Which Thread Repair Kit Brand Wins?
This head-to-head test of 8 thread repair kit options has the measured results for each. See how they ranked and watch the full test video.
E-Z LOK
Price shown in test: $60
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The measured results
Every number below is read straight from the test. Products are listed in the order they finished.
Max Torque Three Trials
- 1E-Z LOK706
712, 717 in lbs, bolt broke before the repair failed on all three, very consistent results, highest torque numbers of any product tested
- 2HHIP576
507, 500 in lbs, bolt broke before the repair failed on all three, stronger than the original 300-350 in lb aluminum baseline
- 3TIME-SERT571
492, 461 in lbs, bolt broke before the repair failed on all three
- 4Heli Coil493
483, 442 in lbs, bolt broke before the repair failed on all three
- 5JB Weld ProSize148
372, 98 in lbs, results varied quite a bit, averaged 206 in lbs before the repaired threads let go
- 6Loctite Red Threadlocker 271138
185, 97 in lbs, quite a bit of variance
- 7Loctite PC 3967 Stripped Thread Repair Epoxy139
83, 177 in lbs, threads stripped out on all three test pieces
- 8Copper Wire0
72, 0 in lbs, did not work out well on two of three test pieces
Hydraulic Failure Load Three Trials
- 1E-Z LOK1,000 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
- 2HHIP1,000
950, 1,050 PSI, bolt broke/stretched before the repair failed on all three
- 3TIME-SERT1,100
1,075, 1,025 PSI, bolt broke/launched before the repair failed on all three
- 4Heli Coil1,175
1,025, 1,000 PSI, bolt broke before the repair failed on all three
- 5JB Weld ProSize160
425, 160 PSI, averaged 248 PSI, the best average of the non-insert repair options
- 6Loctite Red Threadlocker 271150
140, about 130 PSI, fairly consistent, averaged well below JB Weld and the insert kits
- 7Loctite PC 3967 Stripped Thread Repair Epoxy160
110, 75 PSI, about 115 PSI on average, weakest of the epoxy/adhesive style repairs under hydraulic load
- 8Copper Wire0
near 0, near 0 PSI, failed immediately on all three test pieces
Corrosion Resistance
- 1E-Z LOK
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
- 2HHIP
second best of the insert kits, only a small amount of corrosion after 24 hours
- 3TIME-SERT
a little bit more corrosion than Heli Coil and HHIP, about the same as E-Z LOK
- 4Heli Coil
best of any brand tested, no visible signs of corrosion after 24 hours
- 5JB Weld ProSize
not tested (corrosion test limited to the four metal insert kits: Heli Coil, HHIP, E-Z LOK, TIME-SERT)
- 6Loctite Red Threadlocker 271
not tested (corrosion test limited to the four metal insert kits)
- 7Loctite PC 3967 Stripped Thread Repair Epoxy
not tested (corrosion test limited to the four metal insert kits)
- 8Copper Wire
not tested (corrosion test limited to the four metal insert kits)
Insert Diameter
- 1E-Z LOK
by far the largest diameter of the insert kits, almost 12 mm
- 2HHIP
not stated in the transcript
- 3TIME-SERT9.47 mm
slightly smaller than Heli Coil's roughly 10 mm
- 4Heli Coilaround10 mm
may stretch slightly when inserted
- 5JB Weld ProSizenot tested
- 6Loctite Red Threadlocker 271not tested
- 7Loctite PC 3967 Stripped Thread Repair Epoxynot tested
- 8Copper Wirenot 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
