Sutton 8mm D204 Swan Neck Spot Weld Drill Bit - 8% Cobalt HSS

The Sutton D204 (item D2040080) is a swan neck spot weld drill in 8% cobalt HSS (HSS-Co8) with a bright finish. It has a flatted shank with a 60° taper for good location in the disconnector, and it cuts out spot welds when repairing vehicle body panels. It is a single size: 8 mm diameter, 38 mm overall length.

Spot weld drills are made for vehicle body repairs: quick and precise drilling through existing auto panel spot welds, so damaged panels can be released and replacements fitted. The spur point is designed to cut through the weld on one panel while leaving only a slight mark in the second panel. The centre nib gives accurate positioning and less drilling pressure without work hardening, and the shallow point design cuts through the top panel while only slightly marking the second panel. The 38 mm drill is a short, rigid design for spot weld pneumatic disconnectors, and the flatted shank with a 60° taper gives good location in the disconnector.

Where this product is used

• Vehicle body repair: drilling out spot welds to release damaged panels before replacements are fitted.
• Drilling through the top panel while leaving only a slight mark in the second panel.
• Spot weld pneumatic disconnectors; the drill is also suitable for hand drills.
• Recommended speed: 500 to 800 rpm.

Finish

The bright finish is uncoated. Cobalt high speed steel improves abrasion and heat resistance for increased strength at higher cutting temperatures.

Speed

The recommended cutting speed is 500 to 800 rpm. The surface speed this gives at each size in the range is below (surface speed in m/min = π × Ø × rpm ÷ 1000).

Sizes and item numbers

Every size in the range, with its Sutton item number, flute length (l2), overall length (l1) and shank diameter (d2). Each item is a single drill.

Drilling notes

• Run at 500 to 800 rpm.
• The shallow point is designed to cut through the top panel and only slightly mark the second: stop as soon as the weld is cut through.
• Use the centre nib to locate on the weld, which reduces the pressure needed.
• Locate the flatted shank fully in the disconnector, so the 60° taper seats correctly.

Troubleshooting

• Drill breaks. Dull point: sharpen; Drill has front taper due to wearing: sharpen; Insufficient lip clearance on point: grind correctly; Lip clearance too great: regrind to correct clearance angle.
• Outer corner breaks down. Flutes clogged with chips: remove drill from hole and clear the flutes; Cutting speed too high: reduce speed; Dry cutting, no lubricant at cutting edges: apply cutting fluid.
• Cutting edges chip. Lip clearance too great: regrind to correct clearance angle; Feed too heavy: reduce feed.
• Hole rough. Dull point: sharpen; Feed too heavy: reduce feed; Dry cutting, no lubricant at cutting edges: apply cutting fluid; Fixture/clamping not rigid: secure job firmly.
• Hole oversize. Unequal angle or uneven length of cutting edges: regrind to same lip lengths and angles; Spindle run-out / loose spindle: check machine.

Key specifications

Related drilling products

Compare other Sutton drills: D203 hand spot weld drill and D205 revolver spot weld drill. Browse all Spot Weld Drill Bits. Need help choosing? Our guide to choosing the right drill bit and drill bit selection guide cover drill types and materials, and the speeds and feeds chart and cutting tool troubleshooting guide cover speeds and common problems.