Snapped spindle

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silva

Über Member
Location
Belgium
Another cheeky and lazy question: any idea what the equivalent calc for a solid square taper is?
The same one: there is a dropdown box selecting hollow or solid.
The solid choice sets the inner diameter to zero.
Wonderbar Wonderbar from Rammstein. ;)
 
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silva

Über Member
Location
Belgium
And, Mister roubaixtuesday
Not yet calculated what you asked for?
Square taper is documented as 17 mm axle diameter.
The axle length can be chosen with 1-2 mm resolution as to get a chainline correct.
(I learnt this after discovering 8 years later when frame broke, that my avatar bike was originally delivered with a 5 mm too long axle, causing chainline front 5 mm more than back, causing chain Dancing The Twist until I discovered it, and abnormal proneness to pedal strikes during entire frame life).
In the Cheating Light Religion Church the bottom bracket can be Stuffed Up by spacers towards the correct chainline.
But as said in previous post, it's about the difference and parameters like axle length and wall thickness are the same on both sides of the comparison so can be eliminated.

Also, for what it matters, since the subject of the discussion was better resistence to snapping, by increasing the wall thickness of the HollowTechnology2 shaft, that is, a smaller inner diameter.
As calculations showed: a 50% increase in wall thickness, for ex 2 to 3 mm, 1 to 1.5 mm, ... results in the shaft becoming 29% better withstanding torsion force.

That's like a bridge over troubled water that has its capacity to users flagged as "40 tonnes max", that has a reserve of 11.6 tonnes more, so actually 51.6 tonnes.
So if for whatever reason some damage occurs, and/or for whatever reason some overload occurs, there is the 11.6 tonnes reserve to avoid falling in troubled water, or in your case, avoid Luckily just 3 Miles Limping on 1 Leg back home.
You then wouldn't have had the Limping story, and wouldn't have had the replacement cost and work.
The Big Drawback of that Safety Plus: 20 grammes, or make it 40, 80, ... 1 second more per mile, due to the presence of about half an apple in your pocket.
Fine to win a fitness race by cheating, but to commute, shop, well, 20 grammes is the weight of a credit card. Some people have 10 of those in their wallet. At the cashier they then spent 5 minutes search and try to, alike the HollowTech2 chainline story, stuff together the ticket price.
The next customer then pays cash and passes in 20 grammes err I mean seconds.

Btw, how many credit cards do you have? ;)
 
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roubaixtuesday

self serving virtue signaller
And, Mister roubaixtuesday
Not yet calculated what you asked for?
Square taper is documented as 17 mm axle diameter.
The axle length can be chosen with 1-2 mm resolution as to get a chainline correct.
(I learnt this after discovering 8 years later when frame broke, that my avatar bike was originally delivered with a 5 mm too long axle, causing chainline front 5 mm more than back, causing chain Dancing The Twist until I discovered it, and abnormal proneness to pedal strikes during entire frame life).
In the Cheating Light Religion Church the bottom bracket can be Stuffed Up by spacers towards the correct chainline.
But as said in previous post, it's about the difference and parameters like axle length and wall thickness are the same on both sides of the comparison so can be eliminated.

Also, for what it matters, since the subject of the discussion was better resistence to snapping, by increasing the wall thickness of the HollowTechnology2 shaft, that is, a smaller inner diameter.
As calculations showed: a 50% increase in wall thickness, for ex 2 to 3 mm, 1 to 1.5 mm, ... results in the shaft becoming 29% better withstanding torsion force.

That's like a bridge over troubled water that has its capacity to users flagged as "40 tonnes max", that has a reserve of 11.6 tonnes more, so actually 51.6 tonnes.
So if for whatever reason some damage occurs, and/or for whatever reason some overload occurs, there is the 11.6 tonnes reserve to avoid falling in troubled water, or in your case, avoid Luckily just 3 Miles Limping on 1 Leg back home.
You then wouldn't have had the Limping story, and wouldn't have had the replacement cost and work.
The Big Drawback of that Safety Plus: 20 grammes, or make it 40, 80, ... 1 second more per mile, due to the presence of about half an apple in your pocket.
Fine to win a fitness race by cheating, but to commute, shop, well, 20 grammes is the weight of a credit card. Some people have 10 of those in their wallet. At the cashier they then spent 5 minutes search and try to, alike the HollowTech2 chainline story, stuff together the ticket price.
The next customer then pays cash and passes in 20 grammes err I mean seconds.

Btw, how many credit cards do you have? ;)

Which species of duck do you think best aligns to your thoughts on square taper?

Or would you say a different diving bird better relates to your posts?

Perhaps a loon?

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Beautiful plumage.
 

classic33

Leg End Member
@silva, are you talking about credit/debit cards that are covered by the ISO/IEC 7810 ID-1 standard?
It dictates the size of the card, and materials, which means it also indirectly dictates their weight. Which for most is 5 grams, metal cards may be slightly heavier.

This standard also applies to ID cards, plastic driving licences and train/bus cards.
 

Ming the Merciless

There is no mercy
Location
Inside my skull
Another cheeky and lazy question: any idea what the equivalent calc for a solid square taper is?

Compared to modern "oversized" spindles (like Shimano's Hollowtech II or BB30), the square taper has a very small diameter. A larger diameter spindle is inherently stiffer. Under a world-class sprinter's load, a square taper spindle will encounter higher shear stress than a modern 24mm or 30mm spindle.
 

Dogtrousers

Lefty tighty. Get it righty.
Compared to modern "oversized" spindles (like Shimano's Hollowtech II or BB30), the square taper has a very small diameter. A larger diameter spindle is inherently stiffer. Under a world-class sprinter's load, a square taper spindle will encounter higher shear stress than a modern 24mm or 30mm spindle.

Also the wider spacing of the external bearings will be stiffer for the world class sprinter ... I think.

But that's really only a concern for mega performance cyclists. Not decrepit old fools like me.
 

Ming the Merciless

There is no mercy
Location
Inside my skull
Also the wider spacing of the external bearings will be stiffer for the world class sprinter ... I think.

But that's really only a concern for mega performance cyclists. Not decrepit old fools like me.

And of course @roubaixtuesday who would twist square taper to within an inch of its life before it snapped.
 
OP
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roubaixtuesday

self serving virtue signaller
Compared to modern "oversized" spindles (like Shimano's Hollowtech II or BB30), the square taper has a very small diameter. A larger diameter spindle is inherently stiffer. Under a world-class sprinter's load, a square taper spindle will encounter higher shear stress than a modern 24mm or 30mm spindle.

That was my assumption - that a square taper will fail under lower load than hollow tech, the solid spindle failing to compensate for the smaller diameter.
 
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