groho

While doing panel work, I took the opportunity to use two different spot weld cutters, a Keysco solid one piece, ALC77778, on my trunk, and a Blair double-ended cutter, BLR13214 on the quarter panel. The Keysco is a much better cutter, and lasts much longer, hands down. I was able to do my entire trunk using one bit. The con. . it's much more difficult to distinguish the top panel from the bottom panel, has a tendency to go too deep. this results in more prep work for the new panel and having to template the new panel, overlaying the spot welds. The Blair cuts a much more managable hole in about the same time, and other than some grinding to clean up the center material, the base panel is nearly untouched. Very nice! The con. . .I was breaking teeth every 5-7 spot welds. In the end, you're gonna spend more money on Blair replacement bits, but you get a better prep for the new panel. You can punch holes as needed versus the Keysco. The Keysco has the Blair knocked out with regards to durability. Enjoy your week ends.

JMD

There is always a trade off no?

racin66coupe

apparently just a good drill bit works best. haha

rmodel65

uni bits work good

Adrenolin

I tried a few weld cutting bits and was unimpressed to say the least, especially for the price of them. Bought a few regular drill bits (wood & soft metal type) for 4.99 each they worked great. I'd never waste my time with those spot weld cutters again. To each their own...

2+2GT

I've used both, and I'll go with the Keysco type. With a little practice, and I mean just a little, depth control is no problem.

jcoby

i've used hole saw style, solid style, drill bits, chisels, grinders, saws and screwdrivers. the solid style is by far the best. the hole saw style tend to wallow and make an odd-shaped hole and break teeth easily. drill bits cut too deep into the second layer and tend to wander. the solid style take a little practice but they're very controllable and if you stick a wedge in there, you'll know pretty quickly when you're all the way through.

JMD

I tried one of those spotweld cutters once, in short order I switched to regular drill bits also...

fakesnakes

1/4" drill bit and a panel knife. Drill all the way through, separate them with the knife, and use the hole in the panel that is staying as the spot weld hole for the new panel. This works in almost every situation except where the panel that is staying can not be accessed from the other side, but this is rare.

vineman

regular drill bit ftw! Just have some control over it.