Quality welds- you be the judge

[Owen]

Like a row of scallops!! This is how it should have looked. Origin Boats Photo

In the case of MIG welding, the fish scale pattern that everyone seems to think means its a good weld is largely cosmetic and in cases like above would undoubtedly fail mechanical testing due to lack of uniform penetration. There also a lot of stress raisers there in an area that is likely to flex. [Edit: After looking at the photo's on my PC instead of my phone, the area may not flex given the thickness and stiffeners, but the weld is still not one to hold up as perfect by any means]
If done correctly it allows builders to ensure uniform appearance of the welds across the whole boat. Especially in cases where more than one person are welding.
The machine in use there has a function called synchropulse (sometimes call double pulse)
It "pulses" the amount of wire coming out to give a fish scale effect. If its in use there then the frequency is set too low for the travel speed. A higher frequency would bring it closer together giving uniform penetration.

The manifolds shown were done with a TIG. Not practical to do large jobs and heavy materials that way. Your tinnie would cost about five times as much.

As far as I know there is no requirement for boat builders to do any sort of pre qualified weld procedures or post weld testing.

Of course it's a "be careful what you wish for Dorothy" thing.
If such measure were introduced it would raise the manufacturing costs dramatically and virtually eliminate the kit boats.

[Bull]

Have a look at AS/NZS 1665
All welds need a Weld Procedure Specification
All welders need to be qualified or certified
There are plenty of back yard boys building boats without WPS and using guys who aren't qualified to those procedures.

[Owen]

Have a look at AS/NZS 1665
All welds need a Weld Procedure Specification
All welders need to be qualified or certified
There are plenty of back yard boys building boats without WPS and using guys who aren't qualified to those procedures.

Whilst I'd love to read it, I'm not going to buy it to do so. The sample download doesn't allow me to see the section on weld profiles etc.
Given that it's a welded structures standard not specific to boats, I presume that some other bot specific standard such as AS 1799.1-2009 specifies that all welding must conform to the former?
This info seems to support your post with regard to vessels that must be surveyed, but it's unclear if other vessels must have the same standards applied.
http://www.msq.qld.gov.au/~/media/ms...ding_quals.pdf

[Shark Poker]

In the case of MIG welding, the fish scale pattern that everyone seems to think means its a good weld is largely cosmetic and in cases like above would undoubtedly fail mechanical testing due to lack of uniform penetration. There also a lot of stress raisers there in an area that is likely to flex. [Edit: After looking at the photo's on my PC instead of my phone, the area may not flex given the thickness and stiffeners, but the weld is still not one to hold up as perfect by any means]
If done correctly it allows builders to ensure uniform appearance of the welds across the whole boat. Especially in cases where more than one person are welding.
The machine in use there has a function called synchropulse (sometimes call double pulse)
It "pulses" the amount of wire coming out to give a fish scale effect. If its in use there then the frequency is set too low for the travel speed. A higher frequency would bring it closer together giving uniform penetration.

The manifolds shown were done with a TIG. Not practical to do large jobs and heavy materials that way. Your tinnie would cost about five times as much.

As far as I know there is no requirement for boat builders to do any sort of pre qualified weld procedures or post weld testing.

Of course it's a "be careful what you wish for Dorothy" thing.
If such measure were introduced it would raise the manufacturing costs dramatically and virtually eliminate the kit boats.

After reading his post a few times I have to agree.
Owen has described this better than I have.
However, could we now apply our thoughts towards the goal of how to repair or improve the rocket launcher?

[madmackrel]

It's all beginning to sound like a peeing contest

[cobiaman]

This is a perfect opportunity for a weldoff!!!!

[Shark Poker]

This is a perfect opportunity for a weldoff!!!!

I think the peeing contest has some potential as Fathers' Day is approaching fast. Could be a father & son's type of event.
We could all meet near a boat ramp somewhere!