Several years back I read an article on storing leftover paint/stain/varnish etc.
Seems to me you had to replace the air in the can with nitrogen and this prevented the contents from skinning over or changing into granite.
I do have a nitrogen tank but it is 3000psi and even with the regulator it only gets it down to 600psi; naturally I am reluctant to try this considering the price of rags.
Finishes here on the island are very expensive; that is when you can find them; usually you are looking at MT shelves; so you have a tendency to save leftovers even if it is just a couple of spoonfuls.
Anyone tried nitrogen or what’s your favorite gas??
Replies
I'm guessing it is the oxygen of the air that reacts with the paint to form the skinning over. So it would follow that any non oxidizing gas that you could put in the can would avoid the skinning over - ie He or CO2. Is there any way that you could let just a small jet of N from your tank so it wouldn't spatter the paint all over?
A traditional method calls for filling up the extra head space by placing clean marbles into the can until the fluid displaces the gas.
You are right Tinkerer; oxygen is the bad guy in this equation.
Helium is lighter than air (I think); I flunked ballooning
CO2 has that O in it; I also flunked chemistry miserably several times but I dont think it will work.
The minimum pressure from the regulator is 600psi; you can adjust upwards but not down.
Yea, Helium would be a bugger to pour into the can. But CO2 should be okay as the molecule is very tightly bound and very stable. Like water (HO2) but, of course, it is not a gas.
I think the US is the only producer of helium; scarce here; but nitrogen is in every hangar; well we dont actually have a hangar yet but the cylinders are here.
Just testing.
Edited 11/2/2009 11:34 am ET by Tinkerer3
Tink, I see you got the Attach Files thing figured out, cool! Great building too! Waaayyyyy too big though (the pic, not the building) LOL. 3 MB takes awhile to download, even on a cable connection (us American's we want it now!
Your resolution seems to be set high -- you should be able to change it on your camera to...hmmmm....a Medium setting maybe? Different cameras, different ways.
I've attached an ~89 Kb file below, same pic, much faster download. Fits in the Knots frame too, at least on my monitor. Did you get my reply to your email??
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Edited 10/31/2009 10:56 pm by forestgirl
FG,
You weren't supposed to see that. I hid it in a 2006 thread that had run out eons ago. Oh well, now that I've been exposed, I'll try some again. I think I got that picture from a different file where all the pics have been enlarged so where the whole screen will not hold them. Hope no one else notices.
Tink
That's really funny, Tinkerer. Taunton's software makes it hard to "hide" LOL! It came up in my "Unread Messages" list and since the icon indicated I had posted in it, I just had to peek and see what was up!
You doin' OK figuring this stuff out? I never did hear whether you got my replies or not.
PS: The new attachment in your last post was in .bmp format. That's an uncompressed format, you'll want to get in the habit of posting in .jpg instead, or most pics will be too big (file size, not "screen size").
forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Edited 11/2/2009 4:39 pm by forestgirl
Yes, I think I have gotten all your messages. Can't find the last one on the computer but I have a printed copy that I'm still studying. One question - how do I get a post in .jpg instead of .bmp. I think I am reducing the size in "In Fan View". Is that the program you were asking about?
We have thoroughly hijacked this thread. Will we be in trouble from the original poster or the powers that be? Got piles of leaves three feet high to get off the yard. This is the fourth time I'm taking them off and hopefully the last. I blow them into piles then rake into a tarp to haul to the edge of yard to dump off. Thanking you for your help and stay cool. I haven't given up yet.
Tink
I'll send you an email later this evening. Just got back from a trip to Port Townsend, bought a few small hunks of wood to get started with my turning. Time for a nap!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
For viewing, you can right click on the picture and "open in a new window" so you can see a MUCH smaller picture.Gretchen
Thanks Gretchen, I shall try that. I have a lot to learn. Some day......, maybe.
I find that finishes last a long long time if you seal the can properly. What you must do is clean out the ring around the top of the can, so that the lid can fit down into that ring. Every time I use a paint can, that ring gets finish in it. If you just hammer the lid on, the liquid trapped in that ring prevents the lid from sealing as well as it can. Use the brush tip to get most of the fluid out of there, and then a rag or paper towel to get the rest out. If you do it right, the top of the lid will close flush with the top of the can, just like it did when it was new. If the lid is not flush, the finish will die in the can, garandamteed.
For newbies: Punching a few holes in that recessed part of the can-rim helps. I guess it's not a good idea with water-based, because the exposed metal can rust. I don't have much trouble with paint getting screwy during storage. forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
Before you complicate a not very complicated process, may I suggest you try the following:
1. Clean out anything in the rim.
2. Pound (tap gently?) the lid down until it appears to be seated.
3. Turn the can upside down. The contents become the sealer.I have 15 year old paint and varnish that I use for touch-up that works well. On rare occasions it skins over but the skin is at the bottom of the paint. The can is upside down, remember? When this happens, either be careful not to disturb the skin, or pour the finish into another container, cut the skin out, and pour the finish back in the original container.
FG ---
I've heard that trick, and I think it isn't as good as leaving the rim unchanged and properly cleaning out that groove. I think that the reason the lid is built the way it is is that the lid has two sealing areas. One is the outside face of that groove, and the other is the inside face. Solvents have to penetrate first one seal and then the other to escape. Punching the holes results in only one seal.
Jamie
Thank you Jamie,
I am probably the world's sloppiest painter and even if I do a perfect job of wiping the lid and resealing it, the problematic oxygen is still inside; if you use half a can of paint do you now have a half a can of air; the more air, the thicker the skin I think?? there is probably some physics formula out there for the air to skin thickness ratio; I also flunked physics; not quiet as miserably as chemistry; but you are right; a perfect seal is fundamental.
Favorite gas -- Air. As in scuba tank for exploring your beautiful reefs. Our ideal vacation is 4 day dives, 1 night dive, 5 days, then home to rest for a week or two to recuperate!!
81, you dont have to explain nitrogen to a scuba diver.
This evening I watched the flamingoes heading back to Venezuela; perfect in trail formation; gorgeous sight.
Brag! Brag! Brag!
Just kidding! Bonaire is one of our favorite diving locations. We especially enjoyed the ability to dive without a dive boat although most of our dives were by boat.
I had forgotten about the flamingoes and the salt industry. Anyway, we hope to someday return for more beautiful reef dives. At our age, we now forego the 90 foot dives (i.e. Cayman Islands) and stay in the 30 foot max range. More down time!
And we also enjoyed the food -- especially the imported beef!
A bad day woodworking is better than a good day working -- yes, I'm retired!
Are you sure it was beef; lots of wild donkeys on the island.
I thought donkey tasted like chicken! <GRIN>
A bad day woodworking is better than a good day working -- yes, I'm retired!
and no feathers to pluck.
I've never used gas, because it seems to me that there's an easier way to replace the air in a paint container. Put in a clean stone that takes up the volume of air and raises the level to more or less full.
DR
Excellent idea Ring; most of our stones are chunks of coral; very porous; now the Governor's mansion has these 2 canon flanking the front stoop; perhaps I could borrow a few canonballs.
S.K.: I bought my nitrogen set up to preserve fine wine in half used bottles. It should work for anything affected by the oxygen in air. There might be a kit for your regulator to change its pressure range. I started off with a regulator that puts out 0 to 50psi so a trickle of gas is easy to get. Duke
Kenneth Duke Masters
The Bill of Rights December 15 1791 NRA Endowment Member
LEAA Life Member
CRPA Member
Duke,
Can you get a kit for Guinness??
I might have a problem convincing the missus that the new wine preserver is for keeping the paint fresh.
Can you get these in a package store or Walmarts??; I'll be in the USA next month for shopping.
Dont know about low pressure regulator for this tank; I use it to inflate the landing gear struts on aircraft; tank is chained to a dolly; enormous.
S.K.: Sorry lost track of the "Guinness" reference. What I was getting at is if you have a pressure regulator that puts out a minimum of 600lbs of pressure you might get a kit to replace the regulators guts for a lower output pressure cheaper then a new regulator. Then it could be used to replace the air in half used cans of finish or half empty wine bottles. DukeKenneth Duke Masters
The Bill of Rights December 15 1791 NRA Endowment Member
LEAA Life Member
CRPA Member
Duke, the tank was $21 deposit (you trade in an MT for a full one), nitogen fill I think was about $15 (good for at least a year) and the regulator with valve fittings and hose was $150 and change.
I'm sure the regulator can be fitted for lower pressures but cost is an issue.
Meanwhile I'm using glass jars; fill to the very rim; leave no airspace and screw on the lid; a year from now when the lid has decided to marry the glass, simply punch holes in it and pour contents into a paint bucket.
Dont use pickle jars or anything garlicky.
S.K.: Jar idea sounds good, I'll try it next time I start a new can of something. DukeKenneth Duke Masters
The Bill of Rights December 15 1791 NRA Endowment Member
LEAA Life Member
CRPA Member
Duke,
Glass jars work good if you fill them to the rim or is it brim and get the lid on so that no air gets in. Screw on lids are the best.
I use magic marker to label the contents; clear finishes are difficult to I.D; is it varnish, maple syrup or that sample you forgot to take with you to the doctors??
Pressure regulator.
You know, if you could get the fittings, I think an oxygen regulator like used on a oxyacetylene welder regulates from 3000 all the way down to 0 psi.
Does anyone use small, empty paint cans that are available at HS and other paint stores? That way, they can be filled to the top and even if there'a a little air, it won't go south as fast as when it's in a gallon can.
"I cut this piece four times and it's still too short."
I've had excellent luck with the dust off sprays that come in aerosol cans for cleaning camera and electronic equipment. They are an environmentally friendly version of Freon gas. Some of these contain chemicals to prevent kids from trying to get high, I've only tried the untreated versions. The stuff we use is Fellowes brand and it was purchased in a Walmart photo department. The credit for this idea goes to someone who posted it here in Knots a few years ago.
In experiments in the Fine Woodworking shop we could keep Waterlox finish in jars for months when using the gas, the Waterlox would start to harden in days in air filled jars.
Another thing I discovered in the tests was that once a finish started to react, it would continue to harden even if you later added gas to the container, so the secret is to use the gas as soon as you open the new can and never pour finish you've been working with back into the container.
John White, Shop Manager, Fine Woodworking Magazine
Thank you John and the original contributor,
The missus and I will be in the USA for 3 weeks in May and Walmart is on the list.
I will certainly check out this dust off spray.
Dont know what waterlox is but I've heard the name; here on island we have 2 finishes............stucco finish in 3 or maybe 4 colors and oil stain in any color as long as you like mahogany; there was none left last week so I dissolved the skin in an old can and used that; hence the query.
By the way, the sun is heading north; it passed directly overhead last week; will give it a shove in your direction.
John, could you describe the procedure you used for filling the paint can with gas?
To use any air displacing gas the procedure is the same, just sit the lid loosely on the can, slip the tube from the aerosol can under one side of the lid, spray the gas in gently for 5 or 10 sec, and then pull the tube out and tap the lid firmly in place.
John W.
Thanks! Sounds pretty easy -- Go to Walmart, buy a can of gas in the photo dept., and you're done.
To whom what ever.
Buy a food vacuum machine ( Food Saver )and put the stuff in mason jars.After use put a lit on the jar and vacuum of with the gadget they sell for the jars.
I do the same with shellac and shellac flakes.
HilmarEdited 4/18/2006 9:28 pm ET by h12721
Edited 4/18/2006 9:29 pm ET by h12721
Danki danki for all the posts on this subject; lots of good ideas shared.
I have also used the computer dusting spray with Waterlox, and my results were not completely positive.
It did replace the air, and it did prevent the finish from skinning over, but for some reason, over time the gas disappeared, and the containers that held the finish slowly imploded. I have no idea how this happened, but it did create a partial vacuum and over time, that pulled air into the container, and skinned the finish.
If you use a metal can, the force of the vacuum crushes the can.
Bloxygen did not have this effect, but is about 4 times the price of the dusting stuff.
Thanks TX,
I dont know what bloxygen is; not available here; but from the sound it blocks oxygen and that is what is needed.
Maybe John WW can help you with the dusting spray method.
Many years ago I asked a Sherwin Williams store manager about adding a gas to displace the air in opened cans; he had never heard of such a thing; might have been working commission I think.
Use a propane torch,open the valve a little,the propane displaces the oxygen.
mike
Wow, that's a surprise. Good to know, thanks!My goal is for my work to outlast me. Expect my joinery to get simpler as time goes by.
Deflate an automobile tire, then refill with nitrogen gas. Cobble together a hose adapter to connect the valve on the tire to an air spray nozzle . Spray the nitrogen from the tire into the can. Seal the can. Turn the can over, for storage. The nitrogen will not damage automobile tires.
Thanks AB,
Sounds like an easy solution. Is it really necessary to invert the can if it is full of nitrogen?
Lots of cobbling together in this part of the world; you kinda make do with what you have on hand.
We fill all aircraft tires with nitrogen; compressed air contains some moisture; a friend of corrosion.
Its not necessary to invert the can. But if you don't any skinning that does occur will be on top.
Good point AB,
If the skin is on the bottom it gets into the mix again when you reopen the can and stir.
If the skin is on top you might have a tendency to discard it and this must change the recipe, less liquid, more solids, ergo the color must change???
Probably need a chemist from PP or Glidden to jump in here; did I mention I flunked chemistry??
Once the skin as formed it won't redissolve into the liquid, nor would you want it to since it has already started crosslinking and would just be lumps in the finish. You would want to strain finish you are resurrecting to eliminate such lumps. Varnish almost always needs to be thinned, compared to how it comes from the can, so the relative mix of solids versus solvent is easily adjustable
Some suggest that the remaining liquid may not be as "good as new" and may have trouble curing properly. I would certainly test the drying capabilities before using on an meaningful products. If there is any doubt, better spend a few dollars for fresh varnish than end up with a substandard finish.
Thank you Steve, finishing seems to be a profession unto itself.
I'm still struggling with woodworking.
Propane works well, is low pressure out of the torch nozzle and is heavier than air so it will displace the air in the can.
Thanks dg,
You are the second person to suggest this.
Is there any reaction at all between propane and liquids?
I tried the propane with a quart can of oilbase paint (down about 1/4) and found that it did not work at all. After a week the paint was skinned over at least as badly as if I had done nothing but close the can.
Not to say it can't work, maybe I just didn't get it right.
Thanks TX,
I have never used propane; seems to work for some but not for you.
Nitrogen was my original choice; also I am reluctant to use a flammable gas.
The paint fumes are more flammable than the propane anyway, from what I understand.
I've had good results and no reactions with oil and alcohol based finishes. I have not tried on waterbased finishes so I can't speak to it's effect there.
Thanks dg.
I use mig gas, argon or sometimes argon /co2 mig mix
Since this thread has reopened - it predates me on Knots - I have one other suggestion.You can cascade pressure reducers, so attach another one which will drop the 600psi to 0-50.
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