Daft PACE question of the day

[JeRkY]

I was always under the impression that pace made their frames from box sections to because they had worked out that it was better for the loads/forces being placed upon the frames. If you look at the down tube, it is deeper than wide, making it stiff has hell over bumps (oo-er).

Round tubes flex in any direction, so making for a more comfortable ride.

But then again, i'm probably way off the mark....

Pretty much what I said. And as for being limited by materials, if that was the sole consideration the frames would of been round section too...also as suggested.

 

[tangent]

Not an engineering answer at all....but am pretty sure Duncan / Adrian choose to use square section frames it was easier for them to build with / align whilst fabricating in their chosen frame material aluminium. I think they say as much in an interview somwher BITD.

The forks legs, being made of steel, were round tubes -- cos that was the most suitable material to use in that application. It was the 'composite' (steel bolted into machined aluminum crown like K.B) nature of their forks + steerer stem solution was innovative / radical part...

Does quite answer the hypothetical question...but I think it does boil down to making choices about materials etc.

 

[lewism]

Right, this is my best educated guess (I studied Mechanical Engineering at one of the 'Great Universities' mentioned in Blackadder IV, but it didn't begin with an 'O' or a 'C'). On a beam being bent, the stresses are concentrated on the outer surfaces of the beam in the plane of being bent. That's how I beams work - the material in the middle isn't really needed so it's omitted, the central web is mainly there to link the two outer surfaces together. That's why Pace could machine away the material on the sides - it wasn't really needed to maintain the structural integrity of the frame. A fork operates mainly in compression, working differently to the beams in the frame. A circular section would work better here as it minimises the volume (and hence weight) of material used (look up Euler's formula, if you REALLY want to know about this / are having trouble sleeping), a square section would use more material. It's also worth bearing in mind that these frames were designed before 3D CAD modelling and Finite Element Analysis (a method of analysing the stresses in an object on a computer, I used it as part of my final year project to reduce the weight of industrial seed presses for a company by about a third) were widely available, certainly to a small company. All this being said, I think we're ignoring coolness - which is not really quantifiable in engineering terms. The Pace frame was designed as their big product, the forks were available as an aftermarket upgrade to everyone. The Pace frame is undeniably a work of beauty (if anyone's bored of theirs, send it my way by the way), and let's face it that counts for a hell of a lot.

Feel free to take anything I've said with a hefty pinch of salt though - I now work in the food industry, got sick of working for engineering companies that never made any money! If only we made stuff in this country nowadays, including Pace.

 

[matt.bee]

Sure I read an interview back in the day where they said they used square tubing as they could align it by using a flat surface, rather than having a much more complicated jig. It then became their point of difference, and as usual with these sort of things the mtb press managed to find other justifications as the real answer just isn't sexy enough.

 

[JeRkY]

Sure I read an interview back in the day where they said they used square tubing as they could align it by using a flat surface, rather than having a much more complicated jig. It then became their point of difference, and as usual with these sort of things the mtb press managed to find other justifications as the real answer just isn't sexy enough.

I think that was a fairly tongue in cheek comment at the time. Probably grounded in a side effect of using square tubing but none the less tongue in cheek.

 

[MikeD]

They wanted to make everything themselves, as far as reasonably possible. And they wanted to use aluminium. At the time there weren't any off-the-shelf butted aluminium tubesets, so the only option to shave some weight off was to machine tubes down. Which is eleventy million times easier with a square tube.

And the alignment thing

 

[ratcapa]

Their frame tubing all came from Spondon motorcycle's in Derby. If you have a paceI think up to 99 and its damaged apparently Spondon may be able to repair it for you as they still use the same tubing for their builds.

Sorry if this has already been said but I didn't read the whole thread word for word.

They were also pushing the envelope of design like yates, Roberts etc BITD but prob wanted to be different and stand out yet still make exceedingly good bikes.... Which they did.

 

[rc300]

http://maps.google.com/local_url?q=http ... cgAhyIFwhQ

9 miles from my house... incase any of mine do break