thread size/pitch on Cutler-Hammer panel
Houghton123
| Posted in General Discussion on
I’ve switched over from an old subpanel to a new one made by Cutler-Hammer. The panel has 60 amp breaker, and the holes in the neutral bus are too small for the wire size, so I added a lug to the neutral bus. I used one of the little-headed screws from the bus to attach it temporarily, but would like to use something with a more substantial head for the long run.
The trouble is, the screws in the bus are a strange size. They are definitely larger than No. 10, not as large as 1/4″ – they look like No. 12, but are fine thread. My hardware store doesn’t carry fine thread machine screws in No. 12, and, as far as I can tell from looking up specs tables online, there IS no fine thread in No. 12.
Help?
Replies
It's probably a m6 screw, fine pitch
Take one of the screws up to the hardware store and find a nut that fits it. I would look in the metric aisle too. Square D seems to be 1/4" fine thread.
All panel manufacturers make accessory lugs for that very purpose, the problem is that the box stores fail to carry much in the way of the accessories that are needed to finish a job.
I was wrong - the clamping screws WERE 1/4" - fine thread, to be exact. I hadn't realized how context-specific my perceptions of size were...because they had really tiny heads, they didn't look like 1/4" to me.
Live and learn. A hex-head fine-thread bolt now holds that lug firmly in place.
FWIW if you do run into a #12, a good sharp 1/4-28 tap reams #28 out real quick.