Wattyl 7008 and low temperature

[snowyskiesau]

I've just finished laying a green tongue floor which I'm going to finish with several coats of 7008.
Wattyl warn about not using 7008 if the temperature drops below 10 degrees during drying time. Current minimum temperatures in Sydney are getting close to that.
I don't want the leave the floor as it is for too long so as to avoid marks and stains from traffic.

Any experiences out there in applying 7008 during winter?

[journeyman Mick]

The problem is not just low temperature but a combination of low temp and high relatuive humidity. As the temperature drops you reach the dew point and the atmospheric moisture settles (dew). This will cause a white bloom in the finish, this is basically water trapped in the finish. This white bloom will occure before dew actually forms. It's also exacerbated by the solvents evaporating out of your finish as it cures as this drops the temperature of the surface to below the ambient air temperature. I have tables somewhere that I can post which help you to work out when it's safe to apply finishes. You'll need an accurate way of measuring your relative humidity though, a wet bulb thermometer at least.

Mick

[graemet]

Snowy,
(Many) years ago, we used to use 7008 - 2 pack estapol - on racing dinghys. These were always built during the winter so they would be ready for the first races in September.
Get everything prepared the day before, get a heater going early in the morning and get the first coat on as soon as the room is up to 15 Deg. From memory, the drying time is (was) about 3 hours at 25 deg. so keep the heaters going most of the day and you should be OK
Cheers
Graeme

[snowyskiesau]

Thanks for the feed back. This is the first time I've used this product and I want to get it right - a bit too expensive to make mistakes!
The wattyl data sheet states 4 hours to touch dry, recoat between 6 (min) and 24 (max) hours, with full cure after 3 days. This is for 25 degrees and 50% humidity.

I'll check out the temperatures early in the morning and see how it looks.

[durwood]

The reason they tell you about the temperature is that if it is too cold you will stop the two pack material from reacting and it will slow down or completely stop the setting of the paint.

Below 15 degrees the amount of heat in the air is not enough to make the estapol harden. If you can get any source of heat to warm up the room to above 15 degrees it will allow the material to set. Don't put a infra red heater near the timber as it will apply the heat to the estapol and the wood being a poor conductor will ensure all the heat is transfered to the estapol and the moisture in the wood. You may end up with the clear blistering. Put it somewhere where it just warms up the room but they heat close to the heater and not too well away from it.

The best answer is a convection heater which will pump out warm air into the whole of the room so all the job dries evenly.

As the estapol is a slow drying material it will not get blushing ( white coating on the surface ) even if its raining. If it was a fast drying lacquer you wouldn't think about applying it in cold or wet conditions. Obviously the better the conditions the more likely you won't have problems.

The warmer the temp the faster the Estapol will dry but the Estapol is designed to be used when its a normal temperature which for most of the time is between 18 to 25 degrees. If its hotter it dries too quick and as they have stated if its too cold its no good either.

By the way if for some reason you mix a two part paint up and then find its not a good idea to put it on, then you can put it in a sealed tin and put it in the fridge overnight. If its not your beer fridge in the garage a sealed plastic bag as well would be a good idea.

Take it out next day let it come back to room temp and then you can apply it. Once mixed you normally have about 4-6 hours to get it on less when its hot longer when its cold because the temp controls if and how long it will take to cure.

Keeping the room warm and also having good venilation is going to be a problem if its lousy weather. Try to do it on a nice day which will allow you to open the windows and not drop the temp too much, so a cold windy day would be no good, watch the fumes 2 pack paints can make you pretty sick if you get a good dose of them.

[snowyskiesau]

Not a good day to start the process. Raining all day, 98% humidty and the lowest maximum temperature for 10 years.

On the bright side (?) the rain did reveal a leak in the roof of the newly floored room.

[durwood]

why not wait for a few weeks, it will be warming up by the beginning of September.

If you can put something down to stop the floor getting dirty (plastic or lino etc) for a while it would guarentee a better result.

Warm temperature, windows and doors open whilst doing the appliction and no worries about drying.

[snowyskiesau]

I think waiting a few weeks is a good idea. I have a few sheets of ply I can put down to protect the floor from marking.
If I'm careful, I should be able to paint the wall and ceiling without too much mess, they've already been prepared.
It will also give me chance to find the leak.

[snowyskiesau]

As the weather in Sydney is a bit warmer now, I applied the first coat of 7008 today.
The green tongue soaked it up like a sponge and I had to mix more to finish the first coat.
The finish is matt which I'm assuming will change once I get more coats on (I've planned on 4 coats total)
The floor colour is much darker now and looks exactly the same as some cork tiles I have, just as some here had said it would.

Cleaning up is a bugger. I used a mixture of 7008 reducer and metho as recommended but I've a feeling that the applicator will not be usable again.
Now if I could just do something about the smell...

[maglite]

Did you break the mix down 50/50 with reducer for the first coat?
My experience with 7008 is that drying time is not so much the issue if the room can be sealed and the product left to do it's thing. The bigger issue with open ventilation is dust settling on the finish before it cures.

9 times out of 10 the applicators will be US after the coat irregardless of the amount of reducer mix that you clean them with..........It always seems to be the edges or some parts of it that get clean but you never manage to remove all of the product.

A good way to minimise the use of the lambs wool applicators is to apply the product with a mohair roller and then use the lambs wool applicator to smooth the finish out, though I have been told that the mohair roller works quite fine by itself but I have no tried it.

Cheers
Steve

[snowyskiesau]

I did use reducer for the first coat.
I've done the second coat and the finish is now gloss.
The amount I had to mix was less than for the first coat so it's obviously not soaking in as much.
A light sand in the morning and then the 3rd coat.