Type 17 Hex Screw With XGRiP

Type 17 hex head screws with XGRiP

These are Hobson DRiLLX Type 17 self-drilling screws, 12 gauge with 11 threads per inch, a hex head, sealing washer and XGRiP. Hobson designs the Type 17 point for drilling through lighter steel sections and fastening into timber, and its data sheet lists these for crest fixing, sheds, metal to timber applications, and roofing profiles and wall cladding to timber and steel battens up to 1.5mm. They are C1022 hardened steel with a Class 4 finish.

Under the head, a short XGRiP thread clamps the sheet onto the seal, which keeps it watertight when the roof is walked on. Hobson's product data lists them with Scratchguard (AS3566 + scratchguard); Hobson's DRiLLX technical guide describes Scratchguard as protecting the shank from severe scratching or scouring when fixing metal roofing, which improves corrosion resistance.

What they fix into

• •Timber: Hobson's pull-out values (below) are for 35mm embedment in F7 pine and F27 hardwood. As a general rule, Hobson asks for at least 25mm of a 12 gauge screw in the timber for maximum pull-out.
• •Add the height of the sheet profile at the fixing point, and any packing the screw passes through, to the embedment you need. If that comes to more than the screw length, use the longer #14-10 Type 17 XGRiP screw; for 14 gauge, Hobson's general rule is at least 35mm in the timber for maximum pull-out.
• •Steel battens: up to 1.5mm (Hobson's data sheet). Hobson's drill point test for this screw is in G550 steel 0.55mm thick. It publishes no pull-out values in steel for this screw.
• •Thicker steel? Use a metal point tek screw with XGRiP, for which Hobson publishes pull-out values in steel up to 3.8mm.
• •How many screws go in each sheet and batten comes from the roof sheeting maker's installation guide or the building designer, especially in high wind areas.

Type 17 #12-11 sizes and packs

Both lengths have a 14.5mm head, 5.5mm high, with a 5/16 inch hex drive. 11 TPI is a coarse thread by Hobson's definition (up to 16 TPI). Select a row to open it in the selector, then pick the colour.

Pull-out values in pine and hardwood

Hobson publishes laboratory pull-out values for this screw in the timber shown, at 35mm embedment, and they hold only for that timber and embedment. Hobson notes safety factors should be considered for design and actual pull-out loads may differ slightly depending on the base material. It gives no edge distance, spacing, sheet pull-over or wind uplift figures.

Screw strength (Hobson): torsional 9.4Nm; tensile 13,950N mean and 11,050N characteristic; shear 8,350N mean and 6,650N characteristic.

Drill point test (Hobson): through G550 steel 0.55mm thick at 2,200 RPM with an 18kg load, 3.5 seconds maximum for any one screw and 2.5 seconds maximum on average.

Painted heads to match COLORBOND roofing

Unpainted, or with heads painted in 33 colours from Hobson's COLORBOND list, each named in the selector. Gully, Monument, Surfmist (Titania) and Wallaby come in 65mm only. Hobson's warranty covers the screw, not the paint. COLORBOND is a registered trademark of BlueScope Steel Limited.

Class 4 coating and warranty

Class 4 (AS 3566.2) is a 38 micron mechanically galvanised finish, which Hobson's finish guide places at severe marine (C4) exposure. Warranty periods from Hobson's 2025 self-drilling screw warranty:

• •Hobson's 2025 warranty covers the exposed head and washer only, not the shank or the look of the coating. It needs screw gun installation and fresh water wash-downs (six-monthly in C2 and C3, three-monthly in C4 and C5), pays replacement product plus freight only, is personal to the original purchaser and needs claims in writing. Micro-environments (sheltered, unwashed or polluted spots) must be disclosed, and on a category boundary the higher category applies. Read the full warranty before relying on it.
• •In very severe marine (C5) sites Class 4 is not recommended and only 316 bi-metal is covered (see roofing screws). Extreme (CX) sites need Hobson's written confirmation first; ask us if you are unsure of your site's category.
• •Treated pine battens: the warranty excludes contact with incompatible materials, and Hobson makes its Tykote coating specifically for treated pine, so ask us before using these in treated pine.

How to fit Type 17 XGRiP screws

Steps 1 to 3 are the installation guide on Hobson's data sheet (260709DS). The points after them are general roofing practice, not Hobson instructions.

1. Use a cordless screw gun set between 2,200 and 3,000 RPM with a 5/16 inch hex drive. Hobson's sheet recommends its impaX magnetic (45 or 65mm), standard magnetic (45 to 150mm) and impaX spring (65 and 150mm) nut setters. Fit the drive over the screw and place it at the fastening position. Hobson does not recommend impact drivers.
2. Apply consistently firm pressure to the screw gun while the screw is drilling.
3. Take care not to overtighten the screw (Hobson's words).
4. General practice: hold the screw square to the sheet, and stop driving once the seal is seated on the sheet.
5. General practice: clean off the drilling swarf, which rusts and stains the sheet if it is left there.

Type 17 XGRiP screws in Adelaide

Allmat supplies Type 17 XGRiP screws, roofing screws and nut setters, with the timber battens and framing to go with them, to roofers, shed builders and trade across Adelaide and South Australia. Add them to a quote with the rest of your list and we will price the lot.

Questions