8-32 screw oddball

[little ol' e]

Everything that I searched on the WW interweb says #6, #8, #10 32 TPI for N-Am electrical.
I can see how old fixtures violated by a previous handy-man (or handy-woman) may not fit properly. So the only logical conclusion seems to be loosey-goosey quality control because I know some brand new fixtures from Big Box Hardware did not fit my fasteners. I figured maybe we went metric there too when I was delirious with Covid.

406.5 Receptacle Mounting.

The machine screws that come with the receptacle should be used.

www.electricallicenserenewal.com

The material used now is Dual Phase. Not to say you couldn't strip the threads like the older boxes, but, the strength of Dual Phase material is much better. No more loosey-goosey threads.

Peter,
Covid did some crazy things, but rest assured, you didn't get delirious over a metric changeover with electrical boxes lol.
Most older generation boxes/plates had the threads stripped during apprentice's installation from what I heard back when. Probably why the screws that Susquach had on hand wouldn't work.

Their are other plates, boxes that have 1/4-20 , 10-32 and 8-32... using same DP steel. I could post some pics once I do another run of the others to show differences. If anyone is interested.

Eric

 

[Janger]

The material used now is Dual Phase. Not to say you couldn't strip the threads like the older boxes, but, the strength of Dual Phase material is much better. No more loosey-goosey threads.

Peter,
Covid did some crazy things, but rest assured, you didn't get delirious over a metric changeover with electrical boxes lol.
Most older generation boxes/plates had the threads stripped during apprentice's installation from what I heard back when. Probably why the screws that Susquach had on hand wouldn't work.

Their are other plates, boxes that have 1/4-20 , 10-32 and 8-32... using same DP steel. I could post some pics once I do another run of the others to show differences. If anyone is interested.

Eric

Eric what is dual phase steel? And please post pictures of making those parts if you are allowed to. We’d love it!

 

[Susquatch]

The material used now is Dual Phase. Not to say you couldn't strip the threads like the older boxes, but, the strength of Dual Phase material is much better. No more loosey-goosey threads.

Peter,
Covid did some crazy things, but rest assured, you didn't get delirious over a metric changeover with electrical boxes lol.
Most older generation boxes/plates had the threads stripped during apprentice's installation from what I heard back when. Probably why the screws that Susquach had on hand wouldn't work.

Their are other plates, boxes that have 1/4-20 , 10-32 and 8-32... using same DP steel. I could post some pics once I do another run of the others to show differences. If anyone is interested.

Eric

Are you talking electrical boxes here or lighting? I suspect that all that subsized 8-32 stuff is peculiar to lighting fixtures downstream of the electrical box - ie lamp corded. But maybe it is worth checking on that too.

 

[Susquatch]

Most older generation boxes/plates had the threads stripped during apprentice's installation from what I heard back when. Probably why the screws that Susquach had on hand wouldn't work.

Just to clear up a little confusion, none of the screws are damaged in anyway.

The originals all fit perfectly and are interchangeable. Brand new screws from a lighting outfit also fit perfectly.

But brand new 8-32 Screws do not fit and will not even start. They are simply too big in diameter.

See my earlier chart of sizes. Both screws are clearly 8-32, but the lighting screws are very slightly smaller - sufficient to make them non-interchangeable with regular 8-32s. They will however fit an 8-32 nut - albeit loosely.

Personally, I think @Dabbler has generated the most likely explanation for what has happened here. I do not think this is caused by abuse or heavy-handedness. I believe it is a simple case where one small sector of the electrical business in North America (the lighting folks) has drifted away from the accepted standards that everyone else uses.

 

[little ol' e]

Eric what is dual phase steel? And please post pictures of making those parts if you are allowed to. We’d love it!

Hey John, Off the top of my head I don't recall the percentages of materials used. One being Ferrite, that just stuck in my mind for some reason.
I would have to look at my notes attached to the files. The tensile strength ranges from about 450MPa to about 1200. Tuff stuff really.
After laser, they go into fixtures for machine tapping.

We began switching over to that material around 2018 IIRC for all lighting housings, which in turn changed the process on how they were made from the old way of stamping dies.
Although I'm not 100% sure, Big box stores and other chains may still sell the older galvanized styles. If so, as far as I know they are not being used in new construction.
Once we do another run in November, I will post more pics. Just can't share the prints or files.

 

[little ol' e]

Are you talking electrical boxes here or lighting? I suspect that all that subsized 8-32 stuff is peculiar to lighting fixtures downstream of the electrical box - ie lamp corded. But maybe it is worth checking on that too.

We do many of both, The pic I posted above is 1 part of a lighting style box. We don't make any of the standard 110 or 220 wall boxes in house currently. Difficult to get young guys loading-unloading a piercing-forming machine all day. Getting guys to run a CNC mill doing tapping is much easier.
Not sure on the specs of the NEW 8-32 screws that you bought, sounds like poor quality control or offshore sourcing. To my knowledge the screws are to be standard across the industry.
When you say the 8-32 will not even start due to the diameter being to big, I suspect it would be 6-32 but others may have been it that box before you by the sounds of things. ( oh... Shiver my timber by the sounds of that eh )
Glad you got it sorted out thou. Take a pic of what you done just so we can see what you were working with if you gat a chance.

Oh, I used Nitrile gloves to cover up my hairy knuckles just for the picture haha.