Resurrection of a CFEI 100 KVA Induction Furnace

[awemawson]

Well so much for complacency - very minor snow fall last night, quite a bit of rain, and a major leak into the foundry 

The workshop side leak that I 'think' is water getting between the barge boards is no more than I'd expect BUT it looks like at least a gallon or so - probably more - has got in on the west side of the roller shutter, and run the entire length of the foundry underneath all the machines. The leak must be on the roller door end of the foundry and has run down the edge due to the tilt of the floor, but whether it has come under / round the door or through the roof is not clear.

I'm at my wits end trying to get this building sufficiently waterproof to actually use 

[awemawson]

Looking at the internals of the roof over where the main ingress was I can find no damp patches so my preliminary conclusion is the water has come round or under the roller shutter, and when I have someone to assist outside with a hose I may be able to track it down.

However we obviously had much more rain last night than I thought as doing my rounds I find that our fields are flooded. Speaking to a friend who keeps a rain gauge apparently yesterday afternoon and night we had over two inches of rain.

. . . hey ho . . . mutter mutter mutter 

[awemawson]

So the rain stopped for ten minutes so I've applied squirty foam between the cement fibre and wooden barge boards on the main workshop. Note this is not intended as a seal in itself, but when trimmed back with a knife when set will allow the Cromapol roof gunge to bridge the gaps that otherwise are too big.

Bit of dribble clean up required down the cladding boards !

[awemawson]

Squirty foam expanded and set nicely despite the lowish temperature (4 deg C) so I managed to trim it back and slosh on the Cromapol fibre reinforced sealant, so fingers crossed it may have solved the leak on the main workshop side of the foundry.

Still trying to puzzle out the bigger leak on the west side 

[mattinker]

H Andrew,

Very crossed fingers! I won't be coming over for Christmas but maybe I'll get to see it later in the year!

Cheers, Matthew

[awemawson]

That's a shame Matthew but I fully understand.

Having managed to dry up the major flood (brushes, mops, then a powerful blower) I was able to carefully ply a hose on the threshold strip and totally proved that nothing was getting under it or round it. I then propped the hose up the channel that the shutter runs in and left it for a while so the water ran down the vertical channel as would rain hitting the shutter. Not a drop came in 

Still need to test if rain is blowing over the threshold strip where the shutter D seal doesn't press as hard due to the sloping floor,  but that's a two man job. Might be able to persuade the other half to help this afternoon.

[awemawson]

So the good news is that I've not had water come in the Foundry now for several days. I've been busy slapping Cromapol on various joints, mainly the main vertical outside corner between the foundry and main workshop, which I'm sure has been a problem at times. Where the foundry abuts the original building where it is  'feather edge' wooden cladding, the gaps had been left as raw expanding foam which I have trimmed back with a knife and Cromapol coated. It doesn't look very pretty but it's certainly more water proof!

However it must be said that we haven't really had much rain - what we have had has mostly been over night - so I see wet paths in the morning but no real idea of quantities. Often what is forecast bears little relationship to what actually falls so I decided to rig up a 'rain gauge' . At it's crudest just a tin can, but then you have the pain of remembering to empty it out so I researched commercial devices and found a self emptying radio link jobby for only about £30 so not worth re-inventing the wheel!

It's a clever design that gathers the rain in a funnel and funnels it to a tipping rocker that when enough water is gathered tips over so the other bucket gets the water and transmits a signal to the receiver - all automatic, no emptying, and it accumulates data by hour, day, month and year.

Last night was the first 'active' night with rain - 2.5 mm - not a lot but still no leaks 

. . . time will tell

[vtsteam]

Cool device Andrew. 

I feel funny wishing you this but I hope it rains hard where you are in the next few days, so you can feel confident enough to get the foundry going.

We, on the other hand just got an unwanted and insufficiently predicted  Noreaster day before yesterday that put down 60cm of snow with high winds. Negative 17 C out this morning. Miserable! To add to the problems my plow tractor had it's front wheels off waiting for new rims and tires a few days before the storm hit which were then delayed. Shoveled  third of a mile to the cars through this arctic mess to pick them up. Just getting them back on the tractor this morning.

Anyway, I wish you rain (only if you want it) !

[awemawson]

Oops Steve yes that sounds pretty bitter 

Odd isn't it, wishing for rain but yes that's the situation !

Now tell me about earth worms - tentatively moving one of the clothing lockers in the foundry that are waiting for that corner to be 'cured' of leaks I found a nice big juicy earth worm under it's base - locker at least 12 foot into the foundry from the outside world. Raising the roller shutter to throw it out, there was another equally juicy fat one under the shutter seal waiting for a chance to dash in (do worms dash?).

I have cameras pointing at the potential leak areas and first thing this morning doing my 'in bed by iPad' inspection there appeared to be a long thin trail of water from the base of the shutter inwards. When I got out to it an hour later I found it actually was ANOTHER worm trail but by this time it had dried out and there was a dead worm at the end of it

. . . what is it with these worms . . . what's so attractive about my foundry 

[vtsteam]

Well I'm no expert but they respond to negative stimuli generally by going above ground. Vibration for one -- their mortal enemies, moles, make characteristic vibrations when digging, and the escape route is up and out of the ground for that. Subsoil life is kind of like undersea warfare with sonar signatures. Anyway, they can get fooled by equipment vibration. They also respond to stray electrical currents and will go above ground for that. Excess water will drive them above ground. And finally chemical irritation. So, any of that going on by your workshop: vibration, stray electrical currents, chemical compounds and solvents, or excess water?

Or moles?

[awemawson]

All of the above   

[vtsteam]

Richard Gene the Fishing Machine, one of my fishing heroes! 

[awemawson]

He's a bit over the top on the enthusiasm scale for a Brit  to appreciate 

So forecast was for very little rain over night, but actually it was pelting down at times and rattling the windows, so with a bit of trepidation I went out to inspect this morning. We had actually had 11.9 mm (or nearly half an inch) but yes there was a bit that had come in but dramatically less than on previous 'pre-sealing' days.

I rather suspect that some at least of what has entered has come under the bottom row of blocks of the wall - there is no DPC and anyway the interior slab extends beyond the wall outside at the same level. I need to flaunch a fillet where the wall meets the slab to cast the water away from the wall.

But look carefully and you'll see yet another worm visitor on this damp patch !

[awemawson]

Well definitely progress here 

Another 24 hours with about half an inch of rain, but no under wall penetration in the corner where that last worm was. Why - well I put a generous fillet of sand and cement down yesterday where the wall meets the slab on the outside and it has worked 

The side wall of the foundry is also letting water underneath which is puddling behind and under the induction furnace driver box, and when I look outside it's no wonder. The ground falls towards the wall and there is a bally great accumulation on the outside where it's coming through.

I started yesterday digging by hand to fully expose the slab and dig a trench beside it so that I could hopefully get the water to flow away from the wall, and again add a generous fillet to the base. After about six foot of digging  that rapidly got unattractive. So this morning I managed to change buckets on the JCB803 ready for tomorrow when hopefully we have a brief dry spell.

But, looking on the bright side, water isn't now coming through the roof (I hope) and the problem is down at ground level.

Another major bonus is that the Water Board next door have now felled and removed the massive willow that was dumping leaves on the foundry roof. They promised to do this earlier in the year, and it had been over looked, so when they turned up to cut the grass last week I descended on them in my best persuasive manner resulting in the four man team with chain saws and a chipper reducing it to history over the next two days.

[vtsteam]

Eight man days......I think that was a sequoia.

[Muzzerboy]

Ah, so the edge of the slab was under the soil (and the transient water table by the looks of it). With no DPC, that seems to explain the remaining ingress. Certainly, keeping the slab clear by means of a drainage trench sounds like a plan. Beers all around! 

[awemawson]

Eight man days......I think that was a sequoia.

No just Water Board employees !

Actually in fairness the main offending willow was surrounded by many smaller bits of scrub and smaller willows - all self seeded. Willow grows like a weed round here. Every year I get a neat little row of very short willow saplings growing in the gutters - easy to remove as they come out as a strip ready for planting - just pull one end and the rest follow !

[awemawson]

Ah, so the edge of the slab was under the soil (and the transient water table by the looks of it). With no DPC, that seems to explain the remaining ingress. Certainly, keeping the slab clear by means of a drainage trench sounds like a plan. Beers all around! 

Long term I'd like to put a perforated land drain in a trench by the slab covered in pea shingle - not sure of levels - I need to get the laser level out and see where I have sufficient fall to get it to clear.

[awemawson]

Major setback this morning. 

The entire foundry floor is covered in water - not puddles but like very heavy condensation. Now a bit has probably come under that side wall as it did the other day but I suspect that it's actually coming up through the concrete slab. I'll see if I can find any pictures of laying it, but I don't think that there is a membrane in it as it was originally intended as a yard.

I know that there is a rubble filled soakaway under it that I put in to take water from a surface water 'Acco' drain channel that was originally outside the sliding door to the welding shop, but has ended up in the foundry (so takes no water).



So what to do? I'll carry on and scrape the earth away from the side wall as I previously mentioned (but its too soggy today) but as for the floor the only two solutions that I can come up with are:

A/ Break up the slab and re-lay it with a membrane (difficult as the walls rest on it)
or
B/ Lay a thick screed onto the existing slab but on a membrane (not ideal as no bond between them and there will be screed thickness steps at doorways of 50-75 mm)

(or C/ Give up and take up stamp collecting !)

argh . . argh . . . argh . . . argh


Later Edit:

Searching my photograph archive the jury is still out.  Two relevant  pictures, one showing the Acco drain pre-concrete and another that has some unlaid membrane in the vicinity but not laid so I'll have to excavate the side of the slab to be sure either way

[mattinker]

Andrew,

What a pain!

Cheers, Matthew

[awemawson]

Yes Matthew I'm utterly fed up with the whole business 

Very difficult to take decent pictures of the issue but these give you an idea of the extent of the wetness.

This equipment should have been in use MONTHS ago - everything works but I daren't use it in full flow pouring metal when things are as damp as they are.

I do occasionally run up the generator and switch on the induction furnace driver and get something glowing to try and keep the internals from getting too damp but that's a different ball game from pouring metal.

[Pete.]

I'm afraid that I would be forced to just 'put up with' that given that the damp is in the slab not on it. The benefits don't out-weigh the effort involved IMO. The weather is seldom as wet as it is right now, it might just be that the ground is so sodden that no soakaway is going to work. That's bound to bring the damp up through.

[Muzzerboy]

Well, a land drain trench around the slab might at least lower the water table under the slab. That way at least you wouldn't have water wicking up from below when it rains.

I have reinforcement and DPC under my slab but I have a different issue. The cowboys who laid it either levelled it off too much or did it when it was pissing down. Consequently there was standing water on the surface when it was trying to set, so the surface has no strength and has a cratered surface. Really not what I was planning and made the surface paint laughably pointless. I was in China at the time otherwise I might have twigged WTF they were up to.

Murray

[hermetic]

It could be condensation dripping off the underside of the sheets and then soaking in to the floor, maybe best to go in there when the temperature drops at 3 or 4 in the afternoon, and check for moisture on the underside of the sheets. You would have to cut the concrete at the edge of the walls to put a membrane in, but what a pain! Could you dig (though it is hardly the weather for it) an exploratory tunnel under the concrete to see if there is a membrane. I think that it is very unlikly that the water has come up through the concrete overnight, when it was previously dry, but I do not know your local conditions as to water table height, and also how well the concrete was tamped. Still, I think if it was coming up through the concrete, your yard would be virtually under water! Have a good Christmas, it will soon be time to put all this behind you, fill your glass, and put your feet up! All the best Andrew, hope you get it sorted, as I may have a little commision for you!
Phil

[vtsteam]

Portland cement neat is waterproof. I have a 3000 gallon above ground cistern that does not leak weep, or get damp. the inside and outside are painted with a heavy coat of pure Portland mixed with a small amount of sharp sand to increase coating thickness and give tooth to any needed subsequent coats.

If it was me, I'd paint the floor with a heavy coat of pure Portland and a little sand, then while wet, put down reinforcing steel mesh and add another 4" of very rich concrete over. I'd skip membranes, as yes, you'll get no bond at all , and it's just wasted plastic  technology BS. You'll just have a layer of water between. Raising the floor 4" will help with drainage, too.

4" minimum over and yes, reinforcing, so nothing moves or cracks ever again. When semi cured, I'd hit the top surface with one more coat of Portland and sand. This whole will be waterproof.

Drainage won't stop a permeable pad with water under. You want impermeable, and made out of like materials. Forget plastic miracles. Sure, improve drainage, but a spongy concrete slab is just that, a sponge.