Fabricating a Deck Lid Latch & Mounting Bracket.
By Jim Clark (The Hot Rod MD)
Building a hot rod requires the design and fabrication of many different components. Some of those components must be created from specific types of materials and be strong enough to perform in a safe and reliable manner. Others just perform a basic function and present no particular safety hazard should they fail. A latch for holding the deck lid in place fits into the latter category.
If it malfunctions while you are driving down the highway the worst that will happen would be damage to the paint as the deck lid flopped around or loss of some of your stuff if it fell out. However, the proper fabrication of a minor item like this can add to the enjoyment of the finished vehicle.
Early deck lid latches usually were mounted into the lid with a handle protruding through to the outside. They had a lock cylinder incorporated into the handle and latched / unlatched by turning the handle to engage or disengage a slotted arm. The arm grabbed onto a round rod or stamped sheetmetal latch bar. They worked “ok” but most rod builders smooth the deck and get rid of exterior handles.
Changing to an internally actuated latch is now pretty easy because there are a number of latches offered by the aftermarket hot rod suppliers and a lot of donor car latches to choose from in wrecking yards.
Shown here are some of the latches that you could purchase and
how a bracket was fabricated to mount a deck lid latch from a donor car.
Rocky Hinge: Bottom-Mount Trunk Latch. Comes complete with mounting bolts.
This latch is one of the simplest to install on many of the early model cars.
Has positive latching feature like so-call “bear-claw” door latches
. May require a stronger solenoid than the ones supplied in the inexpensive
kits offer by some suppliers.
Rocky Hinge: Side-Mount Trunk Latch Comes complete with mounting bolts.
Same features as the bottom-mount latch but with holes for face-mounting the latch.
This installation on Pat Ganahl’s ’32 roadster is a good example of how the
bottom-mount latch can be installed. Assembly resides completely
below the rear threshold of the trunk opening
Rocky Hinge: Flush-Mount Trunk Latch
Flush- mount trunk latch is cable release ready & measures 2-3/8" x 3-5/16" wide
. The spring-loaded striker pin measures 2-3/4" long. Comes complete with mounting
hardware. Might work better on some later model vehicles
SPAL: 40 lbs Solenoid w/Hardware
Replacement Solenoid: This solenoid has over 40 pounds of force and a
small mounting size that make them ideal for early street rods with
small doors, antique vehicles and many others.
SPAL: DP-3 Door Popper
The DP-3 door popper features aluminum and stainless steel construction and
is set for a flush or surface mount. The tips of the poppers can
be cut down to give you the desired amount of "push"
without sacrificing your doors or the cars around yo
Ron Francis Power Trunk Wiring: Instructions for installation of Color-Coded,
Pre-printed Feed Wires The power trunk is wired into a battery source (hot all the time).
This allows the control of the trunk solenoid/motor without having to turn the ignition
switch on. Note: This accessory should be connected to a momentary type
switch only, failure to do so could cause damage to the trunk solenoid/motor.
If you are not using one of our panels connect the power trunk feed wire
to a source that supplies voltage (12 volts) all the time (key on or off).
The other wire (SWITCH->TRUNK) runs from the switch to the trunk solenoid/motor
. The power trunk solenoid/motor must be grounded.
Ron Francis Water-Proof Push Button Switch
Great for electric latches. Weatherproof for use underneath the
vehicle for door or trunk releases. Requires a 5/8" mounting hole.
Watson's StreetWorks: Billet Knob Cable Release
A straightforward, attractive machined billet knob with a 120" cable so you can
open your hood or deck lid. Top quality aircraft cable and durable housing may be
cut-to-length. Kit includes housing end cap, "no-fray" cable stop and 3 cable clamps.
SPEEDWAY MOTORS: ELECTRIC TRUNK RELEASE KIT
Enough 12-volt solenoids, switches, relays and wire with hardware necessary
to activate one latch with one switch.
Hotronics Products offers a wide range of Actuators and other electronic
parts that could be used in a trunk latch application
This release cable is the type commonly used to operate the tilt mechanism on car seats
. S-shaped hook on the end and housing mount make attachment at the latch simple.
Lever on this cable allows a flush mount into a panel for the trunk latch release. Might be
better than a pull-type cable in some applications
Early-style latches usually featured a bar that rotated to latch or unlatch mechanism.
This early Ford latch is shown with the bar in the unlatched position.
View of latch from backside shows the bar in the latched position and the small
spring that guided the bar from latched to unlatched position.
Latch mounted flush into the deck lid and was operated with the locking handle that
protruded through the face of the deck lid.
The latching bar on early-style latches was usually just a stamped piece of sheetmetal riveted to the trunk rail.
Many small import and domestic model cars have trunk latch assemblies that can be easily adapted
. Assembly on the left is from a Datsun 510 from the early ‘70s. Assembly on the right i
s from an early model Corolla
The Datsun 510 latch is the one that I chose to adapt to my ’32 roadster. The angle of offset in the mounting |
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A pattern for the latch was made and transferred to the latch |
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Latch operating lever protrudes through the hole in the bracket. Hacksaw cut was made halfway through |
Heat was applied to the backside of the hacksaw cut and the bracket bent to match the angle on the latch. Hole was enlarged to allow latching lever to move through its full range of motion. |
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With the latch in place on the bracket, mounting holes are marked, drilled and tapped for the 1/4-20 bolts holding it. Edges are then ground to match the contours of the latch |
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Bracket was then trimmed to the proper depth for installation inside the rear of the roadster threshold panel. |
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Hacksaw cuts in the backside of the bracket were filled using an arc-welder, then ground flush. |
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Threshold on the deck is angled forward 20-degrees from level. I needed to find the correct angle to grind on the bracket so that it would be perpendicular. |
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Threshold panel does not form a 90-degree angle at the mounting surface so I hade to measure it with this angle-finder (60-degrees) and add the opposite angle (20-degrees) to come up with the angle to be ground on the bracket face. |
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This photo of the bracket shows the 10-degree angle that I had to grind on the bracket to achieve a perpendicular mounting. I did it with a grinder and files; a milling machine would make the process easier and more precise. |
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A slot had to be cut for the latch to protrude through. It was spaced in 1/4-inch to allow for the thickness of the mounting bracket. Marker was used to indicate the cut lines. |
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Holes were drilled at the end of the cutout to serve as starting points for a saw or the cutoff tool that was used |
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We used an air-powered cutoff tool to cut both sides of the slot. Jigsaw would also work if that is all you have. |
Cutting of hole was completed with a small hacksaw designed to hold a blade for this type application |
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File is used to finish shaping the opening. Better to make the opening a little undersized and fine-tune it later. |
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Latch was test-fit in the opening to determine the amount that it was to protrude through the opening. Measurements were marked on the rear mounting face and marked for location of the mounting holes. |
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Holes were drilled to accommodate mounting of the latch |
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Latch is held in place by wide based bolts that spread the load on the surface of the sheetmetal similar to that of a flat washer. Small ridges in mating face act like lock washers, without digging into the sheetmetal. |
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This is the finished latch shown in the unlatched position. |
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Latch shown in the latched position. Bottom of opening had to be positioned above the line of the threshold so that the bar mounted on the deck lid could be fully engaged. |
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View from below shows how the bracket bolted to the panel and allowed the actuating lever to have clearance for latching and unlatching. Cable or solenoid power will attach here. |
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Striker bar half of the latch mechanism attaches to the underside of the deck lid. Mounting holes in the deck lid striker bar can be slotted to allow for any fine-tuning of the engagement between the two pieces. |
A latch assembly from a donor car will work fine for most early car applications. Buying one from an aftermarket hot rod parts supplier is also a good alternative. Either one will require the fabrication of some kind of mounting bracket and the cutting of access for it. A release cable or electric-powered solenoid kit can be used to actuate the latch mechanism. Techniques used in this project would be similar to those used to fabricate many other types of brackets in the process of building a hot rod.