- Thread starter GeorgeB
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Why didn't you just put a hacksaw blade through the alan-bolt?
You mean the bolt which goes the length of the shaft as included in the photo? I'd already removed that. The shaft was stuck solid to the frame. In the image (above) you can see rust-like deposits still on the shaft.
You've reminded me of another aspect. At the top of my image (above) is the bolt which holds the handlebars in place. This was easy to unscrew. But, by design, I can't see any flexibility in the assembly/clamp so, to remove the handlebars, I decided to cut away the clamp. It's that cut which I seek to weld or glue back in place.
How did they get the drop handlbars into the clamp in the first place? And is there a way of removing the handlebars without cutting the clamp?
How did they get the drop handlbars into the clamp in the first place? And is there a way of removing the handlebars without cutting the clamp?
George, seriously DO NOT TRY AND WELD THAT STEM BACK TOGETHER!
Chances are (given the origonal wheel size mentioned back when this all began) the frame is a simple steel, rather than a posh alloy steel. Structural aluminium is NEVER a simple alloy. That stem was not welded when it was manufactured but forged in piece by the looks of things. It could be made from a non weldable aluminium alloy, it is probably a heat treated alloy (weld a heat treated alloy and the result is at best loss of around 40% of it's strength if the welder knows what they're doing, less if they don't!).
If the God of welding fixed it it would be softer and weaker than origonally and then there's the location of the weld to consider i.e. not only must the hole for the bars be precisely sized (too tight and you'll never assemble things, too loose and IT WILL BREAK when tightened enough to hold the bars) but the area is subjected to a huge amount of stress when pedalling out of the saddle
Go and buy a new stem. They're not expensive but do take your bars with you as clamp diameters vary- IIRC standard diameter @ the clamping region for bars is 25.4mm BUT there are all sorts of oddball sizes due to the Italians, Cinelli stems/bars being 26.something mm for example
Chances are (given the origonal wheel size mentioned back when this all began) the frame is a simple steel, rather than a posh alloy steel. Structural aluminium is NEVER a simple alloy. That stem was not welded when it was manufactured but forged in piece by the looks of things. It could be made from a non weldable aluminium alloy, it is probably a heat treated alloy (weld a heat treated alloy and the result is at best loss of around 40% of it's strength if the welder knows what they're doing, less if they don't!).
If the God of welding fixed it it would be softer and weaker than origonally and then there's the location of the weld to consider i.e. not only must the hole for the bars be precisely sized (too tight and you'll never assemble things, too loose and IT WILL BREAK when tightened enough to hold the bars) but the area is subjected to a huge amount of stress when pedalling out of the saddle
Go and buy a new stem. They're not expensive but do take your bars with you as clamp diameters vary- IIRC standard diameter @ the clamping region for bars is 25.4mm BUT there are all sorts of oddball sizes due to the Italians, Cinelli stems/bars being 26.something mm for example
Thank you for the latest warning. I accept your advice and will not be welding that part. I'll glue it instead because it's more of a known quantity. It may sound daft but I'm confident it will work, unless Alfaman's part is a good match.
Now you tell me that the frame is probably bog-standard steel, so all the warnings about the risk of welding 'special' steel might not have been relevant after all!
Trying to glue it is even more daft/dangerous!!!! Take up Alfaman on his kind offer (assuming his stem is the same diameter as yours) or buy a new one! Even if i'm right (and it's an educated guess based soley on the fact that the wheel sizes mentioned don't really go with lightweight high end bikes) the comments about the steel welds are still relevant, it's just a case that if it is a simple steel it'll be 'damaged' less than a posh alloy steel- the HAZ is a little less of an issue but plenty of other potential problems remain
Drains
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the snooper
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George i have to agree with the other posters on here gluing that stem for the handlebars is ridiculous for the price of a new one its simply not worth it
don't you put any value on your health I'm sure your family will, your good health is worth more then a few measly quid saved
don't you put any value on your health I'm sure your family will, your good health is worth more then a few measly quid saved
Glue is used in many 'serious' industrial applications. I won't hesitate to use it if a replacement is not as good as the original part. As for potential problems - if my bicycle frame really is mild steel, then what about some of the amateur welding jobs we see on cars at this forum and on other sites? At first look, you'd think the rust-riddled vehicles should go straight to the scrap yard but, no, someone with a MIG welder uses miles of MIG wire to replace acres of steel sheet. All those new joints may not fail an MOT but is the resultant vehicle really safe? If those vehicles were put through accident crash testing, how would the restored bodies stand up to simulated impact damage?
Good joke! George, you do make me laugh.
OK - because I relish the challenge/gamble of trying to prove people wrong, this is what I'm going to do, just for the hell of it!
the snooper
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george a gamble is good and also proving to people that things can be done is also a good thing but not at the possible expence of your health anything can be done with the right gear.
but bikes are not sold arc welded together nor are handlebars glued in and there is good reason for this because it not a safe way of doing it, if it were we would buy them like that from the shops
but bikes are not sold arc welded together nor are handlebars glued in and there is good reason for this because it not a safe way of doing it, if it were we would buy them like that from the shops
Yep planes, F1 cars and a bunch of other stuff are glued together. The glue used is a little different to a tube of araldite rapid though not to mention a damn site more expensive than a new bloody stem that'll cost less than a score! There's also the small matter of joint design- glued joints are very different set ups to welded joints because the preocess is completely different
In many cases putting one through a crash test would be eye opening however if a badly welded sill/wheelarch/floorpan patch fails the car doesn't stop working as a car i.e. it's not guarenteed to result in a painful and potentially fatal accident (as you're run over by the bus that wasn't expecting the cyclist to headbutt the road as his bike disassembles itself for example).
The well meaning amateur also has their work inspected yearly at MOT time and in the case of heavily modified/homebuilt cars has a bunch of red tape to wade through and engineering inspections (BIVA or whatever replaced the SVA) to pay for- in part because of those that refused to listen to advice and realise when they are taking on work beyond their current skill set with regards to design/fabrication/welding/tools etc and simply waded in because they wanted to and lidl sell welders for £30
Drains
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George, lots of people on this site, including me, and in plenty of other places, do repairs and fixes to bits of kit that the majority of folk wouldn't dream of doing. We take something that others would chuck in the bin, we use our skill and knowledge, the tools we have to hand, and useful leftovers and scrounged bits, and we fix things. It's great. I love it! I live to mend broken stuff. I'm proud of my ability to do these things. So, i'm sure, are you!
But sometimes I think that either my skills/ tools/ useful bits, just won't do the job. Sometimes the big red warning flags go up, and I realise that I don't know what I'm doing, or that what i'm doing is just wrong, or dangerous, or stupid.
What I don't do is try and prove people wrong for the sake of it. I do things because I can, not because other people say I can't, whereas you seem to have an unquenchable need to take up a challenge nobody has set. You ask advice, or at least tell us what your up to, people tell you you might be headed in the wrong direction, and that's it, the red mist sets in, and you want to wage war on the naysayers. At least this time you had the sense to listen when you were told not to try welding aluminium. Instead, you throw a total curveball and decide to use glue. I was genuinely aghast, until I found it funny. But it's not funny, because it's serious, and you might hurt yourself, and believe it or not, although I don't know you, I do actually care that you don't go ahead and do something stupid, just because people have told you it's stupid.
Just take care George. Take care.
cookie munsta
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C'mon jokes over. lets get back to welding
We've had the **** taken out of us, and seen the word "may" pushed to its limit. as in it "may" fail.
I just hope the car that swerves to miss you doesn't hit any one else
We've had the **** taken out of us, and seen the word "may" pushed to its limit. as in it "may" fail.
I just hope the car that swerves to miss you doesn't hit any one else
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George
Well it is about welding bicycles , just not your bicycle !
Have you got a stem yet , I can look amongst mine , but I mainly have MTB rubbish [ all I am given ! ].
regards Paul
