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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:Pancake Head Machine Screw
Materials:Carbon Steel
Surface treatment:Nickel Plated
Head Type:Low Head
Drive:None
Thread:Half Machine Thread
Point:Blunt
Forming:Single Die Heading
Size:M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M14
Number:848
We make pancake head machine screws from carbon steel with a flat disc head, no drive recess and a half thread, nickel plated and quoted from M1 to M14. Head diameter and flatness, thread position and plating come from your drawing, and the first article is fitted into your joint with its mating nut.
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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.
A pancake head machine screw is a machine screw with a very wide, very flat disc head and no drive recess at all, so it is turned from the opposite end rather than from the head. The recorded item on this page is nickel plated carbon steel with a low head and a half machine thread, quoted from M1 to M14 with Number 848.
Pancake head. A disc, not a dome: the top is flat, the edge is short and the bearing face is a full annulus. It sits on a surface with almost no height above it, which is the whole reason the form exists.
No drive. There is no slot, no cross and no socket in the top. The screw is tightened by turning a nut on the other end, by gripping the plain shank, or by hand into a thread that is already formed.
Half machine thread. Thread from the point to a defined position, with a plain shank under the head. The plain length passes a clearance bore without cutting it and gives a surface to hold if the part is turned by the shank.
Nickel plated steel. A hard bright deposit that keeps a flat face even, which is what a head this visible needs, and that adds only a few microns to a thread that has no recess to tighten.
The head is formed and then flattened to a disc, and there is no recess operation at all. That is the structural fact of this part: the die that makes it is simpler than a cross or a slot die, and the head it leaves has the full material of the disc available to resist bending.
The absence of a drive is a design statement, not an omission. A head with no recess can be made thinner than any driven head of the same diameter, because a recess needs material around it. On a pancake head machine screw the flat top is the functional face — it is what a label sits on, what a cover slides over, or what has to disappear under a film.
The installation is therefore defined by the joint, not by the screw. If the part is a bolt-like fixing, the nut on the other end does the turning and the head simply bears. If it is a hand-driven screw, the thread in the hole has to be formed first and the joint is only ever finger-tight. Both are legitimate, and the drawing should say which one the part is for.
The half thread supports that. The plain shank is a grip surface if the screw is turned by hand or by a collet, and it is a clearance surface if the screw passes through a plate before the thread bites lower down. On a pancake head machine screw the thread position is a handling dimension as well as a clamping one.
Nickel goes on last. There is no recess to narrow, which removes the usual plating argument, but the flat top still shows every variation in the deposit, so the face is judged as a colour sample rather than only as a dimension.
The family is quoted from M1 to M14, with M1, M2, M3, M4, M5, M6, M7, M8, M9, M10 and M14 in the recorded range. Custom lengths up to 2,000 mm are subject to DFM review after drawing submission; on a pancake head machine screw the head diameter and the thread length are quoted independently of the overall length.
| Item | How it is defined | What we control |
|---|---|---|
| Head | Pancake, flat disc | Diameter, height and face flatness |
| Drive | None, by design | Face left clean and flat |
| Thread | Machine thread, half length | Thread length and position from the end |
| Shank | Plain, under the head | Diameter and surface for grip or clearance |
| End | Blunt, chamfered | Chamfer cut, not deburred |
| Length | From under the head to the end | Measured on the shop plate |
Head height is the dimension that matters and the one that is hardest to hold. A disc has no dome to hide a variation, so a head that is two hundredths thicker at the rim is visible as a rock, and on a part that has to sit under a label that rock becomes a lump in the film.
Thread length is quoted from the end. On a screw that is turned from the far end, the plain shank is also the grip surface, so its length and its finish are functional: a shank with a roll mark on it will not release cleanly from a collet, and a shank that is short leaves nowhere to hold.
Three features define a pancake head machine screw: the flat disc, the absent drive and the half thread. Together they describe a part that is installed by the joint rather than by the head, and that changes what the drawing has to specify.
| Feature | What it gives | What it costs |
|---|---|---|
| Flat disc | Almost no height above the surface | No recess possible; nothing to drive |
| No drive | Clean visible face, full head material | Installation depends on the nut or the grip |
| Half thread | Grip or clearance under the head | Thread position must be specified |
| Nickel plate | Even bright face | Not sacrificial; scratches show |
| Blunt end | Starts in an existing thread | Needs a tapped nut or hole |
The three ways to install one are worth separating. A nut on the far end does the work, and the head only bears; that is the classic bolt configuration and it needs no drive at all. A collet or a soft-jaw chuck can grip the plain shank and turn the screw, which is how a part like this is fitted on a machine. And fingers can turn it into a thread that has already been cut, which is how a cover screw with a decorative flat top is fitted.
What none of those options allows is torque at the head. A pancake head machine screw cannot be tightened by a driver, so the clamp load comes from the nut or from the fingers, and the joint has to be designed around that. Where more torque is needed, the part needs a drive — and that makes it a different screw.
The recorded finish is bright nickel. On a flat disc the whole top is seen at once, so an even tone is the requirement and nickel is the coating that delivers it without the granular look of a zinc deposit.
| Finish | How it protects | Effect on head and thread | Typical use |
|---|---|---|---|
| Bright nickel | Hard barrier deposit | A few microns; face checked even | Visible covers and panels |
| Black nickel | Dark nickel deposit | A few microns; face re-checked | Dark visible housings |
| White zinc | Sacrificial zinc | A few microns; thread re-checked | General indoor work |
| Black oxide | Thin conversion film, oiled | Almost no change | Unseen joints |
| Stainless, plain | Passive chromium oxide film | None; gauged as formed | Washed and damp assemblies |
Nickel is a barrier rather than a sacrificial coating. On a flat head that is handled, the wear appears as a dull patch in the middle of the face rather than at the edge, because that is where fingers and cloths land. Once the deposit is broken, the steel at that patch rusts, and on a flat face a rust patch is more visible than a scratch on a dome.
The thread is where plating has a practical effect. A machine thread with a nut on it is less sensitive than a formed thread, but the plating still changes the fit, so the thread is gauged after plating and the nut is run on as part of the first article.
Three assemblies where a flat head with no drive is the right answer:
| Where it sits | The screw holds a cover that slides over or past the fixing, so nothing may stand above the surface and nothing may catch. |
| When it goes wrong | A driven head stands proud and the cover rides on it, wearing a track in the panel and loosening the joint. |
| Why it happens | The part moves over the fixing, and the surface has to stay clear. |
| What we control | Head height and face flatness checked, thread position measured. |
| Where it sits | The screw fixes a plate under a label, a film or a decorative face where the head must not show as a bump. |
| When it goes wrong | A dome or a recess shows through the film, and a slot fills with adhesive. |
| Why it happens | The face is covered after assembly, and the fixing is under it. |
| What we control | Face flatness checked on the first article, plating tone held to the sample. |
| Where it sits | The screw fixes a fitting through a panel where the head has to sit flush on a visible face and the joint is closed from the other side with a nut. |
| When it goes wrong | A head that stands proud marks whatever is stacked against it, and a recess collects dust and polish. |
| Why it happens | The face is visible, the joint is closed from behind, and the fixing is decorative as well as structural. |
| What we control | Thread gauged, head diameter matched to the fitting, face checked flat. |
Four reasons that matter on a disc head with no drive, each tied to what the drawing has to prove:
|
Head face and thread reviewed together
The head diameter, the head height and the thread position are reviewed as one set, so a head that would rock or a shank too short to grip is raised before the die is cut. Basis: Head face and thread reviewed as one set. |
Heading, flattening and rolling in one route
The head is formed and flattened, the half thread is rolled to a blunt point and the parts are nickel plated in one route. Basis: One route from wire to plated screw. |
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Face and threads checked on the part
The head face is checked for flatness on the projector, the thread is gauged, and the nut is run on as part of the first article. Basis: First article checked with the mating nut. |
First article fixes the setting
The first article fixes the wire heat, die set, flattening height and plating; repeat orders are compared against that record. Basis: First article signed off before the batch is released. |
Shi Shi Tong forms these pancake head machine screws from carbon steel wire on single-die headers that upset the disc head, flattens the head to its drawing height, rolls the half thread to a blunt chamfered end and nickel plates the parts. The first part of every run is measured on the head, checked for face flatness, entered into a thread gauge and run with its mating nut before the batch continues.
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Flattening a head with no recess is more sensitive than flattening one with a recess, because there is nothing to conceal a variation. The die has to hold the rim and the centre at the same height, and a worn die leaves a disc that is slightly dished, which shows on a flat face as a ring of contact and a joint that rocks. The face is checked on the projector at the rim and at the centre.
What decides whether pancake head machine screws pass is the head face, the head diameter, the thread, the plain shank and the plating. The inspection agreement covers those, and the criteria come from the drawing.
Head face and diameter on the projector |
Thread gauged after plating |
Hardness testing against the property class |
Salt-spray testing of the nickel plate |
The head face is checked for flatness at the rim and at the centre, and for diameter. Flatness is the whole specification on this part: a disc that is dished shows on a flat panel as a ring of contact and a joint that rocks under load, and there is no dome to hide it.
The thread is gauged after plating and the mating nut is run on. A machine thread with no drive has to be usable with a nut from the far end, so the nut is the check that matters, and it is run on the sample rather than assumed from a gauge.
The plain shank is measured where the drawing makes it functional — either as a grip surface for a collet or as a clearance diameter for a plate — and checked for roll marks, which matter if the shank is gripped.
Every shipment of pancake head machine screws is traceable to the wire it was made from and to the plating batch. The grade and heat number are recorded 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 batch we supply the material certificate, the inspection record for the criteria on the drawing and, where it is listed, the third-party report for the material or the plating. The documents carry the drawing revision and the batch number, so the paperwork can be matched to the parts.
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 a head with no drive the first article is also fitted into the customer’s joint, because how the part is held and turned is part of the specification. Buyers visit during the process to review samples and to see how the heads are formed.
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8,678+
customers served
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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 plating 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 |
From the other end. Either a nut does the turning and the head only bears, or the plain shank is gripped in a collet, or it is turned by hand into a thread that already exists.
So the head can be made thinner than any driven head of the same diameter, and so the face stays clean for a label, a film or a sliding part.
Only by the same route it was fitted. With a nut on the far end it can be serviced normally; pressed or hand-fitted, the joint is not meant to come apart often.
Whatever the nut or the fingers apply. The head cannot accept a driver, so the joint is designed for the clamp load the nut can produce rather than for the head.
It has to be flat. A dished disc bears on a ring and rocks, and on a visible face that shows immediately. Flatness is the specification on this part.
Head diameter and height with a flatness note, thread size and length with its datum, plain shank diameter and length, overall length, and the material and plating.
How a pancake head machine screw project runs from drawing to repeat delivery:
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1
Send the drawing and the joint it fits
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→ |
2
Head face, thread and shank review
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→ |
3
First article fitted into your joint
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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 head diameter and height, any flatness requirement, the thread size and length with its datum, the plain shank dimensions, the overall length, the material and the plating.
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Head diameter
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Head height
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Thread and datum
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Shank dimensions
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Overall length
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Material and plating
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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
