Mill Bolt Source?

I was tramming in my Twin Mill\Drill and i overtightened the cam lock head bolt and broke it.

Where would be a good place to get one? Its 110mm 1/4 BSW 20G with about 50mm of threads.

Can anyone suggest somewhere? I assume it needs to be hardened bolt?

Many thanks.

James

Looks a bit of a one-off with a head that size.
Could you get by with a ¼" UNC bolt? if so Spalding fasteners sell them
https://www.spaldingfasteners.co.uk/1-4-unc-grade-8-10-9-hex-head-part-threaded-bolts-yellow-zinc-plated/

Is the hex head on yours 7/16" 0.438" UNC or 0.445" BSW?

Bill

I'd think it tough rather than hardened - you want accidents to break that, not the more critical parts.

Hi Guys

Thanks. The head doesnt matter at all. Any old hex head will do. So yes, i can almost certainly use the spalding one.

Many thanks

James

If one did make one's own, what would you use? EN4, EN24?

I would use EN8 as have some in stock that would suit, also EN16T but don't think it necessary.

Emgee

EN16T is the stuff to use but If I made it, it'd come with a 3/4" AF head, because that's what I've got..

Edited By Mark Rand on 06/06/2022 19:14:19

FWIW, Make one!

No need for a forging.

The drawbar on my milll has a hexagon head pinned to the 3/8 BSW drawbar proper and had survived my use for over 20 years.

Howaqrd

the draw bar on my mill is a piece of threaded bar from the local tool shop with a nut brazed on the end