Get Started

Grub Screw Size Chart Pdf Selection Guide | Hebei Wotu Fastener Manufacturing Co., Ltd.

Grub Screw Size Chart PDF

A grub screw size chart is most useful when it turns a vague request such as “small set screw” into a purchasable specification: thread size, length, drive type, point style, material, finish, and standard.

For buyers comparing or ordering grub screws, the chart should support the real application: locking a shaft, adjusting a component, preventing movement in a collar, or securing a part where a protruding screw head is not acceptable.

Request Quote View Products

Related Products

7-letter, 9-letter L-shaped anchor bolt (Chinese national standard GB/T799-1988 embedded anchor screw)

7-letter, 9-letter L-shaped anchor bolt (Chinese national standard GB/T799-1988 embedded anchor screw)

Brand: Wotu Surface: Natural black oxide treatment, customized hot-dip galvanized, zinc plated as required Specifications: Follow Chinese national standard GB/T799-1988, in stock M12-M48, total length 120mm~1500mm, nonstandard customized diameter, bending length, total screw length available Matching: Nuts, flat washers and spring washers of the same specification can be supplied in complete sets. Packaging: Bundling and packaging, using wooden pallets and film-wrapped export packaging in large quantities

Read More
Hexagonal Wood Screws

Hexagonal Wood Screws

Brand: Wotu Surface: blue and white zinc plated Specifications: Chinese national standard 6#/8#/10#/12#/16#/20#, rod length 35mm~250mm full range of specifications in stock, supports nonstandard length customization Packaging: 25kg cartons, full pallets packed on wooden pallets, support neutral packaging, private-label customization

Read More
Hex Head Self-Drilling Screw

Hex Head Self-Drilling Screw

Brand: Hengzuan Surface: color zinc plated Specifications: ST4.2/ST4.6/ST4.8/ST5.5/ST6.3, length 80mm～165mm in stock Packaging: 25kg cartons, packed in whole pallets, supports neutral private-label

Read More
Countersunk Head Cross Thick Thread Fiberboard Screw

Countersunk Head Cross Thick Thread Fiberboard Screw

Brand: Wotu Surface: color zinc plated electroplating Specifications: in stock 3.5/4.0/4.5/5.0 regular wire diameter, rod length 16～80mm full range of specifications in stock, supports nonstandard length customization Packaging: 25kg cartons, whole wooden pallets

Read More

Reading a Grub Screw Size Chart for the Right Fit

Size and specification notes

When reviewing grub screw options, compare the size chart against the functional details that change fit and performance: thread form, nominal diameter, pitch, length, socket or drive style, point geometry, material, coating, and any standard the buyer must match.

Criterion What To Check Why It Matters Buyer Tip
Thread standard and nominal size Confirm whether the chart uses metric, UNC, UNF, or another thread standard, and match the nominal diameter and pitch to the mating tapped hole. A grub screw with the right outside diameter but the wrong pitch can damage the internal thread or fail to clamp properly. Ask: Can you quote the grub screw by thread standard, diameter, pitch, and length exactly as shown on our drawing?
Length reference in the size chart Check how the PDF defines length for the grub screw type, especially for flat point, cone point, cup point, or dog point ends. Different point styles can change how much of the screw engages the shaft or component, even when the listed length is the same. Ask: Is the stated length measured overall, or from a specific reference face for this point style?
Drive type and hex socket fit Compare the socket size in the chart with the tool size used in assembly and maintenance. A mismatched socket increases the risk of rounding the recess, especially where the screw is adjusted often or installed in a confined position. Ask: What hex key size matches each grub screw size, and can it be confirmed on the drawing or datasheet?
Point style for the contact surface Select the end form according to the part being clamped: cup point for strong bite, flat point for reduced marking, cone point for location, or dog point for alignment. The point style affects holding force, repeatability, surface damage, and whether the screw can locate into a drilled seat. Ask: Which point style is recommended for our shaft or component material, and will it leave acceptable marks after tightening?
Material, hardness, and surface finish notes Look beyond the dimensions in the chart and confirm material grade, hardness range if required, and coating or black oxide finish. Two grub screws with the same size can behave differently in load holding, corrosion exposure, and repeated adjustment. Ask: Can the quotation state the material, finish, and any hardness requirement separately from the size chart?

Key Choices Before Ordering Grub Screws

The main distinction is that thread diameter and length do not describe the whole grub screw. Two screws with the same nominal size can behave differently if one has a cup point and the other has a cone, flat, dog, or nylon-tip point. The point controls how the screw contacts the mating part, how much marking it leaves, and how well it resists loosening.

A useful PDF size chart should also make clear which standard it follows, such as metric or inch sizing, because thread pitch, drive dimensions, and length conventions may differ. Before sending an inquiry, confirm whether the screw must match an existing drawing, a machine standard, or a replacement sample.

Start with the assembly, not only the diameter. A grub screw used on a rotating shaft may need a different point style than one used for a light adjustment stop. Cup points bite into the mating surface, flat points reduce surface damage, cone points can locate into a prepared recess, and dog points suit positive location where the receiving feature is designed for it.

Check the thread system and length convention. Metric grub screws are usually specified by diameter, pitch, and length, while inch sizes use their own thread designations. Length is normally measured differently from headed screws because the screw has no head, so the drawing or chart should remove any ambiguity.

Do not treat drive type as a minor detail. Hex socket, slotted, or other internal drives affect installation tooling, access, torque control, and serviceability. A hard-to-reach assembly may need a drive that operators can engage reliably without damaging the socket.

Send enough information for a clear reply. If you are asking Hebei Wotu Fastener Manufacturing Co., Ltd. about grub screws, share the required standard or drawing, size range, point style, material or surface treatment, and the application environment. If you are replacing an existing part, a photo and measured sample can reduce back-and-forth.

Criteria Importance Description Example Options
Thread system and standard Critical for interchangeability Metric and inch grub screws use different thread designations and may follow different dimensional standards. The chart should identify the system clearly so the screw matches the tapped hole and any existing drawing. A buyer replacing a screw in an imported machine should confirm whether the tapped hole is metric or inch before choosing from a chart.
Point style High impact on holding method and surface marking The point determines how the screw contacts the mating part. Cup points grip strongly but can mark surfaces; flat or soft-tip designs reduce damage; cone and dog points work best when the assembly is prepared for them. A shaft collar may use a cup point for grip, while a visible adjustment mechanism may need a flatter contact to reduce marking.
Length selection Important for engagement and clearance The screw must engage enough thread to hold while avoiding interference with internal parts or opposite surfaces. Because grub screws have no head, the length convention should be checked against the drawing or standard. A screw that is too short may loosen under load; one that is too long may protrude into a moving component.
Drive type Important for assembly access and serviceability Hex socket, slotted, and other internal drives require different tools and offer different levels of engagement. A poor drive choice can make installation difficult or increase the chance of damage during removal. A recessed location may need a drive that operators can reach cleanly with standard tooling.
Material and finish Application-dependent Material and surface treatment affect corrosion resistance, wear, appearance, and compatibility with the mating parts. These choices should match the operating environment rather than be selected from size alone. An indoor adjustment screw may not need the same finish as a part exposed to moisture or frequent handling.

Product Selection

Related Options

For a shaft collar, pulley, gear hub, handle, fixture, or adjustment mechanism, the right grub screw is the one that holds securely without causing unwanted damage or assembly problems. The size chart should narrow the choice, but the final specification should reflect how the screw contacts the mating part and how it will be installed.

Blog Articles / Reviews

How to Specify Countersunk Head Cross Thick Thread Fiberboard Screws for Furniture Assembly Projects

How to Specify Countersunk Head Cross Thick Thread Fiberboard Screws for Furniture Assembly Projects

Fiberboard screws are selected based on more than screw size alone. For furniture assembly and board-based applications, buyers need to match the screw structure with the characteristics of fiberboard, MDF, and similar engineered wood materials. A suitable specification should consider thread design, head style, screw length, diameter, installation method, and application requirements. For buyers sourcing […]

What Should an RFQ Include When Sourcing Dacromet Hex Head Self-Drilling Screw?

What Should an RFQ Include When Sourcing Dacromet Hex Head Self-Drilling Screw?

When sourcing dacromet hex head self drilling screw, a complete RFQ should define the application, screw configuration, coating requirement, dimensions, and supplier confirmation requirements. Buyers often receive different quotations because suppliers may interpret coating, size, drilling capability, or packaging scope differently. Before preparing a project inquiry, buyers can review the available fastener product categories to […]

How Should Buyers Evaluate Self Tapping Screws for Project Procurement?

How Should Buyers Evaluate Self Tapping Screws for Project Procurement?

#4 self tapping screws should not be purchased from the “#4” designation alone. For a usable B2B specification, the buyer still needs the actual screw diameter, thread form or pitch, overall length, substrate, pilot-hole condition, head and drive style, material, surface finish and quantity. This matters because suppliers may use different naming systems. Wotu Fastener’s […]

Which Self-Tapping Roofing Screw Specification Fits Metal Panels on Steel or Timber?

Which Self-Tapping Roofing Screw Specification Fits Metal Panels on Steel or Timber?

The correct self-tapping roofing screw depends on the complete panel-and-substrate stack-up. Steel supports typically require a point and thread matched to the support thickness and any pilot-hole requirement; timber supports require a wood-appropriate thread and sufficient embedment. In both cases, buyers must define diameter, length, head, sealing washer, material or coating, environment, pull-out requirements, and […]

Frequently Asked Questions

What information should a size chart show before I use it for purchasing?

It should show the thread system, nominal diameter, pitch or thread designation, length, drive size, point style, and the standard the dimensions follow. If the chart only lists diameter and length, it may be enough for rough identification but not enough for a confident order.

Is a cup point always the safest choice for holding a shaft?

No. A cup point often gives strong grip because it bites into the mating surface, but it can mark the shaft. A flat point or nylon-tip screw may be better where the surface must remain clean, while a cone or dog point may suit assemblies designed with a matching recess or locating feature.

Can I replace a missing grub screw by measuring the hole?

Measuring the threaded hole helps, but it may not identify the full specification. You still need to confirm the thread pitch, required length, drive type, and point shape so the replacement tightens correctly and contacts the part in the intended way.

Why do two screws with the same diameter and length perform differently?

The point geometry, material, hardness, finish, and drive quality can change how the screw grips, resists loosening, and survives repeated installation. A size chart gives the dimensional starting point, but the application decides the point style and material requirements.

What should I send with an inquiry if I need a PDF chart matched to my parts?

Send the required standard or drawing if you have one, plus the thread size, length, point style, drive type, material, finish, and application. If you are replacing an existing part, include a clear photo and measured sample details so the supplier can check the specification more accurately.

Related Search

allen bolt size chart pdf allen grub screw allen bolt size chart #8 wood screw drill bit size 1 inch screw 4 screw 8mm anchor bolt drill size 5mm screw 1 screw 8mm screw

Leave Your Message

Send the required thread size and length, point style, and material or finish. If available, include the drawing, standard, or a photo of the existing grub screw.