Sunday, 13 April 2025

Lights - Part 2

To make me feel like I was actually making some progress with this build I decided to install the lights onto the car before fitting the body to the chassis (although it's taken me so long to write this blog update that the body is now on the car!).

I've gone with the classic Lucas P700-style headlights which I ordered from S&J Motors.  These come with a plastic headlamp bowl and retaining ring which also includes the adjusting screws to alter the headlamp beam alignment. 

The first task was to measure up and transfer some centre lines to the headlight openings and the front indicator positions.  This was not entirely straightforward as the molding lines on the AK body are not symmetrical!.  I measured lots of times to get this right.

I could then mark out the required hole positions for the headlight bowls.  I did this by marking the position of the larger holes which are needed for the bosses of the beam adjusting screws and drilling these first.  I could then sit the headlight bowl flush into the opening and mark and drill the positions of the mounting screws.  The holes for the indicators were opened up with a 32mm diameter hole drill.

Centrelines marked out

Holes drilled

The headlight bowls were then fixed in place using self-tapping screws and spire clips on the back face to hold them in place.  I oversized all the holes slightly to allow some wriggle room in the final positioning of the headlights.

The headlight unit is then fixed into the retaining ring and this can be reinstalled into the bowl.  

The headlight bowl is fixed in place...

...and the headlight unit installed.

The indicator units were also fixed in place using self-tapping screws and spire clips.  The final step was to install the headlight rims.  I bought a pair of "chrome on brass" rims from Car Builder Solutions as they are less prone to corrosion than chromed steel rims.  The rims have a slight lip on the back which hooks onto the headlight bowl and are then secured in place by a single screw under the rim.  Getting the alignment of the rim correct such that the fixing screw actually lined up with its hole in the headlamp bowl was a surprisingly fiddly exercise.  

Completed front headlights and indicators

Installing the rear indicator and rear light/brake light units was much the same process as the front indicators.  Although I did spend a lot of time measuring and measuring to ensure the lights would be evenly spaced within the mounting zone on the AK body.  Again this was not so easy due to the slight differences in the body molding on each side.

Measure several times!

Holes drilled once I was happy with the location

Rear lights completed!

The last job was to install the side indicator repeaters.  These units from Car Builder Solutions just need a 20mm diameter hole to be drilled.  The mounting grommet is then installed in the hole and the LED light is pushed into the grommet from the front which fixes the whole unit in place.

Mounting hole for side repeater

Mounting grommet placed into the mounting hole...

...and side repeater and trim ring pushed into the grommet.

It's a small thing but getting the lights installed has started to make the project look more like a car now and hopefully, it will motivate me to get moving on with the build!





Lights - Part 1

I have chosen the Lucas L488 style Indicators and Stop Lights for Project Snake as I preferred the flatter profile of the lens glass to the alternative domed style lens.

Lucas L488 Style Indicator

These were fitted as original equipment on many British cars in the 1960s and 1970s.  I bought my units from S&J Motors and they still appear to be as per those original units, even down to needing to use Lucas brass bullet connectors to connect the wiring!

The rubber backshell holds the lens glass and the chrome trim ring in place and protects the wiring connections.  There are three holes in the backshell for wires to pass through.  However, these holes were much larger than the diameter of wire that I was planning to use (20AWG thin wall insulation from Car Builder Solutions) so I decided to add some wiring pigtails from the bulb holder to a weatherproof connector and seal the wiring with heat-shrink to keep it watertight.

Disassembled Light Unit and a Lucas Brass Bullet Connector

Using a special tool, the Lucas brass bullet connectors are crimped onto the wire.  I wrapped the wires around the bulb holder a few times to allow the bulb holder to be pulled out from the backshell in the future should the need arise.  I passed all the wires through one of the holes in the backshell, the other two will be plugged with Tigerseal or similar to keep water out.

Bullet Connectors crimped onto wires

I used a short length of heat-shrink tubing around the wires as they exited the backshell.  I also used a small piece of adhesive-lined lined heat-shrink to seal around the exit from the backshell and the wires; the adhesive melts and forms a weather-tight seal around the wires.

A (hopefully) weather-tight seal as the wires exit the backshell

For the connector at the end of the wiring pigtail, I have gone with Deutsch DTM connectors.  These are one of the 'go-to' electrical connectors in the high performance automotive market and offer great reliability and ability to endure harsh environmental conditions.

They use a Size 20 solid-barrel contact which is rated to 7.5Amps and can accommodate 20-24AWG wire.  

Typical DTM connector parts - Size 20 pin and socket contacts

Contacts are crimped with a special tool - note the pairs of indentations around the base of the contact

The pins are then inserted into the rear of the connector body, passing through a silicon wire seal, until they click into place.  A wedge lock is then inserted into the front of the connector body, which holds the pins or sockets in place and prevents them from coming loose.

Again I used a short length of adhesive-lined heat-shrink around the end of the connector body to seal around the body and the wires to keep it all weather-tight.

Full set of indicators and weather-proofed wiring pigtails


Friday, 11 April 2025

Body Preparation - Part 3 - Holey Moley Batman!

Another task required before the body could be installed was to cut holes in the floor pan for the gear lever and for the fuel tank filler neck and access to the fuel gauge sender unit.

To locate the hole for the gear lever, I made up a jig from a couple of pieces of strip wood.  This was located in the body mounting holes in the chassis and then I fixed a laser level onto the jig and aligned it with the centre of the gear lever.

Wood and Laser Level Jig

I measured the distance from the laser level's edge to the gear lever's centre. I then aligned the jig into the body using the mounting holes in the body to locate it and measured the distance from the edge of the laser level to the top of the gearbox tunnel to find the centre of where the hole for the gear lever needed to be.  I then cut the hole for the gear level using a 120mm diameter hole saw.

Locating the centreline of the gear lever on the body

One gear lever hole added
 
For the hole in the boot floor, I made a template out of a piece of cardboard, which used the two body mounting holes in the rear chassis cross-member as a location reference.  I transferred the template to the body and marked out the hole location.  Again I cut out the hole using a 120mm diameter hole saw for the ends of the opening and a multi-tool to cut the edges of the opening.

Cardboard template for hole in boot floor...

...transferred to the body...

...hole position marked...

...and cut out.

The last thing I did before getting the body on for its first trial fit was to put some foam tape along the top of the chassis rails.  The AK build manual suggests running a large bead of sealant on top of the chassis to seal the body to the chassis.  Obviously, as I intend on removing the body again at some point, I did not want to carry out this step.  However, using sealant, even in the permanent case would make any future body removal very difficult so I have elected to substitute the sealant for some 5mm thick closed-cell foam tape.

Self-adhesive foam tape around the chassis rails

Now I just need a nice day and a few friends around to get the body on for the first time!