Quarter-twenty bolts were part of joining the added light-bar extrusion to the rack and attaching the lamp. Bolt length also became a recurring detail in the later camera-mount fabrication.
The rack used quarter-twenty hardware, while the added 2020 extrusion used M5 hardware. The button-head bolts were included in the supplies for the roof-equipment work.
The small connecting brackets needed bolts at both profiles. Their hole locations, nuts and washers were part of the same assembly decision.
Planning Bolt Length Alongside the Drilled Brackets
I attached the light-bar connectors with quarter-twenty bolts and both washer types.
I mounted the light bar with quarter-twenty bolts and flat washers.
During later camera-mount work I planned to buy shorter bolts instead of repeatedly shortening the ones I had.
Another small bracket and bolt arrangement during camera-mount fitting.Bolts and washers at the custom connectors on my roof-rack assembly.
My Takeaway from This Job
Bolt length remained part of the fitting work after the metal pieces were cut. The finished connectors look simple, but the diary records repeated attention to nut position, hardware length and access around the roof equipment.
Selecting the bolt length belonged with planning the bracket, rather than being left until final assembly.
Product Details And Van-Build Uses
Specification
Product Detail
Thread
1/4-20
Head
Rounded button
Drive
Internal hex
Quarter-twenty hardware is an inch-thread family, separate from the M5 screws in my smaller extrusion connections. Keep that thread label with the chosen length before pairing the screw with a nut or threaded part. In a van bracket drawing, include the button head on the exposed face and the driver space above it. The full fastener stack is a clearer repair reference than identifying a replacement only from the rounded head shape.
It identifies the 1/4-20 thread; head form, drive and length remain separate details.
Alternative products
Two Alternatives to Compare
The IMScrews option uses a bright stainless button head at one length. The iexcell assortment changes to taller socket heads and provides several lengths. Head profile and the choice of shank lengths are directly relevant to the fitting work recorded in my build.
These stainless-steel machine screws use a rounded button head and a hex-socket drive. Their quarter-twenty threads and three-quarter-inch shanks provide a short threaded-fastener format.
This stainless-steel assortment contains quarter-twenty socket-head cap screws in several lengths. The taller cylindrical heads provide a different shape from button-head screws.
