Odd bit on a frame - maybe odd person asking about it

[lewisfoto]

Most likely they saved 2p per frame by brazing one side, multiplied by 100,000 frames and the savings pile up. Bean counters prevail!

 

[Midlife]

aende missed the bridge off on a lot of frames, that plus his usual routine of chopping and filing bits led to a number of chainstay failures

Not sure that would be a problem with the Raleigh though

shaun

 

[Old Ned]

My Dynatech MTB is like that as are lots of Raleighs of the same period (early 90's?). Just enough to take a mudguard clip. Why would you need any more :?

 

[oonaff]

wierd. it looks like they scrimpt on the other weld. loads of other frames bridge right across and thats neater. also you are reducing the size of the triangle in plan [well you know what i mean] this would make a stiffer structure, maybe thats it ? they wanted a slightly more compliant structure. the title of the topic says 'odd' and i agree.its out of the way granted , but to break common sense for the sake of a m guard ?
what was this m guard clip ? some kind of a slip/slide in thing.or is there another purpose, like m to clamp the frames on a production line ?

 

[Woz]

Surely a few more layers of dirt would help conceal the gap on the bridge - then it will appear how it should. :facepalm:

 

[Logic.Al]

My M-Trax is the same

 

[Old Ned]

I've had several frames over the years without a bridge here. Generally short wheel base ones where it doesn't seem to make any difference to the rigidity.

 

[danson67]

I think it probably is just a bit of bean counting on Raleigh's part.

As said above, the chainstay bridge is marginal use structurally (maybe we should just call it the 'mudguard mount'), but built this way at least it can be brazed in place on the LH stay as a loose tube, before the rear end is brazed into the BB.
That way the 'bridge' is far easier to mitre, heat, braze and clean up, and (unlike a standard double ended bridge) the contracting brass doesn't put the dropouts out of alignment, saving a lot of trouble in frame prep later.

Still look horrible,though.

All the best,

 

[TGR]

hey Dan,

Long time.

Thanks, it looks odd to me but mudguard mount it must be.

Thanks all for concentrating on the odd bit and not the odd person!

Richard

 

[mattr]

I've seen that sort of feature on a good number of frames, at the cheaper end they were mostly using heavier gauge or over size tubing. At the top end, it was usually the stiffer end of the market, tigged 853, titanium or oversize aluminium.

Think my current training bike has a half bridge. But that's OS and hydroformed aluminum, so really doesn't need any extra stiffness!