Varnish woes again

[J. Dillon]

http://www.imagestation.com/picture/sraid44/p88b4846dcd42ba276d26b280e8d59ed0/fce027d3.jpg

Does varnish have a shelf life ??

Last used this can in Aug.02 about 3/4" fom the top to apply a touch up coat to "Carrianne's " bright work. When finished, sealed the can tight with mallet blows to the lid.

Opened it up fri. to start applying varnish to my repairs and removeable brightwork.

Shocked to see the above. :eek: Below the creamy hard crust is a useless goo. This happened before with a can half full. I assumed at the time I didn't seal the lid enough and remembeming this was more diligent in lid sealing but apparently not enough,.... unless something else is going on. :( :(

Any ideas ?
:confused:
JD

[Scott Rosen]

Once you open the can, you allow fresh air in which starts the curing process. The best way to avoid those kinds of problems is to keep the can open for as short a time as possible. Even for small touch-ups, you should open the can and immediately decant the needed amount of varnish into a separate container. Then, using a foam brush, make sure that there is no varnish in the lip of the can. Then replace the top. I like to press the top carefully into place by hand so it seats evenly. Then I will tap it lightly with a hammer working around the circumfrence of the lid. Only after you've done all of that should you proceed to actually apply the varnish. In that way, the can will be open for just a few seconds.

[Ian G Wright]

,,,,,,,, and store varnish upside down.
IanW

[NormMessinger]

My theory on why there are so many different methods of keeping varnish or paint from skinning in the can is that each brand reacts differently. Some will skin no matter what one does and some will not skin after months in a half full can. Some things work some times and nothing works all the time.

--Norm

[Art Read]

What they said... I always feel a little trepidation every time I re-open a can of ANYTHING after any length of time has gone by. Same product, same "technique", different results. Almost invariably. Deks Olja is notorius for this. One can, a quarter full, left on the shelf for six months will look brand new. The next, three quarters full, left two weeks looks like gelatin! (The good news is that, with Deks, it seems to work fine anyway if you make sure to brush or wipe the "lumps" out...) With varnish, If I see what you've got there when I open the can, I'll try decanting it to see if anything that looks like varnish is left and then just use it for "sealer" coats or coating bungs. Lot to be said for using it all up at once, but that's easier said than done in the real world...

[Concordia..41]

Ugh! I've had some (almost all if given enough time) skim over, but never had anything go bad like that????

I have been storing upside down the last few months. Too early to tell if it's going to make a difference, except for the can of Helmsman which didn't have the lid on as tight as I thought :eek: :eek:

Oh well, not only are they upside down, they're upside down in plastic tubs (which I highly recommend for anything with potential spillage). Other than the annoyance at myself, no real harm.

Regards -

[thechemist]

For varnish to go white [opaque] I would think it got some water in there, likely condensation via an imperfectly sealed lid and storage in a dock-box, unheated garage or other wretched environment.

I have a two-year-old partial of Captain's in the lab. The lid was sealed but not airtight, and it looks normal.

Dunno what you got there..... :eek: [I really need a graemlin bending over and vomiting, but can't seem to find one]

http://ultasail.com/pic/puke.gif

Thanks, Capt. Jake.

[ 12-29-2002, 11:35 AM: Message edited by: thechemist ]

[capt jake]

http://ultasail.com/pic/puke.gif

[paul oman]

Cannot say I've tried it with varnish - but one of my 5 minute epoxies forms a skin after opening if there is an air space.

I've solved the problem by using a squirt of propane from my walmart propane torch before I close the lid... The propane seems to form an air blocking layer over the product.

paul
progressive epoxy polymers

[Concordia..41]

Margo forgot to mention that the can of Helmsman varnish was my can that has been around since 1996. It was last used on a 31’ Jersey Sport fisherman that I had at the time.
It had been out in the shed since then and I took it down to Sarah to use for setting screws. I use varnish to lubricate the screws instead of soap or oils. After all that time it did have a light skin over the top but was not white or milky. The grove in the can was full of hard varnish and the can was bent so the lid did not seal well. I just punctured the skin and poured some in a plastic buttercup with a lid and placed the lid back on the can as good as it would fit. The varnish in the buttercup will skim over and will get thick under the skim and I use it for the screws and bungs. When it gets too thick I just get another cup.

While changing the canopies around and cleaning up around the boat, Margo decided to take some stuff home to the shed and claimed the Helmsman varnish, she said it was hers and put it with a lot of her varnish and thinners in a plastic tub. I believe she has at least 1 can of every varnish know to man. Of course she turned it upside down --- BAD move. At least it was in a plastic tub as she put it in my car, which she also claims is hers…..

Storing paint, varnish, epoxy or anything that settles upside down is good only if you rotate it on a regular bases, other wise you have defeated the purpose which is to keep the solids suspended. This still will not keep the oxygen in the can from trying to cure the top layer of the varnish; it just keeps it mixed up if you rotate it often enough.

By the way if Margo ever asks, her can of Helmsman varnish is in the laundry room, un-opened where it has been for the last few years!

Just remember the one thing I discovered at a long time ago – What’s hers is hers and what’s yours is hers!

Dave

[Rich VanValkenburg]

Looks like moisture and a bad seal, as the chemist said. I've had that happen a couple times. Now, I try to wipe the can and lid as clean as I can, then a heavy thumb in the middle of the lid usually lets me press it in place without a hammer. This also seems to create a bit of vacuum in the can, which appears to help keep a heavy skim off. If I have a few cans 1/3 full or less, I get a new, empty one from the orange store for a buck and change, thin, then filter the heck out of my leftovers into the new can. (label it)

Rich

[Concordia..41]

http://64.207.13.28/mysmilies/otn/angry/zx11pissed.gif

For the record:

</font> He had no business setting bungs with perfectly good varnish when I've got several old cans down to the last inch of dregs.
</font> I do not own every varnish in the world (haven't tried Stopanni [sp?] yet).
</font> I guess the plastic container was his too... </font>- M

[Dave Hadfield]

I have taken to upside-down storage too, as Ian recommended. It works.

One of the advantages is that no liquid stays and dries out in the rim.

I pour the varnish through a fine filter into a dead-clean cup, put the lid back on the can, stand on it three ways to press the lid down firmly, and set it on the floor upside down to let the varnish in the rim flow out.

Then, later, when I'm satisfied it's not leaking, I put it on the shelf.

Of course putting decanted varnish back in the can is not a good idea -- something to be avoided if possible.

Just my 2cents....

[videoguy]

One trick I have been using for years is just before I close the can I take a deep breath and
hold it for a bit .then I hold the lid just over the can and exhale into the can and close it real quick. Your breath displaces the oxegyn in the can
so the varnish cant skim over. It works great ...............Phil

[NormMessinger]

Anybody ever tried pouring chicken soup on the surface to prevent the stuff from skinning? "Well, it can't hurt."

--Norm

[capt jake]

Norm..... http://ultasail.com/pic/puke.gif

LOL :D

[Wild Wassa]

JD, Yes, paint has a shelflife and it has a different shelf life once opened. It might be old when you buy it. Don't ever buy a can of paint that has dust on the lid.

I notice that there is damage to the can's lid. Possibly a less than perfect seal. Opening a can, I do very slowly, I release the pressure very slowly and uniformly around the rim. Do you have a gass heater in your studio ?, moisture, looks like it has 'played a part'. As mentioned by the Chemist and Rich.

The things that you can do are, reduce the volume of air above the paint, number one. Glass marbles replace the volume. Who still has their marbles?

Number two, lay glad wrap over the paint surface, check this, you don't want to dissolve the gladwrap. Short term only, half a day to a day. Sometimes I don't want to place the lid back on too tightly, until I've finished. Paint cans are really flimsey now days, the lid is the weakest point.

Number three, the best, no wastage involved, invert the paint can, as already mentioned by so many, smile.gif . G'donya.

Number four, but more expensive. Purchase paint in smaller quantities. This has become my standard practice. 5 lts of paint breaks down into 2 x 2 + 1. If I can break a litre into 500 + 500 ml, I will. I can't afford not too, with Canberra's temperature, being so high. If I have to 'box the paint', .... all bets are off.

Warren.

ps, Number 5, follow Scott's advice, I always do.

[ 12-29-2002, 11:18 PM: Message edited by: Wild Wassa ]

[jason stumpf]

i'll second the clear plastic wrap. get yerself a roll, or steal one from the kitchen. when you're done with your varnish (or paint) pour a little bit (spoonful or two) of thinner on the surface of the varnish (you can use boiled linseed oil in a pinch too if its oil-based). then take a piece of the plastic wrap and arrange it inside the can so that its just touching the surface of the varnish, as well as sealing around the sides of the can. i learned this from an old-old-timer, and its worked very well for me.
jason

[Buddy Sharpton]

I know this sounds high tech, but....
I have about twelve different varnishes and enamels involved on the boat and associated signboards and rigging, so lots of little cans in a box for touch up. There is a miracle cure, an aerosal can of Nitrogen gas. I got mine from Highland Hardware, sells for about $12 as I remember, and will "do" about 70 cans with a four second blast each. You squirt it under a cracked lid (sorta like a can of WD-40 with the skinny red tube) and close the lid.Works much better than the exhale the CO2 routine. Absolutely pristine liquid when you reopen. At what paint costs these days, its absolutely a bargain to me.

[mhoffman]

Someone mentioned on a previous thread they sucessfully used emptied and cleaned bags from thsoe boxes wine comes in. No moisture or oxygen introduction as the the varnish empties out. I haven't tried it, but it seems economical and practical...
Matt