Myth test1 productsAdhesives, Glue & Tape
Epoxy: The Test Results
A head-to-head test of 1 epoxy options with the measured results for each. See how they ranked and watch the full test video.
Ranked first
JB Weld Original
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The measured results
Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.
| Product | Material Used | Cure Time | Construction | Durability Test |
|---|---|---|---|---|
| 1JB Weld Original | 4 large-size tubes of JB Weld, roughly 24 oz total, used to build an entire cylinder head about an inch thick | cured for about a week before testing (JB Weld itself calls for about 24 hours to cure; the narrator gave it extra time to be sure it was fully cured) | traced from the original head gasket for the outline, sanded flat against a leveled aluminum reference, bolt holes drilled using the original cylinder head as a drilling guide, valve clearance carved out with a Dremel, and a spark plug hole drilled and tapped with a tap and die set; a longer spark plug plus an extra washer were used to get the correct combustion-chamber depth | installed on a small engine and run for at least one minute without the JB Weld head coming apart, despite the narrator's own low confidence going in (he wore a full face mask in case it failed) |
How it was tested
- run a small engine with a fully JB Weld cylinder head (replacing the stock metal head) to see whether it holds up to the engine's heat and compression for a short run
Data notes and caveats
Single-product myth-test/stunt build (not a brand comparison), so winner/runnerUp/budgetPick are all null by design. No compression or temperature readings are given anywhere in the transcript; success is judged purely qualitatively (the head held together for at least a minute of running).