Removing Millstones

[jehe]

Hi

We're currently renovating a 16th Century millhouse, and need to remove the grinding stones to repair a rapidly deteriorating floor.

Is there anyone on here who has been in the same situation? We'd like them removed but kept whole if possible, however this seems increasingly unlikely.

Any thoughts on the problem appreciated!

[cooperlola]

Some friends of mine just left theirs where it was and redid the floor around it.  It's now the kitchen table (and jolly nice it looks too.)

[jehe]

Sadly they're making the room nearly unusable as the rooms not that big. Also, the beams underneath have been seriously bodged over the years to keep everything standing and many are severely rotted and need replacing - Its rendered both rooms (above and below) dangerous and I'm not keen on doing any work with the weight of the stones still on it!

[pachapapa]

Luke 17.2[:)]

[Gluestick]

Before you act in haste on this, advertise them.

The artisan bread movement realised quite some time ago, one of the problems with modern flours is the way it is milled: crushed between steel rollers which heats it and destroys essential enzymes and vitamins in the process.

Organic flour producers love old French millstones!

See here:

And also try contacting these people.: here:

From an INRA research project a few years back:

The advantages of stone-milling

A recent French study (2002)set out to quantify the differences in the nutritional content of wheat milled between stones and rollers. The researchers took the opportunity to run their tests with samples of three varieties of wheat, each from conventional and organic agriculture. The results are fascinating. The organic wheat, before milling, had larger amounts of calcium, magnesium, zinc and potassium, though there was slightly less iron in the organic samples for reasons that were not explained. Stoneground flour produced higher values than roller-milled flour for both organic and conventional wheats. Milling organic wheat through stones rather than rollers compounded the effects in a remarkable way, so that stoneground organic flour was shown to have 50 per cent more magnesium and 46 per cent more zinc than the roller-milled conventional flour. This effect, it should be emphasised, was observed not in wholemeal but in flours that appear to have been milled to a finer extraction rate of around 80–85 per cent. Magnesium is deficient in many diets, and the role of zinc in good health is well established. It would not be unreasonable to expect the same benefits from organic growing and stone milling to apply to other important micronutrients in flour.

So here we have clear evidence of the nutritional advantages of organic growing and stone milling.

I dread to think how much it would cost to cut new millstones today: compared to the cost of removing, truing and siting existing stones.

There is a group in France, of artisan bakers and millers who have re-cultivated original wheat seeds from museum stocks and are now in commercial cultivation: and need extra stone milling facilities.

 

[jonnymarre]

What excellent advice from the last chap......either way you'll either be losing a roof or a wall to get them out intact.

[jehe]

Thanks for the detailed advice gluestick, however I don't know whether it's worth advertising without knowing if they'll come out without major and expensive effort.

Demolishing part of a roof or wall to get the stones out would be robbing Peter to pay Paul!

I'm thinking there might be a way to lower them into the room underneath. Possibly by lifting them from some of the beams above and somehow moving them sideways (whilst still suspended) across to a hole in the floor.

Whether or not this is possible is another question entirely!!

[pachapapa]

[quote user="pachapapa"]Luke 17.2[:)][/quote]

Dimensions of stones?

Dimensions of milling floor?

Height of floor to ground level?

Either a jury rig with blocks or a crib and jacks for lowering to ground level.

The poutres used to renew floor support might well be used first to assist in rigging operation.

[La Guerriere]

Chain blocks are great things. Standard 2 tonne chain blocks (probably made in China) are very cheap. I've even seen them on promo in LeClerc. Used one recently to heave up a new staircase.

[Nick Trollope]

Talking about millstones, anyone want to come and remove my Family?

 

[just john]

A decent couvreur/charpentre would use a Manitou so there's your first call for advice.

Edit: You might find this useful for background to how millstones are moved regularly
(millstones weigh between 1 and 2 tonnes incidently) -
http://www.angelfire.com/journal/millrestoration/millstones.html

[jehe]

Stones 1.5m x 20-25cm

Floor 5 x 6m

2.5m to both ceiling and ground floor

Manitou would be easy, but we'd need either a new and very large window, or a new roof!

Chain blocks would be okay to lift them up, however, we need to then move them sideways a couple of meters to be lowered down through the floor somewhere.

This is a real head scratcher! Thanks for all your advice so far.

[NickP]

Two RS J's, some small scaffold tubes to lock the RS J's down  and of course keep them in place on your existing beams,  then have chain tackles on sliders, also webbing strops, simple. It all depends on how much you want to preserve the stones, if not it's a kango hammer but that would be a shame.

[La Guerriere]

Also could use scaffold tubes as rollers.

If all fails, use the ancient Egyptian method and hire 200 Nubian slaves.

[jehe]

The thing that really puts a spanner in the works is that due to the terrible condition of the beams underneath, I've no idea what will happen if I shift the weight across the floor. Chain tackle on sliders could work, but how do I know the ceiling above can take that sort of weight?

[NickP]

jehe,

I'm afraid you need professional advice mate, I spent 40 years shifting, rigging, lifting and lowering heavy machinery and it's impossible to guess what can be done without seeing a location. Also I'll go as far as to say if you are not confident about doing it yourself, leave it alone. The results if it all goes wrong would be too awful to think about. Sorry to sound pessimistic but unknown quantities equal danger.

[La Guerriere]

As always a few photographs will help.

[just john]

[quote user="NickP"]jehe, The results if it all goes wrong would be too awful to think about. Sorry to sound pessimistic but unknown quantities equal danger. [/quote]

Surely, better a bit of professional advice and a bit of a bill than . . .

''people lifted and flipped them with large wedges and pry bars. If you dropped them they would end up in the mill's basement taking out everything downward in its path. So for a long time millstones that hurt or killed any one were considered unlucky or evil, like a wild animal in a cage. Once it tasted human blood, it would wait around to attach some one at the next chance it had. So perfectly good millstones were retired out of the mill and became tombstones to mark the graves of the last person they killed.''[Www]

Edit: In the earlier url I posted there is a photo and construction diagram of a typical millstone crane to lift the stones,

[Gluestick]

jehe:

There would seem to be the following options:

1.  Leave the whole building until degredation of the supporting beams collapses the floor and brings the stones to ground level:

2.  Break them up in situ: having firstly reinforced the lower floor beams with Acrow type jacks, baulks of heavy timber and etc:

3.  A combination of .2., above and moving the stones sideways and lower them to ground level using a Yale Type (e.g.) chain hoist and an A Frame support, made from scaffold poles:

I once lifted a 1 1/2 ton rolling road dynamometer from a flat truck to floor level and moved it laterally a good distance across a workshop floor using lengths of scaffold pole as rollers and crowbars to provide necessary force and dropped it into its pre-prepared "pit": fortunately, huge RSJs were conveniently sited in both essential places: above the truck and above the Pit. The Yel type chain hoist was rated at 5 tons (Conservatively).

This provides not only some fascinating reading, but some ideas.

See here:

 

[Chancer]

Can't you just light a fire on the floor below? [Www]

[just john]

What goes in, must come out; these stones were frequently replaced in a Mill's lifetime so provision would have been made for this eventuality and a little bit of detective work must show a route out of their position and out of the mill; also easily enough for replacements to go back in with little more than hemp, pulleys, man and real horsepower[geek]

 

[Gluestick]

Ah!

But that 'twere in good old days, JJ.

Now, so a client in formed me last week, apparently any one working above 1 metre from the ground must enjoy the pleasure of scaffolding, in the cause of 'ealth 'N safety gone mad.

Wonder how the scaffolders manage to erect the scaffold then?

And must make interior decorators lives sheer hell: as well as their customers!

[Www]

[pachapapa]

The stones would have been swung out with the mill crane then lowered with hemp rope blocks through trap doors.

The largest of the stones at 1.5 m X 0.25 m will only weigh 1.25 metric tonnes and it has a hole diameter higher than the centre of gravity so a fairly stable lift.

I dig the hypnotic animation in the URL above.

Sheer legs could be placed through the floor for suspension of a block.

[NickP]

[quote user="Gluestick"]

Ah!

But that 'twere in good old days, JJ.

Now, so a client in formed me last week, apparently any one working above 1 metre from the ground must enjoy the pleasure of scaffolding, in the cause of 'ealth 'N safety gone mad.

Wonder how the scaffolders manage to erect the scaffold then?

And must make interior decorators lives sheer hell: as well as their customers!

[Www]

[/quote]

I'm afraid Gluey old son that your client is not correct, if he was then theatres, auditoriums and concert stages etc. would be closed down immediately. 'elth 'N safety as you call it, is not really the ogre that some people like your client and your favourite newspaper the Daily Mail [:D] would have us believe. OK they have come up with some howlers; but when corrected by experienced practitioners in lots of different trades they have sorted the theorists out, and after listening to the  experts, the guy on the shop floor, they have put into place guidelines which are beneficial to all. The most stupid followers of nonsense practises are weak management who are bullied by their insurance companies, most who wouldn't know what a days physical work is if it hit them in the face, let alone know the dangers faced by an average construction worker. I speak as a person who was considered expert enough to be asked to give my advice to Lloyd's of London, when they were issuing guidelines on the safe use and  working practises of  heavy moving machinery in the industry I work in. [B] [B]

[Gluestick]

[quote user="NickP"]..........your favourite newspaper the Daily Mail [:D] would have us believe. [/quote]

There you again: huge and gross assumptions.

Anything for a quick passing snipe.

As such an "Expert" it's really a shame you can't make any helpful and practical suggestions to assist and guide the OP.

Which is, unless I have misunderstood the purpose of this section of the forum, its raison d'être.........

Perhaps, as the resident expert on such matters, you can explain why UK contractors are now demanding scaffolding, merely to replace felting to flat roofs on single story garages?

Wimps?

Can't read?

Profit?