Air bubbles in the welds
#1
Thread Starter
Senior Member
Joined: Jul 2006
Posts: 213
Likes: 0
Air bubbles in the welds
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?
#2
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.
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.
__________________
"Surely one can love his own country without becoming hopelessly lost in an all-consuming flame of narrow-minded nationalism" - Fred Birchmore
"Surely one can love his own country without becoming hopelessly lost in an all-consuming flame of narrow-minded nationalism" - Fred Birchmore
#3
Industry Maven

Joined: Oct 2003
Posts: 2,936
Likes: 0
From: Wherever good bikes are sold
Bikes: Thylacines...only Thylacines.
Originally Posted by PIZZ
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?





