Plug welds

[Mr J Morton]

I've found some very suspect welding on my Triumph Spitfire, not done by me I hasten to add! I'm going to go over a few of the areas I know have been done by the same person(previous owner). The welds he has done are barely glued on.

The sills are the first job. I need to plug weld them but I would like to do it with out removing the existing welds, or separating the panels, how do I drill it out to 6-7mm for the plug welds without going right through? Is there a tool or technique for this?

thanks for the help in advance

Jonnym

 

[grim_d]

Spot weld drill with depth gauge maybe?

ETA : http://www.frost.co.uk/item_Detail.asp?productID=8501&frostProductName=Spot Weld Cutter

 

[drjim]

If you can get at both sides - ie it's the bottom edge of the sill/floor pan join - can you not just hire an actual spot welder and do it that way?

 

[fatfranky]

If you go about 3/4 of the way down page 5 of this thread you will see some tips on sharpening a spot weld drill

Hope it helps

http://retrorides.proboards.com/index.cgi?board=readersrides&action=display&thread=65793&page=5

Regards

Frank

 

[bigbadbugga]

Use a spot weld drill as already suggested, you will feel it go through the first layer if you take your time and don't press to hard.

 

[chip-kobb]

just a little bit of a cheat for you , if you drill all the way through two pieces of steel whilst they are clamped together then remove burr from rear face you can plug/puddle weld them by placing a suitable lump of copper or brass behind/under holes, use plenty of heat, copper and brass are non-ferrous (no iron content) and can be removed with a "tap" from a hammer afterwards. practice a few times on a bench with a bit of scrap before hand to get settings, Hope this helps