stain and epoxy

[olandrea]

Hi to all,
I would like to know what stain works with what kind of epoxy brand. I think water basted stain is not the best for outdoor use. It will not hold the color very long. Oil stain hold the color but is not the best with epoxy. And because you can stain a boot that will be covered with epoxy only ones ( cold molded build) you have to use the best stain you can get. I know that West makes some test with different stains , but I would like to know your long term experiences with stains and epoxies.
Thanks Olaf

[Todd Bradshaw]

Either alcohol or water-based stains work well with epoxy and don't interfere with the bond the way oil stain will. Assuming that your epoxy coating is properly protected from UV, I don't think you'll have much problem with the stain fading, though It's probably not the best finish to leave out in the weather uncovered for long periods of time. This one was alcohol-based stain and WEST epoxy and sat outside under a Sunbrella cover for the five years I owned it after completing the work on it and it showed no signs of fading.

http://webpages.charter.net/tbradshaw/Sail%20photos/star.jpg

[Canoez]

Nick Schade had used aniline dye on his kayak. I've got written down somewhere whether it was alcohol based or water based. He seemed convinced that one was better than the other. Someone else I met went exactly the other way. :rolleyes:

Personally, I think that's hogwash. They're both the same pigments and as long as you have epoxy and/or a UV filtering varnish, I think it would be fine.

[olandrea]

I found a two part polyurethane wood stain for boats suitable to be overcoated with one and two components products. This should work with eboxy. Riva uesed Stoppani products for there boat.
http://www.woodenclassics.com/pages/webshop_detail.php?id=2610 (http://www.woodenclassics.com/pages/webshop_detail.php?id=2610)

Interlux Interstain an Sandusky paste wood filler and stain fills grain while staining wood is maybe also not a good idea under epoxy?

Todd what do you use for epoxy UV protection?
Thanks Olaf

[Todd Bradshaw]

The Star was an interesting project. It was built in 1960 from edge-glued (some sort of tongue and groove joint) cedar planking about 5/8"-3/4" thick and painted white with enamel when I got it. This worked, but the cedar was constantly checking and making small splits in the paint. I ground it down to bare wood with a big disk sander and then covered the hull with 3/32" sliced mahogany veneer set in WEST 105/205 epoxy. I used a Bostitch T-11 "Tackler" staple gun to hold the veneer down tightly until the epoxy set. This gun shoots round-legged staples that are about the size of office staples only they're slightly longer. Once you pull them out, the holes are so small that they virtually disappear into the grain. Once hardened, the surface was sanded again using the big disk grinder and 100 grit paper glued to a feathering disk (8" diameter with a soft foam pad) to remove any irregularity and any resin from the surface of the mahogany.

I bought two paper bags of stain powder, one brown mahogany and one red mahogany from an old-time paint store in town and a gallon of alcohol and started playing with scrap wood and mixing the two pigments until I got a color that I liked. The stain was applied with a 4" brush, brushing with the grain and immediately wiping it down, also with the grain. By immediately, I mean that you have the brush in one hand and the wiping rag in the other as you only have about 20 seconds to move the stuff around before it dries. Everything on this boat (stain, epoxy and varnish work)was done by starting at the bow stem on one side and working all the way around the boat in one shot with no stopping and no help. The second coat of stain was applied the same way, but you have to be a bit careful about keeping the color even as it will disolve the first coat to some extent. I did find that after the stain dried, you could rub it down with a dry cloth and even out the color a bit.

Top-coating was done with six coats of WEST 105/207 clear-finish epoxy, rolled and tipped and then sanded smooth with the feathering disk. Captain's Varnish was used for the final layers and UV barrier. It was also rolled and tipped. I built a full Sunbrella cover for the boat, but it lived outside all year long. About five years later I moved here and had to peel off the old registration numbers and apply new ones. There was no shadow at all visible where the old numbers had been, so I guess it didn't fade.

The alcohol stain was gorgeous and had fantastic shimmer in the sun. We've since used a lot of water-based stain on floors, baseboards and door frames in our house. It has a bit longer working time than the alcohol stain, but is a little muddier (less transparent) than either oil stain or alcohol stain.

[Canoez]

The alcohol stain was gorgeous and had fantastic shimmer in the sun. We've since used a lot of water-based stain on floors, baseboards and door frames in our house. It has a bit longer working time than the alcohol stain, but is a little muddier (less transparent) than either oil stain or alcohol stain.

"Muddier" How did you prepare the water based stuff?

[DavidS]

I would be interested to hear if anyone has any experience using Minwax gel stain and then covering w/ epoxy. As Olaf said, the West guys did some experiments w/ epoxy over stains and their conclusion was that West epoxy worked OK over the gel stain (gel stain allowed to dry for 1 day). However, I am curious about how this would hold up over a longer period of time, weather, etc.

Thanks,
Dave

[Wild Wassa]

If permanence is important, I'd avoid aniline dyes/stains because they’re organic based. Organic pigments (called fugitive pigments) have low levels of permanence ... for exterior use they should be avoided. For interior use it is not really an issue, although organic pigments will change slowly ... even in the dark, dark fading.

I personally would avoid aniline pigments, if I knew they were in the stain. I make my own stains so I know what to expect.

What is best, are the rare earth or mineral pigments, in stains for exterior coats, UV stabilizing will help the longevity of a pigment, from changing rapidly. Organic pigments with their low levels of permanence, no amount of UV stabilizing really helps.

Pigments used in stains must be transparent or semi-transparent when they are in the binder, otherwise the stain will look muddy ... asking a shop assistant about the stain will usually bring a totally blank look, ask the oldest guy at a specialty store for woodworkers if you need real answers concerning the stains and he will probably say to you that he still makes his own.

I also use concentrated tints in epoxy (with non yellowing hardeners) for making stains, the tints used for tinting flowcoats, I find are excellent. They tend to be transparent and semi-transparent (even the white tints are semi transparent, sadly). I think epoxy tinted and then wiped off with a rag can give an excellent natural looking hue. You can blend the hues, balance the values put as many thin coats on as you need. Then apply normal epoxy if needed (again) using a non yellowing hardener.

I use Class 4-5 and 6 transparent and semi-transparent pigments in clear polyurethane, many are titanium based ... when I'm being really serious about colouring up a job, that is.

The way you learn is to experiment, with the pigments and binders ... all proprietary stains look false on timber. Once you know what you like, you will wonder why you ever bought a proprietary stain 'a one wash wonder' ... when you look into timber and see that the colour is additively built.

When I look at stains called 'Rosewood' or 'Redwood' or whatever ... I think who are these manufacturers actually trying to kid ... and then Blind Freddy walks into the store ... "Umm, I umm want umm, Claret Ashe." Claret Ashe, it is our most popular stain Sir. Step right this way !!! ... DING! DING! DING! WE HAVE A WINNER !!!

Warren.

[Todd Bradshaw]

"Muddier" How did you prepare the water based stuff?

Not sure what you're getting at here.....We prepared the water-based stain by opening the can, and stirring it, following the directions on the can. It was applied over freshly sanded, raw oak, either with or without using Minwax pre-stain first (which seems to make it brush out a bit more evenly). The brands we used were Minwax and Flecto Varathane. It's nice stuff and not bad to work with once you understand that you don't have the kind of rub-out working time that you're used to with oil stain, but in terms of being transparent, it isn't even close to the alcohol-based stain and it's somewhat more opaque than a similar shade of oil stain. We do this stuff in the winter when I have more free time, so water-based stain and varnish allow us to do the jobs without filling the house up with solvent fumes. On my floors and baseboards, it's fine. On a boat, I'm not absolutely sure I would be happy with it.

http://webpages.charter.net/tbradshaw/Sail%20photos/corner%20detail%202%20copy.jpg

I suspect that some of the metallic dyes that the luthier supply places sell would work for tinting resin as they have a wide range of finishes that they are compatible with and many are light-stable. I used this stuff on the back and sides of this mandolin body and it had excellent transparency. It was an expensive little bottle of stuff, but it literally took only a few drops to tint a spray gun full of varnish. The top, by the way, is veneered with some nice maple I found at Woodcraft, applied with and overcoated with WEST Epoxy before final varnishing (once a boatbuilder, always a boatbuilder).

http://webpages.charter.net/tbradshaw/Music%20stuff/Guitar%20Rebuilding/mando%20body%20copy.jpg

Tints:
http://www.stewmac.com/shop/Finishing_supplies/Colors,_tints,_and_stains/ColorTone_Concentrated_Liquid_Stains.html

[Canoez]

"Muddier" How did you prepare the water based stuff?

Not sure what you're getting at here.....We prepared the water-based stain by opening the can, and stirring it, following the directions on the can. It was applied over freshly sanded, raw oak, either with or without using Minwax pre-stain first (which seems to make it brush out a bit more evenly). The brands we used were Minwax and Flecto Varathane. It's nice stuff and not bad to work with once you understand that you don't have the kind of rub-out working time that you're used to with oil stain, but in terms of being transparent, it isn't even close to the alcohol-based stain and it's somewhat more opaque than a similar shade of oil stain. We do this stuff in the winter when I have more free time, so water-based stain and varnish allow us to do the jobs without filling the house up with solvent fumes. On my floors and baseboards, it's fine. On a boat, I'm not absolutely sure I would be happy with it.

I suspect that some of the metallic dyes that the luthier supply places sell would work for tinting resin as they have a wide range of finishes that they are compatible with and many are light-stable. I used this stuff on the back and sides of this mandolin body and it had excellent transparency. It was an expensive little bottle of stuff, but it literally took only a few drops to tint a spray gun full of varnish. The top, by the way, is veneered with some nice maple I found at Woodcraft, applied with and overcoated with WEST Epoxy before final varnishing (once a boatbuilder, always a boatbuilder).

Tints:
http://www.stewmac.com/shop/Finishing_supplies/Colors,_tints,_and_stains/ColorTone_Concentrated_Liquid_Stains.html

Well, as both you and Warren have noted, there are other choices than analine dyes. I use analine dyes when I make furniture. I then overcoat with a wash of shellac (50/50 mixture of denatured alcohol and shellac - either 3lb orange or blonde, depending on the project), and then do a hand-rubbed oil (Minwax Antique Oil or Linseed/Turps) with a final coat of wax.

At any rate. I've had problems with muddy dye, too. The biggest solution I've found was not to use tap water, but to buy distilled water, boil it and dissolve the dye after it has cooled a bit. I usually use more water than is called for because the dyes don't fully dissolve in the amount of water called for by the manufacturer. Both tap water and the recommended concentration seemed to result in "muddiness".

Warren is right, IMHO, as you need to experiment. I'm trying water-based anilines under epoxy for my boats now. However, they aren't stored outside, so fading probably isn't as big an issue for me as for someone who stores a boat outside. I always figure if enough UV is getting though my varnish to cause my dye to fade, I've got worse problems with the epoxy coating the dye.

Beautiful guitar body, BTW.

[Todd Bradshaw]

"I always figure if enough UV is getting though my varnish to cause my dye to fade, I've got worse problems with the epoxy coating the dye."

That's pretty much what I thought on the Star but I was pleasantly surprised later on when I peeled off the registration numbers and they hadn't left any shadows in the stain (I had already pretty much planned on having to figure out some kind of cover-up). It was my first experience with alcohol stain and I have no clue what kind it was. The old paint store had a couple big metal cans full of the stuff which looked like they were left over from the 1950's and they just scooped some into a paper bag and sold it by the pound. Lucky for me, (sheer dumb luck) it was light-fast. I also used it on the 18' Simmons Skiff that I rebuilt, since the motor well, the deck, the console and a few other parts were all new 3/4" Bruynzeel ply had at least some areas that were epoxy-coated before being bright finished. The stain lasted longer than the boat did (a pier on Lake Michigan collapsed onto it during a storm a couple years later while the owner was there on vacation. Smashed it to bits....bummer).

The mandolin cosmetics were kind of a fluke. It was a cheap Saga kit off of eBay that I said I'd assemble for my brother while I was building a new body for one of my basses. I was spraying water-based laquer in my unheated garage in February at 37 degrees. It was epoxy-coated after veneering and the back and sides were to be that rusty brown color, so I started spraying the color coats. I had a really lovely matching sunburst going on the top and at the last moment, the gun spit out a little droplet, making a little brown spot right in the middle. I played around for about three days, trying to either remove it or justify it and finally gave up and got out the random orbit. The plan was to take the top back down to clear epoxy and re-spray the burst. Once I got the top clean though, we kind of liked that country-western-saddle-shoe look and ditched the burst idea. It ended up just getting 14 more coats of clear laquer, followed by hand sanding and polishing. As I remember, the kit was only about $125 and it's not half-bad in the hands of somebody who can actually play mandolin (which certainly does not include me).

http://webpages.charter.net/tbradshaw/Music%20stuff/Guitar%20Rebuilding/mand%200x5%20copy.jpg

[olandrea]

W.D. Lockwood is procucing stain since 1895. They say that there water stains have the most fastness to light even more than there alcohol and oil stains.
Lockwood Water Soluble Powders

Excellent for deep penetration, fastness to light, and use under lacquer. They are suitable for any wood and most superior in results on hard, close grained woods, like maple, birch, etc. Any finishing material may be applied over them, as the color remains clear and free from smears under lacquer, shellac or varnish. Their great penetrating properties bring out beautiful contrasting grain effects between the soft and hard parts of the wood. Shaded and two-toned effects are obtained by varying the strength of the stain solution, by applying two coats of stain, or by manipulation of the spray gun.

Lockwood Alcohol Soluble Stains
Excellent for refinishing or repairing all woods; for coloring sap streaks and on work where the stain must dry instantly. They may be finished with varnish, shellac, lacquer, wax or oil, but reflect a different shade under each material, owing to the varying action of alcohol, oil, etc., on the soluble properties of the stain. These stains are about equal to the oil stains in fastness to light, but not as permanent as LOCKWOOD WATER STAIN POWDERS. They are useful for tinting shellac or lacquer.

http://www.wdlockwood.com/main.html

I don't know if they using aniline or mineral pigments?
Olaf

[Canoez]

Someone correct me if I'm wrong, but I had always thought that "soluble"
indicates aniline pigment, not mineral.

DavidS - Personally, I try to avoid anything with oils under epoxy. The gel stains form Minwasx are oil based. That being said, if the folks from West System have used the stuff successfully under their epoxy (and you plan to use their epoxy) give them a call and ask about it. They do extensive testing with their resins and should be able to give you good guidance.

[pipefitter]

Wonder if one could make a stain with a CPES type epoxy sealer? It seems that it should have good suspension qualities and enough of a binder with the trace epoxy and enough solvent for solubility.

[olandrea]

The Lookwood water stain is made from Acid dyes and Natural Dyes.
Olaf

[DavidS]

Regarding the Minwax gel stain, I called West System yesterday and talked to a couple of their guys. One of them was the author of the original article from West on epoxy adhesion to various stains. Unfortunately, they did not have any additional results or anything based on long-term adhesion results. They did say that they didn't believe that it would be an issue given that their original testing showed that the adhesion to the stained wood was acceptable as long as the stain was allowed to dry sufficiently.

I would still be interested to know if anyone has done any long-term testing.

Thanks,
Dave

[Eric D]

From a strictly woodworking basis, not a boat which is going into the water...

the pros all state that it does NOT matter if the dye is water base or oil base. once either are PROPERLY DRIED completely, you can use water over oil, or oil over water based products with NO ILL EFFECTS.

Same is true of painting oil over water based primers. Key here is complete drying.

So, by theory, epoxy should be NO different. YMMV.

[DavidS]

Eric,

In theory I would agree, and that seems to line up with what West told me. As long as the stain (gel stain is oil based) is allowed to dry completely (1 to 4 days in their test) then the epoxy did adhere. I don't know if sunlight or other environmental factors would change that over time.

Thanks,
Dave

[Todd Bradshaw]

"Same is true of painting oil over water based primers. Key here is complete drying."

I wish my floor knew that. They're oak with water-based stain and varnish. After a couple of years I decided to give them another coat, so we cleaned them and Scotchbrighted the old varnish. I accidentally grabbed the wrong can off the shelf and put on a fresh coat of oil-based varnish by mistake on one section. It happens to be where I work and every time I tape out a sail plan with masking tape and later remove it, it very neatly takes the top layer off.

[Canoez]

One of the guys in my cedar-strip class had taken his boat home to work on it. He was fairing and sanding and took some mineral spirits to look for glue spots on the hull before glassing. There were many warm days before he brought it in and (Mineral spirits unknown to me) we applied an epoxy sealer coat and then glassed the hull using System 3's regular resin.

Later on, he approached me about the delamination that was happening. After some discussion, I found out about the mineral spirits. His is the only boat I've ever seen this delamination problem with and I've been around for a few.

Based on this experience, I would NOT apply oil based stains or mineral spirits/thinner to a wood surface before using epoxy.

[olandrea]

Canoez, maybe there was some thing else in the mineral spirits. A lot of builders using alcohol stain and have no problems. Alcohol - mineral spirits I think there is not much differents.

Here is what happen to Mark Bronkalla:

Staining
I applied Min-Wax pre-stain conditioner and Red Mahogany stain. This gives a very even coloring. The water based filler soaked up excessive stain and is now too dark. The epoxy filler is a good to excellent match.

Water based stain is too hard to handle so I went with oil based. The Min-Wax stain is non-filling.

I pre-tested the stain to epoxy adhesion with wood test pieces as instructed by Gougeon Bro's. Adhesion is GREATLY improved by sanding with 220 grit after staining. Be sure to allow plenty of time for the stain to dry. A week is recommended.
Later, when trimming the edges, the fiberglass started to lift. There may be trouble using the stain.
Since I did my boat, Gougeon Brothers have run some tests (Summer 2003) with a number of stains and the MinWax stains came out with poor adhesion results.
A few other builders have tried the Behlen Solar Lux dye stains with excellent results. Just remember with a dye it will look pretty awful as it first dries. DO NOT fool around with it at this point!!!! It will even out in color and transparency as the epoxy is applied. Practice on some good sized samples to get your courage up. The dye stains are not as colorfast as the oil based pigment stains, but are much more transparent and show off the light refraction by the wood fibers (chatoyance). This gives a much "livelier" looking finish.

[Todd Bradshaw]

"Alcohol - mineral spirits I think there is not much differents"

- Alcohol and mineral spirits are drastically different - as are the stains produced from them. The fact that one may work has nothing to do with how the other will work.

"DO NOT fool around with it at this point!!!! It will even out in color and transparency as the epoxy is applied."

- This is pretty risky. Putting epoxy resin over something that you're not sure looks the way you want it to look is a good way to permanently seal it in all it's ugly glory.

I agree with Canoez. The more you learn about working with epoxy the more careful you get about things like solvent contamination. The alcohol in alcohol stain flashes off in a matter of seconds and within a day or two, you can be sure that the surface is bone dry with no remaining alcohol. Oil takes a long time to dry and a portion of it remains in the wood, which is not a good thing when you're preparing to epoxy coat it. If I was doing this job, I'd be far more worried about screwing up my epoxy bond with oil than I would be about the possibility of alcohol or water-based stain fading. Both of these stains have an established record of working. Oil stain is a much higher risk.

[DavidS]

Just to be clear, the Minwax stain is oil based and failed the West System testing. However, the Minwax Gel stain passed the test even though it is also reportedly oil based.

See: http://www.westsystem.com/ewmag/21/epoxy_adhesion.html

Regarding the mineral spirits, I'm surprised that that would cause a problem provided that it was completely dried. When using epoxy on oily woods (e.g. teak) they recommend wiping the wood with acetone to break down the oils. Allow the acetone to evaporate before applying epoxy.

Dave

[Canoez]

Folks, I think what Todd and I have been trying to say is that it is an issue of volatility. The alcohol and water "flash off" in a relatively short time without residue. Petroleum based stuff doesn't flash off quickly and leaves some of the "heavier" distillates from the process behind. Contamination of your bonding surface is a bad deal.

David, on the teak, the acetone is used to strip away the wood's natural oils before bonding or sealing.

As my father once told me, "I can't make you listen to what I tell you, but you may wish you did."

[DavidS]

Yes, I agree. What surprised me from the earlier post was that mineral spirits would cause the problem while acetone wouldn't (and acetone is actually used to solve a similar problem with oils on the surface).

It's been a while since I took chemistry but from what I've just Googled, it seems that mineral spirits are also petroleum based. Maybe that's the reason for the problem.

Thanks,
Dave