2022 test8 productsHand Tools
Which Thread Repair Kit Brand Wins?
A head-to-head test of 8 thread repair kit options with the measured results for each. See how they ranked and watch the full test video.
Ranked first
E-Z LOK
Price shown in test: $60
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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 | Max Torque Three Trials | Hydraulic Failure Load Three Trials | Corrosion Resistance | Insert Diameter |
|---|---|---|---|---|
| 1E-Z LOK$60 | 706, 712, 717 in lbs, bolt broke before the repair failed on all three, very consistent results, highest torque numbers of any product tested | 1,000 PSI, then '1,50 PSI' as captioned (likely a dropped-digit transcription of 1,050 PSI, kept verbatim and flagged), then 1,100 PSI; bolt broke before the repair failed on all three | a little bit more corrosion than Heli Coil and HHIP after 24 hours in the hydrogen peroxide/vinegar/salt mix, about the same as TIME-SERT | by far the largest diameter of the insert kits, almost 12 mm |
| 2HHIP$20 | 576, 507, 500 in lbs, bolt broke before the repair failed on all three, stronger than the original 300-350 in lb aluminum baseline | 1,000, 950, 1,050 PSI, bolt broke/stretched before the repair failed on all three | second best of the insert kits, only a small amount of corrosion after 24 hours | not stated in the transcript |
| 3TIME-SERT$100, the most expensive repair kit tested | 571, 492, 461 in lbs, bolt broke before the repair failed on all three | 1,100, 1,075, 1,025 PSI, bolt broke/launched before the repair failed on all three | a little bit more corrosion than Heli Coil and HHIP, about the same as E-Z LOK | 9.47 mm, slightly smaller than Heli Coil's roughly 10 mm |
| 4Heli Coil$25 | 493, 483, 442 in lbs, bolt broke before the repair failed on all three | 1,175, 1,025, 1,000 PSI, bolt broke before the repair failed on all three | best of any brand tested, no visible signs of corrosion after 24 hours | around 10 mm, may stretch slightly when inserted |
| 5JB Weld ProSize$14 for the ProSize container tested (regular JB Weld typically $5 to $6) | 148, 372, 98 in lbs, results varied quite a bit, averaged 206 in lbs before the repaired threads let go | 160, 425, 160 PSI, averaged 248 PSI, the best average of the non-insert repair options | not tested (corrosion test limited to the four metal insert kits: Heli Coil, HHIP, E-Z LOK, TIME-SERT) | not tested |
| 6Loctite Red Threadlocker 271$6.48 | 138, 185, 97 in lbs, quite a bit of variance | 150, 140, about 130 PSI, fairly consistent, averaged well below JB Weld and the insert kits | not tested (corrosion test limited to the four metal insert kits) | not tested |
| 7Loctite PC 3967 Stripped Thread Repair Epoxy | 139, 83, 177 in lbs, threads stripped out on all three test pieces | 160, 110, 75 PSI, about 115 PSI on average, weakest of the epoxy/adhesive style repairs under hydraulic load | not tested (corrosion test limited to the four metal insert kits) | not tested |
| 8Copper Wire | 0, 72, 0 in lbs, did not work out well on two of three test pieces | 0, near 0, near 0 PSI, failed immediately on all three test pieces | not tested (corrosion test limited to the four metal insert kits) | not tested |
How it was tested
- maximum torque to strip baseline (unrepaired) aluminum threads
- maximum torque load holding strength after repair (three trials per product)
- hydraulic ram failure load in PSI (three trials per product)
- 24-hour corrosion resistance test (hydrogen peroxide, vinegar, salt mix) for the four metal insert kits
- insert diameter size comparison for the four metal insert kits