Snap-in post
- Fast assembly without tools
- Barb flex fatigue if the board is removed often
- Hole size tolerance drives retention
Molded part guide: standoffs
Injection Molded Standoffs
Standoffs set the gap between a PCB and a cover or chassis. They can snap into the board, snap into the shell, or receive a screw from below. If the posts are not the same height after molding, the board rocks and connectors misalign.
PCB mount
Parallel posts matter more than post diameter
Molded standoffs are often integrated into an enclosure bottom or a separate pillar plate. Each post must match the PCB hole pattern and hold the board at a fixed height for connectors, displays, or battery clearance.
Snap standoffs use a flexible barb that passes through a board hole and locks. Screw standoffs use a boss with a metal insert or self-tapping thread . Mixed patterns on one board need a clear assembly sequence.
Warp on the mounting plate telegraphs into standoff height variation. Stiffen the plate with webs, balance fill symmetrically, and define which face is datum for the board.
Service tiers
Standoff service tiers and quote path
Standoffs set PCB or panel stack height. Pick the tier that matches retention method and torque, then quote with hole pattern and target stack height in notes.
| Tier | Environment | What matters most | Typical resin route | Quote path |
|---|---|---|---|---|
| 1 Snap standoff | PCB snap-in, low pull force | Hook flex and panel hole range | PA or PC snaps | Instant quote; note board thickness range |
| 2 Screw standoff | Through-board or panel screw | Boss height stack and thread stripping | ABS or PA bosses | Instant quote; material field ABS or Nylon |
| 3 Insulated stack | Keep clearance to metal chassis | Creepage path and boss cracking | PC or unfilled PA | Instant quote; note the clearance to the chassis |
| 4 High torque post | Metal insert or self-tapping zone | Insert pull-out and post ovalization | Glass-filled PA posts | Upload CAD; include insert part number if known |
| 5 Parallelism critical | Multiple posts, tight board fit | Molded-in stress and post splay | Same resin as the shell | Full RFQ; flag critical dims on drawing |
Materials
Resin families: quick reference for quote notes
Standoffs are usually unfilled or lightly filled nylons or PC. Put target stack height and retention type in comments.
| Family | Typical use on this part type | Notes for instant quote |
|---|---|---|
| PA (nylon) | Snap and screw posts | Field Nylon; say if glass filled |
| PC | Insulating posts | Field PC |
| ABS | Indoor screw bosses | Field ABS |
| Glass-filled PA | Higher torque posts | Field glass-filled nylon |
Retention
Snap post or screw-mount standoff
Screw standoff
- Service access with a screwdriver
- Metal insert or self-tap thread at each post
- Torque must not crack thin post walls
Integration
Standoffs molded into the enclosure floor
- Posts should tie to the floor with gussets, not stick up as isolated cones
- Keep weld lines away from barb flex zones
- Define board datum relative to connector cutouts on the shell
- Metal inserts at high-load posts reduce post stress
Avoid these
Common design mistakes on molded standoffs
Two choices that show up as a rocking board or a connector that will not mate.
Letting the mounting plate warp, so the posts are no longer the same height. Webs and a balanced fill stiffen the plate. Name which face is the datum for the board.
Leaving each post as an isolated cone. Tie the posts to the floor with gussets. A post that only sticks up from the floor is where the board rocks.
Drawing
Standoff quote inputs
PCB drawing with hole diameters and pattern
Required board height and keep-out above and below
Snap or screw at each post location
Components that must align to shell features
Service cycles if snaps must release
Whether standoffs are on the shell or a separate plate
Keep reading
Related guides
Electronic enclosures
Board datums in the shell.
Electronic enclosuresSpacers
Tubular distance on bolts.
SpacersSnap fit clips
Barb flex design.
Snap fit clipsBosses
Screw posts.
BossesInsert molding
Threaded inserts in posts.
Insert moldingTolerance stack up
Board height stack.
Tolerance stack upEnclosures
Shell closure context.
EnclosuresWarpage
Plate warp lifts posts unevenly.
WarpageMolded parts library
Every part-type guide.
Molded parts libraryFAQ
Questions about molded standoffs
Can standoffs be a separate plate snapped into the shell?
Yes. Send both parts and the assembly sequence so retention and height stack are reviewed together.
Our connector does not mate after molding.
Measure standoff height and pattern relative to the shell datum. Warp or shrink on the floor often shows up as connector offset before hole pattern error.
Are metal threaded standoffs available molded in?
Insert molding can capture metal standoffs. Send insert drawings and torque requirements.
Do you assemble the PCB?
No. NetProto molds plastic parts. Board installation stays with your assembly line.
When should the post be a screw instead of a snap?
When the board will be removed for service. A snap barb is flexed each time the board comes off. A screw post opens with a screwdriver. The torque still has to stay off a thin post wall.
Why are the molded posts not the same height?
The mounting plate warped, and that warp becomes a height error. Measure the posts from the shell datum. Webs and a balanced fill are what keep the floor from moving.
Next step
Quote standoffs with PCB and shell CAD
Upload enclosure and board data with target height. DFM feedback covers post warp, snaps, and boss torque.