Framebuilders - Air bubbles in the welds

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I just got a hand built frame from a friend that builds frames but I noticed that on a few of the welds there are 1 or 2 small holes in the weld. Like air bubbles. Does this affect the weld in any way?
Cyclaholic
09-27-06, 08:49 AM
I'm no framebuilder but I know a little about welding so here's a few possibilities.
What is the frame made of? If its an aluminum frame then you're probably looking at hydrogen contamination. Molten alu has a great affinity for hydrogen, but as the molten alu cools into a solid it expels the dissolved hydrogen gas causing little bubbles.
In MIG welded steel it could be a sign of poor shielding gas coverage where atmospheric gasses contaminated the weld pool.
Its difficult to say if the strength of your welds are compromised without actually inspecting it.
Thylacine
09-29-06, 12:09 AM
I just got a hand built frame from a friend that builds frames but I noticed that on a few of the welds there are 1 or 2 small holes in the weld. Like air bubbles. Does this affect the weld in any way?
Why don't you ask your friend?
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