Here is a picture of what the black spots look like

http://i1159.photobucket.com/albums/p638/marcus410/photo.jpg

Here is a link that might be useful:

I would use a stain stripper followed by a wood brightener. This should "deep" clean a little better. Are you scrubbing or lightly pressure washing when you tried the EFC-38?

yes. scrubbing with a brush and then also rinsing lightly with a pressure washer.

I would use the HD80 followed by the Citralic. Both are made by woodrich. This should prep much better.

Marcus:
Please post after photos and info. Are you going to stain over the gray? I'll be following your thread...

I have a grill island that I built the same summer as the deck and it fared much better being that it only has vertical surfaces. The top is Granite. I used the restore a deck cleaner and brightner on it and then restained with TWP. It came out great. Just as good as it looked the first time I stained it. I did do a little light sanding just to smooth up a few spots. So I am hopping that the MD80 will remove the black spots on my deck. If it does I will be good to go. I will post some pics of the grill island tomorrow.

Marcus,

Did you get some brightener to neutralize the HD80? It is very important to do this. Stains will perform better when the wood's pH is neutral. Failure to do so will leave the wood highly caustic resulting in faster stain failure.

Yes. I bought the step 2 brightner as well. Just thought was a given so I didnt mention. Thanks for checking.

DD2 is VERY correct on the Neutralizing issue(s) here.

Without THAT step, people think..."as long as the stain/color is gone, I'm OK...", when in fact they're creating another problem by NOT doing it!!

Also...watch your dry-time.
Check with a moisture-tester!!
It's the ONLY sure way to quantify it.

Faron

EF 38 is a percarb and not a stripper. You need to use DD's HD 80 followed by a neutralizer (oxalic or other "acid) then let dry to 12% moisture and then seal. I would use Ready Seal.

Here are some pictures of my Ipe grill island. Didn't take any before pictures but it had been outside for 3 years eith no cleaning or maintenance. It was in pretty rough shape. Stained with TWP 100 (2 Parts Dark Oak & 3 Parts Cedartone) Looks even better in the sunlight.

http://i1159.photobucket.com/albums/p638/marcus410/dcd8645a.jpg

http://i1159.photobucket.com/albums/p638/marcus410/408e831d.jpg

Here is a link that might be useful:

I came here this morning hoping to see photos of your HD'd deck and just found your grill island. :-( My bad, as I didn't read your earlier post thoroughly enough, and thought you were working on your deck this weekend.

BTW, copy and paste the "html code" link on your photobucket photo and it'll paste them right into the body. Easier for all to read.

I cleaned my deck with MD80 today. What a difference it made. It got rid of 90% of the black spots. The only problem with it is it did raise the grain of the wood some. So a light sanding is still needed. But the sanding will be so much easier than it would have been had I not used the MD80. I used the citralic acid on the 3 bottom boards in the below picture. I will give the rest of the deck a citralic acid bath in the morning. I also hope to get the sanding done tomorrow as well so that I can get a coat of stain on this thing by Tuesday. Learned a lesson and will not go 3 years without maintenance again. This is too much work.

What's the difference between citralic and oxalic acid?

BTW, thanks for the posting. I'm waiting on your results to decide what to pull the trigger on for my deck.

Citralic acid is what Woodrich Brand sells in their restore a deck kit.

http://www.woodrich-brand.com/product_p/cit02.htm

I finished all the prep work on my deck last night. It looks like a little rain for the next few days so I may not get the stain on till next week. Although it was a lot of work the deck looks almost as good as it did when I built it. I am confident that once stained it will look great!

Here is a picture from this morning. We had a little rain so the deck was still a little damp in a few places so that it why there are a few color differences.

Now it looks great, good job with the stripper and then neutralizing.

Looks great!

Marcus:
Have you put any stain down yet? Inquiring minds want to know....

Yes I got it on last week. Just forgot to post some pictures. I think it turned out great. Almost as good as it looked when the deck was new.

All these pictures where in really bright sunlight and make the deck appear a little ligther than it is

So here is my step by step.

Strip deck with MD80 stripper. Depending on how dirty or how much stain is left this may require doing it twice. It will without a doubt require scrubbing.

Give it a citralic acid bath. For me I still had some uneven coloring and some raised grain.

I decided t do some light sanding with 50 grit paper. About 1 hour per 100 sq ft.

I then applied the citralic acid again as I felt that it couldn't hurt and I had few areas that needed to be brightened some more. This made a big difference.

I then applied the Stain TWP 100 Series. ( 3 Parts Cedartone & 2 Part Dark Oak)

Here is my question??

How long do I need to wait to apply another coat of TWP? I would like to start building coats so as to never have to do this whole process over again

When I first stained my deck, I applied the 2nd coat the same day I applied the first coat (wet on wet), since that's what the directions on the can said. John does his farther apart.

When I redo mine, I'll probably do 3 coats, a week apart. And I'll recoat each year. On my first go-round I did 2 coats, then just re-did a few boards after 1 year. If I had re-coated everything it would have staunched the aging. I will also put multiple coats on the verticals that face west. The TWP can said verticals might only need 1 coat, but the sun has hit my boards hard, so they could have used additional coats on the sun-facing sides.

I'm still wondering if a full sand on the whole thing, with a floor sander, won't take less time than the 3-step process you did, considering step 3 alone, if I work at the same rate you did, will take me 6 hours. I can't imagine it taking me more than a full day to sand the whole thing. And I could do it all in one day instead of the waiting between steps for it to dry, etc.

I take it you removed all your balusters to do the chemical work?

Thanks so much for the info. My deck is about 2 years old and I have the exact same issues as you did. I will use MD80 as you suggested. How did you wash off the MD80 and how long did you let it sit for? Did you pressure wash it off? Thanks again.

Wow, saw this thread and thought i was looking at my garapa deck! At least the before pictures.

I have the same black marks and the EFC-38 did little to remove them. I've even pressure washed the deck and the black marks are still all over. I am hoping to follow what Marcus did above to clean it up. I am looking at the Woodrich site and i see HD80 but not MD80, and I can't find references to MD80 anywhere else.

Marcus, did you use HD80 or MD80? And if MD80, where did you get it? Is that one of those chemicals that they took off the market...?

I had the same issues as all of you and I used the cleaner and brightener made by woodrich. it was amazing the difference that it made.