On 23/10/2020 00:05:22, Roger Hayter wrote:
On 22 Oct 2020 at 16:17:18 BST, "JohnP" wrote:

rick wrote in news:rmpqf5$dvk$1
@gioia.aioe.org:

I have a need to find a replacement screw
Luckily thread is nothing esoteric M4 x 8

If a Phillip head .... but the head is fairly wide ~10mm and pretty thin.

Anybody know if there is a name for this type of screw ...

https://flic.kr/p/2jXJRyz


Try "Washer Head Machine Screw"

I'd just add that most common M4 screws have a 0.7mm pitch, and this one looks
to me quite coarse. But 0.5mm (and possibly other pitches) also exist. So
I'd check it, if not with a thread gauge at least with an M4 nut which if
general purpose will probably be 0.7mm.

Could be UNC? #8 has a major of 4.16mm and a pitch of 0.8mm

An M4 thread by default will have a pitch of 0.7mm. If a fine pitch is
specified then 0.5mm is the standard.
https://en.wikipedia.org/wiki/ISO_metric_screw_thread

It's useful to note that if the pitch is not specified then the thread
should be the standard (coarse) pitch, ie:
M4 - will have a 0.7mm pitch
M4 x 0.5 - fine pitch 0.5mm as defined.