#009 Hurst Point Lighthouse

Building the wonderful Paper Shipwright model of the historic Hurst Point Lighthouse, and bringing it to life with a Fl(4) W 15s LED array.

Build

Here’s a quick demo..

Notes

I recently stumbled upon David Hathaway’s Paper Shipwright, offering a range of paper models of ships, lighthouses and other buildings. I had to buy a few (some are even available for free download if you have a suitable printer).

Hurst Point Lighthouse held special appeal for me, as I grew up in the area and spent many a day sailing this part of the Solent with my father.

The paper model is a 1:250 rendition of Hurst Point Lighthouse (Hampshire, UK). The current lighthouse dates from 1867 and was modernised and electrified in 1997.

Location: Hampshire, UK
Position: 50 42′. 44 N 01 32′.94 W
Height: 26m
Built: 1867
Light: Fl(4) WR 15s 14nm

kit

The Light

The lighthouse characteristics are recorded as “Fl(4) WR 15s 14nm”.

Translated, this means flashing 4 times every 15 seconds, visible to 14 nautical miles. “WR” I think means alternating white and red, but I’m not too sure and wasn’t able to find any clear confirmation. For the build, I’m going to simply do a flashing white light.

I decided to use a simple 555 timer circuit comprising two cascaded timers: the first provides the overall 15 second window with an on-period long enough to enable the second timer to perform 4 flashes at about 0.65 Hz.

Breadboard

Schematic

First testing the basic circuit on a breadboard:

HurstPointLighthouse_bb_build

Some circuit notes:

diode D2 is not required (I had it in circuit as originally I was using a smoothing RC circuit on the LEDs, but removed this in the final build as it wasnt adding much to the effect)
timing is not 100% accurate, as it is at the whim of component values and tolerances. But I have it close enough for my liking.
the first flash is a little longer than the following ones, as C5 must charge from fully discharged to 2/3 VCC and then oscillating between 1/3 and 2/3 VCC. There is probably a way to avoid this but I haven’t solved that problem yet.

Here’s a scope trace of the flashing sequence:

timing

The circuit was finally transferred to some protoboard before installation:

build_soldering protoboard_layout

I used three SMD white LEDs in a parallel radial array for installation in the model. Copper wire provides a solid mast making installation easier. A plastic sleeve and some aluminium foil complete the light fixture.

build_led_mast

Testing the LED mast on the breadboard:

build_led_mast_test

Building the Model

It’s quite an easy model to assemble, just requires a steady cutting hand and some patience. The fit of the parts was very good.

The support buildings:

build_buildings

I diverged from the paper model for the railing and light enclosure, fashioning these with some clear acrylic, cotton thread, and some component lead offcuts.

build_upper_tower