# Quad Butting?



## Fluffbomb (Aug 14, 2004)

Been looking at some old Fat Chance stuff on the web (www.fatcogs) and came across the term 'quad butting'.

I've heard of:

single butting - tubing thicker at one end only
double butting - tubing with thinner wall in centre
triple butting - tubing with thinner wall in centre and different wall thicknesses at each end

But what is Quad butting? Is it even thinner in the middle?

Fluff


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## bulC (Mar 12, 2004)

*no*



Fluffbomb said:


> Been looking at some old Fat Chance stuff on the web (www.fatcogs) and came across the term quad butting.
> 
> Ive heard of:
> 
> ...


it just means the butted part transitions through two thicknesses on the way down to the thinner middle. so really don't mean nuthin'. marketing, quad's gotta be better than tripel.
well that's true here anyways, as my belgian triple homebrew comes in around 9 percent abv, and my belgian quad comes in around 12.


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## colker1 (Jan 6, 2004)

bulC said:


> it just means the butted part transitions through two thicknesses on the way down to the thinner middle. so really don't mean nuthin'. marketing, quad's gotta be better than tripel.
> well that's true here anyways, as my belgian triple homebrew comes in around 9 percent abv, and my belgian quad comes in around 12.


do late yo eddys altered their angles just slightly towards the 71/ 73 "norba" geometry (things get old quickly huh? where is norba these days in the grand marketing schem of things?)?


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## DeeEight (Jan 13, 2004)

The butt is the transition point between two thicknesses/dimensions of the structure (spoke wire, frame tube, whatever). So whatever the number, that's how many transition points there is and that's it. A double butted tube does not for example, have to be the same dimensions on the ends and thinner in the middle. It could transition from say a thick wall by the headtube, thinner in the middle, and then slightly thicker at the seattube but not as thick as near the headtube. 

Some companies have taken to mixing up the butts with the actual dimension variations. For example, some bike catalogs/online stores call the DT Alpine III spokes triple butted for example, even though there are actually only 2 butts to the spokes. There are three different thicknesses of spoke (2.34mm at the head, 1.8mm mid-span, and 2.0mm at the nipple) but only 2 butt zones. DT probably lends to the confusion a bit as they describe them as triple forged, but still, they're just double-butted spokes still. 

Quad butted frame tubing means there's 4 butt zones, but doesn't help you determine how thick the tubewall is in different areas. Giant's last big hooraw into steel frames in the late 90s was to draw their own quad-butted heat-treated 4130 chromoly tubing in their own steel foundry, in order to make a 3.5 pound (18") steel hardtail frame for their ATX 8xx series frames. Problem was, they were spec'ing them the same as some of their aluminium frames, and for the same price, and well, consumers wanted aluminium instead, even though those frames weighed more. So they were poor selling models and were dropped after a couple years.


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## Fluffbomb (Aug 14, 2004)

*Confused!*

Now I'm started to get confused!

I read on a page (a reputable one but I can't remember which one) that the double & triple butting was as I stated at the start but having looked at a couple of tube specifications I've come across different interpretations.

Easton have a tube with different wall thicknesses at each end and a thinner walled central section which they describe as double butted (in agreement with DeeEights statement above).

and then,

Columbus & Dedacciai have tubes with equal wall thickness at end end and a thinner walled central section that they call triple butted (different to how both DeeEight and I interpreted tube butting).

Fluff


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## Fluffbomb (Aug 14, 2004)

*Oh and ...*

Why would you change the wall thickness in the centre of the tube? Once you butt (or taper) the tube wall from around the joints is there any change in the loadings seen by the centre of the tubing that allows you to further thin the central sections wall thickness? I've looked at tubing from Easton, Columbus, Dedacciai, Reynolds & True Temper in Steel & Alu and haven't come across any that have a further thining in the centre most part of the tube!

Fluff


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## Fluffbomb (Aug 14, 2004)

*Butting*

I had the following from Reynolds re tube butting.



> double butted is usually used by Reynolds when the tubes are thicker at
> each end.
> 
> So a double butted tube .9/.6/.9mm 100.50.300.50.100mm would have 100mm
> ...


Fluff


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## mik_git (Feb 4, 2004)

Hmm, most of my engineering stuff is a distant hazzy memory, and we didn't do much in the way of butting, but i think the point is more marketing than useful... like said before, if tripple is good, then quad must be way better. my dimaond back has "True Temper short butt" now this is either that the butt area is smaller, is closer to the end or is jsut the same but is "short butt" and therefore better than anything else.
But there is also the thing that they tried all sorts of stuff back in the early 90's, external butting, and remember those externally fluted down tubes. Ans also that different frames have fifferent stress area depending on the design, and the material, and the use. For a down tube maybe real think at the head and bracket, but a long butt from the top to reduce stress, then another butt to shave off a few grams, then need 2 more but to get back up to a decent size for the BB, but in fact none were the same size (4 sizes) hence you have a quad butt (i'm not proposing this is remotely true, just an example). look at waht easton did for the program tubing...


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## scant (Jan 5, 2004)

stranger still, how come you read it on fatcogs but asked on here? ;D


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