Iron Oxide(S) And Rust Formula

[potziller]

 

 Hi folks,

I am a newbie to this forum  and a resonably new to ceramics.  Can someone tell me the practical differences between 'rust' and the 'iron oxide'  that is mixed up in the evening school classes I attend?  I've sussed that rust have extra OH and H2O groups, so why can't I find any topics that say "I collect local rust" and add it to my..........(pots/glaze recipes/etc etc...).  'If I don't have to pay for it, I'm interested!'  V  

[OffCenter]

 

 Hi folks,

I am a newbie to this forum  and a resonably new to ceramics.  Can someone tell me the practical differences between 'rust' and the 'iron oxide'  that is mixed up in the evening school classes I attend?  I've sussed that rust have extra OH and H2O groups, so why can't I find any topics that say "I collect local rust" and add it to my..........(pots/glaze recipes/etc etc...).  'If I don't have to pay for it, I'm interested!'  V   B&W Gulls.jpg

 

Even though none of the main three Iron oxides used in ceramics are very pure, they'd all be a lot purer and stronger than rust. Maybe you should test it out and post a topic titled "I Collect Local Rust" and let us know what you discovered.

 

Jim

[Bob Coyle]

I've heard of people making RIO (red iron oxide) from fine steel wool soaked in a weak acid solution like vinegar, but why do this when the pure stuff is so cheap and a much finer grade?

[atanzey]

...but I'll bet the rusted fragments of that steel wool would make some cool effects dusted on top of a wet glaze application!

 

Alice

[Marcia Selsor]

That is what Linda and Charlie Riggs use on their beautiful saggar pots.

 

Marci

[oldlady]

to the newbies who have not yet stocked up on glaze material to make your own glazes this is a perfect topic for you to read.  materials used in glazes vary in cost from low to high depending on the ingredient AND on the quantity purchased.  whenever possible buy whole bags of those things you will use often, silica, frits, whiting, whatever comes up often in the glaze recipes you read and use.  whole bags make so much sense because you will not have to worry if the material has changed since you last bought it.  if you only bought 5 pounds of something, you will run out of it and must constantly worry that maybe this new 5 pound bag is from a different source and will react differently in your recipe.  finding that out after glazing a whole kiln load of work is painful and expensive.

 

if you have purchased a 50 pound bag of something, you will need to store it safely and make it easy to get at when needed.  never leave it in the original bag and assume you will just dig out what you need each time.  notice what happens when a bag gets dusty and your scoop scrapes against the loose flap of the bag.  you will make a mess and create unnecessary dust which is unhealthy to breathe. you will move that bag several times in the years you will use it and each time the paper gets weaker. instead, SLOWLY load your 50 pound bag of stuff into a large plastic bin keeping dust down as you do it.  Rubbermaid makes great ones that last for may years without cracking.  some of the other brands of plastic bins are brittle and will break more easily.   these bins allow you to open the top fully so you have complete access and a space to spill something if you happen to do that.  use a clean scoop to remove the material from the bin and transfer it to your measuring container slowly to prevent dust.  scoops can be bought at Walmart in the pet section for about $2 each.  a couple of them is enough for most people and they are easy to clean when used for most materials.  

 

getting to the red iron oxide mentioned in the original post, yes, i bought 50 pounds of it in about 1991 for about $12 and still have at least half of it since i rarely use brown glazes.  and in this case,  i have a small dedicated scoop located inside the 18 gallon tub that holds it because red iron oxide is so messy i never want to have to clean up a scoop that has been contaminated with it.  someone will inherit about 25 pounds of it someday............................and a very messy little scoop.

[Pugaboo]

Oldlady - thank you! I never thought about it that way. Being a beginning potter I have not started mixing my own glazes yet but now that you explained how things can change from bag to bag I will keep that in mind when I do so. I never thought about the fact that it won't go bad thinking more along the lines of a baker and needing fresh ingredients that only small amounts can provide. It's a good thing to know for the future.

 

Terry

[oldlady]

yes, the difference is that the ingredients in glazes are stable minerals and not subject to attack by bugs and such like baking ingredients.  just keep them covered and safe from dampness.  storing paper bags on a concrete floor is asking for trouble. plastic bins with tight covers are best. 

 

the only thing to buy in smaller quantities are the very expensive things, cobalt oxide comes to mind.  one pound is enough for years.  those tiny bags in the supply stores are expensive on top of expensive because someone had to measure out that tiny amount and put it in the bag.  yes, i never had any money to buy this stuff either so each time i had a few dollars i bought something  in a large amount.  it builds up.

 

OK ALL YOU EXPERTS!  THESE ARE NEWBIES SO DON'T CONFUSE THEM WITH ANHYDROUS ANYTHING!

[clay lover]

Very timely posts for me, this is my next studio addition. I have been using s glaze mixing service, but need to set up my own.

I am going over my most used glazes looking for common ingredients. It would be nice to have common sized containers for the 50lb. bags. Are the 50 lb bags of different ingredients sort of the same size? What size containers should I be buying for the bags, or should I get the bags in and then go shopping for them ? I have ample storage space for the large containers in another out building, but would like to set up a clean, climate controlled mixing room.

How many lbs. of silica, frits, that sort of often used, would you plan on having on hand in the mixing room ? I could restock these intermediate containers from the big bags as part of monthly studio maintenance, but would not have to go to the hot/cold storage every time I wanted to mix a glaze test.

I understand that colorants are small amounts, and have been buying them when the price goes down, for a year now and have a supply of most. Also have the scale and space in the main studio to set up a mixing room.

[Bob Coyle]

I try to batch up just before I run out of a glaze. Then I make a test tile of the new batch and run it in the kiln load of pots from the old batch. That way I avoid a whole kiln load of bad surprises. I do this even if my ingredients have not changed... you can always get distracted and weigh something wrong.

[oldlady]

i am trying to attatch a picture of part of my studio showing the Rubbermaid bins, tubs, whatever name you like, that hold my glaze ingredients. hope it works.

 

the bins are different sizes and colors because the store only carried one type at a time and these were purchased over a number of years. who knew there are "trends" in storage containers?   they are still flexible, Sterilite gets brittle and cracks.

[oldlady]

IT WORKED!  i don't know how the first pic came up first.  oh yes, i added it after the first post appeared by hitting "edit" at the bottom of the screen.   so it would be the only thing added and it wound up first.  hmmmmmmmm..................

 

boy, the studio was a mess that day.  i was still using brown clay.

 

(yes, jim, that is a giffin grip on the shelf.)

[oldlady]

clay lover, when your bags are ready to pour into the bins, wear your respirator and lower one end of the bag into the bottom of the bin and slit the paper across the bottom of the bag with a sharp razor knife.  the paper is strong and most things are double bagged, so be very firm on your first cut so it doesn't fray the paper and require a second or third cut.  raggedy cuts cause dust.  you are the master, use that tool firmly!  and use a new blade.

 

once cut, the product will flow out into the bin as you slowly  lift the high end of the bag as it empties.  with practice, you will hardly create any dust.

[Pam S]

Regarding materials storage, make friends your local pizzeria. Most of the ingredients they use comes in square, 5 gallon buckets with tight fitting lids. They are often glad to give them away. I use them to store large quantity glaze materials (GB, frits and so on) as well as for mixing large batches if glaze. They stack very neatly and take up less space than round containers.

[clay lover]

Wow, who knew? square bins for free is sounding good to me. Oldlady, thanks for the pics. Can you open and scoop out of the big totes without having to pick them up?

[oldlady]

yes, that is the whole point of using them.  the floor here allows them to slide, the ones on the top shelf slide also but i have a knee under the edge to keep them from falling.  the support system on that wall allows for an incredible amount of weight.  most of those bins are nearly full and i juggled the sizes so they fit well together between the supports.  alphabetical order is best for me.  i know the chemists want to put glass formers and clays and such together.  alphabet is easier for me.

 

free buckets sound great too.  i get mine from the local supermarket with a bakery.  icing comes in two sizes and both are useful.  some stores won't give them away because they fry things in their deli and use the buckets for old grease. and some stores are now getting icing in thick plastic bags.  ask several places and make sure you get lids!   the donut shop in florida closed so i lost a great source. 

[Graeme]

I used to put steel wool in some stable glazes, for a nice "spotty" effect. First, I'd put some steel wool inside a pot to be bisced.  The steel wool would then crumble easily, so if you wanted to weigh it, it was easy to handle. In reduction, the spots could move a bit, which is why I recommend using stable glazes. And I think the spots show up better in pale glazes. 

Have fun.  Cheers.  Graeme.

[oldlady]

steel wool sounds like fun in a single color glaze.  i do not fire in reduction but i might try it in the yellow rutile glaze on one of my Empty bowls.  thanks.   i have tried sprinkling some of the bowls with things like copper carb and ilmenite.  does not sprinkle without adding rice to the shaker.  breathing it is very bad so i did it outside.  not much of a result.  steel wool sounds like a great substitute.

[Mark C.]

If you are doing a lot of pottery- say full time I suggest buying all materials in bulk. In the long run you will save a lot as well as have a constant supply of materials that do change over time batch to batch.

If you know other potters get in on a large bulk buy its even more cost affective.

mark

[Ben]

Look in the local phone book for rebar. You need a rebar fabrication shop with a bending machine or a rolling machine or a straight and cut machine.

The rebar comes from the mill with scale on the outside. The outter layer is mostly black iron oxide. When the bar is bent this stuff flakes off. There will be ooddles and gobs of this stuff available in and around the machine.

take a bucket to collect the scale and see if you can't trade them lunch form their favorite take out place

bring it home and bisque fire it in a larger pot and it will convert into red iron oxide and will break down a little to smaller finer particles.

Mix with water and sieve out the big stuff and give it a try in glaze

 

 

certainly not cost effective but could be a fun local resource

[Marcia Selsor]

I have always mixed my glazes and bought in bulk. But some things you don't need in 50 pound quantities...like tin oxide, cobalt, borax, rutile, titanium dioxide, etc.

Bulk things are like talc, epk, ball clay, whiting, lepidolite, silica (325 mesh for glazes), gerstley borate, bentonite, etc.

 

For those older potters, let your families know where to donate them in case of death. Disposing untested chemicals could cost them a bundle. Donate them to other potters or college programs. Testing can cost upwards of 10,000 if they are unknown and treated as hazmatts...just saying...something to consider

 

Marcia

[potziller]

Hi folks,
as yet, no 'local rust' test pieces to show and tell; so here's an tile experiment with copper wire which has been followed through to completion. Single strands of copper wire were wrapped around a bisque test tile (yep, it's a bit of a pot that died on the wheel!). The tile was then dipped in clear and blue glaze and fired cone6/stoneware.
 
Now for the numbers/images.

 

Image [A] =  Overview.  

Graphic lines 1) 2) & 3) -  show where the thin copper wire was wrapped.  Line 4) shows where a single wire of much thicker copper was wrapped.  Copper wire thicknesses are shown in image [E] & [F].  Yep, those are thumbnails!

 

Image , [C] & [D] = close-ups!
 
The types of light the photos were taken in is also recorded.  I've done my utmost to get the images looking 'as is'.

Drawing attention to:

Image [D]: the resulting reflectiveness is an illusion of the photographic process and doesn't have this level of shininess in 'real viewing'.  Just happened that I caught the highlight bang on max!  Though this metallic 'highlight' obviously there in the photo, images from a camera are a different experience that with the human eye.

Also, with normal eye-sight my eyes cant' resolve the bubble in the glaze as shown in image.  Neither can I see the texture in it's full glory as illustrated by image (and I have just had new glasses).

There's more................! 

Copper wire wrapped around bisqued tile is never (although I'm sure someone out there can manage it!) gonna hug tight to the tile in all places. That may have effected the how the copper runs with the melting glaze.

 

Image [A]  show that the copper runs and collects through the melt. 

Image [C]  shows the copper 'really going for it!'
 
For extra points, the exceptionally observant of you may suss that the test tile has been slipped before bisque firing.   The top third of the bisque was fired with added white slip, the bottom third, black – which fired up blue!  The middle has no slip added and is just clay body, plain and simple.

I think that covers it!
Enjoy!

V:)

 

[Marcia Selsor]

I have been using copper wire but not on glaze.I have been using it in sag gars.I like the green flashing we both are getting.

[TJR]

Potziller;

You could get the same effect by painting copper carb on your bisque tile, sponging off the high parts ,then glazing.

I like the blacl slip effect. Obviously your slip has cobalt in it.

Go to the hardware store and get some brass dust from the key cutting machine. It also contains copper.

TJR.

[potziller]

S A double grrrr erh.  Sagger!     Yes the green flashing is good! 

 

Are all the marks on your pot illustrated copper wire, or are more densely pack markings in the mid of the pot something else?  I was going to remark that the green flashing seems to be (in the image supplied) at the top, as thus one could conclude................but if you're using a number of materials on the outside.......!?

I Cant see from the image supplied, but has the copper burn fully flat or does it leave a texture?  And what temperature did you fire the pot illustrated at?  Sagger is something I can do with the college kilns, but firing temps are limited to bisque, earthenware and stoneware (approx. 900, 1100 and 1260 C respectively).  I did forget to mention that the copper experiment I did was in Oxidation (1260 C).
 

One more little detail that could prove useful to point out.  Image shows a gap between the clear glossy glaze and the blue glaze.  Here there is no green 'flashing' bordering the copper melt.  Also with image [D] (where I make mention of the high metallic highlight), it's the clear glossy glaze that boarders and overlaps the copper melt that gives rise to the highlight/high sheen.

 

I have an inkling that I'd like to try a thin copper wire wrapped on greenware and see how it goes in the bisque and subsequent glost (glaze) firing.  Now where's that powdered copper?

V:)