Seaweed & algae contain the full spectrum of organic (photo-synthetic) vitamins, all minerals and 78 natural ionic sea trace minerals, lipids, plant sterols, amino acids. Omega 3's and 6's, anti-oxidants, growth hormones, poly-phenols i.e. in short, it contains almost everything one needs to sustain life.
We recommend a Tap Wrench for tapping and driver tools. BIG-SERT OVERSIZED UNIVERSAL HEAD BOLT ENGINE BLOCK THREAD REPAIR Normally used when a helicoil or coil style insert has failed. 10 inserts of a 30mm length included in M11 & M12 kits.
If you're doing this job with a hand drill you should still use a square or other means to ensure you drill squarely. The correct drill size for a 1/4-20 helicoil is 17/64. Here I drilled both holes to proper size and depth. The thread inserts require a special tap called an STI tap. When drilled and tapped to the size specified for the repair, the installed thread repair will yield the stated size.