then maybe I can, too. (Now I just need some room to start that console.)

It looks like they've just stuck that column in a 'hole in the wall' place for storage. It's no wonder the poor thing looked as rough as it did at times during its life.

Dino.

[warmcanofcoke]

From this picture it looks like the perspex cylinder wall is about an 8th inch (3mm) thickness. I wonder if the Mike Kelt console also had a time rotor wall of a similar thickness.

[galacticprobe]

Well, while I admit I've never been all that great with guesstimating some measurements, using those yellow supports at the tops of the red cylinders - with the one on the right side being an almost straight-on edge view - it looks like that column cover is closer to the yellow supports' thickness. Those supports don't look like they're 1/8th-inch thick: maybe 1/16th-inch thick, which still makes that cover quite thin. (Granted not as thin as I first thought, but still thin.)

I think we'll need Tony's amazing calculation methods to help figure that one out more closely, and get a better idea of the "as built" cover wall thickness rather than its "as intended" thickness.

Dino.

[fivefingeredstyre]

From this picture it looks like the perspex cylinder wall is about an 8th inch (3mm) thickness. I wonder if the Mike Kelt console also had a time rotor wall of a similar thickness.

It's also got a chunk taken out of it on the left hand side of the seam

I'd have said it was thinner than 3mm (1/8"). The seam down one side makes me think that it was rolled and kept in shape by the top disc. I doubt if you would have been able to manually roll a sheet of acrylic 3mm thick. If it was 3mm acrylic you could probably have just got hold of an extruded section of the right diameter. I'm wondering if it was made from an acetate sheet?

[tony farrell]

As we're about to discover....... The cylinder was made from 1/16th thick Perspex (1.5mm metric equivalent).

More to follow!

T

[fivefingeredstyre]

Are we sure about it being perspex? I'm with you on the thickness, but I'm not sure an acrylic of that thickness would be flexible enough to roll round on itself without snapping? I could be wrong, of course?

Also why manually make the cylinder  with acrylic and join it with a visible seem? You could have had some extruded at the right diameter as a single continuous piece and no seem would have been required?

I definitely think the top of the cylinder is an acrylic disc, as it would have needed to have been solid enough for the cylinder tube to fix to, but I do wonder if the cylinder tube was actually made of something more flexible like an acetate sheet?

[galacticprobe]

Are we sure about it being perspex? I'm with you on the thickness, but I'm not sure an acrylic of that thickness would be flexible enough to roll round on itself without snapping? I could be wrong, of course?

If you heated the perspex in some way then it would be easy enough to bend around a former (like one of those cardboard tubes for pouring concrete posts). Heating it could be done in several ways: large heat gun, large oven-type device, etc. Once you soften the perspex it bends. I think M.D. used a heat gun when it rolled his column cover for his console.

Also why manually make the cylinder with acrylic and join it with a visible seem? You could have had some extruded at the right diameter as a single continuous piece and no seem would have been required?

From what I've seen in recent times, extruded tubes are very expensive. That would indicate the process if extruding them is expensive (since the perspex or acrylic isn't that expensive). Back in the 1970s when all productions were feeling the squeeze of budget cuts, they might not have had enough in the budget after revamping the console to afford an extruded acrylic or perspex tube. (Just guessing on that, but it's plausible at the least, and I could just see some poor sod in the props department standing over a sheet of perspex that's on top of one of those cardboard tubes, blasting it with a heat gun and slowly rolling it as it softened and started conforming to the cardboard tube.)

I suppose if they had access to a large enough heater and vacu-forming machine, they could have vac-formed a complete cover (including the top), but they would have needed a sheet of acrylic/perspex thick enough to handle the stretching over the master form and then the vac-u-jack as it sucked the air out, stretching the perspex even more as it was drawn against the form.

I definitely think the top of the cylinder is an acrylic disc, as it would have needed to have been solid enough for the cylinder tube to fix to, but I do wonder if the cylinder tube was actually made of something more flexible like an acetate sheet?

I agree on the cylinder top; in some images it looks like it could be 1/4th-inch thick (thick enough to hold the cylinder, and not split/crack when those little screws holes were drilled, and then the screws were driven in). The acetate sheet is also plausible, and one that's 1/16th-inch thick "should" be flexible enough to bend since acetate is more flexible than perspex or acrylic.

I hope some of this makes sense. And now we've been given a nice teaser (Thanks, Tony!), so we do have some more info on this coming. We just have to wait.

Dino.

[tony farrell]

Well, firstly an apology for the delay in replying - it's been a busy - and expensive - fortnight (as Steve W/Fivefingeredstyre will testify - more of that later)! But I digress....

I left this discussion with a somewhat confused state of mind: Why - according to The Technical Manual -  would an apparently symmetrical hexagonal table only fit one way on an equally symmetrical plinth. Why would the stagehands sometimes have to take half-a-dozen goes to get the table section to fit correctly?

Well, thanks to Steve W, we have seen that once the chameleon circuit programmer (and its associated raising mechanism) was removed, the table could indeed (once again) be fitted in any orientation and that therefore there was nothing inherent in Kenneth Sharp's design which would have prevented this! So, my drawing of the main components holds true. I'm somewhat relieved by this!

A second point to note in the preceding discussion is the alterations carried out to the central column due to the obsolescence of the tungsten filament lamps. Here I very slightly disagree with Steve, the broken fitting for the tungsten lamp actually occurred during the central column's first refit for Pyramids of Mars (N.B., Pyramids and Planet of Evil were recorded in the opposite order to which they were transmitted):



This also goes someway to explaining the subsequent absence of the metal joining pieces in the column's outer cylinder from this point in time onwards - it would appear that in repairing the fitting for the tungsten lamps, the outer cylinder was damaged and had therefore to be replaced. (The repair to the lamps' fitting however doesn't seem to have been very durable and - as Steve pointed out - the repair subsequently failed and the lamps again worked loose.)

The working loose of the tungsten filament lamps is also useful in determining the construction technique used by Kenneth Sharp's team in January 1971. Looking at the screen grab of the central column immediately above, it can be seen that both lamps are leaning at the same angle i.e., that the two lamps are joined (and not just by the little circular sheaves) by something which holds both lamps in a straight line; if this were not the case, we'd expect to see a 'dog leg' or kink where the two lamps meet inside the middle sheaf. So, the two lamps are being held together in a straight line by something which is not easily visible.

I used this screen grab before to identify the joining strips on the black circular base but it also shows that the central column was actually fairly robustly constructed - it's been leaned on its side, so all the weight is resting on relatively thin pieces of plastic. Look carefully where the top armulets join the lamp fittings - there is something there which runs down the entire length of the filament lamps holding them in place:



Whilst obscured by the green shafts, this 'supporting strip' is also visible in these screen grabs and would appear to be a continuation of the vertical pieces attached to each of the 'armulets' at the top of the column:





So, it looks like a one inch wide piece of Perspex (some 20" tall) was attached to each of the armulets and this in turn was attached to each of the sheaves which link the tungsten filament lamps.

We mentioned the Perspex from which the central column was constructed and the widths of the various pieces. Let's return to this (rather sad) picture of the battered column in its final days:



The minimum thickness in which Perspex is now commercially available is 3mm (0.125"). It is possible to heat form and roll Perspex into thinner pieces - up to Christmas 2013 we had a machine at work which was capable of doing this (in essence it looked rather like an old-fashioned mangle (which used to come with washing machines) and worked by rolling/squeezing/heating the Perspex into thinner panels). This machine was over 25 years old when it was eventually de-commissioned; it is entirely possible that the BBC also had one of these machines.

The reason I suggested that the outer cylinder was made of Perspex is because it has been broken - there is a sizeable chunk missing from the rear top-side of the cylinder. By comparing the thicknesses of the cylinder with - say - the yellow strips, we can see that it is thinner. Now, if we take the yellow strips as being made from the standard 1/8th inch (3mm) thickness Perspex, then the column's thickness is considerably less - approximately 1.5mm or 1/16th inch (it may even be thinner than this). So, if the outer cylinder was made from Perspex, then this Perspex has been thermo-formed/rolled into a thinner sheet than would be commercially available.

It is of course entirely possible that another material was used to construct the cylinder, perhaps polycarbonate (which is available in 0.75mm thicknesses upwards). However polycarbonate is notoriously difficult to shatter (riot shields are made of it) - it will crease rather than break. So, whatever the outer column was made from, it was brittle (or, at least, became brittle) which is suggestive of Perspex. Steve has suggested acetate as an alternative material for the outer cylinder's construction. I'm only familiar with acetate as very, very thin sheets (the kind of thing used in coloured lighting 'gels') but if acetate was/is available in greater thicknesses, then it is entirely possible that this was the material that was used.

Anyway, after that little summation of the last fortnight's posts, on to the 'meat' of this thread - some more dimensions!

As we've seen from what came before and after (i.e., the Hartnell and Mike Kelt versions of the console), the column's diameter in these versions of the console was 22"; the drawing by Peter Logan (who worked on both Inferno and Claws of Axos) also states the dimensions for the console's collar (34" across). Taking these factors into consideration and also by reference to the ratios of the diameter of the hole in the collar, the diameter of the column's outer cylinder and the diameter of the column's black base, we established the following formula (you may remember, I posted two photos; one from The Pirate planet and one from Claws of Axos which highlighted the apparent discrepancy in the sizes of the black circular bases between the two adventures - the apparent discrepancy being due to the three joining strips on the base which serve to increase the apparent diameter because of the angle from which we're viewing it):




For Pirate Planet:-
Where 760 pixels = 100 units,
the diameter of the Perspex cylinder = 700/760 x 100 = 92.105 units and
the diameter of the black base = 570/760 x 100 = 75 units.

For Claws of Axos:-
Where 476 pixels = 100 units,
the diameter of The Perspex cylinder = 438/476 = 92.017 units and
the diameter of the black base = 352/476 = 73.950 units.

Courtesy of Peter Logan, we can now establish the diameter of the hole through which the column rises and falls - our 100 units = 24 inches.

For Pirate Planet:-
Where 760 pixels = 100 units (24"),
the diameter of the Perspex cylinder = 700/760 x 24 = 22.1"
the diameter of the black base = 570/760 x 24 = 18" (INCLUDING THE JOINING STRIPS).

For Claws of Axos:-
Where 476 pixels = 100 units (24"),
the diameter of The Perspex cylinder = 438/476 x 24 = 22.08" and
the diameter of the black base = 352/476 x 24 = 17.75" (EXCLUDING THE THREE JOINING STRIPS).

In some ways, it's a pity that Karsthotep chose to call  http://tardisbuilders.com/index.php?topic=3507.0 the 'definitive' set of measurements for the Pertwee/Baker/Davison central column. Without wishing to cause any offence, (which is definitely not my intention), all the dimensions posted in that thread are predicated on the diameter of the black base as being 18". As I hope to have shown, the ratios from the screen-grabs immediately above demonstrate that this wasn't the case and the diameter was a quarter of an inch smaller than thought when http://tardisbuilders.com/index.php?topic=3507.0 was created.

As well as altering our understanding of the dimensions, the revelation that the black base was smaller than previously thought, actually reveals a surprising and pleasing geometric shape to the column's construction: Each tungsten filament lamp is spaced 8" apart and lies on a circle 4.62 inches in radius. Furthermore, the inclusion of the angled multi-coloured panels emphasises this pleasing geometry even further - resulting in a hexagon which mirrors the shape of the Console itself; the hexagon so formed has sides measuring 4.62" each:




(Note the use of clear hexagonal rods to support the angled panels.)

The overall height of the structure can - in part - be established by reference to the lengths of the tungsten filament lamps. Again, thanks are due to Steve for providing the following dimensions taken from a 'real life' filament lamp:



Further 'proof' of the assembly's height can be derived from the diameters of the three green 'shafts' which surround these lamps (4"). By comparing the sizes of these elements, the height of the internal column can be established as 20" from the top of the mirrored disc to the top of the three shafts (the armulets add a further 0.25" to this figure):



In addition, by comparing the widths of the multi-coloured panels to the known diameters of the filament lamps, we can establish these dimensions as well. The vertical spacings of these panels can be established by reference to various screen grabs:



T

[karsthotep]

My mind is blown here, Wow you guys have put together a comprehensive thread on the console and the time rotor.  I am in awe and this is going to help immensely with other members builds, mine included.  I have to give Kudo's to all contributers here.  I love it.  The construction diagrams are amazing. 

[tony farrell]

We aim to please.  

As a little bonus to those interested, this is an overhead diagram of the central column in metric dimensions (adjusted to allow for the fact that 4" diameter Perspex 'shafts' are no longer commercially available (the nearest equivalent size is 100mm compared to the exact imperial equivalent of 101.6mm)):



And, if you download this picture and print it at 2000 pixels by 2000 pixels, you will have a full-sized version:



T