Most like Klien, Cannondale use a handheld belt sander to do this and will use different grade of belt to clean them up. However they use a form of welding where they will build up multiple layer of weld before they smooth them out. If you do this to your GT you severely weaken the welds and this is not recommended.
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Most like Klien, Cannondale use a handheld belt sander to do this and will use different grade of belt to clean them up. However they use a form of welding where they will build up multiple layer of weld before they smooth them out. If you do this to your GT you severely weaken the welds and this is not recommended.