white patches after polyurethane coat


Awasn

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Hello everyone,

 

I got a secondhand maple wood dining table 4 years ago and decided to re-stain it. This is my first ever job trying to stain wooden furniture. I read a few articles about it on line and talked to guys at Canadian Tier about what all I need to do. This is what I did:

 

1. I started by using furniture stripper to get rid of the old stain.

 

2. Then I used 100 grit sand paper to sand the surface followed by sanding with finer grit paper (180 and finally with 220).

 

3. Then I used Minwax wood finish stain (colonial maple). I applied 3 coats of the stain and everything looked fine and I was happy with my efforts.

 

4. After this i applied a coat of Minwax Fast-drying Polyurethane. As soon as it started to dry, white patches started to appear. 

 

I went back to the store to talk about it and was told that probably since the furniture was old, the wood might have been treated with alcohol or something with might have reacted with the polyurethane to give white patches. So recommended me to talk to some experts who would suggest some other finishing product instead of the polyurethane.

 

Can someone please help me. What should I do. Also please let me know if I followed the right procedure or should I do it differently. Attached is the image of what the white patches look like.

 

Thanks in advance for your help.

post-15993-0-59777000-1407891048_thumb.j

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Wow!  I haven't seen that before..  I sincerely hope this is the only chair you've done so far?

 

I definitely think you'll be sanding this one down again and refinishing it.  Something contaminated the finish but, I'm not too sure about the alcohol.

 

Suggest testing finish in unseen areas (like under the seat) to make sure things are going to work out correctly.

 

There are some great finishing folks here who I'm sure will chime in and give you some great advice!  Good luck!

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Thanks for the replies.

 

The white areas are at the surface and not between the wood and the top coat. After each coat the of the stain it was allowed to dry for atleast a day. And before i put the finish it was dried for a week or so since I did the staining on a weekend and then put on the finish the next weekend.  

 

The weather conditions were hot and not that humid and definitely not raining. 

 

This chair was the worst affected one. On the table it was fine after the first coat of the finish and then I put in another coat and then I could see some patches of white on the table too. However the legs of the table are completely fine without any patches.

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Hi C Shaffer. Yes i did not shake the ply. I mixed it well with a stick. I think the finish is not bad since it worked fine on the legs of the table, which did not show any white patches. 

 

K Cooper - I am not sure if it is water based or not since it does not say anything on the pack. All it says is that it is fast drying clear. 

 

Can anyone suggest some thing else that I can/should use to finish after the stain. Since Its my first ever project so I dont know much about staining and finishing. And since now I will have to start all over again so would be good if some one can suggest something better or different I should use.

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Thanks C. Shaffer,

 

 This was exactly the problem I am facing. So I guess I should strip everything and start all over again. Just had a few more questions if you can answer them:

1. Should I again sand after stripping (progressively form 100 to 120 to 180 grit paper).

2. Does it matter which bran dof the sand paper I use? if yes then which is a good brand to go for.

3. From what I understood from the other post is that the Minwax stain is not a good one. So what kind of stain and finish should I go for. 

4. When I used the Minwax stain it said on the pack that dry it for 15-20 min and then wipe it to remove excess stain. But when I did that it smeared the stain. should I wait for longer before wiping or how is it suppose to be done. 

5. Any other tricks and suggestions for teh job.

 

Thanks once again.

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  • 1 year later...
On 8/13/2014 at 7:52 PM, Awasn said:

Hello everyone,

 

I got a secondhand maple wood dining table 4 years ago and decided to re-stain it. This is my first ever job trying to stain wooden furniture. I read a few articles about it on line and talked to guys at Canadian Tier about what all I need to do. This is what I did:

 

1. I started by using furniture stripper to get rid of the old stain.

 

2. Then I used 100 grit sand paper to sand the surface followed by sanding with finer grit paper (180 and finally with 220).

 

3. Then I used Minwax wood finish stain (colonial maple). I applied 3 coats of the stain and everything looked fine and I was happy with my efforts.

 

4. After this i applied a coat of Minwax Fast-drying Polyurethane. As soon as it started to dry, white patches started to appear. 

 

I went back to the store to talk about it and was told that probably since the furniture was old, the wood might have been treated with alcohol or something with might have reacted with the polyurethane to give white patches. So recommended me to talk to some experts who would suggest some other finishing product instead of the polyurethane.

 

Can someone please help me. What should I do. Also please let me know if I followed the right procedure or should I do it differently. Attached is the image of what the white patches look like.

 

Thanks in advance for your help.

post-15993-0-59777000-1407891048_thumb.j

Hello Awasn, if you do wind up stripping & redoing your project, I recommend using one coat of Zar stain, a good wood sealer (Deft or Valspar) and a Valspar Lacquer finish. 2 coats of  the lacquer should do it but make SURE; the temperature is at least 70° and the humidity is below 70%. (50-60% humidity is preferable) as lacquer will either turn white or orange peel if it is too cold or damp. Hope this helps! 

Edited by finishmikw
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3 minutes ago, finishmikw said:

Hello Awasn, if you do wind up stripping & redoing your project, I recommend using one coat of Zar stain, a good wood sealer (Deft or Valspar) and a Valspar Lacquer finish. 2 coats of  the lacquer should do it but make SURE; the temperature is at least 70° and the humidity is below 70%. (50-60% humidity is preferable) Hope this helps! 

Welcome to the forums but, this post is nearly a year old..

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  • 1 year later...

This same exact thing just happened to me. I've spent forever working on this door and these products just ruined it!! I am so very frustrated right now!

Spent +$200 on new poplar wood, stained it with colonial maple over a week ago applied the polyurethane and all these white areas appeared within minutes. It's a slightly  cloudy day, about 70 degrees, not very humid. Door was clean and dry...

What should I do?

PS I did not shake the varnish, I stirred it very slowly until all the gunk at the bottom mixed in, took like 5 minutes

20170505_144847.jpg

20170505_144906.jpg

20170505_144931.jpg

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On 3/22/2016 at 9:06 PM, TIODS said:

Welcome to the forums but, this post is nearly a year old..

 

On 3/23/2016 at 10:57 AM, AceHoleInOne said:

Maybe in your world. :P Sorta like my wife, she likes to re-hash old stuff that happened in the past.:rolleyes:

 

-Ace- 

 

2 hours ago, BLQQD said:

This same exact thing just happened to me.

There see?  Archival threads have ongoing usefulness :D.

@BLQQD, Is that a waterborne poly over an oil stain?

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