Purpleheart & Muriatic Acid...

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Firefyter-emt

Firefyter-emt

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Ok so I bought an entire gallon of this stuff today at the hardware store. (glad it was only $5.00) :D I know this should kick the PH to a nice cranberry color, but what method to I get the acid to the wood?? Dunking?? Brushing?? vapor bath?? Once an application methos has been chosen, how long does it need to be "in contact" with the acid? And last but not least, once it has been removed will a water / baking soda be the best to neutralize the acid?

Thanks all!
 
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If I were you I'd fume(vapor) it. If you let the acid contact the wood there is a chance of not getting it totally out(it will soak into the wood)and could ruin the finish later. Baking soda will work for neutralizing but won't have the penetrating powers that the acid does. Basically it will be just a topical neutralize. People usually use Amonia to fume with. Be careful with the Muriatic Acid as it usually contains 44% HCL(Hydrochloric Acid) which will give you definite problems if you breath it. Probably should use a respirator with Acid cartridges unless you are use to working with acids. Another goodchemical for altering the color of wood is Potasiom Permanganate.But be aware it's a powerful oxidizer.
Brian
 
That is what I was leaning towards myself. I was thinking along the lines of a coffee can with some 1/4-20 bolts thru the lid. Slip the tubes on the bolt and add a nut and let them hang in the can from the lid
 
I use a natural bristle brush to apply it, and leave it until the wood is dry again. That will give the best color. The acid will neutralize itself over a couple days, and any finish can be applied.

The cranberry color is relatively permanent. I have some that is 5 years old and it has shown no change with normal exposure to indirect sunlight.
 
I always use heat to bring out the purple color. Put it on the mandrel and friction polish it with PPP wax. Have to be careful so that its an even purple or you can see bands...
 
OK.. lesson learned. Coffee cans, while being easy to find and easy to use, make very bad choices for a container! There appears to be a reaction with the metal. It turned the can gray inside and after 1/2 and hour the blanks are almost black.. Woops! maybe a glass container will be better and a closer eye on them. [8)]
 
Yep, Acids react with metal. That's why they are sold in plastic containers. Russ, what wood did you use it on. I've had bad luck applying direct to the wood. Also what concentration of HCL was in the Muriatic Acid. A non oily or oily wood, tannic based wood, etc. Just curious so I can experiment. Thanks, Brian
 
How I would do it is vapor it. I would use a coffee container ( plastic ) with lid put a hole thru the side the size of the mandrel. I would use a plastic rod not metal. put a little bit of acid in the bottom of the container and put the plastic lid on and check it in a few hours to see if it needed to be turned. its suspose to turn the wood a cranberry color. BUT I've never tried it
ken
slippery rock, pa
 
Originally posted by kghinsr
<br />How I would do it is vapor it. I would use a coffee container ( plastic ) with lid put a hole thru the side the size of the mandrel. I would use a plastic rod not metal. put a little bit of acid in the bottom of the container and put the plastic lid on and check it in a few hours to see if it needed to be turned. its suspose to turn the wood a cranberry color. BUT I've never tried it
ken
slippery rock, pa
Click to expand...

There are different plastic. The acid might just eat through the plastic coffee can in seconds. Use glass or ceramic.
 
This entire topic of adjusting the color of Purpleheart using acid is totally new to me. As long as I have been around, I'm surprised that I hadn't seen this discussed before. But no matter, always great to learn something new and that is a regular occurrence around here!!

And now for a question. If Purpleheart will change color with the application of a little acid, might not someone use vinegar, lemon juice or some other acid less potent than Muriatic? That stuff is pretty nasty and can cause big trouble if one is not careful.
 
True, but you are still dealing with the vapors, the liquid if you pour it into a smaller glass gar (could be nasty if you drop the jar) Plus the 1 gallon jug when it is being poured. I think it is a perfectly just concern.

FYI, the pen that was too dark did drop back down to a purple once I washed it in a baking soda / water mix and it sat over night. Still too dark for what I wanted though. I will play with this a bit more.
 
Vinegar is just Acetic Acid. Different properties and at a much less concentration(Vinegar isn't pure). Matter of fact, I tried buying some Acetic Acid about 7 years ago and it was outrageous in price. Had to order from Scientific Labs and under the Company name if I wanted it. I chose against it. Brian
 
Originally posted by kghinsr
<br />Randy
please understand you are NOT applying acid to the wood. You are using the vapors from the acid to color the wood.
Click to expand...

According to Russ' previous post, he brushes the acid directly on the wood!! Russ has a reputation for knowing what he is talking about!!
 
Originally posted by turff49
<br />Vinegar is just Acetic Acid. Different properties and at a much less concentration(Vinegar isn't pure). Matter of fact, I tried buying some Acetic Acid about 7 years ago and it was outrageous in price. Had to order from Scientific Labs and under the Company name if I wanted it. I chose against it. Brian
Click to expand...

Hey Brian: Not quite sure what your point is?? Are you suggesting that "ONLY" Muriatic acid will produce the color change?

As I said in my earlier post, I don't know the thing thing about this subject so I'm just trying to get educated. Will a reduced strength sulfuric or nitric acid work? Is Muriatic acid used simply because it is the best conbination of availability, cost and hazard or is it the only thing that will work?? Have you tried anything other than Muriatic acid to see what happens??

Have there been any other discussions of this subject that anyone can point me too? Thanks for any help!!
 
I have never been able to get any color change in Purpleheart with any acid other than Muriatic Acid (HCl), and I used the concentration sold in the swimming pool supply shops.

Others have said that any acid will do the color trick with Purpleheart, and that Vinegar would work, but they never stated the concentration and that thay might have been the difference.
 
A little background on myself: Although I'm no where near the expert that Russ is I have been refinishing furniture for the past 36 years and working with Chemicals for the past 23 years(I'm not a chemist but an enviromentalist). My point was I don't think there is enough Acetic Acid in venigar to alter the color. You can use venigar to disolve some yellow glues and hyde glue though. As for Sulfuric or Nitric. I've never tried suphuric on wood. You can use Nitric but be very careful and watch what woods you use it on. Some tannics in oak when combined with the Nitric will give an off gas(I've been told) I have fumed with Nitric though with good results. I don't recommend anyone using acids though unless they are well versed in the hazards, precautions, and protective measures needed to handle and work with them.
Exactly what color are you looking to obtain? Maintaining the purple? UV and oxygen arew what causes it to darken so a uv preventing finish(some catlyzed varnishes have this now)may work although I've not tried it. Russ, any idea if they would work. My biggest concern is that someone will try the HCL(Muriactic Acid) and get some of the vapors in their lungs(bad news if that happens).
Brian
 
I've done the muratic acid fuming before. Owning a pool cleaning service makes finding some acid really easy[:D] I turned the purple heart and left the tubes on the mandrel. I then just inserted the tube end of the mandrel into a empty gallon jug of acid. The little remaining acid was sufficient to turn the wood a nice cranberry color. BESURE to neutralize the the mandrel as soon as you are done fuming, DAMHIKT[:0] I also must not have neutralized the wood good enough because after being stored in a plastic tube for 6 months or so, it is as black as ebony[:p] The gold finish is now a satin also[:D]
 
I'm not an expert on chemistry at all. Muratic acid is nasty stuff, I won't let it in my shop in an open container.

Years ago I owned a zinc spin casting business, and used muriatic acid to turn the zinc black. I would buff off the zinc and have an antique silver finish. The fumes will rust equipment. I have some tools that are rusty because they were in the room I used the acid in.

If your trying to make purpleheart more purple, just set it in the sun for a bit and leave the muriatic acid at the store.
 
FYI... After trying it, and some of the comments here, I do have to agree. The sun is the best way to bring it back. The acid, while giving it a nice color, is not quite purpleheart anymore either. Oh well, live and learn!
 
I have experimented with muriatic acid on a number of different woods. I apply it directly to the finished blank in a light coat with an acid brush like you use for flux. I do not neutralize it in any way other than to make sure it is dry. I then lightly sand and finish with CA and have had no problems at all with the finished product.

Some of the woods I have tried it on and the results:
Mesquite--turned the wood a deep purplish color and really brought out the chatoyance
Osage Orange--turned the wood army green
Tigerwood--turned the wood a dark brown that was boring!
Massaranduba--turned the wood really dark red
 
This is a very interesting discussion. I believe it may open up a whole bunch of new ideas and interesting pen treatments. The use of acid to change the appearance of wood is not new. Makers of old style muzzle loading rifles regularly use an acid stain to bring out the figure in maple for stocks. Generally (in fact, almost universally) the acid is diluted and applied repeatedly until the desired effect is reached. Then the wood neutralized to stop the darkening. Of course, the water raises the grain and requires resanding, but that's part of the task of achieving a fine finish.
Stains used by rifle makers are available, here are two reputable sources:
http://www.trackofthewolf.com/

http://www.longrifles-pr.com/
 
I should mention one more thing. I am a bit of a galoot and use a lot of hand tools. I did this in a sealed coffee can on my workbench. I now have light rusting on my chisels, planes, drill press shaft and a few other tools. DO NOT use this near bare metal.

BTW, my planes and drill press are treated with Boeshield T-9 This was all just from the fumes working with it while it was uncovered. Not happy about that I will tell ya.
 
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