Spot Weld Drill Size?

[XFSTag]

Just a quick question to you chaps who have been replacing panels

What size drill have you found best for drilling out spot welds on the Stag?.

I am heading to Machine Mart Tomorrow and have this on my list for their VAT free day, along with a new welder and stuff. They do two sizes 3/8 and 5/16, both dedicated spot weld drills.

I am getting stuff ready for the work I have planned

Many Thanks

Glyn

[dasadrew]

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I've only ever seen the 3/8" ones and so that is the size I use.

In actual fact, even using this size, you still get a couple of welds that are hanging on by a thread. One of the reasons is that you cannot easily see the real extent of the welded surface between the panels and cannot position the drill exactly on centre.

Some welds are also not simple round spots, but wander off in all directions.

Bear in mind that the spike in the weld cutter is not enough to hold the cutter on centre - you need to drill the spot with a small very sharp drill first - say 1.5mm, perhaps even centre-punching the weld first.

As the hole that the cutter makes is quite large, always use it on the bit you are going to throw away, although this is not always possible due to access.

You can get some idea of the gaping hole size at the bottom left corner of this pic where I drilled off the inner valance panel and needed to reuse both it and the rear light panel.

Drew

[XFSTag]

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Thanks Drew

Much appreciated, I know you have done a few

Now off to save some VAT!

Cheers

Glyn

[charliebridger]

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i used that spot weld drill nightmare it shoots of and centre locating spike keeps breaking i found better results with this

http://www.frost.co.uk/item_Detail.asp?productID=9087&frostProductName=8mm%20Cobalt%20Spot%20Weld%20Drill

[XFSTag]

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Thanks Charlie

I haven't tried it yet but no doubt I'll need more than one

I have some underseal removal scheduled for this weekend ....can't wait