What size is this Screw?

fishkeeprian · 04/24/2019, 04:04 PM

Hello, the bottom leveling screw broke off my Two little fishes 150 phosban reactor. I contacted them and sent me the attached drawing. I ordered some M3 nylon screws but they are to small. What does M3/16 mean, I'm from the UK so I may have misunderstood this drawing.

Screenshot_20190424-225844_Gallery.jpg

Vinny Kreyling · 04/24/2019, 04:40 PM

Screw is 3 mm diameter 16 is the thread.
in the US it would be threads per inch, in the UK ?
A good hardware store should be able to match the drawing.

mcgyvr · 04/25/2019, 04:59 AM

Quote:

Originally Posted by fishkeeprian

I ordered some M3 nylon screws but they are to small. What does M3/16 mean, I'm from the UK so I may have misunderstood this drawing.

It means nothing.. Its not a correct thread size designation in either the US(SAE/ANSI) or Metric standard.

A "typical" M3 screw has a .5mm pitch

In the US we specify threads per inch but for metric you specific a thread pitch (spacing between threads)
One would not specify a thread as M3 with 16 threads per inch..

Are you not able to just take the broken piece or reactor to a hardware store and match up the threads with a nut or screw there?
Thats what I always do when I don't know the exact size/designation..

04/24/2019, 04:04 PM	#1
fishkeeprian Registered Member Join Date: Feb 2016 Location: England, Earl Shilton Posts: 1,452	What size is this Screw? Hello, the bottom leveling screw broke off my Two little fishes 150 phosban reactor. I contacted them and sent me the attached drawing. I ordered some M3 nylon screws but they are to small. What does M3/16 mean, I'm from the UK so I may have misunderstood this drawing. Screenshot_20190424-225844_Gallery.jpg __________________ If in doubt ask!

04/24/2019, 04:40 PM	#2
Vinny Kreyling Registered Member Join Date: Nov 2002 Location: Miller Place, NY Posts: 7,206	Screw is 3 mm diameter 16 is the thread. in the US it would be threads per inch, in the UK ? A good hardware store should be able to match the drawing. __________________ 250 gallon mixed reef, 2 Reefbreeder's Photon V 2, Deepwater BLDC 12, DAS EX-3 Skimmer, MTC mini cal, 2-3/4" Sea Swirls, Aquacontroller & 6 Tunze pumps.