Model engineering oil cup / glass oiler connection thread (alternate size) screw size
M4 · length not stated in the sources
The screws used on Model engineering oil cup / glass oiler connection thread (alternate size) are M4. None of the sources we found gives an exact length, so measure the original before you order.
The record covers 'Oil cup made of brass with M3 or M4 connection thread. For screwing into steam engines, flame eaters and Stirling engines'.
This entry is marked confirmed and comes from bengs-modellbau.de.
M4 means a 4 mm nominal diameter with a 0.7 mm thread pitch. Imperial look-alike: #8-32 (4.17 mm) — the standard US PC/rack screw, close but not the same.
Model engineering oil cup / glass oiler connection thread (alternate size) screw specifications
One row per fitment record. Head, drive are shown only where the source states them; pitch is the ISO coarse pitch for the thread.
| Thread | Length | Pitch | Head | Drive | Where it goes | Status |
|---|---|---|---|---|---|---|
| M4 | not stated | 0.7 mm | not stated | not stated | 'Oil cup made of brass with M3 or M4 connection thread. For screwing into steam engines, flame eaters and Stirling engines' | Confirmed |
Fitment records and sources
'Oil cup made of brass with M3 or M4 connection thread. For screwing into steam engines, flame eaters and Stirling engines'
pitch 0.7 mm · tap 3.3 mm · clearance 4.5 mm · PH2 / Torx T20
How to check the screw before you buy
- Vibration loosens small screws on drones and RC models, so builders commonly add a drop of medium (blue) threadlocker on metal-to-metal joints — never on plastic.
- Diameter: across the threads an M4 screw measures about 4 mm with calipers (usually a hair under). If yours measures noticeably more or less, it is a different thread.
- Pitch: 0.7 mm from one thread crest to the next (14.29 crests per centimetre). A thread pitch gauge or the pitch-gauge tool settles it in seconds.
- Length: measure from under the head to the tip for pan, button, wafer and cap heads; countersunk (flat) heads are measured overall.
- Driver: the source does not name the drive. Standard M4 heads take PH2 for Phillips and T20 for Torx, and a 3 mm hex key for socket heads; a bit that fits loosely will cam out and strip the head.
- Tightening: no device-specific torque is published in these records. The site's general figure for M4 is about 2.0-3.0 N·m into metal threads and 0.8-1.4 N·m into plastic bosses; snug it up and stop.
Common mix-ups with M4
- In EV charging part numbers 'M3'/'M4' often means IEC 61851 charging Mode 3/Mode 4, not a screw thread.
- US-made pinball machines (Williams/Bally/Stern) overwhelmingly use imperial UTS threads (#6-32, #8-32, #10-32); explicit metric threads only appear on newer/import components such as Jersey Jack Pinball's Hobbit Smaug assembly (M3).
More in Drones, RC & Gimbals
The same screw also fits
Devices whose records share a thread with Model engineering oil cup / glass oiler connection thread (alternate size), closest length match first.
- European mortise lock faceplates also M4
- Berkel 330M Slicer base/transmission fastener (short) also M4
- Kolm Engines EZ77V4 model aircraft engine also M4
- Traxxas Spartan SR (Model 103076-4) boat also M4
- DJI Agras Agras T25/T50 spray drone screw with pad also M4
- Model steam engine boiler pipe fittings (elbow/tee) also M4
- Meccano boxed sets (modern metric era) and compatible parts also M4
- GoPro-style action cam mount on FPV frames also M4
Questions about Model engineering oil cup / glass oiler connection thread (alternate size) screws
- What size screw does Model engineering oil cup / glass oiler connection thread (alternate size) use?
- M4 for 'Oil cup made of brass with M3 or M4 connection thread. For screwing into steam engines, flame eaters and Stirling engines'.
- How long are the screws in Model engineering oil cup / glass oiler connection thread (alternate size)?
- None of the sources states a length. Remove one screw and measure it from under the head to the tip (overall for a countersunk head).
- What is the thread pitch of an M4 screw?
- 0.7 mm (coarse), which is the standard pitch for M4 machine screws; a 0.5 mm fine pitch exists but is uncommon. The tap drill is 3.3 mm and the normal clearance hole is 4.5 mm.
- What screwdriver do I need for Model engineering oil cup / glass oiler connection thread (alternate size)?
- The sources do not name the drive. For M4, Phillips heads normally take PH2 and Torx heads T20; socket heads take a 3 mm hex key.
- Can I use an imperial screw instead of M4?
- No. Imperial look-alike: #8-32 (4.17 mm) — the standard US PC/rack screw, close but not the same. Use a true M4 screw so it does not cross-thread or strip the hole.