Site:MMA Weld techniques/pictures.

[Ratcatcher]

Well first real post after having a generalised look through the site and i've got to say i'm quite impressed with it's lay out and open information.
I have been a stick welder for many many moons and taught kids over the years but i've got to say that whoever designed this site actually has their head screwed on.

One thing i might add though on the mma/stick run through/pictures etc:
This hasn't happened to me on every test but i've done a lot with backing straps.
Any chance you could include pictures of welds with a backing strap even if it's just a m/s back for the newbie kids.

Pictures to the newbies are better than a thousand words..........

Just a thought.

Rat.

 

[malcolm]

That sounds like a good idea. We need to do another session on the MMA tutorial to cover vertical up so we could take some photos of backing strips at the same time.

What would be the advantages/disadvantages of backing strips? I guess they make the root easier (big benefit for me - still haven't got them right) and can provide a place to start and stop the weld. Noticed some weld procedures say not to use them - what are the disadvantages?

Also I guess the choices are brass and mild steel. Would you just grind them off when finished?

 

[TechnicAl]

That sounds like a good idea. We need to do another session on the MMA tutorial to cover vertical up so we could take some photos of backing strips at the same time.

What would be the advantages/disadvantages of backing strips? I guess they make the root easier (big benefit for me - still haven't got them right) and can provide a place to start and stop the weld. Noticed some weld procedures say not to use them - what are the disadvantages?

Also I guess the choices are brass and mild steel. Would you just grind them off when finished?

a few disadvantages I can think of

MILD STEEL
Removing isnt easy
You need a similar grade otherwise the dilution could be a problem
Non removable can cause notches which will intensify stresses

COPPER
copper in the mild steel can cause cracking
need remachining regularly