Head Type
This characteristic is linked to choosing the adequate self-drilling screw. In the DEGOMETAL product line, there are three groups of head types: Pan, Hexagonal or Countersunk head.

Threading options

The penetration speed of the screw into the drilled support surface depends on the pitch of the thread. The threading of DEGOMETAL selfdrilling screws depends on the dimensions established in compliance with DIN 7504 standards.

Drill bit

The longer it is, the thicker the support surface can be. It can also have two wings which are important for steel-wood screwing. Created through forming, it enables the drilling of the support surface before screwing. On the steel self-drilling screw, the cementation performed after forming enables it to drill steel, aluminium and stainless steel.

However, since this treatment is not possible on stainless steel, the A2 stainless steel self-drilling screw can only drill aluminium.

Print Type

SDepending on his choice, the operator can save 40% of the screwing time.

Knurled head (option) 
Only for steel self-drilling screws, it slows down the unscrewing even after prolonged vibration. Knurls on TFA & TFA ET screws are tronconic (consisting of 4 lobs): this makes chamfering wood possible during the screwing stage.

On the A2 stainless-steel self-drilling screw, knurls are not advisable, because they scratch the paint of the aluminium support surface during the screwing stage. Aesthetics is of paramount importance when it comes to aluminium joinery.

The drilling depth depends on the length of the drill bit. The TFA-EC and TFA ET screws have two wings that ease penetration into soft materials before breaking against the metal sheet. The diameter of the screw drill as well as the material to be drilled determine the rotation speed and thus the speed of the process.

We can provide screw driver bits.

Screwing without pre-drilling: the self-drilling screw drills and screws support surfaces all at once.

	Pan head Usually used on thin metal sheets.
	Hexagonal Wide, often used with a Neoprene washer. Can be used with high rotation torque.
	Countersunk Exact fitting of the head in the support surface for a perfect finish..

DEGOMETAL also offers a High-Performance Chipboard Screw: WOODFAST.

It is particularly recommended when screwing is diffi cult or under certain constraints like a highly crumbly wood (large-particle chipboard) or hard exotic woods.

With the WOODFAST Screw, screwing into cutting edges and rims becomes possible and easy.

WOODFAST can also be used in the industrial fi eld with automatic feeder bowl systems.

The WOODFAST screw is recommended for difficult assembly.

The torsional strength of self-drilling screws must be such that, during an ISO 10666:1999 (F) compliant test, the necessary breaking-point torque is equal or superior to minimum torque values in the following table:

Drilling capacity

The tip of the self-drilling screw has to be shaped so as to drill a steel plate, which is needed for the shaping of the internal thread, under conditions specifi ed in ISO 10666:1999 (F) standards.

Internal thread or threading capacity

The self-drilling screws must be able to tap the drilled bore, in accordance with previous point, without having their own threading distorted, when screwed into a test plate, in compliance with ISO 10666:1999 (F) standards.

DEGOMETAL also offers a High-Performance Chipboard Screw: WOODFAST.

It is particularly recommended when screwing is diffi cult or under certain constraints like a highly crumbly wood (large-particle chipboard) or hard exotic woods.

With the WOODFAST Screw, screwing into cutting edges and rims becomes possible and easy.

WOODFAST can also be used in the industrial fi eld with automatic feeder bowl systems.

The WOODFAST screw is recommended for difficult assembly.