Tel：
+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
Place of Origin:Guangdong,China(Mainland)
Brand Name:Shi Shi Tong
Materials:Stainless Steel
Surface treatment:Plain stainless, passivated; no coating over the cross, slot or knurl
Thread:Machine thread
Point:Plain, chamfered
Forming:CNC turning from bar; cross and slot cut; knurl rolled
Size:M6*22.5mm,Diameter 14mm
Head Type: Cup Head
Drive Type:Phillips Slot Combination Drive
We turn stainless Phillips slot combination screws with a low cup head, a knurled collar and a shoulder, quoting both recess depths to the drawing. The cross and the slot share one shallow head, so each is half as deep as it would be alone and the torque ceiling belongs to the recess, not the thread.
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.
A Phillips slot combination screw carries two drives in one head: a cross recess and a single slot cut through it, so either a Phillips bit or a flat blade will turn it. This part is stainless steel with a low cup head, a knurled collar under the head and a shoulder below it, and is quoted to the drawing.
Combination drive. A cross and a slot in the same head, so two kinds of tool will fit.
Low cup head. A shallow cylindrical head that keeps the fixing close to the surface.
Knurled collar. Serrations under the head, so the part can also be gripped or pressed rather than driven.
Shoulder. A locating diameter below the head that holds the parts in line.
They are used in camera hardware, instruments and small assemblies where a service kit may hold a blade rather than a bit, and where the joint is sometimes made by hand.
A phillips slot combination screw is a compromise cut into a head that was already thin. The cross is formed first and the slot is cut across it, and because the low cup head has little height, both features are shallow. A Phillips cross needs a certain depth to hold a bit without climbing out; a slot needs depth to keep a blade from rocking. Put the two in the same shallow head and each gets about half of what it would like.
On a phillips slot combination screw that is not a defect; it is what the part is for. A combination drive lets one fixing be opened with whatever tool is in the kit, and in exchange it accepts that neither tool will carry a high torque. The cross does the driving when a bit is available, the slot is there for a blade, and the joint is designed so that neither has to reach the limit.
On phillips slot combination screws the knurled collar adds a third way to turn it. Serrations under the head give fingers a purchase for a final hand-tight turn, and in a moulded or pressed joint the knurl can bite the material so the part does not rotate while a nut is fitted. That is a second load path that does not depend on the recess at all.
On a phillips slot combination screw the low head is what makes the knurl matter. Because the head is shallow, there is less to grip with a tool and less depth for the recess, so the collar becomes the feature that lets an assembler finish the joint by hand rather than fighting a shallow cross.
Below the collar on a phillips slot combination screw, the shoulder locates. It is a smooth diameter that passes through the part and holds it in line, which is the reason a shoulder screw is chosen over a plain screw in the first place. The thread at the end takes the nut, and the head and collar sit on the near face.
Together the features describe one kind of joint: a small, visible fixing, assembled by hand or with a light driver, located on a shoulder, and locked at the far end. Specified that way, the part behaves; specified as a high-torque fastener, the recess is the first thing to fail.
Phillips slot combination screws are quoted by shoulder diameter and length, thread size and pitch, head diameter and height, cross size and depth, slot width and depth, knurl and finish. Custom lengths up to 2,000 mm, subject to DFM review after drawing submission. The quotation carries the material, the head, both drives, the knurl, the thread and the finish.
| Item | How it is defined | What we control |
|---|---|---|
| Shoulder | Diameter and length | Fit and roundness |
| Head | Low cup head | Diameter and height |
| Cross | Phillips | Size and depth |
| Slot | Single slot through the cross | Width, depth and end radius |
| Knurl | Collar under the head | Diameter, tooth count and depth |
| Thread | Machine thread | Size, pitch and length |
On phillips slot combination screws both recess depths are written, because they compete for the same material. A slot cut a little deeper than the cross leaves the cross without a floor; a cross cut deeper leaves the slot with thin walls.
On phillips slot combination screws the knurl is dimensioned by its outside diameter and tooth count. It is a grip feature, so its diameter is what the fingers or the moulded boss see, and it has to be inside the head diameter so it does not stand proud of the face.
The shoulder is measured on the finished part and its length is the span the parts occupy. On this form the collar sits between the head and the shoulder, so the length is measured from the collar face rather than from the top of the head.
Four properties decide this part, and each carries a cost:
| Property | What it gives | What it costs |
|---|---|---|
| Combination drive | A blade or a cross bit will work | Each drive is shallower than a single one |
| Low cup head | A fixing close to the surface | Little height for either recess |
| Knurled collar | A hand grip and a press fit | Another feature in the same small head |
| Stainless body | No coating, no rust | Galls against stainless in a nut |
The value is a fixing that almost any tool kit can open, on a head that stays low and a shoulder that locates the joint, in a material that will not rust on a camera or an instrument.
The cost is that the recess is the weakest part of the part, so the torque ceiling is low and the joint is designed around that rather than around the thread.
The recorded finish on these phillips slot combination screws is stainless steel, supplied plain and usually passivated. There is no coating to fill the cross, the slot or the knurl, so all three features are exactly as machined, which matters because each of them is small.
| Option | How it protects | Effect on the drives | Typical use |
|---|---|---|---|
| Passivated stainless | Clean, thickened oxide | No build; both drives as cut | Instruments and camera gear |
| Plain stainless | Natural oxide | No build | Machined and deburred parts |
| Black oxide | Conversion layer | Very thin; cosmetic | Dark hardware |
| Dry film lubricant | Low-friction film | Thin; eases the thread | Joints opened often |
| Nickel plated | Hard barrier layer | Builds; both drives re-checked | Bright decorative finish |
A plated version of this head is worth checking carefully. The knurl and the two recesses are all small features, and a coating that builds in one of them changes how the part feels before it changes how it looks.
Plain stainless needs no protection and leaves the knurl crisp, which is why it is the usual finish on camera and instrument hardware.
Three products where two tools and a hand grip all help:
| Where it sits | The screw locates a plate or an arm and is adjusted on set with whatever tool is to hand. |
| When it goes wrong | The cross rounds because a shallow recess was driven hard, or the plate shifts. |
| Why it happens | The head is low and the cross is shallow, and the joint expects too much torque. |
| What we control | Head height and both recess depths agreed; sample driven with a bit and a blade. |
| Where it sits | The screw fixes a sub-panel that is assembled by hand and serviced with a blade. |
| When it goes wrong | The knurl slips in the fingers, or the slot widens. |
| Why it happens | The collar is too small to grip, and the slot is used as a drive. |
| What we control | Knurl diameter and tooth depth set for fingers; sample turned by hand. |
| Where it sits | The screw presses into a boss and takes a nut from the far side. |
| When it goes wrong | The part rotates in the boss while the nut is fitted. |
| Why it happens | There is no counter-hold, and the knurl is too shallow to bite. |
| What we control | Knurl bite checked in the boss; sample assembled without a counter-hold. |
Four points that decide whether both drives and the knurl survive assembly:
|
Both recess depths written
The drawing carries the cross depth and the slot depth, because the two compete for the same material in a low head. Basis: Drives share the head on purpose. |
Cut, knurled, then gauged
The cross, the slot and the knurl are cut to size and checked with the tools after the finish. Basis: Tools fit the finished part. |
|
Turned three ways
The first article is driven with a blade, driven with a bit, and turned by hand on the knurl. Basis: All three proved. |
Same head every lot
Head height, both depths and the knurl are recorded with the drawing revision, so a repeat batch feels the same. Basis: Same feel across lots. |
A combination head is easy to make and easy to make badly, because three features share one small head. These four points are what keeps them from stealing from each other.
These screws are turned from stainless bar: the low cup head and the knurled collar are formed, the shoulder is turned, the cross is cut and the slot is cut across it, and the thread is cut or rolled. The first piece of every run is measured on head and collar, both recesses, shoulder, thread and length.
|
|
On phillips slot combination screws the sequence matters. The cross is cut first and the slot second, because the slot has to pass through the centre of the cross; doing it the other way leaves the cross off-centre and the bit climbing out on one side.
The knurl is cut before the head is finished, so the collar sits under a clean face. A knurl cut after the head has been faced tends to leave a burr at the edge, and on a stainless part that burr is felt in the hand long before it is seen.
Stainless work-hardens at the cut on phillips slot combination screws, so both recesses are finished with light passes. A torn crest inside the cross is what makes a bit feel loose, and it cannot be corrected after the part is finished.
What decides whether a batch of combination screws passes is the cross that takes a bit, the slot that takes a blade and the knurl that takes a hand, plus the shoulder that locates the joint.
Head and recesses on the projector |
Thread checked with gauges |
Material checked |
Salt-spray testing where required |
The cross is measured for depth and width and driven with the bit; the slot is measured and driven with the blade. Both are tested on the same part, because the usual failure is that one was cut deeper than the other and left the second with a thin floor.
The knurl is checked for diameter, tooth count and depth, and turned by hand. A knurl that is too shallow does not grip, and one that is too deep cuts the fingers on a camera plate.
The shoulder is measured at two points and the length from the collar face. A shoulder a few hundredths over will not enter the bore, and the part is then blamed for a fault in the fit rather than in the drive.
Every batch of combination screws is traceable to the bar it was made from. The material certificate states the grade, the heat number, the chemistry and the mechanical properties, and the inspection record carries the head, both recesses, the knurl, shoulder and thread.
ISO 9001:2015 |
RoHS test report |
Registered trademark |
Patent: security screw and driver |
With each shipment we supply the material certificate and the inspection record for the head, recesses and shoulder. The records carry the batch number, so a repeat order can be compared with the first on the three features that decide how the part is driven and held.
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 combination head the first article is driven all three ways, because a part that takes one tool and not the others has lost the reason for the combination. Buyers visit during the process to review samples.
|
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 turning cells 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 |
So a blade or a cross bit will turn it, whichever the kit holds. The trade is that both are shallower than a single drive.
The cross, when a bit is available. The slot is the fallback for a blade.
A hand grip for a final turn, and a bite in a moulded boss so the part does not rotate while a nut is fitted.
A low head gives less depth, and a worn bit or a hard drive uses it up. It is the weakest feature on the part.
No. Design the joint around the recess, not the thread.
Shoulder diameter and length, head and collar, cross and slot sizes with depths, thread, and the finish.
How a combination screw project runs from drawing to repeat delivery:
|
1
Send the drawing and the bore sample
|
→ |
2
Head, drives and knurl agreed
|
→ |
3
First article driven three ways
|
→ |
4
Batch production and repeat orders
|
Each step is confirmed with you before the next one starts; the drawing revision used for the first article is what repeat orders are checked against.
For a quotation, send the drawing with the shoulder diameter and length, head and knurl, cross and slot sizes with depths, thread and finish.
|
Shoulder
|
Head
|
Cross
|
|
Slot
|
Knurl
|
Thread
|
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
