Reusing white spirit - quickly.

[dedee]

Is there any way I can speed up the process of paint settling in white spirit?

I'm halfway through painting 5 wooden doors each is needing at least 3 coats of undercoat and I guess 2 of gloss. As I can only paint for 90 mins each day in the morning and only 3 days a week it is taking me ages and I am forever cleaning the brush and using a lot of white spirit. Some of the used stuff has not settled after more than 2 weeks.

Cheers

Andy

 

[Chris Knight]

Andy,

I would just try filtering it through something suitable -Valeries tights? On second thoughts a bit of cotton sheeting is probably a better bet..

 

[dedee]

Thanks Chris,
I hope your shoulder is back to normal now.

I really should have thought of that as I have used the old tights method for filtering out the crud in old paint.

I just decanted 6 jam jars of used white spirit though 4 layers of what I hope is an old old pillow case - still comes out very white but will see our quickly it settles.

Andy

 

[Steve Maskery]

I've not tried this, but I wonder if adding a bit of copper finings would do the trick? You'd have to ask a friendly brewer for a bit, but I would have thought it was worth a try.

I just decant all the used stuff into a plastic bottle and put it on the shelf and forget about it. Whenever I want some, there is always a supply of clear, if yellow, turps ready and waiting.

S

 

[studders]

Don't try using Coffee filters.

Been there, tried and failed.

 

[Jake]

Borrow the chef's trick of simmering egg white in stock to bind up all the small particles in suspension.*




*best hold your breath throughout and call the fire brigade in advance so they are in attendance throughout and don't blame me if they aren't happy or if you blow yourself/your house/your village up

 

[wobblycogs]

I've never tried filtering white spirit I always just let it settle out (now you mention it though I feel a bit stupid for not having thought to try it).

Anyway, back in my chemistry days I would probably have used a Büchner flask http://en.wikipedia.org/wiki/Büchner_flask filtration system for a job like this. Looking at the photograph in that link... the ceramic bit on top has numerous holes in it and a single piece of filter paper it placed over the top. A vacuum source is attached to the hose connector sticking out the side of the flask. With the vacuum going a little of the mixture is poured into the top of the filter to wet the filter paper which makes it stick to the bottom of the ceramic part then you can pour the rest of the mixture in the top pretty quickly (filling the ceramic section).

The vaccum source we always used to use was a venturi system as shown here http://www.sinc.sunysb.edu/Class/che133/techniques/suctfilt/suctfilt.html (actually this link describes the idea rather better than I have).

There's even one available on ebay http://cgi.ebay.co.uk/500-mL-Pyrex-...Equipment_Lab_Supplies_ET?hash=item4a9ddb06ac although I imaigne it's fairly easy to put one together yourself.

 

[kasandrich]

Why do you need to fiter it? you can clean a brush in white spirit which has traces of paint in it (ie. its white) without an issue.

 

[dedee]

I think I'll skip the flask and vacuum - I failed chemistry at school.

I'd be interested to know why coffee filters did not work as I was going to buy some to try.

I know that I can just wait for the sediment to settle but that takes weeks and I have about 5 litres of the stuff waiting to "clear".

I do use old, unclean spirits to start with but like to finish with clean spirit to insure there is no buildup of old paint in the bristles - I then finish off with washing up liquid and a rinse in hot water to keep the bristles soft.

Andy

 

[wobblycogs]

My guess would be that coffee filters would block almost immediatly because the solid is quite gooey. Gravity filtration works well when the solid is hard like coffee grounds but a softer solid needs a bit of suck to draw the liquid through.

The alternative option is to centrifuge the liquid. It's not as easy to set up as filtration but it's great for getting very fine and delicate solids out of suspension. For example biologists use it to separate DNA from liqud after they have extracted it from cells. Just put the liquid in a sealed pot, tie a rope to it and spin it round your head. The longer the rope the faster the separation but the harder it will be to spin. You have to be careful not to disturb the liquid when you stop though or you will mix it all up again. You could build something to do this for you but you've got to make sure you counter weight the pot.

Failing that I don't think you will do much better than a pair of old tights or just leaving it to stand

 

[studders]

My guess would be that coffee filters would block almost immediatly because the solid is quite gooey.

Got it in one.

Starts off fine but after a few seconds it gets to a dribble then pretty much stops altogether.

Ho hum.

 

[CNC Paul]

Andy,

You need a Brush Mate, these are containers that have a vapour pad which contains a liquid that dispells air. You hang the brushes inside the container between uses, I have a large one that will hold about 20 brushes but you can get a small one that holds a few brushes.


http://www.brushmate.co.uk/productsummary.html

 

[dedee]

Thanks Paul, I'd not seen or heard of that before. Looks too good to be true.

Certainly for storing brushes while a job is ongoing it looks excellent.

There seems to be a lot of good reviews elsewhere too.

It will go on the list for the next supply drop (easter) unless I can find one over here.


Andy

 

[studders]

Thanks Paul, I'd not seen or heard of that before. Looks too good to be true.


Andy

Been around over here for years, a lot of trade painters swear by them. If only they could make one that took water based paint brushes as well, I'd buy one without hesitation.

 

[monkeybiter]

any contaminent that is dissolved in the solvent, as opposed to particulates suspended in it, will not filter out or separate with a centrifuge. removal of disolved contaminents would probably be uneconomic.

 

[pren]

When I'm painting things with a day or so gap between coats I cover the brush or roller with cling film or one of those wee sandwich bags. I've found that as long as you squidge enough of the air then the brush stays 'wet' for up to 2 days. No need to wash it everytime. 8)

 

[petejefferies]

you could try this:

http://www.spiritreclaimer.com