Removing watermarks (I think) from sapelle

seannash

Hi, I have an old school lab countertop which I've began sanding. I've encountered some marks and I'm not sure how to get rid of them.
Any advice would be appreciated.

magicbastarder

if they came from a lab, there's a good chance that's not water - could be chemical or oil stains?

seannash

magicbastarder wrote: »

if they came from a lab, there's a good chance that's not water - could be chemical or oil stains?

Your right!!
Could definitely be something other than water. Any advice?. I tried sanding but they are deep

dathi

https://www.ebay.co.uk/itm/500g-Oxalic-acid-Hull-Deck-GRP-Cleaner-rust-remover/140426948733?epid=1125002887&hash=item20b219307d:g:OeYAAOSwrklVACWE:rk:2:pf:1&frcectupt=true


looks more like iroko than sapelle you can use oxalic acid to remove the stains from timber you mix about two teaspoons in 500mls boiling water and brush it on leave to dry or use heat gun to dry quicker may take several goes to remove stain rinse the wood well with clean water after . make sure you are using rubber gloves and mask as it is toxic

seannash

dathi wrote: »

https://www.ebay.co.uk/itm/500g-Oxalic-acid-Hull-Deck-GRP-Cleaner-rust-remover/140426948733?epid=1125002887&hash=item20b219307d:g:OeYAAOSwrklVACWE:rk:2:pf:1&frcectupt=true


looks more like iroko than sapelle you can use oxalic acid to remove the stains from timber you mix about two teaspoons in 500mls boiling water and brush it on leave to dry or use heat gun to dry quicker may take several goes to remove stain rinse the wood well with clean water after . make sure you are using rubber gloves and mask as it is toxic

Thanks for that, I'll give that a go.
And your right it could be Iroko alright. I was told it was either that or sapelle but as it had a dark stain on it I couldn't tell.

recipio

Pour some meths on them and set them alight. If they are oil based they will burn off. Otherwise oxalic acid is effective, especially on ink stains.

kadman

Head the warning on Oxalic Acid, its a deadly poison,

https://medlineplus.gov/ency/article/002479.htm

Poisonous Ingredient

Oxalic acid
Where Found

Oxalic acid may be found in some:

Anti-rust products
Bleaches
Metal cleaners
Rhubarb leaves

Note: This list may not be all inclusive.
Symptoms

Symptoms of oxalic acid poisoning include:

Abdominal pain
Burns and blisters where the acid contacted the skin, lips, tongue, and gums
Collapse
Convulsions
Mouth pain
Shock
Throat pain
Tremors (unintentional trembling)
Vomiting

Home Care

Seek immediate medical help. DO NOT make a person throw up unless told to do so by Poison Control or a health care professional.

If the chemical was swallowed, immediately give the person water or milk, unless instructed otherwise by a health care provider. DO NOT give water or milk if the person is having symptoms (such as vomiting, convulsions, or a decreased level of alertness) that make it hard to swallow.
Before Calling Emergency

The following information is helpful for emergency assistance:

Person's age, weight, and condition
Name of the product (ingredients and strengths, if known)
Time it was swallowed
Amount swallowed

However, DO NOT delay calling for help if this information is not immediately available.
Poison Control

magicbastarder

the acid in rhubarb is oxalic acid, maybe rub some rhubarb on it?

Esel

magicbastarder wrote: »

the acid in rhubarb is oxalic acid, maybe rub some rhubarb on it?

I know you meant rhubarb leaf.

seannash

Thanks everyone for the replies. I've ordered some oxalic acid so hopefully that will shift the stain.
Perhaps he can help me with something else.
I've sanded down the countertop but I feel I've hit a wall where it won't sand anymore unless I apply a good bit of pressure.
I'm fearful I'm digging in too much.
Can I ask if from these pictures you can tell if I'm back to bare wood or if I've a way to go.