The “square extractor” is the ultimate weapon for broken bolts. The final solution to avoid failures with reverse taps

I don’t use anything else besides the “square extractor”…
It’s easy to use, and
the “grip strength can be set as needed” plus “strong grip” is its charm.

Not satisfied with reverse tap extractors? I highly recommend this item for you (*´ω｀*)

Conclusion of this article

• Recommended tool: KOTO (Koto Sangyo) Square Extractor
• Why square?:
  • Unlike spiral (reverse tap), it’s hammered in to bite, so it grips firmly without slipping.
  • Since the expanding force is weak, the risk of further tightening the bolt is low.
• Tips for success:
  • Drill the pilot hole **”as large as possible”** (to ensure the rigidity of the extractor).
  • Use a drill guide to drill the hole as centered as possible.

Whoa! The bolt broke~

I’m not surprised when a bolt breaks… it’s just a hassle.
With something thick like M8, my stress level is minimal

(‘Д’)

“Differences from reverse taps (screw extractors)”

Holds with up to 8 corners! The shape is also tapered.
The grip strength can be set as desired. *Depends on how hard you hammer it in.

Even if it breaks, bends, or twistsyou can still use the remaining part by sharpening it

Plus the price is so gentle~ affordable~ (*´ω｀*)whee

I keep collecting them without throwing them away

You can see I’ve only used thin to medium-sized ones.
We typically only encounter broken bolts up to about M4-8mm here.

Drilling the hole is the most important. Being careless leads to disaster

Making a “drill guide” that doesn’t wobble too much gives peace of mind.

Even with a guide, thin drills don’t always go straight.
But with a guide, accuracy is definitely better than eyeballing it, and the risk of failure decreases.

Taking your time is what matters (*´ω｀*)

After drilling, just hammer it in and turn it.

The larger the pilot hole diameter, the better. With a larger hole diameter, you can use a thicker extractor.
The square extractor won’t twist or break.
If it gets too small and thin, “it breaks” *I’ve experienced this

With a thicker one, the “solid grip” is incredible.

Even with a guide, it’s never perfectly centered, so “drill with some margin” is best.
This time, an M8 bolt broke.
I judged it to be slightly off-center, so I drilled a 5mm hole and removed it.

“Tips for drilling pilot holes: The importance of a drill guide”

Our shop doesn’t get many severely old bikes, so our experience with bolt removal is limited.
When you make something like this, labeling it is useful in case the same situation happens again.

“First tools, second tools. With the right tools, anyone can do it.”
What do you think?
Having a set of square extractors on hand “Oh!” moments will be a lifesaver.