Hi Erin, it shouldn’t matter in the short term, but in the long term it is better to have a well fitting lid, as this will slow the rate at which the vinegar changes pH. You want it to stay acidic, which is why I suggest topping it up with more vinegar each time you use it.
No, I always do straight vinegar and iron. I have seen other people use water, but I’ve gotten far better results from vinegar especially while it is still fresh. Here’s an article I wrote about that.
Hello there!- just found some rusty bits yay! Just out of interest – what effect has the amount of iron being used? Like the more the more powerful it’ll be ( = using less of it ) – or maybe it could become say too strong? Topping up with vinegar is ok I read – can one also add new irony bits at a later stage and still use the mordant directly or would I have to wait a certain amount of time again? This is already fun! Thanks a lot 🙂
Yes, when we use them in week 2 I’ll talk about how you need to use more if it is weak, or less if it is strong – but to a certain extent, the fabric will only absorb so much anyone, so it kind of regulates itself. Yes, you can keep adding more iron over time along with more vinegar – although even one piece of iron can last a long time, so you’ll find you won’t need to do it often!
I also make pottery and use iron oxide as a ceramic colorant. Could I use the powdered iron oxide as a mordant? I know this course is more about using everyday items, but I’ve had a hard time finding rusty metal around my house. Thanks!
Sure, give it a try! This course is about using what we have, so that’s perfect. It might be better to dissolve it in vinegar then add to the water when we use it in week 2, but I haven’t tried it myself so can’t say for certain.
I made some iron mordant this time last year from your ebook Plant Poetry, haven’t used it for 6 months though its still in the jam jar i made it in, will it still be ok or should i start again?
Hm, I can’t find white vinegar in any shops. I’m kind of surprised, there’s only distilled, white wine vinegar and malt. Any of these substitutes that might work best?
Yes, you can put it in before it is rusty, it will just take a little longer than using rusty iron. But pre-rusting it yourself will also take time, so it’s easier to just put it in the vinegar as is.
How long do you need to leave it before you can start using it? I found a iron camp oven which was left outside and has gone really rusty so I’m just going to fill that up with vinegar. Also thankyou so much for this course xx
Just love your course – gentle clear teacher So I started my iron mordant jar a year or so ago and recently topped up with fresh vinegar It looks sooo potent ( almost dangerous)- the lid has rust crystals and it’s a thick almost syrup It is in a glass jar- safe – shall I remove the rust things and dilute – disposing of half liquid ???? It’s a monster and possible far to strong… I’m a bit behind the classes but hoping to work ( NBT) with parents who have no self time as their kids have Autism …. art teacher embracing nature -Sally
Hi Sally, yes you could strain the metal out to stop it getting stronger. And then just use a very tiny amount to mordant with. If your fabric goes noticeably yellow, you will know that you have used too much, and can ‘flush’ the excess off by soaking in plain water.
Hello! I am just starting out on this four week journey and have just put together an iron mordant jar. While I wait for this to be prepared… I do have some ferrous sulfate powder available. I know this course focuses on the natural aspect of what can be found at home… But in looking online, it looks as though the recommendation is to use between 2-4% of weight of fabric to mordant for ferrous sulfate… is this what you would recommend as well? Thanks so much!
Hi Jess, sure you are very welcome to use the ferrous sulfate powder – after all, if it is something you have at home then that is perfect! Yes, use the recommended amount. I’m not fussy with the amount I use because with the homemade mordant it is impossible to know the strength, but with the powder you may as well measure it out.
Hi Marie, unfortunately not. But it is quite a forgiving substance so you don’t need to be exact with it. And the fabric will only absorb some of it from the mordant bath. If your fabric goes noticeably yellow, you have used too much, but otherwise it generally works out fine just doing it by eye.
34 Comments
Should the container the mordant is in be air tight?
Hi Erin, it shouldn’t matter in the short term, but in the long term it is better to have a well fitting lid, as this will slow the rate at which the vinegar changes pH. You want it to stay acidic, which is why I suggest topping it up with more vinegar each time you use it.
Okay, good to know. Thanks Louise!
Hi, do you add any water to the vinegar? or just vinegar and rusty bits. thank you.
No, I always do straight vinegar and iron. I have seen other people use water, but I’ve gotten far better results from vinegar especially while it is still fresh. Here’s an article I wrote about that.
Hello there!- just found some rusty bits yay! Just out of interest – what effect has the amount of iron being used? Like the more the more powerful it’ll be ( = using less of it ) – or maybe it could become say too strong? Topping up with vinegar is ok I read – can one also add new irony bits at a later stage and still use the mordant directly or would I have to wait a certain amount of time again?
This is already fun! Thanks a lot 🙂
Yes, when we use them in week 2 I’ll talk about how you need to use more if it is weak, or less if it is strong – but to a certain extent, the fabric will only absorb so much anyone, so it kind of regulates itself. Yes, you can keep adding more iron over time along with more vinegar – although even one piece of iron can last a long time, so you’ll find you won’t need to do it often!
perfect, thanks 🙂
The only vinegar I have is pickle onion vinegar…….can I use that?
Yep, I reckon it will still do something, even if not as good as white vinegar. A lovely example of making do with what you have.
I also make pottery and use iron oxide as a ceramic colorant. Could I use the powdered iron oxide as a mordant? I know this course is more about using everyday items, but I’ve had a hard time finding rusty metal around my house. Thanks!
Sure, give it a try! This course is about using what we have, so that’s perfect. It might be better to dissolve it in vinegar then add to the water when we use it in week 2, but I haven’t tried it myself so can’t say for certain.
OK, I’ll try it and let you know how it goes.
I made some iron mordant this time last year from your ebook Plant Poetry, haven’t used it for 6 months though its still in the jam jar i made it in, will it still be ok or should i start again?
I’d add some more vinegar and see how that goes. If you get pale results you might want to try again, but it will probably still work ok.
Hm, I can’t find white vinegar in any shops. I’m kind of surprised, there’s only distilled, white wine vinegar and malt. Any of these substitutes that might work best?
Hi, distilled vinegar is the most similar so is the best option, although probably any would be fine.
Should we rust our iron prior to adding it to the vinegar or can you add it in without rust?
Yes, you can put it in before it is rusty, it will just take a little longer than using rusty iron. But pre-rusting it yourself will also take time, so it’s easier to just put it in the vinegar as is.
How long do you need to leave it before you can start using it? I found a iron camp oven which was left outside and has gone really rusty so I’m just going to fill that up with vinegar. Also thankyou so much for this course xx
As soon as it changes colour, it can be used – you’ll need to use more if it is a pale colour, and less once it gets darker and stronger.
Just love your course – gentle clear teacher
So I started my iron mordant jar a year or so ago and recently topped up with fresh vinegar
It looks sooo potent ( almost dangerous)- the lid has rust crystals and it’s a thick almost syrup
It is in a glass jar- safe – shall I remove the rust things and dilute – disposing of half liquid ????
It’s a monster and possible far to strong…
I’m a bit behind the classes but hoping to work
( NBT) with parents who have no self time as their kids have Autism …. art teacher embracing nature
-Sally
Hi Sally, yes you could strain the metal out to stop it getting stronger. And then just use a very tiny amount to mordant with. If your fabric goes noticeably yellow, you will know that you have used too much, and can ‘flush’ the excess off by soaking in plain water.
Hello! I am just starting out on this four week journey and have just put together an iron mordant jar. While I wait for this to be prepared… I do have some ferrous sulfate powder available. I know this course focuses on the natural aspect of what can be found at home… But in looking online, it looks as though the recommendation is to use between 2-4% of weight of fabric to mordant for ferrous sulfate… is this what you would recommend as well? Thanks so much!
Hi Jess, sure you are very welcome to use the ferrous sulfate powder – after all, if it is something you have at home then that is perfect! Yes, use the recommended amount. I’m not fussy with the amount I use because with the homemade mordant it is impossible to know the strength, but with the powder you may as well measure it out.
hello Louise,
I was wondering if there was a way to know the concentration rate of the preparation ????
Hi Marie, unfortunately not. But it is quite a forgiving substance so you don’t need to be exact with it. And the fabric will only absorb some of it from the mordant bath. If your fabric goes noticeably yellow, you have used too much, but otherwise it generally works out fine just doing it by eye.
oops my fabric is totally orange … we’ll see… kiss from france
Hi, Slow student! Should I put the iron mordant through a coffee filter or something? It’s quite a mess and lots of rusty bits! Thank you!!!!!
Hi Linda, yes if the mordant is quite ‘chunky’ you can strain it through a coffee filter or fine fabric.
I just found this class and am so very grateful for your offering it for “pay what you can.” I could never have afforded it otherwise. Bless you!
So glad you were able to join us!
I never used mordant before. Very interesting to know about it!
Mordant is very important for getting good prints on cotton!