Thoughts on Oxalic and Ipe

[plainpainter 217]

Russell among others sells a milder acid that contains citric acids - it's selling points being that it doesn't harshly bleach the wood like oxalic and it improves your spread rate - while I am inclined to agree, I had another thought swimming in my head of mine - the one that Ipe is a hard wood to get anything to stick too. Then in my head I did one of those 'one plus one is two' moments.

If oxalic 'opens' up the wood much more severely than a citric blend - wouldn't it make more sense to use that on a wood like Ipe - to clean out the 'pores' and get a better penetration of your stain, especially woodtux.

And I am not really interested in people talking about the 'integrity' of the wood - and how we are here to preserve it. I am talking about the top few mils. I mean come one - not one of us hesitates to sand down a few mils when confronted by a nasty restoration job. Can't we just all agree the top few mils is fair game when it comes to getting stain to adhere? I mean in an inch you got 1,000 mils to play with before you run out. Floor sanders wack out your hardwood floors after the 3rd sanding. What's the big deal about getting that top few mils cleaned out for better penetration of stain. A penetration that once in place will stop or put a great damper on wood decay and allow longevity of your wood.

[RPetry 564]

Daniel,

I got off the phone with Jim Foley a bit ago. A change of plan.

Please bear with me as I have never used oxalic acid before on any exterior wood. I am also married to a terrific wife who loves our ipe' deck. Letting it sit stripped for a year cost me a few points. We bought a new teak dining set last year that I also left alone to weather over the summer, another few lost points, and that will be stained when the weather warms up this year. Anyway, bottom line is this.

From what Jim has told me, the ipe' will look very different even after staining due to the color difference of the wood resulting in the "bleaching" or brightening differences of oxalic as opposed to citric. Having a two toned ipe' deck is not in my best interest. I think I've pushed my marital bliss enough, so let me propose this.

The top rail running the length of the deck is 2 x 6 ipe'. It gets full sun, nearly all day. It is just as exposed to moisture as the deck boards. Half the top rail gets oxalic, half citric. Same stain, same quantity. I'm going to try and get two separate apps of RS into the horizontal ipe' if and when temps warm up some.

The bottom top rail fascia board on the outside of the balustrade is 18 yr. old PT. Same thing, half oxalic, half citric. The rest of the deck gets straight citric.

Do you think this is good enough for our purpose? If not, let me know and I will not treat any of the wood with oxalic.

Thanks.

[plainpainter 217]

Rick - I definitely don't want you to put your marriage at risk! LOL.

I think the top railing is a geat proxy for what will happen in general,

as well as the fascia board. But I don't know about equal amounts

of stain - if anything saturate both sections like you would normally

do , and perhaps keep track if there is a difference in the amounts

that the wood accepts. Although this may be hard to do, since there

is so little area to begin with. Maybe a pre-measured coffee can

of stain - and see how many linear feet you get between the two

different sections on the railing? Actually I think that would be a

great experiment. But yeah definitely do the decking like you would

normally do - but take pics after brightening to see if there is a visual

difference in brightening between the acids. And how the railings look

after staining if the difference is still there - and of course, how well

do each hold up.

If you think about it - if you just look at a railing - which is basically

a two dimensional surface - if there is a difference, perhaps just treating

the railing will give a more obvious indication vs. two larger areas. Heck auto body painters can feather two slightly different shades so well on a car I can never tell where a repair was done. But a linear railing is just a line that would transition instantly from citric to oxalic - and would be much easier to repair later on if there is a great difference.

[RPetry 564]

Daniel,

Yeah, stain quantity difference over such a small surface would take the National Bureau of Standards. As I'm sure you know, ipe', due to the density of the wood, does not take much stain. Thats an overstatement, takes hardly any stain compared to other woods. Even with a paraffinic oil, it will be interesting to try and get two separate apps into the wood. The old PT board below the top rail is the exact opposite.

This could be interesting. Same woods, same age, same moisture and sun exposure, same stain. I had hoped to test another stain product at the same time in a small area but that did not pan out. In retrospect, we probably have enough variables going as is.

I am going to have to wait a while before staining, it is just too cold here for the next 4 days to consider. I will wait for the ipe' to dry out from cleaning, do a light random orbital sanding with 50 grit, and then apply the acids. When I can get to applying stain is up to the weather gods.

[Beth n Rod 1,279]

Russell among others sells a milder acid that contains citric acids - it's selling points being that it doesn't harshly bleach the wood like oxalic and it improves your spread rate - while I am inclined to agree, I had another thought swimming in my head of mine - the one that Ipe is a hard wood to get anything to stick too. Then in my head I did one of those 'one plus one is two' moments.

If oxalic 'opens' up the wood much more severely than a citric blend - wouldn't it make more sense to use that on a wood like Ipe - to clean out the 'pores' and get a better penetration of your stain, especially woodtux.

And I am not really interested in people talking about the 'integrity' of the wood - and how we are here to preserve it. I am talking about the top few mils. I mean come one - not one of us hesitates to sand down a few mils when confronted by a nasty restoration job. Can't we just all agree the top few mils is fair game when it comes to getting stain to adhere? I mean in an inch you got 1,000 mils to play with before you run out. Floor sanders wack out your hardwood floors after the 3rd sanding. What's the big deal about getting that top few mils cleaned out for better penetration of stain. A penetration that once in place will stop or put a great damper on wood decay and allow longevity of your wood.

Ok, pursuing that logic regarding Ipe', now how about these questions:

1. What difference do you think it will make a few mils further down?

2. Does your thinking entertain the possibility that the wood is less dense or more open further down than at the current surface as it has been prepared?

3. Are there any more or less extractives a few mils deeper?

4. What is the process going to have to do to effect a few mils deep?

5. If using a stronger acid to 'open' up the pores (which are primarily in hardwoods, Soft-woods have capillaries) and keeping in mind the pores are extremely small and shallow, do you think the color will last longer as a result?

6. Given the fact that most extractives are impermeable to begin with and give the wood it's natural resistance to decay and insect repellancy, do you think that you can limit the depth of the acids activity and still have a surface that will hold a stain?

7. Do you think the wood that is left after your process will still have any integrity to last longer than otherwise?

8. After considering the previous questions, do you still think it is a viable option?

Rod!~

[Beth n Rod 1,279]

Using two different acids on the same deck will produce a color variation .I find letting the wood sit produces the best results for more depth of product.

How did you come up with that one James?

They are talking about 2 acids mixed and dissolved into the same solution. From what I remember in chemistry, the compound does not formalize into two separate bleaching reactions but one where the pH is balanced between the combination of the two and the result is even.

Rod!~

[plainpainter 217]

In regards to your last post, Rod - James was right, the two acids aren't being dissolved into the same solution - there will be seperate solutions to go on seperate areas of the deck, well now seperate parts of the railings.

In regards to your second to last post - I am no longer entertaining anymore discussion in this subject. I had an idea - it may be wrong or right - it's just an idea with a little logic behind it, at this point I would rather not imitate the ancient greeks in trying to guess how many teeth a horse has by using logic - I'd rather just go up to the silly animal and count. In other words let's stop discussing - do the experiment and see what happens. Afterall that is the definition of science - validating theory through experimentation. My theory doesn't have to be Right - it just has to seem plausible enough to try a little experiment. Without getting too technical about the different porosity patterns of soft vs. hard woods. The fact of the matter is that Russell talks about this on his site about oxalic bleaching more of the compounds away - perhaps oxalic may not actually damage the cellulose walls like UV does - and leave a nice honeycomb structure for stain to enter and form an anchor - or maybe it won't. At this point let's just see what the results of a small experiment are.

[Beth n Rod 1,279]

In regards to your last post, Rod - James was right, the two acids aren't being dissolved into the same solution - there will be seperate solutions to go on seperate areas of the deck, well now seperate parts of the railings.

In regards to your second to last post - I am no longer entertaining anymore discussion in this subject. I had an idea - it may be wrong or right - it's just an idea with a little logic behind it, at this point I would rather not imitate the ancient greeks in trying to guess how many teeth a horse has by using logic - I'd rather just go up to the silly animal and count. In other words let's stop discussing - do the experiment and see what happens. Afterall that is the definition of science - validating theory through experimentation. My theory doesn't have to be Right - it just has to seem plausible enough to try a little experiment. Without getting too technical about the different porosity patterns of soft vs. hard woods. The fact of the matter is that Russell talks about this on his site about oxalic bleaching more of the compounds away - perhaps oxalic may not actually damage the cellulose walls like UV does - and leave a nice honeycomb structure for stain to enter and form an anchor - or maybe it won't. At this point let's just see what the results of a small experiment are.

We have been using a blend of citric and oxalic for years, and the decks we do never, ever neutralize/brighten unevenly due to this. Ever. It just doesn't happen.

Beth :cup:

[RPetry 564]

Beth,

We have been using a blend of citric and oxalic for years

This little experiment that Daniel proposed does not use a blend at all. One section of the 2 x 6 ipe' toprail and PT skirt will be neutralized/brightened by 6 oz./gal. of citric acid only. The other section of toprail will be treated by 6 oz./gal. of oxalic acid only.

[Beth n Rod 1,279]

Sorry, been busy this week and a little behind on the threads. But I still like to ask questions when someone asks about doing something in a new way. Innovation is what it is called and some great ideas come out of it and I was just trying to find out what your 'theory' was.

Rod!~

[Beth n Rod 1,279]

Beth,

This little experiment that Daniel proposed does not use a blend at all. One section of the 2 x 6 ipe' toprail and PT skirt will be neutralized/brightened by 6 oz./gal. of citric acid only. The other section of toprail will be treated by 6 oz./gal. of oxalic acid only.

And how does gravity prevail? Unless you are applying with a more precise method like a brush, the two will blend where they meet.

Rod!~

[James 624]

If you use the two acids seperately. There will be a brighting variation.

[Beth n Rod 1,279]

Rick,

Sorry! I misread it. I thought he was saying the two acids would separate from one another after being mixed together. Well, I guess it is time for more coffee for me... :cup: :cup: Didn't mean to confuse things...

Beth

[RPetry 564]

Rod,

Initially, to test Daniel's proposition, I was going to do 1/2 of the complete deck with oxalic, the other half with my normal citric. After speaking with Diamond Jim, decided that my wife and I did not want to live with a two toned ipe' deck. Please realize that I have never used oxalic on wood, and did not understand that the "bleaching" or coloring of the ipe' would be so different between the two acids.

I think I can pretty accurately brush the oxalic onto the one section of toprail without mixing with the citric on the lower spindles. Some oxalic may drip on the deck floor but thats ok.

[Beth n Rod 1,279]

Ok, go tinker with the acids and let us know what you turn up.

Rod!~

[plainpainter 217]

Ok Rod - in a very naive way of thinking, my theory was that since it was proposed that oxalic acid 'opens' up woods more, and the qualifier for this - is that you get a worse spread rate, i.e. you are using more material. My initial thoughts were that more material is getting soaked per unit area of decking. My next thought was perhaps if this is true, the stain may be better anchored - not by any chemical adhesive property - but by more of mechanical adhesive property. Now since a 'film' forming stain, leaves a coating with a hard surface tension - they may benefit more than a parafinnic stain - but at least Rick is willing to try - or heck - now there is more room for penetrating stain as well - so maybe it's life will endure as well. That's my theory - without getting too technical or trying to overthink all the variables involved - a simple experiment should either support or contradict my basic assumption that if you are getting 'worse' spread rates perhaps you are building a more durable coating. That's all.

[Beth n Rod 1,279]

Daniel,

We are interested in the results you get. Keep us posted. :)

Beth

[PressurePros 248]

Ipe has to be approached from a different perspective that anything else. Ipe has so much natural oil that most oil based stains don't have a chance at any type of finish longevity. As much as this may be loathed, you have to chemically age the wood (ie remove some of its natural protection). We do this via cleaning and pH balancing.

Keep in mind that you then have to apply the right type of sealer. Putting a non drying oil on is fighting Mother Nature. Its going to try and dive in, get stopped by ipe's natural defensive sugars and oils, sit and wait for the next rainfall and then leech out. You need a resin containing, curing product (ie a "sealer" not a stain).

Rod/Beth asked what benefit was achieved by doing this chemical aging process. The carying oils are able to take pigmentation a little further into the wood. With the right product that cures in the right amount of time, the pigmentation is then locked into the wood. Ipe and other hardwoods don't need to be "conditioned" like cedar or pine. You just need to be able to anchor pigmentation in the wood. (to borrow Dan's term)

[RPetry 564]

Daniel,

Got the oxalic, we are in the wrong business. $8.55 at Ace for like 12 oz. Anyway, the wood is ready for acids but the weather is very cold. Did not get above 41F here today and was windy. Did some deck repairs for an upcoming job and had to wear gloves!

What do you think? Wait until warmer weather? The ipe' dries out in a flash so on a warm sunny day can probably apply the acids to each test section, and put a 1st app of stain on within an hour or two.

Let me know. This is your experiment, I'm just the guinea pig.

[plainpainter 217]

yeah wait for warmer weather - we can wait - clean and stain on a day that you would wait for if this was a customers deck. Why mess with a good experiment - I'm patient. Anyways - in the future if you like the results - you can buy oxalic at thechemistrystore.com for far cheaper money. I thought I saw one of those percarb pouches for cleaning wood decks from Wolman's at Ace - $20! Can you believe that? Go the next aisle over and you can purchase a tub of oxi-clean and TSP and still have money left over for a candy bar. And clean ten times as many decks!

[RPetry 564]

Daniel,

I buy 50 lb. bags of food grade citric acid from thechemistrystore.com for ~$100 including shipping. Remember the days when I first started out and used Wolman products. Their 2.25 lb. wood cleaner / brightener was something like $19 and this was 5 yrs. ago! Thought I was smart and would special order 10 lb. jugs of the stuff. Did not take too long to learn better, more cost effective ways to obtain better chems and stains.

Your experiment has got me thinking of something I have wanted to try. Citric alone works fine for me by and large. But on cedar with the cheap fasteners most deck builders and fence manufacturers use, there is that nasty looking nail bleed. I've been thinking of mixing one part citric, one part oxalic, and one part phosphoric acid to use on cedar with nail bleed problems.

Not that is is going to solve the problem, but probably help in the short run at least until you are done staining.

Waiting until warmer weather is, I think, a good idea. I'll stain with RS in the mid 40's, but do not like to use chems until air temps are 50 or above. Only problem is I've got a full book of customers going out until the end of May and my advertising starts this coming week.

Arg! After I get my own ipe' done, I've got the 'friggin teak to do! Where there's a will there's a way. We will have some fun with this as no one can predict if, or if there will be any, concrete results.

[plainpainter 217]

Hey Rick - I got a funny suggestion - try neutralizing one chair with citric and the other with oxalic - since they are separate pieces of furniture - you won't be able to tell the difference in tones. Juggling 3 different ingredients will be tough to keep track of. Why not just use mostly citric and a little oxalic - and then increase the oxalic a little at a time until you get the results you want. And then have a separate solution of citric and phosphoric - and do the same thing. Putting all 3 at the same time this early in the game will have your head spinning in confusion.

[RPetry 564]

Daniel,

I was referring to cedar. The furniture is teak. We spent over 2k for it and there will be no experiments on this wood! It will get a light percarb on the wood, hand brush, and hose rinse off. Straight citric neutralizer / brightener. Lambswool Ready Seal into the wood. Twice.

Good thing you are not a boarder in my house. My wife would either kill us both or walk out on me! Bless her warm soul, she does appreciate good wood!

[James 624]

Putting a non drying oil is working along with mother nature to prevent the wood from turning grey. That is the only object with Ipe. Putting a sealer on that cures is fighting the oils in the wood and mother nature. This creates more problems in the future . So it wood be better to use as little of a curing product on Ipe as possible so you can handle any difficulties easyer.

Ipe was made to be left alone and turn GREY. Those are the happiest people. Talk to the people who spent 10 grand in 10 years sealing it and the people who paid 1000 dollars cleaning it. I have both. Then I have people who have gone through all the sealers! Mad at the world until they found me ( LOL). And now there's WTW and Flood Something. ( I am sampling both) I still like they way i do it better so far.

[Beth n Rod 1,279]

Ok Rod - in a very naive way of thinking, my theory was that since it was proposed that oxalic acid 'opens' up woods more, and the qualifier for this - is that you get a worse spread rate, i.e. you are using more material. My initial thoughts were that more material is getting soaked per unit area of decking. My next thought was perhaps if this is true, the stain may be better anchored - not by any chemical adhesive property - but by more of mechanical adhesive property. Now since a 'film' forming stain, leaves a coating with a hard surface tension - they may benefit more than a parafinnic stain - but at least Rick is willing to try - or heck - now there is more room for penetrating stain as well - so maybe it's life will endure as well. That's my theory - without getting too technical or trying to overthink all the variables involved - a simple experiment should either support or contradict my basic assumption that if you are getting 'worse' spread rates perhaps you are building a more durable coating. That's all.

On Ipe' the spread rate is pretty good but the penetration is the problem as you have noticed and I was trying to understand the theory you postulated regarding the first few mils.

In our experience, the oils do a great job at penetrating and filling the pores, and the products containing any solid content such as pigment and resins sit mostly on the surface with much less penetration.

I have to chime in that I favor a curing product to hold onto the surface to give longevity and therein lies my intrigue in your thought stream.

To finish, I am not yet convinced of the durability factor in making a coating last longer but a more flexible coating. WTW has shown in the past to retain a certain amount of flexibility after curing but wear and traffic erodes the surface presence leaving an uneven pattern. Ipe' is the latest "fad" here and people who like to entertain love to have it looking good for as long a possible and have the money to throw into it. I am almost to the point of considering offering a twice a year service for those who want to keep it looking great all year long.

Rod!~

[RPetry 564]

Ipe' may be a "fad" for those that like to impress neighbors and other socialites. But for some of us that work on decks daily and have some appreciation of quality wood, ipe' may be near the pinnacle of natural exterior wood. Finished, unfinished, or halfway. If only the Atlantic City boardwalk could talk.