Different weldtypes

[Belgium Cuda]

I know what a spotweld is but what other types of welds are there and how do they look? Have heard the name "buttweld" for example.

Per

[Cuda1971]

Does this help?

[dutch]

-spotweld:  2 x sheetmetal, no hole, electrode on both sides fusing the metal.                                                      "puntlas" in dutch

-butweld / plugweld:  2x sheetmetal, one hole, fil the hole welding inside it.                                                          "proplas"     

-stitchweld: for example, weld an inch then leave open an inch, weld another inch...                                              "kettinglas"

-mig/mag welding:  automatic wire feed to weldingtorch. uses protection gas.                                                       "mig/mag of co2 lassen"

-tig welding: uses weldingtorch with wolfram/tungsten core. Feed wire by hand. uses different protectiongas.     "tig lassen" 
   ( most used for welding stainless and alu )

-stickwelding: uses a weldingrod and no protectiongas                                                                                            "electrisch lassen"

[David_Lee]

-spotweld:  2 x sheetmetal, no hole, electrode on both sides fusing the metal.                                                      "puntlas" in dutch

-butweld / plugweld:  2x sheetmetal, one hole, fil the hole welding inside it.                                                          "proplas"     

-stitchweld: for example, weld an inch then leave open an inch, weld another inch...                                              "kettinglas"

-mig/mag welding:  automatic wire feed to weldingtorch. uses protection gas.                                                       "mig/mag of co2 lassen"

-tig welding: uses weldingtorch with wolfram/tungsten core. Feed wire by hand. uses different protectiongas.     "tig lassen" 
   ( most used for welding stainless and alu )

-stickwelding: uses a weldingrod and no protectiongas                                                                                            "electrisch lassen"

you forgot the oldest gas welding

[dutch]

the oldest would be a forge weld... 

[Belgium Cuda]

Thanks guys.

So I'm buttwelding my floors because I predrill and fill the holes? Can spotwelding be done at home?
I'm predrilling with a 8mm drill, is that to big?

When patching a panel, without overlap, is that then stitchwelding without openings?

Why spotweld or buttweld, why not weld the complete seam together? Are there other reasons then factorylook?

Sorry for all stupid questions.

Per

[72cudamaan]

no no no no no.... when you weld up a predrilled hole, that is a plug weld
                           when you weld two pieces of sheetmetal together (side by side), that is a butt weld. (the edges are butted up next to each other)
                            when you have a long strip to weld, you weld one inch,skip one inch weld one inch... until you're done this is stitch welding
                           A complete weld can make the joint weak, especially with sheetmetal, thats why the stitch weld.
                            And I don't think not understanding something makes for a stupid question.
                           Doing something without understanding it makes for a stupid outcome. 

[Belgium Cuda]

Great learning guys.

What about 8mm ( 5/16" ) predrill? Good size or?
Make more plugwelds then the factorydistance spotwelds or same?
Per

[Challenger III]

5/16" is a good size to pre drill. Make sure to start your weld from the center of the hole and "roll" your way out to the edge of the hole, to ensure you get a strong bond. I use a 1 1/2" spacing on most panels. Closer spacing for areas of higher stress ( fuel tank braces or floor pan to crossmember / subframe for example).   

[Aussie Challenger]

Drilling holes so as to "plug weld" can strengthen but the hole dia. needs to be larger as the thickness of the material increases, panel material doesn't need all that larger hole, 3/16" - 1/4" is more than adequate.