Stripped threads

What do yall do when you strip threads? It is a cheaper throw, so I figure ill just chunk it, learn, and move one. Curious if others have ever stripped a throw, and what you did after?

Ive never done that thankfully. Definitely learn and move on id say. Its very easy to avoid from my experience.

Hopefully it never happens again haha Id be super bummed if it happened to me.

What yoyo is it? And did you buy it from us? If you did I’d be happy to take a look at it for you. Most of the time stripped threads can be retapped with a thicker axle.

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No I didn’t get it here. We have good machinist where I work, maybe I could get one of them to tap it out for me. Like I said, it is a cheap throw so I will probably just chalk it up to a learning experience.

Yeah, might not be worth the trouble if it was cheap, but that’s up to you.

Loctite in the side where it’s stripped should get it

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Assuming its a m4 thread, I would tap it with a M4-STI tap (oversized tap for inserts) and install a free-running M4 helicoil insert.

That bad boy will be stronger than the original threads, and you can use the same size axle.

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I just stripped my FH1 so that it doesn’t tighten or loosen when I turn it… am I boned?

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Like others have said, your only realistic options are to tap to a larger diameter axle or use an axle insert. Or if it’s not stripped too bad, using a lot of thread tape could work. Threadlock, too.

Though I wonder if anyone has retapped a stripped yoyo half by welding/brazing and redrilling/tapping.

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@LinksLegionaire Wont work if it is 7075, unweldable.

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You professionals are overthinking it. All you need is a larger axle, an allen wrench (even a yoyo multi tool works most of the time), something to cut the axle to size (dremel or saw), and a little determination. With that you can successfully retap a stripped yoyo 90% of the time. No need for retapping tools or inserts. The existing hole centers the larger axle and it threads into aluminum pretty easily. I usually use a CLYW axle to retap m4 axles.

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Very interesting, just looked into it.

I work in an automotive R&D facility. We used to have a joining team that worked exclusively on laser-welding aluminum. I remember he requested some analysis of some 7xxx grades he welded. Let me see if I can find any pics.

7xxx (top) to 5xxx (bottom)

Same stackup but a lap weld.

For comparison here’s a weld of 6016. Much better penetration and much lower porosity.

But I’m derailing the thread…

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Super interesting images, thanks for sharing these

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Helicoil is the way to go, actually makes it stronger being a steel coil to replace the aluminum threads.

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I always thought that at least most types of series 7 Al weren’t very weld-able.

Seemingly so. I remember him having a lot of trouble with some welds, though he rarely mentioned which grades. It would make sense if they were 7xxx grade, though all his welds were with a remote laser on a robot arm.

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A cool fix is to drill out the old threads then press fit in a aluminum rod and tap that for a M4-0.7 axle. Afterward the rod can be cut into a hubstack post or matador spikes. Here was a stripped Project C I bought and fixed up.



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So, technically, your statement is true with exceptions…

7075 is primarily considered to be unweldable. But that refers specifically to structural components. The reason being is the downside to being so strong in its alloyed nature, it is unstable when subjected to intense heat. Welding processes create ‘micro-cracking’ in reaction to welding. The stresses created in the weldment and peripheral zones are subject to severe metal fatigue. Structural components, when subjected to various amounts vibration, torque, impact, high speed under load, can lead to catastrophic part/device failure.

But there are instances where 7075 can be welded. Molds used for plastic injection, etc, are often made from 7075 aluminum. These mold bodies are stationary and not subjected to the strains and stresses of load bearing parts. These molds are anywhere from 3 to 18 inches thick depending on specific purpose.

When testing out new molds, sometimes the first test parts come out kinda ‘funny’ because the mold half cavities may not index/align perfectly.

Because the mold halves are not considered ‘structural components, Tugsten Inert Gas weldingTig) can be used to build up the mold half that needs adjustment. Once the mold half is ‘beefed up’ sufficiently in the targeted area(s), it can then be re-machined to spec…

Possible micro-cracking presents no danger of reaching a failure threshold.

I am most certainly not a ‘Machinist’. But being a Structural welder and Fabricator, specializing in Aluminum(with about 50 years of practicing), has helped me figure out a thing or two, haha.

… That being said, for structural ‘things’ welding 7075 is programming it for component failure with no exact failure date. But parts can often fail amazingly a day or two before a Funeral.

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