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+86 13143444311
Email：sst@szsst88.com
Fax：+0086-755-27322278
Address：Building 9, First Industrial Zone, Tantou Industrial City, Songgang Street, Baoan District, Shenzhen 518105, Guangdong, China
Type:m5 countersunk machine screws
Materials:Stainless Steel
Surface treatment:Plain
Head Type:Flat Head (CSK)
Drive:Six-lobe star recess (Torx)
Thread:M5 x 0.8 machine thread
Point:Plain, chamfered
Forming:Single Die Heading
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
We make M5 countersunk machine screws in stainless steel with a 90-degree cone and a six-lobe recess, to the length on your drawing. Cone angle, head thickness, star size and thread come from your drawing, and the first article is seated in your own countersink.
Watch the factory video·Email sst@szsst88.com
ISO 9001:2015 · Manufacturing since 1998 · 8,678+ customers · 89 countries and regions
Made to order – there is no stock catalogue. Each part is produced to your drawing, and production starts after drawing review and first-article approval.
M5 countersunk machine screws are 5 mm metric machine screws with a 90-degree countersunk head, driven with a star key and finished flush with the surface. The part recorded here is stainless steel, passivated, with a six-lobe recess.
M5 thread. 5 mm nominal diameter with a 0.8 mm standard pitch, taking a tapped M5 hole or an M5 nut.
Countersunk head. A cone of about 10 mm diameter that seats in a matching countersink and leaves no edge above the panel.
Six-lobe recess. A star socket at the T25 to T27 end of the range, driven with a star key rather than a hex key.
Passivated stainless. A2 grade, no coating, so the cone and the recess are as formed.
M5 countersunk machine screws are the size used on brackets, hinges, covers and medium-duty panels: large enough to carry a real clamp, small enough to sit in a 10 mm countersink without a washer, and common enough that the key is on every bench.
For M5 countersunk machine screws the size is where the part stops being a detail fastener. At M3 and M4 the head is small, the recess is shallow and the joint is usually a cover; at M5 the head is about 10 mm across, the cone removes a ring of material from the panel, and the clamp the thread can carry is enough to distort thin sheet if the seat is not right.
That makes the countersink depth the first consideration on M5 countersunk machine screws. The cone has to be cut to a depth that lets the head sit level, and the material left under the cone is what the thread holds; on a 1.5 mm panel an M5 head takes a noticeable share of the thickness, and on a 1 mm panel there is very little left. Where the panel is thin, a pan or truss head at the same thread is the honest choice, and the change is a design decision rather than a finishing one.
On M5 countersunk machine screws the drive is the second consideration. At M5 the six-lobe recess is large enough to take real torque — T25 or T27 depending on the standard the head is made to — and a star key of that size does not cam out the way a cross recess would. That is why this size is often specified with a star recess even when the rest of the assembly uses cross-headed screws.
The third consideration on M5 countersunk machine screws is the joint they sit in. M5 is the size a hinge, a bracket or a clamp is built around: the load is real, the joint is often adjusted, and the screw is expected to come out and go back in without the head being ruined. A countersunk head gives the flush face; the star recess gives the drive the joint needs.
Stainless completes the picture on M5 countersunk machine screws. An M5 stainless screw holds its finish, does not need a coating that would fill the recess, and works in damp or washed areas where a plated screw would rust at the cone. The trade is galling in aluminium and a softer head than a hardened key, so the assembly discipline matters more at M5 than the material choice suggests.
The size is fixed: M5. Lengths are made to the drawing, and custom lengths up to 2,000 mm are subject to DFM review after drawing submission. For M5 countersunk machine screws the quotation carries head diameter, cone angle and head thickness, the star size and recess depth, thread pitch and overall length.
| Item | How it is defined | What we control |
|---|---|---|
| Thread | M5 x 0.8 | Pitch, length and start position |
| Head | Countersunk, 90-degree cone | Diameter about 10 mm, angle, thickness and rim |
| Recess | Six-lobe star, T25 to T27 | Size, depth, lobe form and floor |
| Length | Overall, head included | Length tolerance and thread start |
| Material | A2 stainless | Grade and heat number on the certificate |
| Finish | Passivated, plain | Surface condition and recess edges |
On M5 countersunk machine screws head diameter and cone angle belong together on the drawing. At M5 the countersink is large enough that an angle mismatch shows at the rim, and on a flush panel it is visible from a metre away.
On M5 countersunk machine screws the star size is worth naming for the same reason: the same head diameter can be cut for T25 or T27, and a key that is one size off will ream the lobes rather than turn the screw.
Four features define this size, and each one is a trade:
| Feature | What it gives | What it costs |
|---|---|---|
| M5 thread | Real clamp for brackets and hinges | Takes a share of thin panel thickness |
| Countersunk head | Flush, self-centring face | Cone removes material where the thread holds |
| Star recess | Torque without cam-out | Star key of the right size required |
| Stainless body | Finish as made; damp-service ready | Galls in aluminium; softer than the key |
| Passivated finish | Cone and recess as formed | Marks show on a bright head |
The value of M5 countersunk machine screws is a joint that disappears and still takes load. A hinge plate or a bracket fixed with M5 countersunk screws sits flush, can be shimmed and refitted, and takes the torque the joint needs — which an M3 or M4 screw of the same head form would not.
The cost on M5 countersunk machine screws is the panel. At M5 the countersink is a real cut into a light-gauge sheet, and a joint designed without allowance for it will strip or dish before the screw is tight.
The recorded finish on M5 countersunk machine screws is passivation on A2 stainless with no coating. At M5 that keeps the cone at its cut angle and the star recess at its cut depth, which matters because both are contacting features: a coating on the cone changes where the head seats, and one in the recess changes how the key sits.
| Option | How it protects | Effect on cone and recess | Typical use |
|---|---|---|---|
| A2, passivated | Passive chromium oxide film | Cone and recess as formed | Brackets and hinges |
| A4, passivated | Passive film with molybdenum | Cone and recess as formed | Marine and chlorinated |
| A2, electropolished | Thicker passive film, bright | Edges rounded; recess checked | Visible hardware |
| Steel, zinc plated | Sacrificial zinc | Build at cone and recess; re-checked | Indoor general work |
| Steel, black oxide | Conversion film, oiled | No measurable build | Dark equipment |
Where the joint is indoors and the screw is hidden, plain A2 is the simple answer. Where it is in chlorides — a boat, a pool plant, a food line — A4 is the grade, and at M5 the cost difference is small against a joint that has to be rebuilt after a season.
Where a plated steel M5 is used, the cone is the feature to check after plating. A zinc layer on a 10 mm cone changes the contact ring measurably, and a head that was flush before plating can sit proud afterwards.
Three assemblies where this size is the standard:
| Where it sits | The screw fixes a hinge leaf or a bracket where the head must finish flush so the moving part clears it. |
| When it goes wrong | A proud head catches the hinge leaf and the door drags. |
| Why it happens | The joint is flush, the load is real, and the panel is a few millimetres thick. |
| What we control | Cone angle and head thickness checked; first article fitted in the hinge. |
| Where it sits | The screw holds a guard where the face is slid across and the head must not interfere. |
| When it goes wrong | The head stands a few tenths proud and rubs a line in the mating panel. |
| Why it happens | The face is functional, the seat is machined, and the joint is serviced. |
| What we control | Flushness checked on the assembled joint; first article fitted and cycled. |
| Where it sits | The screw fixes a cleat or a bracket where salt or rain is present and the head is visible. |
| When it goes wrong | A plated screw rusts at the cone and the stain runs down the fitting. |
| Why it happens | The joint is exposed, the size is structural, and the head is flush. |
| What we control | Grade and passivation confirmed; first article fitted and left exposed. |
Four reasons that matter at this size, each tied to something the drawing has to prove:
|
Cone, thickness and recess agreed
Cone angle, head thickness and star size are agreed as a set, because at M5 all three come out of the same head and each limits the others. Basis: Cone, thickness and recess agreed. |
Formed, recessed and passivated in one route
The cone and star recess are formed in one stroke, the thread rolled and the parts passivated as a batch. Basis: One route from wire to passivated screw. |
|
Recess proved with the star key
The recess is proved with the production star key at the joint torque, because at M5 the key is large enough to damage a shallow socket. Basis: Recess proved with the key. |
First article in your countersink
The first article is seated in the customer countersink, because flushness at this head size is a property of the pair. Basis: First article seated in the countersink. |
These screws are headed on single-die machines that form the 90-degree cone and cut the six-lobe recess in one stroke, rolled with the M5 thread and passivated as a batch. The first part of every run is measured on head diameter, cone angle, head thickness, recess depth and thread.
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On M5 countersunk machine screws the head is big enough to give the punch room, and that changes the risk. The failure is less likely to be a thin recess floor and more likely to be cone angle drift or a star recess cut slightly off centre, both of which let the head rock or the key load one side. The first part of every run is checked against a countersink master rather than a sample of the screw alone.
Rolling the M5 thread is the second control. The thread runs to the length the drawing sets and stops clear of the head; on a countersunk screw the thread start and the cone are close together, and a thread that runs into the cone changes where the head seats.
What decides whether M5 countersunk screws pass is the cone, the recess, the head thickness and the thread. The inspection agreement covers those, and the criteria come from the drawing.
Cone and recess on the projector |
Thread and start checked |
Core hardness checked |
Salt-spray testing of the grade |
Cone angle is measured against a master and proved on a countersink block, and head thickness is measured in the same pass, because recess depth only means anything against it. The recess is proved with the production star key, and the thread is gauged after passivation.
A sample from every batch is seated in the customer countersink and driven to the joint torque, then removed. At M5 that cycle is the check that matters, because the head is large enough to mask a rock until the joint is loaded.
Every batch is traceable to the wire it was made from and to the passivation batch that finished it. The grade and heat number appear on the material certificate supplied with the parts, and the inspection records follow the criteria agreed on the drawing.
ISO 9001:2015 |
RoHS test report |
Registered trademark |
Patent: security screw and driver |
With each shipment we supply the material certificate, the inspection record for the dimensions on the drawing and, where the grade is listed, the third-party report that covers it. The documents carry the drawing revision and the batch number, so a repeat order keeps the same cone and the same recess.
More than 8,678 customers in 89 countries and regions have ordered from Shi Shi Tong; 87% of orders come from repeat customers and 56% through referrals. Most projects follow the same route: drawing review, first-article approval, then batches checked against that sample. On M5 countersunk screws the first article is seated in the customer countersink, because flushness at this head size is a property of the pair. Buyers visit during the process to review samples.
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8,678+
customers served
|
87%
of orders from repeat customers
|
56%
of orders through referrals
|
89
countries and regions shipped to
|
Buyers and quality engineers visit for sample review, process discussion and supplier audits; the visit is arranged around production so the headers and the passivation line can be seen on the day the parts run.
Customer group visit – sample review |
Customer group visit – process discussion |
Customer group visit – factory tour |
Customer visit – project kick-off |
Danish customer – drawing review |
Industry exhibition – meeting customers |
0.8 mm standard. A tapped M5 hole or a standard M5 nut takes it; fine-pitch variants exist and should be stated on the drawing.
T25 or T27 depending on the head standard it was made to. Name the size on the drawing so the key matches.
Usually a cone angle mismatch: a 90-degree head in an 82-degree countersink contacts on a ring instead of its face.
Barely. The countersink removes much of the thickness, so a pan or truss head at M5 is often the better joint.
A2 covers rain, A4 covers salt and chlorides. With no coating, the cone and recess stay as formed.
Cone angle, head diameter and thickness, star size and depth, thread pitch and overall length.
How an M5 countersunk screw project runs from drawing to repeat delivery:
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1
Send the drawing and the countersink
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→ |
2
Cone angle and star size agreed
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→ |
3
First article seated in your part
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→ |
4
Batch production and repeat orders
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Each step is confirmed with you before the next one starts; the drawing revision from the first article is what repeat orders are checked against.
For a quotation, send the drawing with the cone angle, head diameter and thickness, star size and depth, thread pitch and overall length.
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Cone angle
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Head diameter
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Head thickness
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Star size
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Thread pitch
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Length
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Sending a drawing? The form below does not take attachments. Email the PDF, DXF or STEP file to sst@szsst88.com with the part name and quantity in the subject line – the drawing is reviewed and a quotation follows.
+86 13143444311
sst@szsst88.com
