Anhydrous Ferric chloride

make sure to not breath in the fumes that form when you mix it with water.
Whatever is left, make sure you pack it in a hermetically sealed container,
as it will try real hard to get any moisture it can :)
 
Hmmm,
Just thinking....I wonder what kind of 'antiqued/distressed' look you'd get by dropping a knife (maybe even a wet knife) into a bag of the stuff.....:confused:


If it works out you can call it the new 'shake-n-bake' finish .....:thumbup:
 
rashid11 said:
make sure to not breath in the fumes that form when you mix it with water.
Click to expand...

Additionally, besides being bad for you, the fumes are bad for any metal the fumes comes in cantact with, other knives, tools, your watch, eye glasses, etc...

So, be sure to have lots of ventilation; better yet, do it outside...

Bruce :D
 
A glass pyrex container with a plastic cap/cover should be ok for feric chloride, right? =P i've been looking at some of the powdered form and was wondering if pyrex would be a good enough container for the long term >_<
 
Glass is fine, as is most plastic. My tank is in PVC pipe. Metal is the only real no-no.

The gas is hydrogen chloride, or what you'd more commonly call hydrochloric acid. It is definitely not good to breathe. Unless you have an "acid cartridge" on your respirator, it will not provide very good protection, either. This is definitely something to do outside with a breeze at your back.

When you dissolve it, slowly add the powder to the water (preferably distilled) while stirring. Don't just pour water on the solid.

A preciptate should form. This not a problem chemically, but if you stir up the pot when you etch it might stick to the blade and cause a blotched etch.

The best way to make your own solution is to dissolve the powder in the water, wait a couple days as a precipitate forms, then pour off the liquid slowly into the final container.

Hope that helps a bit.
 
fitzo said:
Glass is fine, as is most plastic. My tank is in PVC pipe. Metal is the only real no-no.

The gas is hydrogen chloride, or what you'd more commonly call hydrochloric acid. It is definitely not good to breathe. Unless you have an "acid cartridge" on your respirator, it will not provide very good protection, either. This is definitely something to do outside with a breeze at your back.

When you dissolve it, slowly add the powder to the water (preferably distilled) while stirring. Don't just pour water on the solid.

A preciptate should form. This not a problem chemically, but if you stir up the pot when you etch it might stick to the blade and cause a blotched etch.

The best way to make your own solution is to dissolve the powder in the water, wait a couple days as a precipitate forms, then pour off the liquid slowly into the final container.

Hope that helps a bit.
Click to expand...

Mike, I was wondering - one of these days my supply of Radio Shack FeCl will be gone and I'll need to look elsewhere. With the RD stuff, I mixed 3:1 distilled water:FeCl. How will I get the same ratio/strength down the road with stuff I mix on my own??
 
I think I took a much less scientific approach :confused: :o

I found these neat-o glass jars at a yard sale the kind with the flip top lid.It says "hermeticly sealed" right on top.

I filled the jar 3/4 of the way up with distilled water,added a few scoops at a time until I got the right color....presto dip and etch.I did notice that after a little while that stuff on the lid got wet all by it self,very hygroscopic!

I did do it outside with good ventilation.

I remember that ol' rule of thumb from Hs science class "always add acid to water never water to acid" :eek:

Has anyone ever tried the "eidenburg" etch add a little citric acid powder to heat things up a bit....might be undesireable?
 
stole the question right out of my mouth joe

i just happen to have a little container of citric acid sitting around with no use, i wonder?

what say ye Fitzo?
 
kbaknife said:
Mike, I was wondering - one of these days my supply of Radio Shack FeCl will be gone and I'll need to look elsewhere. With the RD stuff, I mixed 3:1 distilled water:FeCl. How will I get the same ratio/strength down the road with stuff I mix on my own??
Click to expand...

Karl, here's a link to the MSDS for the RS Etchant. It says it's 32-45% by weight. I looked this up once before and others are about 36%.

So, you'll want about 9-10%. That means about 9 grams in about 100cc of water.

To put that in home terms, I'd add about a level tablespoon per 3.5 oz of water and see what that does for you. (or, a proud 1/2 cup to about a quart of water) You may have to add a bit more solid, but I don't think it will start out too strong.

Hope that helps.
 
Citric acid is slightly more acidic than vinegar, but much less than the hydrochloric acid which makes ferric chloride work. Citric acid oughtta work. Store bought white vinegar is about 7%, if I remember correctly, cider vinegar is 10% or more.

Mix 1 part citric acid to about 5 parts water. (Starting out stronger.) You can always add water. Don't use all your citric acid to begin with in case you've made it too dilute. ;)

Added: if you are asking if spiking the ferric chloride with citric acid will make it etch faster, the answer is yes. That said, why etch faster? The lower the concentration of acid, the greater the differential in the rate the two steels etch, up to a point. If you're doing damascus, the lower strength is better in terms of contrast.

All that said, i have dumped vinegar in my ferric chloride before and it has rejuvenated it a bit when it has aged too much.
 
There's some study on the web (GFI) that mentions positive effects of
adding citric acid (powder) to FeCl . It helps to break up some deposits
that form during etching .

As for storing FeCl, I advise reuse of an ole car window wash fluid jug. It
is much sturdier that yer avg milk jug and not fragile - like a glass container
is . If you break the jar and the stuff spills in yer shop, things will continue to rust for years.
 
fitzo said:
Karl, here's a link to the MSDS for the RS Etchant. It says it's 32-45% by weight. I looked this up once before and others are about 36%.

So, you'll want about 9-10%. That means about 9 grams in about 100cc of water.

To put that in home terms, I'd add about a level tablespoon per 3.5 oz of water and see what that does for you. (or, a proud 1/2 cup to about a quart of water) You may have to add a bit more solid, but I don't think it will start out too strong.

Hope that helps.
Click to expand...

Yes it helps - some!
Is this BEFORE I do the 3:1, distilled:FeCl mix?
Meaning, your recipe gives me the approximate strength of the R.S. stuff right in the bottle - right?
 
No, the tablespoons/water I mentioned should give you just about what your diluted Radio Shack stuff does. If you have a food scale, I can help better? Better yet, tell me how much stuff you want to have when it's all diluted??

Thanks for the cicada pics, btw! We both enjoyed them. :)
 
Karl, I thought with your moonshiners back ground mixing up fc would be right up you ally. Mike will get you straightened out......... :D
 
you can buy a device that measures density of solutions.
The name eludes me @ the moment. Something like $10.
It is a sealed glass tubes, graduated, with some weight
at the bottom. You gage the density of a solution by measuring
how deeply the tube dips into it under it's own weight.

The color of the FeCl solution should be mid-level caramel :)
 
rashid11 said:
you can buy a device that measures density of solutions.
The name eludes me @ the moment. Something like $10.
It is a sealed glass tubes, graduated, with some weight
at the bottom. You gage the density of a solution by measuring
how deeply the tube dips into it under it's own weight.

The color of the FeCl solution should be mid-level caramel :)
Click to expand...


It's called a hydrometer. It measures specific gravity (liquid density). And, yes it could be used, provided you knew what value you needed to shoot for. Color matching solutions is not a good way to do things unless one has two identical tubes with solution in them the same height and looking down through the tubes into a white background. With a good colormatching standards set, very good approximations can be made.

This gets a little more complicated than simply dumping some powder in a bottle of water. There are things going on that mean there will be a short learning curve with this stuff. First off, there is going to be some loss of chloride as hudrogen chloride gas. Then there is going to be a precipitate form (ferric hydroxide) and settle out over several days. So, chances are, calculating this on the basis of what's in the Radio Shack bottle is going to produce a weaker solution. My approach for Karl was to err on the side of caution and add a little more powder as he krept up on the proper concentration from below. I don't want anyone saying I had them make it too strong and it trashed their blade.

It's just as good an approach to make it too strong and do just like one did with the RS PCB Etchant: dilute to taste.

My best approach to shop chemistry involves buying a cheap food scale and measuring how much ferric chloride it takes with how much water to obtain what meets your particular needs the first time through and writing it down. Mixing it up by eye is simply not my way.

Chemistry lesson concluded....
 
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