[cjaustin81]

Last September I had a cedar post installed on my front porch , I'm just now getting ready to paint it. I went to look at the post today and noticed in 10 spots where nail holes were, there's tannin bleed.

How should I fix this before I paint? I read someplace that you can countersink the nails, then swab water repellent over the nail holes, followed by wood filler. I also read you can use oxalic acid or oxalic-based solution to remove the stains.

Aside from re-doing the whole base, what are my options? Will this tannin bleed come back if I use a quality oil-based primer (Fresh Start by Benjamin Moore for example)?

 

[cjaustin81]

I called the Benjamin Moore store by me and they recommended to sand the areas of the
stain down a little bit (even though it's rough cedar). Then after I sand it to use a wood filler (MHC spackle he said) followed by spot priming it 2-3 times in those areas. He said just regular BM Oil-Based Fresh Start would be good.

I saw that BM makes a product called Fresh Start Tannin Stain blocker 040, has anyone used that? I asked the guy and he said I didn't need it.. but I'm now wondering since it's made to cover tannin stains.

 

[Gymschu]

http://www.sherwin-williams.com/hom...ver/dirt-stain-discoloration/tannin-staining/

 

[PRP]

Looks more like iron stains than tannin since it's only around the nails. In the future always use stainless fasteners on cedar.

I'd just spot prime them a day before priming the whole column. Since its been exposed since September sand it before primer.

 

[cjaustin81]

Looks more like iron stains than tannin since it's only around the nails. In the future always use stainless fasteners on cedar.

I'd just spot prime them a day before priming the whole column. Since its been exposed since September sand it before primer.

It's rough cedar, which is why I wasn't originally going to sand it. What grit would you use? I may sand it if it will remove the bleed easier I just will need to sand the entire post to make it even.

I thought the iron caused the tannin bleed? It's weird because only some of the nails have the bleed, not all.

 

[cjaustin81]

http://www.sherwin-williams.com/hom...ver/dirt-stain-discoloration/tannin-staining/

Thanks, I read that article before and was considering using the Sherwin-Willams SuperDeck revive to clean the tannin, followed by an oil-based primer. It seems in line with what the paint store said. The only thing missing in that article is to use a swab of water repellent on the nail heads followed by a wood filler before priming.

 

[PRP]

It's rough cedar, which is why I wasn't originally going to sand it. What grit would you use? I may sand it if it will remove the bleed easier I just will need to sand the entire post to make it even.

I thought the iron caused the tannin bleed? It's weird because only some of the nails have the bleed, not all.

I'm not talking about sanding it smooth. Just to remove any weathered wood. Even if it doesn't look like it, wood will weather rather quickly once installed. I would do a light hand sand with the grain with 80 grit. It'll take less than 2 minutes.

Yes, it is a form of tannin bleed. It's because of the zinc reacting with the cedar. Always refered to that type as iron stains and the other as bleed. Bleed can also happen from moisture and looks brownish when it shows through paint.

Ben Moore 094 is our go to for cedar.

 

[cjaustin81]

I'm not talking about sanding it smooth. Just to remove any weathered wood. Even if it doesn't look like it, wood will weather rather quickly once installed. I would do a light hand sand with the grain with 80 grit. It'll take less than 2 minutes.

Yes, it is a form of tannin bleed. It's because of the zinc reacting with the cedar. Always refered to that type as iron stains and the other as bleed. Bleed can also happen from moisture and looks brownish when it shows through paint.

Ben Moore 094 is our go to for cedar.

I saw they have the alkyd primer (094). I wonder how much of a difference that would make versus the Fresh Start oil-based exterior primer?

I can pickup some of the 094 if it will be a better primer to use on this application.

Another question I have is how best to treat the nails? I was thinking of dabbing the nail holes with water repellent followed by a wood filler. Do you guys think this step is necessary?

 

[Gymschu]

The water repellant is worth a shot. Hopefully it doesn't repel the wood filler which sometimes happens with water repellant. It creates such a seal that anything with water in its' chemistry doesn't stick. It's unfortunate about the nails. Nails in any type of substrate, often act like wicks. In this case it's just worse because of the reaction with the cedar. Doing what you are doing has to help, but, I'm guessing that in a few years those stains will reappear due to the wicking action of the nails, although the stains won't be quite as prominent.

 

[ToolSeeker]

As stated that's not tannin bleed that's from the fasteners. To sand any will look smoother than the surrounding areas and be quite noticeable. The fasteners heads need to be sealed then use the cover stain.

 

[cjaustin81]

As stated that's not tannin bleed that's from the fasteners. To sand any will look smoother than the surrounding areas and be quite noticeable. The fasteners heads need to be sealed then use the cover stain.

what type of sealer or water repellent would you suggest?

 

[mathmonger]

Even if it doesn't look like it, wood will weather rather quickly once installed.

Yet if you put in a new deck, you're supposed to let it weather before you stain it. Can anybody make sense of that?

 

[PRP]

Yet if you put in a new deck, you're supposed to let it weather before you stain it. Can anybody make sense of that?

With PT decking it has to dry and it also has mill glaze which can prevent the stain from absorbing. Brightener can be used to break the mill glaze but we find sanding to be superior.

 

[mathmonger]

With PT decking it has to dry and it also has mill glaze which can prevent the stain from absorbing. Brightener can be used to break the mill glaze but we find sanding to be superior.

So it depends on the type of wood. The cedar doesn't have to dry out. You want to remove the mill glaze and get that coated ASAP.

 

[ToolSeeker]

So it depends on the type of wood. The cedar doesn't have to dry out. You want to remove the mill glaze and get that coated ASAP.

If it's rough cut cedar it shouldn't have mill glaze.

 

[cjaustin81]

I appreciate all the help. I believe cedar needs to be less than 15% moisture content before staining/painting. This wood has dried for at least 8 months.

After going to the paint store this is how I plan to tackle the job:

1) remove the old tower caulk (accelerator).
2) clean tannin with Max-Prep Wood Restore using bristle brush.
3) trim and recess any exposed nails.
4) fill nail depressions using MH Patch Ready (supposed to be VERY durable).
5) Prime with BM Exterior Wood 094 (specifically for cedar, bleeding.. thanks to the gentleman that recommended it.. the paint store didn't even know about it until I gave the 094 code).
6) after I prime I'll then use the Tower Tech Caulk (very flexible, durable).
7) 2 topcoats.

I'll post a pic and let you guys know how it turns out when I'm done.

 

[cjaustin81]

UPDATE

I removed the tannin using the deck rejuvenator. I then filled all the nail holes w MH Patch, followed by tower tech 2 caulk. I then applied two coats of BM 094 cedar primer, followed by 2 topcoats of BM Aura.

I'm happy w the results! Thanks for the help.