Lifting manhole cover

[tonkski]

Whenever our cesspit has needed emptying, the cast iron manhole cover has been lifted by levering a screwdriver underneath it. This method eventually went wrong last time and the cover ended up falling into the cesspit. Not a good day. Looking at the cover, it isn’t obvious to me what the correct method is. Would there have originally have been insertion points for a lifting tool, or perhaps bars over the recesses which have long since rusted away? Looking on eBay there are similar covers in a similar state. I’ve posted a couple of photos of mine:

Getting a replacement cover in a better state and of exactly the correct size looks difficult. Could I get bars welded over the recesses? Any other clever ideas or advice please?

[Tim+]

There would have been bars over the recesses as you surmise. Welding cast iron is very difficult I believe but I’ve seen folk brazing stuff to cast iron so maybe that would be a possibility?

Tim

[Brian]

Yes, there is a bar missing.

[tonkski]

Thanks. I read up on welding / brazing and I don't want to run the risk of cracking the cover, so maybe I'll persist on eBay to find one which is in better condition or can be brazed. Might be no bad thing to have a spare.

[SteveW]

Weld a bar to two pieces of screwed rod, drill through the cover and bolt on?

[Tim Lamb]

Or purchase a replacement? 80ukp for cast or 40 or so for pressed steel. Wickes do a lifting handle for 5ukp..

Yes I do know this is uk d.i.y:-)

[Jeff Layman]

To avoid damaging the cover by welding or drilling, what about using a strong magnet to lift it? Something like this:

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The main problem would be getting the magnet(s) off when you've put the cover back!

[SteveW]

The OP did say "Getting a replacement cover in a better state and of exactly the correct size looks difficult".

I know that when the one in my drive cracked, the crew sent out to deal with a sewer blockage tried to get a replacement lid, but failed and it ended up with the whole frame being dug out and the chamber brickwork height reduced, to suit a whole new unit.

[Chris Hogg]

IME the OP will need to replace both the cover and the frame, because it's difficult to find a new or even S/H cover that fits an old frame. The sizes were not standardised.

I found a couple of covers and frames at our local 'recycling centre' in the days when they let you browse the reusable stuff and before it became commercialised, and pay the operators a nominal sum, some twenty years ago now. Only cost a few quid.

The OP described the tank as a cesspit. Does he mean a septic tank? Cesspits need emptying frequently, often every few weeks, while septic tanks need emptying only every few years.

[Algernon Goss-Custard]

tonkski [e-mail]> posted

How did you get it out, JOOI?

[tonkski]

Tank was completely emptied and then someone had to enter it. Gas tests first etc. Fortunately the tank had been emptied and jetted quite recently so wasn’t too sludgy.

[williamwright]

When a cover is replaced it's often necessary to also replace the frame, because the right size can't be found. What I suggest you do is drill two holes in the cover through the bottom of the recesses and thread a length of stout galvanised stranded wire or nylon rope through to make a loop. The wire can lie flat when not in use but will be something to get hold of when you need to lift the cover. That's what I did and it solved the problem.

Bill

[williamwright]

That's what always seems to happen.

Bill

[John Rumm]

The two main issues welding it as I understand are that the high carbon content can make the resultant weld very hard and brittle. Also it is prone to cracking if heated or cooled too rapidly.

Hardening is a particular problem if you need to machine what you have welded after. In this case that is unlikely to be a problem.

Preventing cracking can be helped by preheating it with a big blowtorch first. Stick welding with as low an amperage as you can get away with, and then wrapping it up in a fire blanket (or burying in sand) to slow the rate of cooling. You can get high nickel content rods for welding cast iron.

You could take the approach: "have a go, if it does not work, then replace the whole thing (including frame probably)"

Drilling and bolting on handles would also work.

[Bob Eager]

And if you have to replace it, use a circular one. You can't drop the lid down it!

[RJH]

Could you not just bolt some sort of handle arrangement to solid parts of the cover, at least as a short term solution? Assuming it comes off in something approaching reusable condition of course . . .

I tend to pack the edges with grease on the rare occasions I've needed to lift the sewer cover.

[fred]

You could try a piece of chequer plate cut to size and reinforced if necessary with handle welded on

[tonkski]

Thanks for all the suggestions everyone. A few points worth mentioning: we walk over the manhole, so I’d rather avoid creating a trip hazard with big handles. It covers a cesspit (not a septic tank) so I need to avoid too much rainwater entering the tank and filling it up, so holes in the manhole might be problematic. The tank is a semi-buried brick thing with a pebbly concrete top, and it looks tricky to replace the existing cover and frame. The cover has only been dropped once in about twenty years so I can probably afford to wait and see if a replacement cover turns up on eBay. The proper long term solution is probably to bite the bullet and get a fancy modern septic tank installed, but I just can’t face the hassle and expense at the moment.

[John Rumm]

If you look at the underside of it, can you see those hemispherical depressions where the handles used to be?

If so, could you drill holes in them such that you could pass a bolt through them? In effect creating a new "handle" that is set down into the depression a little bit.

Alternatively, bolt a short sections of chain to the bases of the handle depressions. When not in use it could lay in the recess.