High-low thread-forming screws
High-low thread-forming screws for plastic and other low density materials, with alternating high and low threads. Share the thread size, dimensions, and mating material, and we'll review them before quoting.
What it is and how it works
Screws with a thread profile that alternates high and low threads.
How it works
The spacing between threads leaves mating material between the crests. The specific application depends on the plastic, the hole, and the requested geometry.
What sets it apart
The high-low pattern distinguishes it from Plastobular's lobular body and from a uniform machine screw thread.
When it's typically considered
Considered when the requirement specifies a high-low thread or one is being evaluated. We review the mating material and application with you.
Substrate and application
Plastic and other mating materials only when the specification or technical review supports it.
KEY POINTS TO SPECIFY
Use these references to describe your part and fill in only what you already know.
Documented designations include 3-28, 4-24, 5-20, 6-19, 7-19, 8-18, 10-16, 12-16, 1/4-15, and 5/16-14. If your drawing calls for a different size, note it in your request.
What to send
Share the part number, drawing, or sample part, plus the dimensions, estimated quantity, and any known requirements. If something is still to be defined, note it in your request.
What helps us quote
Mating material, designation, dimensions listed separately, part number, drawing, or sample part, and volume.
What each team can bring
Purchasing
Share the part number, quantity, order frequency, and required material and finish.
Engineering
Specify the mating material, the hole if known, the thread designation, dimensions, head, and drive.
Quality
Provide pull-out or installation criteria when part of the customer's specification.
Key points to specify
Thread, profile, and point
Thread size
View head and drive references
These references help describe your part. The full list is available in the quote request.
Head styles
Flat head 100°
Flat head 82°
Flat undercut head
Flat top head
Binding head
Binding undercut head
Button head
Cheese head
Fillister head
Fillister head (cap screw)
Indented hex washer head
Indented hex head
Indented hex flange washer head
Oval head
Oval undercut head
Pan head
Pan washer head
Round head
Round washer head
Truss head
Truss washer head
Low-profile truss head
Wafer headDrive types
Torx-style 6-lobe drive
Security Torx-style 6-lobe (tamper-resistant)
Slotted
Square drive
Combination drive (square + Phillips)
Combination drive (square + Phillips + slotted)
Combination drive (Phillips + slotted)
Combination drive (square + slotted)
Phillips
Pozidriv (Type IA)
Allen-style hex socket drive
Security Allen-style hex socket (tamper-resistant)Under-head features
Full serrations
Nibs under head
ShoulderMaterial and finish
Enter the material, grade, and finish, or attach the specification. If you don't know them yet, you can leave them open.
Materials
Finishes
Fill in what you already know.
You don't need to fill in everything now. Your selections carry over when you continue.
If yours isn't listed, choose "Other specification."
Most common lengths. If yours isn't listed, choose "Other specification."
Measured under the head, except for flat countersunk heads (overall length) and oval heads (from the edge of the countersink). If your drawing uses a different reference, note it under additional requirements.
Head
High-low screws often have a smaller head than a standard screw of the same size (for example, a #8 screw with a #6 head). Tell us the head diameter you need.
Drive
You can continue with this family and fill in the rest later.
Continue your requestSend us your requirements. We'll review them and follow up.
You can start with a drawing, a specification, a sample part, a part number, or a description.