Big round hole in steel

[Bill]

I need to make or have made 2 additional removable steel supports to match 6 that came with a trailer. The present ones have a smaller steel pipe adjustable inside a 2" outside diameter steel pipe. The larger steel pipe drops in to sockets on the trailer, and has a 1/4" plate welded about 8" up to stop it dropping through the socket and support part of the 2.5 tons to be carried.

My local friendly trailer man can do the welding but isn't happy about making the 2" hole in the 1/4" steel plate.

Is the best tool to cut through the steel a bi-metal hole saw? Should it be 50mm (advertised on ebay as 50mm/2") or 51 mm.

Would it be easier to hack and bodge something like an old Acrow prop? What is the o/d of one of these or are they all different?

Any other ideas? Is this the sort of thing a decent metal fabrication shop should be able to knock up simply and cheaply? The 6 original props are all different, so it looks as though they were cobbled up out of whatever materials were to hand.

[damduck-egg]

With a decently sharp hole saw and a drop of oil as lubrication it should be quite easy and quick if the power tool is reasonably powerful. Used to similar jobs regularly. A note of caution. If the tool is powerful enough to do a reasonable job it will be strong enough to hurt you and break from grip if the saw jams which it often does just as it breaks through unless you are ready. A drill with a clutch is recommended if you have access to one.

G.Harman

[Andy Dingley]

Plasma cutter. A trailer place might not have one, but any halfway decent steel fabricator will.

OD usually, but it's a hard job to get real accuracy out of them anyway.

Acrow props are quite heavy, as they're specced for a serious loading, more than you'd need for a trailer leg.

[The Natural Philosopher]

Isn't a 2" hole in 1/4" steel plate exactly the sort of thing a hypersonic depleted uranium round is supposed to make?

Any friends in the Army?

[PeterC]

It's worth a shot.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Bill saying something like:

Gas axe. Doddle.

[Andy Dingley]

I don't know anyone who still has the requisite skill with cutting this neatly, and who doesn't already have plasma instead of oxy.

[Ron Lowe]

Can't you just drill a series of smaller holes in a circle, gradually enlarge them till they join up and the middle falls out, then tidy up with a file?

[dennis]

A hole saw will do it easily especially in a pillar drill, even a £30 aldi one.

[Bill]

In message , "dennis@home" writes

Well, I've invested 99p on ebay for a hole saw, so we'll see. If I can clear a space to get to the Fobco, I'll give it a go.

I'll also see if some local fabricators I've used before are still there, just in case.

Thanks to all for the advice.

[Jon Fairbairn]

Easier to get the hole in the right place like this:

[Matty F]

I'd just use a 2" twist drill. First I'd drill a pilot hole!