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Most would probably reach for the TIG for a small item like that but other processes would work too however...
Motorbike fork clamps, unknown alloy, unknown temper, critical part... i'd buy a new one if available. Where's it cracked (overtightened bolt on one of the split clamps?) out of interest?
Motorbike fork clamps, unknown alloy, unknown temper, critical part... i'd buy a new one if available. Where's it cracked (overtightened bolt on one of the split clamps?) out of interest?
chunkolini
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That sounds like a well dodgy thing to be repairing, I think I'd be lokinf for one from a breakers. A quick way to die if it fails in use.
Chunko'.
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darthmojoe
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i wouldn't recommend welding a yolk as some contain magnesium for strengthening (very flamable thats why its banned in alloy wheels for cars as far as i can remember)and any tig welding is not gonna penetrate all the way through.
There's a very big difference between an AlMg alloy (that contains a few percent mag) and a Mg alloy that's around 90% mag with a little aluminium, zinc and other ingredients but my money's on an silicon based alloy- either AlSiMg or AlSiCu
Magnesium isn't banned for automotive use, far from it in fact. As well as wheels (for those with deep pockets) it's being used more and more in the search for better fuel economy- excellent strength to weight ratio and castability. VAG have used it for ever for various castings, these days more and more manfacturers are using it for components like steering wheel cores, seat frames, various drivetrain castings, the inner frames of some panels as well as varoius brackets- there's a good 10-15kg of mag in many modern cars
While mag swarf, ribbon etc are very flammable (as is custard powder) a chunk of the stuff is actually very hard to ignite. Welding mag isn't really any more dangerous than welding anything else (just make sure all swarf is cleaned up!)- there's a mag foundry near me (primarily aerospace components) that have a full time welder on site whose main job is repairing castings that failed QC. No problems regarding penetration if the repair is prepped properly
Magnesium isn't banned for automotive use, far from it in fact. As well as wheels (for those with deep pockets) it's being used more and more in the search for better fuel economy- excellent strength to weight ratio and castability. VAG have used it for ever for various castings, these days more and more manfacturers are using it for components like steering wheel cores, seat frames, various drivetrain castings, the inner frames of some panels as well as varoius brackets- there's a good 10-15kg of mag in many modern cars
While mag swarf, ribbon etc are very flammable (as is custard powder) a chunk of the stuff is actually very hard to ignite. Welding mag isn't really any more dangerous than welding anything else (just make sure all swarf is cleaned up!)- there's a mag foundry near me (primarily aerospace components) that have a full time welder on site whose main job is repairing castings that failed QC. No problems regarding penetration if the repair is prepped properly
That's an odd area to crack. It wouldn't be instant death if it failed - the bottom yoke still holds the forks, and the steering stem is under the yoke. What that's doing is attaching the handlebars to bike. If it cracked all the way through at the bottom point, you've still got the forks clamped through the holes, so the bars will stay on - no death, still rideable but not advisable.
Did someone overtighten the nut that goes through that part?
what bike is it from? I'm reckoing it's from something old and Japanese, given the fork size. Prolly hard to get these days?
Did someone overtighten the nut that goes through that part?
what bike is it from? I'm reckoing it's from something old and Japanese, given the fork size. Prolly hard to get these days?
Castings aren't known for their ductility. If that were to fail catastrophically (very unlikely for it to become detached from the steering stem due to the pinch bolt) the extra stress on the lower yoke could break that too.
If there's zero chance of a replacement then it'd be a case of stripping the paint off, removing the crack (after crack testing the entire thing, although that looks like it was overtightened at some point from the location of the crack) and welding with a suitable mandrel in place of the steering column to ensure a good fit afterwoods
If there's zero chance of a replacement then it'd be a case of stripping the paint off, removing the crack (after crack testing the entire thing, although that looks like it was overtightened at some point from the location of the crack) and welding with a suitable mandrel in place of the steering column to ensure a good fit afterwoods
