What is this sort of screw called? - UK Vintage Radio Repair and Restoration Discussion Forum

Dave Moll · 5th May 2017, 5:09 pm

I would like to obtain some of the screws shown below, but I don't know what they are officially called to enter into a search.

I have nicknamed it a hermaphroditic screw, given that it has a male thread on one end and a female one on the other, but it presumably has a proper name. They are used on chassis-mounted "D" connectors (as used in old-fashioned serial ports) both to fasten the connector to the chassis and to accept a screw to hold in the mating connector.

If anyone can tell me what I need to search for, I would be most grateful.

winston_1 · 5th May 2017, 5:19 pm

Don't know what they are called or where to get them. I have in the past harvested a few from old computer boards, Freeview boxes, and satellite boxes.

kalee20 · 5th May 2017, 5:19 pm

They're usually 4-40 UNC thread for D connectors. Called Jackscrews.

There are long-threaded and short-threaded versions, for whether the connector is spaced off the surface or not.

Biggles · 5th May 2017, 5:22 pm

It might be worth trying a computer repair shop to see if they have some old cases around with them on.
Alan.

Al (astral highway) · 5th May 2017, 5:42 pm

I harvest these all the time, they're great!

TonyDuell · 5th May 2017, 5:42 pm

Maplin do them, order code FP31J for a pair (with nuts and washers). I was going to say that the price seemed very high until I looked at RS here

http://uk.rs-online.com/web/c/connec...r-screws-nuts/

and saw the Maplin price is only about twice the RS price which is NOT excessive I feel.

David G4EBT · 5th May 2017, 5:52 pm

They're called 'Hex Spacer Stand-off Screw-nuts'. (As good a name as any I guess!). A Google search will turn up an infinite range of suppliers and as well as them being available in brass, both plated and unplated, they can be had in nylon, which can be useful if insulation properties are called for.

EG, here are some brass 'uns:

http://www.dx.com/p/diy-m3-4-6mm-hex...-40-pcs-380786

Hope that helps.

G6Tanuki · 5th May 2017, 6:31 pm

They're used in their millions to retain the old-style 9/15/25-pin "D" connectors [RS232/V.24 and VGA video] on the backs of old PCs.

Actually buying these new seems deeply odd: go raid a couple of scrap PCs!

winston_1 · 5th May 2017, 6:50 pm

Quote:

Originally Posted by David G4EBT

They're called 'Hex Spacer Stand-off Screw-nuts'. (As good a name as any I guess!). A Google search will turn up an infinite range of suppliers and as well as them being available in brass, both plated and unplated, they can be had in nylon, which can be useful if insulation properties are called for.

EG, here are some brass 'uns:

http://www.dx.com/p/diy-m3-4-6mm-hex...-40-pcs-380786

Hope that helps.

Those ones are M3 rather than UNC. Maybe does not matter, but no good if you plan to secure a D plug on them.

McMurdo · 5th May 2017, 8:06 pm

http://uk.farnell.com/3m/3341-1l-bul...9mm/dp/2216959

factory · 5th May 2017, 8:10 pm

If the jack-screws are used for "D" connectors found on older PC's they should have a 4-40 UNC female thread, usually the male thread is the same but not always. I had to deal with a Panasonic Toughbook at work that someone had forced an M3 jack-screw to replace a missing one (presumably robbed from another PC) in a UNC thread D connector until they plastic housing inside broke. Repair was quite difficult, but it was mended and a correct jack-screw fitted.

David

Ed_Dinning · 5th May 2017, 8:24 pm

Hi Dave, how many do you need/ any particular length?

Ed

The Philpott · 5th May 2017, 10:09 pm

The (presumably) BA version fitted in the back of some high impedance avominors has a screwdriver slot in the top, but being a typically narrow (and long) slot it is an issue trying to find a screwdriver of a suitable size to avoid chewing the top up. If anyone knew of a source of said screwdriver/s that would be a help.

Records · 5th May 2017, 11:13 pm

Usually those screws are used to hold the plate on the back of expansion cards such as
graphics cards and modems or soundcards.

Diabolical Artificer · 6th May 2017, 6:18 am

I have that all the time Dave, it can take ages putting "self gripping speaker nuts" "self retaining # 5 widgit" and other stuff in the search engine. helps if you know it's called a T nut or a top hat.

The other lads beat me to it.

Andy.

6th May 2017, 3:56 pm

PM sent...

Dave Moll · 6th May 2017, 4:44 pm

Thank you all for the advice and links. As "deeply odd" as it may seem, I have ordered a pack of ten from RS, as for the sake of sick squid it didn't seem worth the trouble of scrabbling around finding old chassis to raid.

5th May 2017, 5:09 pm	#1
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,130	What is this sort of screw called? I would like to obtain some of the screws shown below, but I don't know what they are officially called to enter into a search. I have nicknamed it a hermaphroditic screw, given that it has a male thread on one end and a female one on the other, but it presumably has a proper name. They are used on chassis-mounted "D" connectors (as used in old-fashioned serial ports) both to fasten the connector to the chassis and to accept a screw to hold in the mating connector. If anyone can tell me what I need to search for, I would be most grateful. Attached Thumbnails __________________ Mending is better than Ending (cf Brave New World by Aldous Huxley)

5th May 2017, 5:19 pm	#2
winston_1 Heptode Join Date: Oct 2012 Location: London, UK. Posts: 500	Re: What is this sort of screw called? Don't know what they are called or where to get them. I have in the past harvested a few from old computer boards, Freeview boxes, and satellite boxes.

5th May 2017, 5:19 pm	#3
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,088	Re: What is this sort of screw called? They're usually 4-40 UNC thread for D connectors. Called Jackscrews. There are long-threaded and short-threaded versions, for whether the connector is spaced off the surface or not.

5th May 2017, 5:22 pm	#4
Biggles Rest in Peace Join Date: Feb 2004 Location: Hexham, Northumberland, UK. Posts: 2,234	Re: What is this sort of screw called? It might be worth trying a computer repair shop to see if they have some old cases around with them on. Alan.

5th May 2017, 5:42 pm	#5
Al (astral highway) Dekatron Join Date: Nov 2006 Location: London, UK. Posts: 3,496	Re: What is this sort of screw called? I harvest these all the time, they're great! __________________ Al

5th May 2017, 5:42 pm	#6
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,215	Re: What is this sort of screw called? Maplin do them, order code FP31J for a pair (with nuts and washers). I was going to say that the price seemed very high until I looked at RS here http://uk.rs-online.com/web/c/connec...r-screws-nuts/ and saw the Maplin price is only about twice the RS price which is NOT excessive I feel.

5th May 2017, 5:52 pm	#7
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 5,765	Re: What is this sort of screw called? They're called 'Hex Spacer Stand-off Screw-nuts'. (As good a name as any I guess!). A Google search will turn up an infinite range of suppliers and as well as them being available in brass, both plated and unplated, they can be had in nylon, which can be useful if insulation properties are called for. EG, here are some brass 'uns: http://www.dx.com/p/diy-m3-4-6mm-hex...-40-pcs-380786 Hope that helps. __________________ David. BVWS Member. G-QRP Club member 1339.

5th May 2017, 6:31 pm	#8
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,007	Re: What is this sort of screw called? They're used in their millions to retain the old-style 9/15/25-pin "D" connectors [RS232/V.24 and VGA video] on the backs of old PCs. Actually buying these new seems deeply odd: go raid a couple of scrap PCs!

5th May 2017, 8:06 pm	#10
McMurdo Dekatron Join Date: Jun 2009 Location: Staffordshire Moorlands, UK. Posts: 5,273	Re: What is this sort of screw called? http://uk.farnell.com/3m/3341-1l-bul...9mm/dp/2216959 __________________ Kevin

5th May 2017, 8:10 pm	#11
factory Octode Join Date: Jul 2009 Location: Cheshire, UK. Posts: 1,738	Re: What is this sort of screw called? If the jack-screws are used for "D" connectors found on older PC's they should have a 4-40 UNC female thread, usually the male thread is the same but not always. I had to deal with a Panasonic Toughbook at work that someone had forced an M3 jack-screw to replace a missing one (presumably robbed from another PC) in a UNC thread D connector until they plastic housing inside broke. Repair was quite difficult, but it was mended and a correct jack-screw fitted. David

5th May 2017, 8:24 pm	#12
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,195	Re: What is this sort of screw called? Hi Dave, how many do you need/ any particular length? Ed

5th May 2017, 10:09 pm	#13
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,108	Re: What is this sort of screw called? The (presumably) BA version fitted in the back of some high impedance avominors has a screwdriver slot in the top, but being a typically narrow (and long) slot it is an issue trying to find a screwdriver of a suitable size to avoid chewing the top up. If anyone knew of a source of said screwdriver/s that would be a help.

5th May 2017, 11:13 pm	#14
Records Hexode Join Date: Jul 2011 Location: Harwich, Essex, UK. Posts: 429	Re: What is this sort of screw called? Usually those screws are used to hold the plate on the back of expansion cards such as graphics cards and modems or soundcards.

6th May 2017, 6:18 am	#15
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,667	Re: What is this sort of screw called? I have that all the time Dave, it can take ages putting "self gripping speaker nuts" "self retaining # 5 widgit" and other stuff in the search engine. helps if you know it's called a T nut or a top hat. The other lads beat me to it. Andy. __________________ Curiosity hasn't killed this cat...so far.

6th May 2017, 3:56 pm	#16
Guest Guest Posts: n/a	Re: What is this sort of screw called? PM sent...

6th May 2017, 4:44 pm	#17
Dave Moll Dekatron Join Date: Feb 2005 Location: West Cumbria (CA13), UK Posts: 6,130	Re: What is this sort of screw called? Thank you all for the advice and links. As "deeply odd" as it may seem, I have ordered a pack of ten from RS, as for the sake of sick squid it didn't seem worth the trouble of scrabbling around finding old chassis to raid. __________________ Mending is better than Ending (cf Brave New World by Aldous Huxley)