porous welds

[Muddi Camel]

Hi. Just been playing with my "new" snapon/cebora 130 (from ebay). The welds seem porous every now & then - & will all of a sudden go clean again.
I'm using an argon mix disposable, which I've had to turn up to max so I can hear any gas coming out.
The end of the swan neck seems to have been damaged at some stage, but there are still clear holes there.

any recomendations?

Thanks

 

[Welderpaul]

Could be one or more of the following:

1. Gust or draught blowing your shielding gas away. Make sure you are in a shielded area to prevent this happening.
2. Gas has run out. Disposables don't last very long. Make sure you can still hear the gas coming out.
3. Dirt, rust or oil contamination on the steel that you are welding will cause porosity

Can you hear the gas coming out of the end of the torch? Make sure you don't feed the wire into your ear trying to find out...

 

[Muddi Camel]

I'm doing it in the garage to ensure there's a shield
New bottle
I'll clean the steel in a mo' & try again

Gas coming out- ummm very,very quietly. I'm not convinced that the regulator, hose swan neck is wonderful. I'm sure I can pressure test it - somehow.

Thanks for the super speedy response. I'm going back outside now & see if I can weld the fridge to the bench or something

 

[Welderpaul]

Never used disposables myself but seems to be the cause of most gas-related problems on here!

 

[Muddi Camel]

Thanks. You're probably right. The gas on max & cleaning the joint helps - sort of.
Beating the poo out of some of my tests shows that some parts are still porous, otherwise the work'll fail @ the edge of the zone - as I'd hope.
Would a new reg & hose help? The gas starts just before the wire feeds, but I don't know if there's enough. The guage reads approx. 10.5cfh

Thanks

 

[Welderpaul]

cfh is cubic feed per hour - the rate at which the gas leaves the nozzle. You have the rate set correctly.
I dont think there is a contents guage on that type of regulator - that would tell you straight away if it was empty.
Don't know much more about disposable bottles - sorry!

 

[Wozzaaah]

10.5 cfh is just under 5 lpm. If the scale is definitely cfh then that seems a bit on the low side.

 

[Welderpaul]

10.5 cfh is just under 5 lpm. If the scale is definitely cfh then that seems a bit on the low side.

Oh sh1t yeah!

 

[engybenjy]

Shouldn't the flow be around 10/12lpm for mild??

 

[Welderpaul]

yeah - 10 LPM

 

[Wozzaaah]

That's about right Ben, the low flow probably explains why Muddi is getting a a bit of porosity. The trouble with those mini regs is getting them to supply enough gas, they quite often have to be fully open.