Replies

1. 
   UncleDunc | Dec 01, 2002 09:25pm | #1

   You can fill the empty space in the can with some inert gas before you close it. The most convenient choice is probably Bloxygen, in a handy size spray can sold for that very purpose. Look in the finishing section of all your woodworking catalogs. I've seen their ad in FWW, but I can't remember if it's been in FHB or not. Other choices are carbon dioxide, nitrogen or argon, all available at suppliers of welding or industrial gasses.

   Another approach is to exclude the air mechanically, either by storing the finish in a collapsible container or by adding clean, non-reactive objects such as rocks or glass marbles to the can to raise the fluid level.

   Another suggestion I've seen is to cut a circle of slick paper out of a magazine (not FHB :) ) the exact size of the inside diameter of the can and float it on the finish before closing the can. I don't know if this is supposed to work by preventing the formation of the skin or just make it easier to remove after it forms.

2. 
   fredsmart48 | Dec 01, 2002 10:45pm | #2

   You can make your own co2 vinegar and baking soda. Put the two in shallow dish inside a 5 gal. bucket let it react in the bucket when it is done set you open can of finish in the bucket the co2 is heavier then air it will stay in the bucket It will displace the air in bucket set the can of finish in the bucket so co2 can displace that air also now put the lid on finish.

   Should work, never done it my self.

1. 
   suntoad | Dec 01, 2002 11:46pm | #3

   I've been plagued in the past with this very problem using the very same product.  I've used over 6 gallons of Minwax Poly in my house to date.

   What I used to do was shove a piece of cellophane down over the surface.  It helped but did not eliminate the prob.  What I do now is use smaller 1-qt. cans.  When I open a new gallon of Poly, I divide it up into the 4 quart cans and seal them.  Then I only use one can at a time.  Only the can I'm using can skin, but it almost never will...not enough air space, evidently, in these cans to cause a skin to form.  Problem 95% solved.

3. 
   Piffin | Dec 02, 2002 12:20am | #4

   It is definitely the oxygen you let into the can that causes this because this oil finish is a reactive cure rather than evaporative. Any of these suggestions should work. I use the Saran wrap method because after tucking it in to the surface of the oil, I have some tails that I can use to peel it up again.

   If you use the divide and conquer method of putting it in smaller containers, be very sure to mix and stir well first, especially if it isanyuthing other than high gloss. All of these start out as high gloss and then the satin or semi-glosses recieve varying amounts of de-glosser which settles to the bottom of the can. You could end up with a very uneven appearance using from cans with differing mixtures of de-glosser.

   .

   Excellence is its own reward!

   "The first rule is to keep an untroubled spirit.

   The second is to look things in the face and know them for what they are."

   --Marcus Aurelius

4. 
   DaveHeinlein | Dec 02, 2002 12:34am | #5

   Make sure the lid is on tightly and store it upside down

5. 
   Dachiko | Aug 30, 2024 10:48am | #6

   Hello i have problems regardin RTV POlyurethane, Especially with part B
   When i open aluminium lid and pure in to the 1 kg pet bottle, it still become thicker after a while, that's made it impossible to reuse the liquide in a second or third time. How can i solve this problem.