unpleasant surprise behind wallpaper

Stephen coughed up some electrons that declared:

Perhaps an orbital sander might blend the paint edges in enough. Otherwise lining paper would be the normal solution.

Have you enough spare new paper just to hang a piece and see how it turns out when dry? Unless the paper is really thin and fine, I wouldn't normally imagine paint on plaster would show through.

Cheers

Tim

I _thought_ I'd get away with hanging paper over a surface like that - I didn't - it showed through.

Polyskim and a sander is your fiend

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

Rough little devil.

Heavy duty lining paper, no question.

Tasmanian? ps Did you really mean to use an angle grinder :-) ?

In message , Tim S writes

Need to be wary of doing this if the house is old, possibly lead based paint.

On a wall? I doubt it. Woodwork, yes. Walls and ceilings used distemper.

Or skim with filler if your plastering skills are up to it. I prefer it to the Polyskim finish and it holds up very well in a thin layer.

In message , "Dave Plowman (News)" writes

Wouldn't want to put money on that, I'd definitely do a lead test before sanding it down if it appears to be . Just because it *should* be distemper and lead based pain *should* only be used on woodwork...

I've seen painted plaster in houses around here (1930s era) that was definitely not distemper. It's cheap insurance to find out before you start sanding on unknowns.

Oh FFS. Lead isn't that poisonous.

It wasn't lead either.

It's cheap insurance to find out before you

Agreed, it is repeated exposure that could be an issue. There is an issue with young children who could ingest lead containing dust.

This issue is just as overblown as the nonsense about asbestos and mercury from CFLs these days.

OK, fair enough. I'm quite happy for you to go fill your lungs with it.

I know it's not that bad in small one off doses but I choose to be careful, I have small children around here and would take reasonable care to identify unknown paints, a test kit is cheap and the houses are old enough to potentially contain lead paint.

Possibly not but not being a paint chemist or expert in the identification of unknown paints I rationalised that actually knowing would be better than taking a chance given that the test kits are fairly cheap. Care to tell me how you know?

How many old houses have you worked on? Lead paint was *far* more expensive than water based stuff and no one with any sense would use it on an ordinary plastered wall. Only one you might find it on is direct to brick.

My comment applies even more to houses of that era.

It makes sense to take precautions when sanding anything.

Because I remember how lead paints look and feel.

It can't be all that bad if the government is willing to put amalgam fillings in your teeth!

As part of some purely private research into as it happened, nuclear energy, I had occasion to attempt to understand issues surrounding toxicity limits and teh handling of 'dangersous stuff'

Now, from rusty memory, it seems to go like this

Substance X is identified as being a health hazard because people or mice have been shown to die more readily when heavily dosed with it. Substitute lead?mercury/plutonium or whatever for X.

A graph of mortality over levels of substance X is drawn up.

A level such that any death over random would be totally buried in the noise, and assuming linear extrapolations of high doses to zero doses is valid, is set up. Usually so that the level is less than 1% of the level that produces ANY noticeable change in mortality or indeed in health.

So at that point the "recommended dose" is in fact about a hundred times less than that which does anything detectable.

At that point, the legislation kicks in, and every use of that material that could conceivably result in exceeding that 1% limit is surrounded in dire warnings, safety equipment and the like. Viz most of us lived happily with asbestos for years, and haven;'t died yet: deaths were largely occurring in people who had high and CONTINUOUS exposure to it. There is a large body of evidence that suggests that the body is in fact quite capable of ridding itself of poisons provided the systems are not overloaded by continuous high exposure.

And finally, if there is no commercial reason to keep on using substance X, because better (and presumably safer) substances exist, then its banned from general use. This is very much the case with mercury thermometers and barometers, asbestos in insulation and brake pads, and lead in petrol (which WAS actually a Bad Thing in urban environments and did cause detectable problems. Not half so much as diesel particulates do now, mind you).

Lead in fishing weights has also been banned, because eating a bloody great ball of lead DID kill wildlife.

IO am not sure anyone has ever died, or become ill as a part of ingesting lead paint.

Or small quantities of mercury, either. The people who suffered were hatters, who used it on a daily basis, or miners..

The point here being that most of these so called 'dangerous' compounds are not. Not in the very small and very occasional exposure to which we might be subject: The Law is there because of pretty suspect and very extended extrapolations from very sketchy data, for which there is very little evidence that the extrapolation is in fact justified. So the Law errs way on the cautionary side, as do all the dire warnings.

There is a world pof difference between 'failing to provide proper labelling on a product which might just, if gallons were ingested, prove fatal' and being harmed by a splash on your skin, or a moments fume inhalation..

As with all things, context and perspective is important.

Apropos nothing much, have a look here

Is that your perception however?

In message , The Natural Philosopher writes

Ahh, you have an advantage over me, I don't have that experience hence the use of test kits where I'm not sure and sanding/dust creation is unavoidable.

That sounds exactly like the passive smoking argument...

(hides behind sofa)