My Poly Freaken Pealed Off!!

[stoutman]

I made a maple table a while back and I finished it with Trans Tint dye stain (liquid water based). I diluted the dye with isopropyl alcohol per the instructions on the container. I applied the stain with a rag and let dry about 30 minutes or so. I next applied my polyurethane sealer coat (50:50 poly:mineral spirits) followed by several more coats with 24 hours in between coats.

The finish has cured for 3 weeks now and the table was being used. I noticed a small discoloration in the center of the table tonight which I thought was dried milk. (my son who is 1.5 years old had his milk cup on it earlier today) I scratched what I thought was milk with my finger nail from the surface of the table, but it wasn't dried milk. The discoloration was actually a section of poly that had lifted from the surface of the table. When I scratched it with my finger nail, it spread into a MUCH larger area. I cant tell for sure but I think it went down to bare wood (not just an outer layer pealing off).

I need to resand the entire top and restain. And refinish with poly. What a big f---en pain in the a--.

Why did this happen? I think it may have to do with not letting the stain dry (alcohol) enough before applying the poly, but I'm not sure. You can put an oil based poly over a water based stain, right?

I think I have had it with poly. I am either thinking about giving the poly (minwax) one more try or I am gonna apply lacquer (Deft brush on) on the top.

[Mike Hide]

I don't think a water stain under poly should make any difference so long as it is absolutely dry. the alcohol should quicken drying but I think you should leave it at last overnight in a dry warm environment.

Read the instructions on the dye you are using to make sure even when dry that there is nothing in the colorant that could react with the finish.....mjh

[BruceR]

I agree, 30 minutes is way too short of time. I've put lots of poly (oil and WB) over water soluble dyes without events, but I've always allowed a day or two to dry.

-Bruce

[Ron Magen]

Or try 'compatible' materials.

'Water spray, dry, & sand' process to raise & remove 'fuzz' - - 'Water Based' die defused in water - - 24-hour dry 'Water Based' poly - - one coat - - let dry at least 2-3 hours - - lightly sand to remove any remaining 'fuzz' and give 'tooth' for next coat 'Water Based' poly - - as many coats as you like{for me, this is typically

6}, 24-hours apart, lightly sanding with finer & finer grits between. This gives a very hard, abrasion resistant finish for anything that will be a 'working' surface. {as opposed to purely decorative}

Regards & Good Luck, Ron Magen Backyard Boatshop

SNIP

The discoloration wasactually a section of poly that had lifted from the surface of the table.

[Mike G]

Well, I can think of several possible reasons for the failure, but, with your vast year and a half of experience I'm sure you know them all.

[stoutman]

Ah come on Mike. Are you still mad at me? Ok, everything you said was right and I apologize. Can we be friends?

I am still a little confused though about your 3D grain, but like you said, I only have 1.5 years experience. Maybe in a few years my grain will appear

3-D. Can you offer any advise on this matter? Do you give seminars on finishing?

:)

[Bay Area Dave]

and those possible reasons are?

dave

Mike G wrote:

[stoutman]

Dave,

Mike is mad at me and just want to taunt me with is extensive knowledge on refinishing. Granted, he has more experience than me, and probably knows more than me about woodworking and finishing, as do most people on this NG, but I think he is a little nutty. :)

Do most people hate finishing? I love woodworking, but HATE finishing more and more with every project. Does it get easier? Will I grow to love it?

[Young_carpenter]

I can think of one big reason Ok two The dye wasn't long enough to sit and dry. (at least 4 hours would help) An you didn't mention sanding between Poly coats. 24 hours is a long time in the poly realm to recoat and not sand. 4-6 hours might be ok but not 24, especially since at 50:50 the drying/curing time for poly goes down considerably (experience talking here).

[Mike G]

First thing to do is to take a look at the packages of your sandpaper.and check to see if it says stearted or some derivitated there of anywhere on it.

Steartes on the sandpaper or in sanding sealrs are metallic soaps added to make sanding easier by acting as a lubricant to keep the paper from clogging.

The down side is that it can give you adhesion problems. In general sanding sealer and stearated sandpaper are best avoided. If the sandpaper getting gummed up is a problem it's better to use and open coat paper or more sandpaper..

It isn't absoutly necessary to sand a varnish if you are recoating in less then 24 hours but it doesn't hurt. After 24 hours it is necessary to provide some tooth so the next coat of varnish can mechanically bond to the previous coat. Unlike shellac and lacquer varnish doesn't bun in to previous coats.

However long you waited between coats I'll assume you sanded then wiped down the surface. What did you use to wipe down after sanding? That would be another place to look for this type of problem. My preference is to vac the surface rather then taking a chance on leaving any residuales on it. I'd have to also ask to what grit you sanded between coats. Hopefull not a real high grit. 220 is usually sufficiant, get much higher then that and you aren't leaving a lot of tooth. Think sanding maple to, say, 600 grit and trying to stain it with a pigment stain. It's be like trying to stain steel. There are insufficient places for the pigment to gather and get bonded.l

Temperature and thickness of coats can have a lot to do on the curing of a finish. The principal ingrediant of an oil varnish is tung oil (hopefully). The thicker the coat/coats the longer it takes to cure properly. Bury a thick coat under three or four more thick coats and your grandkids may be waiting for the finish to completly cure.The same if the temperature is too low. My opinion, thin coats are better and I'll generally leave the shop thermostat turned up overnight if I am waiting on an oil to cure.

As a side note, I've heard it said that some of the "Old Masters" paintings still haven't dried completly

There is a start anyway. The solution may not be there but it is my list of "The usual suspects".

As to the 3D effect. Possibly I caused some confusion. The term most heard here on the rec is poping the grain. If you happen to have some nicely figured wood scrap around give it a coat of tung oil, let it dry, spring for a spray can of lacqer and apply four or five coats then rub it out, removing the surface gloss, (couldn't help myself there) and get a deep sheen. After it has been rubbed out hold it up and move it around under a glancing light. Do it right and the grain of the wood will actually look like it has a depth of it's own ie 3D.

[Jim_Milner]

Just a 'little' nutty?

[stoutman]

I sanded it between coats with 320 grit lightly. This is the third time I have tried to finish this piece. The first time I used wipe-on poly all over the table. On the top I had 4-5 coats. I rubbed out the top with 4F pumice and cut through. I had to resand and restain the top. But I didn't wipe the poly on again (never again on a top!). I foam brushed it on and used a higher ratio of poly to mineral spirits.

I think next time I am gonna try Deft brush on lacquer. The guy at woodcraft raves about it. Anyone have any with this stuff?

[Mike Hide]

One thing I should add, first of all in most cases water based stains are supposidly the best because they penetrate deeper. On the other hand they invariably raise the grain which is a pain in the a..... There are two solutions use a good non grain raising [NGR] stain or secondly raise the grain before staining . To do the latter after final sanding [incidentally I have been finishing for over 30 years and have never had any problem with sterated papers] wet the surface with a dilute glue water solution ,let dry and resand . I used to do this three times , the glue part when it dries will generall hold the "whiskers" out so they sand off easier. If you do this then it should almost eliminate the need to sand the finishing coat bar the need togive the susequent coat a "key" and to eliminate any knobs that got into the existing finish coat while it was still wet.

One you move to stains other than water based [NGR] try and get one that has no pigment , that just colors the wood. then the grain will really "pop" as there is now nothing to obscure it .....mjh

[Lawrence L'Hote]

-----lots of snippage above----------- FWIW, when I use the water based dyes I always wait overnight for it to dry then hit the high spots very lightly with a 3M 220 sanding sponge to get rid of those wood wiskers. Then I lay on a light coat of 1 lb shellac, let that dry and sand lightly with the sponge. Then I apply thinned poly(with HVLP) sanding lightly between coats. IIWY I would toss that can of poly and get another brand or a fresh can of the same.

Larry

[stoutman]

Thanks for the advice. I just wish I had a HVLP equipment. I gotta elbow grease all my finishes on. :(

Will the shellac hold the poly to the surface of the better?

The poly is new. I got a small can just for this project.(minwax).

I think my poly days are over for now. I'm gonna try something different next time. I have no spray equipment though. Maybe brush on lacquer next time.

[Bay Area Dave]

Hopefully, he'll get over it and start giving some WW advice. I'm watching my p's and q's to avoid as many rancorous replies as I can! :)

dave

stoutman wrote:

[Bay Area Dave]

The best choice for sanding between coasts of finish Superior performance for a premium surface finish Won't clog, tear or transfer color

Maybe you should call them up and ask them politely if they know what they are doing.

dave

Mike G wrote:

[Bay Area Dave]

I used Deft many years ago and hated it due to the fumes. I applied it outside and still got zonked by it. I used it on an unfinished stereo cabinet and stuck my head into the interior while brushing it on. It clears the sinuses and rots the brain. It's a concoction of lacquer and other junk to allow it to be brushed on. "Nasty" doesn't do it justice. Wear a respirator if you choose to use it.

dave

stoutman wrote:

[Bay Area Dave]

I shared somewhat the same frustrations in not having an HVLP. I couldn't see spending a grand, "just to do finishing". Finally I realized there's no decent alternative, so I bit the bullet and got an Accuspray HVLP. Using it is remarkably satisfying, if somewhat expensive. Think long and hard about "making do" without one.

dave

stoutman wrote:

[Leon]

I am chiming in here way late and the advise given is good. BUT... you mentioned that you hate finishing and you also mentioned that you used Miniwax.... I have been doing this for 20+ years and hate Minwax products... I do not hate finishing....

May I suggest General Finishes, Bartleys and or Zar? You will probably not find them in the typical home center or hardware store. Check out the woodworking stored like Wood Craft.