ZUFEK
Compare the four contact mechanisms
| Point form | Contact | When to review it | What to verify |
|---|---|---|---|
| Flat point | A broad end face bears against a prepared flat or pad. | Review for adjustments where a sharp biting edge is undesirable. | It can still mark the mating surface. Check flat alignment, contact pressure and retention. |
| Cone point | A pointed end engages a suitable recess or indents the mating surface. | Review for a defined setting where penetration or a mating recess is acceptable. | Repeated relocation can damage the contact area. Define the cone and the mating feature. |
| Dog point | A cylindrical extension enters a prepared hole or slot. | Review when the extension must locate or guide a component. | Specify projection, diameter, clearance and available depth; do not let the point bottom unintentionally. |
| Cup point | The rim of a recessed end makes concentrated contact. | Review for a setting where an indentation is acceptable. | Do not assume an undamaged surface after removal, or infer a universal holding force from the point name. |
Compare the contact mechanism first; confirm capacity and installation on the actual joint.
Download the point-selection worksheet (English)Make the adjustment trial repeatable
Worked review only. Inputs and acceptance criteria belong to the actual drawing; no customer test result or universal performance rating is claimed.
- Before the trial
- Point and pad drawings, permitted marking, adjustment travel and the agreed retained-setting criterion.
- After the service sequence
- Starting and returned positions, contact condition and outcome against each criterion; identify the point, pad and drawing revisions.
Choose the contact mechanism first
A point name describes geometry, not the holding capacity of the completed joint. Use the comparison below to shortlist a contact mechanism. Then provide the mating material and hardness, the prepared flat, recess or hole, and the intended adjustment and release procedure. A flat point is worth reviewing when a sharp biting edge is undesirable; it does not guarantee a mark-free shaft. A cone or cup can indent the mating surface. A dog point needs a defined mating hole or slot.
Work through an adjustable-stop example
Consider a fixture stop that is reset between jobs and contacts a finished pad. This is a design exercise, not a delivered customer case. First decide whether indentation is acceptable. If it is not, review broad-face contact and the pad material before selecting a point. Check alignment throughout the adjustment travel: a nominally flat end can contact on an edge if the screw approaches at an angle.
Separate location from frictional clamping
If a cylindrical dog enters a hole, show its projection and the available hole depth. Decide whether that extension locates the part, guides its movement or transmits a defined load. Provide clearance for the intended motion and check the installation sequence. Do not assume that an extension in a hole is an approved shear connection or that tightening the screw establishes the required retention by itself.
Release a point and a verification plan
Show the thread, drive access, overall length, point dimensions, final material condition and surface treatment on the controlled drawing. Agree installation requirements and a functional trial on a representative mating component. Record permitted marking and the behavior after the required adjustment or service sequence. No general torque or holding-force value is supplied here: those depend on the actual joint.
Write a repeat-adjustment acceptance record
For the fixture-stop exercise, define the starting setting, allowed contact mark and adjustment/service sequence before the trial. Check contact at both ends of travel and after returning to the starting setting. Record whether each result is a visual assessment, a dimensional reading or a functional observation. If the pad or point geometry changes, compare against the same criteria rather than reusing the old result. This creates an acceptance record; it does not establish a universal tightening torque or holding force.
Specification example
Illustrative review outcome: a repeat-adjusted stop uses a prepared contact pad and a defined end face. The trial checks contact throughout travel, visible marking and retention of the setting under the agreed conditions. Dimensions, material, torque and loads remain project inputs; no test result is claimed.
RFQ checklist
- Point form and controlled geometry
- Mating surface, recess or hole drawing
- Allowed marking and adjustment sequence
- Thread engagement, access and installation requirements
- Dimensional and functional acceptance criteria
Use the RFQ preparation checklist, then submit your drawing for review. For acceptance requirements, see quality planning.
General guidance only. Material properties, tolerances, standards and manufacturing feasibility must be verified for the actual specification. This article does not establish a product performance guarantee.