Suspect thread form of threaded rod

[Bill PhinnParticipant @billphinn90025]

I’d be interested to have people’s thoughts on the way the thread has been rolled/cut on the lower example of commercially available threaded rod in each photo. The BZP pair are M10, the self colour ones 1/4″ BSW.

My view is that the threads on the top samples in each case are correctly cut, and on the bottom examples the flank angles are much too steep, and this has resulted in threads that are significantly weakened, especially in the case of the M10 sample.

Would you want to use threaded rod in this condition for any significant load bearing purpose?

 

[bernard towersParticipant @bernardtowers37738]

Let me guess where they came from

[FulmenParticipant @fulmen]

Wow. Looks almost trapezoidal.

[DiogenesParticipant @diogenes]

They’re pretty horrible – unusual to get ‘cut’ threads in commercial (mass-produced) studding; were they both from the same supplier?

[Bill PhinnParticipant @billphinn90025]

Thanks for the replies.

The M10 was from Toolstation, the BSW from Cromwell.

I expected better of Cromwell.

There are a few negative reviews of Toolstation’s offerings, e.g.:

“I don’t understand why this product has so many 5* reviews, it’s awful. I hadn’t looked at the product closely before cutting to length to use it. Once in place I applied around 20 foot pounds of torque and the thread stripped. Looking at the thread, instead of a 60° thread profile, it’s around 90° and about as thin as a razor blade. No strength at all in this product. DO NOT BUY if you need a quality product.”

I feel compelled to ask: what is going wrong in the manufacturing process?

[Nigel Graham 2Participant @nigelgraham2]

Studding sold by shops like Toolstation is probably assumed to be for building work, such as holding electrical cable-troughs and the like, where high loads and frequent dismantling and re-assembling is not expected – not high-quality mechanical engineering.

Even so those examples, especially the M10,  are very poorly made: badly-set rolling machine perhaps? Or even badly-made tooling! Certainly poor quality control.

[Beardy MikeParticipant @beardymike]

I’ve had similar studding from Screwfix/Toolstation in the past – I did no measuring, but it did look/feel like the threads were too sharp/narrow. I’ve used it for various noncritical things like holding vices to benches etc and never had a thread strip. Not sure I’d trust it for something safety critical though…

[Howard LewisParticipant @howardlewis46836]

The Toolstation studding looks a bit rough in one example, and far too thin in the flanks in the other.

Off my list of possible suppliers.

Actually, surprised that the therads were cut; would have expected them to be rolled in high volume production.

Moral, inspect carefully before accepting. (Was once offered a broken item by Toolstation, had to return next day to collect an intact one!).

Caveat emptor!

Howard

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