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
Materials:Titanium
Surface treatment:Plain
Groove Type:Slotted
Head Type:Flat head, slotted
Drive:Slotted
Thread:Machine thread, internal in the barrel
Grip range:Set for the compressed leather thickness
Forming:CNC turning from bar; barrel drilled and threaded
Size:M2-M10
Number:32
We make chicago screws for leather belts in titanium, a matched post and barrel with slotted flat heads, quoted with the grip set for the compressed leather thickness. Leather settles under the heads, so a pair sized from the new material is tight on day one and loose by the end of the season.
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.
Chicago screws are two-piece posts with a flat head on each side, screwed together through the material. In leather work they replace stitching and rivets where the joint has to be removable. This pair is titanium with slotted flat heads, supplied plain, and is quoted with the post and barrel lengths made to the drawing.
Two pieces. A male post with a thread and a female barrel, so the joint can be opened without cutting.
Slotted flat heads. Wide discs that sit on the leather and take a blade for the final turn.
Titanium body. No rust and no staining of the leather, even on a belt worn daily.
Plain finish. The natural oxide, with nothing to wear off onto the material.
They are used on belts, straps, bags, harness and watch straps: anywhere a thick, flexible material needs a joint that can be taken apart and put back, and where a rivet would make the repair impossible.
Leather is not a plate. It is a compressible, slightly elastic material, and when the two heads of a chicago screw are drawn together, the leather under them compresses by a noticeable fraction of its thickness. A pair that is exactly right on a new belt sits a little loose after a month of wear, because the material has settled and the heads have moved closer together with nothing left to take up the slack.
That changes how the part is sized. The grip is set from the compressed thickness, not from the nominal one, and the post length carries a margin so the barrel still has thread engaged when the leather has settled. Setting the length from the new leather thickness produces a pair that is tight on day one and loose by the end of the season.
On chicago screws the hole matters as much as the length. A punched hole has a clean, slightly compressed edge and grips the post along its full circumference; a drilled hole is often a fraction larger and a little ragged, and the post can rotate inside it. On a belt that means the heads turn against each other in use, and a slotted head slowly wears a ring into the leather.
On chicago screws the head diameter does the rest. Leather stretches locally, so a small head pulls into the material and leaves a dimple; a wide head spreads the load and keeps the surface flat. Titanium lets the head stay thin and still hold its shape, which on a strap is the difference between a fixing and a dent.
The slotted head is there for the final turn and for holding one side while the other is turned. It is not a drive for high torque: the leather will compress further, not tighten, and over-turning simply pushes the heads into the material.
So the specification has three parts: the compressed thickness, the hole, and the head. Chicago screws that satisfy all three feel correct in the hand; ones that do not are either loose or dimpled, and both are blamed on the leather.
Chicago screws are quoted by post diameter and length, barrel diameter and internal thread, head diameter and thickness, slot width and depth, material and finish. Custom lengths up to 2,000 mm, subject to DFM review after drawing submission. The quotation carries the material, both halves, the heads and the finish.
| Item | How it is defined | What we control |
|---|---|---|
| Post | Diameter and length | Thread length and run |
| Barrel | Diameter and thread depth | Engagement inside the barrel |
| Heads | Diameter and thickness | Bearing area on the leather |
| Slot | Width and depth | Blade fit and end radius |
| Grip | Compressed material thickness | Set by the two lengths |
| Material | Titanium | Grade and surface condition |
The grip is written as a range, with the compressed thickness at the lower end and a margin at the upper. Writing a single length leaves the settlement out, and the settlement is what the customer notices.
The barrel depth is the dimension that cannot be seen once assembled. It sets the upper end of the grip, and it is the first thing to check when a pair that worked on one belt fails on a thicker one.
The head thickness is often left off a leather drawing and should be on it. A head that is too thin dishes over a large diameter and marks the leather; one that is thick enough holds its face and keeps the surface flat.
Four properties decide this part, and each carries a cost:
| Property | What it gives | What it costs |
|---|---|---|
| Two-piece post | A joint that opens without cutting | Two parts to stock and lose |
| Flat heads | Bearing area on soft material | Visible on both faces |
| Titanium body | No rust and no staining | Material cost above plated steel |
| Plain finish | Nothing to wear onto the leather | Soft surface marks easily |
The value is a belt, strap or bag that can be opened, shortened or repaired without destroying the leather, in a metal that will not leave a rust ring on the inside face after a wet winter.
The cost is that the material moves under the fitting, so a pair that is right when it is made is not necessarily right a month later, and the design has to allow for settlement in the length rather than hope it does not happen.
The recorded finish is plain titanium. There is no plating to wear off into the leather, and no zinc or nickel that can react with the tannins in a damp strap; the natural oxide is stable and inert in contact with the material.
| Option | How it protects | Effect on the leather | Typical use |
|---|---|---|---|
| Plain titanium | Natural oxide | Inert; no staining | Belts and straps worn daily |
| Anodised titanium | Grown oxide, coloured | Inert; colour on the head | Coloured straps |
| Nickel plated steel | Hard barrier layer | Can mark if it corrodes | Cost-driven belts |
| Brass | No coating needed | Ages with the leather | Classic leatherwork |
| Stainless steel | Natural oxide | Inert; heavier | Bags and heavier straps |
Titanium is chosen where the belt is worn against skin and washed once in a while, and where a rust mark would be obvious on the inside face. Brass is the traditional alternative and ages with the leather rather than against it.
A plated steel pair is the cheap option and works indoors, but a scratch through the plating on the inner head will rust against damp leather, and the stain does not come out.
Three leather products where a removable joint is the point:
| Where it sits | The pair joins a belt end or a buckle loop that has to be changed without cutting the strap. |
| When it goes wrong | The joint loosens as the leather settles, or the heads dimple the surface. |
| Why it happens | The grip was set from the new leather rather than the compressed thickness. |
| What we control | Grip range set on compressed samples; first article worn through a settling test. |
| Where it sits | The pair fixes a strap loop that sees load and movement every day. |
| When it goes wrong | The post rotates in the hole and the joint works loose. |
| Why it happens | The hole is oversized or ragged, and the head is small for the leather. |
| What we control | Hole size and head diameter agreed; sample punched the way the line punches. |
| Where it sits | The pair closes a strap where the fitting is visible and the material is thin. |
| When it goes wrong | The head stands proud, or the leather tears at the hole. |
| Why it happens | The head is thick for the strap, and the hole is close to the edge. |
| What we control | Head thickness and edge distance set from the strap; sample assembled. |
Four points that decide whether a pair still holds after the leather has settled:
|
Grip given as a range
The drawing gives the compressed thickness and a margin, because the material moves after the fitting is made. Basis: Settlement allowed for. |
Both halves made as a pair
The post and the barrel are threaded together, so the pair that runs in the sample runs in the batch. Basis: Pair proved together. |
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Fitted on real leather
The first article is fitted through the customer leather, punched the way the line punches it. Basis: Joint proved on the material. |
Same head, same thread
Head diameter, barrel depth and thread are recorded with the drawing revision, so a repeat lot feels the same. Basis: Same fit across lots. |
A two-piece post on leather is judged in the hand: it should draw up smoothly, stop on the material without dimpling it, and still hold after a month. These four points are what makes that repeatable.
The post and the barrel are turned in titanium: the head is formed and slotted, the post threaded, the barrel drilled and threaded to the depth on the drawing, and both halves finished plain. The first piece of every run is measured on head, slot, thread and depth, and assembled through a leather sample.
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The barrel is the slower of the two parts. Its internal thread has to be cut to a defined depth, and that depth is what sets how thick a strap the pair can take; a barrel drilled a little shallow turns a pair that worked on 3 mm leather into one that will not close on 4 mm.
Titanium work-hardens at the cut, so the slot and the thread are finished with light passes. A torn thread crest on the post will gall in the barrel, and on a part that is opened occasionally that is the difference between a serviceable belt and one that has to be cut off.
The plain finish is the finished surface, so handling marks show. The parts are finished with a light cut and packed so the heads do not rub against each other, because a scratched head cannot be polished back without changing its thickness.
What decides whether a batch of chicago screws passes is the heads that bear, the thread that runs and the barrel depth that sets the grip. The inspection agreement covers all three.
Heads and slot on the projector |
Post and barrel gauged |
Material checked |
Salt-spray testing where required |
The post and the barrel are gauged as a pair, not separately. A post that passes its gauge and a barrel that passes its own can still bind when they are run together, and on a part that is turned by hand that bind is felt immediately.
The barrel depth is measured with a depth gauge and confirmed by assembling the pair over spacers at the two ends of the grip range. That assembly test is the one that matches how the part is used.
The heads are measured for diameter and thickness and checked for flatness. A head that is not flat bears on the leather at one edge, and that edge is where the dimple appears after a few weeks of wear.
Every batch of chicago screws is traceable to the bar it was made from, with the post and the barrel recorded as a matched pair. The material certificate states the grade, the heat number, the chemistry and the mechanical properties, and the inspection record carries the heads, threads and barrel depth.
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 both halves. The records carry the batch number, so a repeat order can be compared with the first on the number that decides the joint: the barrel depth against the compressed leather thickness.
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 leather joint the first article is fitted through the customer’s own leather, because the compressed thickness is a property of the material as much as of the screw. Buyers visit during the process to review samples.
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8,678+
customers served
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87%
of orders from repeat customers
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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 |
Leather compresses under the heads. The pair should be sized for the compressed thickness, not the new thickness.
Only within its grip range. A pair sized for a 3 mm strap will not close on a 5 mm one.
The head is small for the material, or it is not flat on its bearing face.
A punched hole grips the post around its circumference; a drilled hole can be oversized and let the post rotate.
No. Plain titanium is inert in contact with leather, unlike a plated steel part that can rust at a scratch.
Post and barrel lengths, thread, head diameter and thickness, slot, and the compressed grip range.
How a leather chicago screw project runs from drawing to repeat delivery:
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1
Send the drawing and a leather sample
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→ |
2
Grip range and head size agreed
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→ |
3
First article fitted and worn
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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 used for the first article is what repeat orders are checked against.
For a quotation, send the drawing with the post and barrel lengths, thread, head diameter and thickness, slot width, and the compressed leather thickness you need it to hold.
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Post
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Barrel
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Thread
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Heads
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Grip
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Finish
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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
