Soda Crystals and washing machines

Soda Crystals Soda crystals are reputed to be good at dissolving grease. They can be used to help clean out a gunged up washing machine, or more importantly to help prevent a build up of grease).

Can soda crystals damage the washing machine drum?

The last time I used some I noticed that on the back of the packet they say that it should not be used on aluminium. I instantly thought about the alloy drum spiders inside washing machines and wondered whether soda crystals could cause any damage.

Door-seal-greasy So I sent an e-mail to a manufacturer of soda crystals. They told me that there shouldn’t be anything to worry about. The only reason they advise against using the soda crystals on aluminium is that it can cause pitting (small indentations). This would be undesirable on anything on show. But as no one can see the drum spider it shouldn’t be a problem. I don’t think the soda crystals would undermine the strength or stability of something made of aluminium, just maybe cause small pitting.


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25 thoughts on “Soda Crystals and washing machines”

  1. Hi there,
    I have just done the ultimate test on our fairley new cold fill washing machine, my wife now and again spills curry on her white dressing gown we would put it in our zanussi washing machine and the stains would be gone but this new Hotpoint washing machine is total rubbish put the said article in last night with same washing liquid and there is still a stain on it put it in again by its self this morning and the stain is still there.Which goes to show hot and cold fill washing machines are the best do you know of any manufacterer that has any old stock left ?.

    Cheers Nigel

    1. Hello Nigel: I wouldn’t think this has anything to do with the hot and cold fill issue. If anything, a cold fill washing machine should wash better than a hot and cold fill. A cold fill washing machine takes longer to wash, which clearly helps, it also removes the possibility of some stains being “fixed” by coming into contact with hot water and if using biological detergent it’s been shown that they work much more efficiently by starting with cold water.

      A quick search on Google for “remove curry stains” indicates they are a very stubborn stain indeed and quick action is required as soon after the incident as possible.

  2. There are many variables involved in removing any type of stain which is why most folk will get varying results with similar stains and removal techniques. Some of these are- the strength of the stain (with curry- what was in it?), time the stain is left, the material stained, the size of the wash the stained article is washed in.

    My opinion with this particular issue is simply that your Zanussi washer had a more efficient wash cycle than your new Hotpoint, all other variables being roughly similar.

  3. I read with interest your comment on the use of soda crystals in the washing machine. My mother has a 10 year old hotpoint washer at the moment and it’s still going strong, and before that a tricity bendix which lasted for 22 years. (apologies for any miss spellings in the manufacturers names) Which she said took her three years to save up for. I think shes pulling my leg. For as long as I can remember she has never bought any biological washing powder or liquid, as she always makes her own.

    We both suffer from dermatitis and since I moved out 15 years ago she also makes mine. It consists of Borax substitute, Soda crystals, soap flakes and something else, i can’t remember. She has made some changes to the mixture over the years depending what she can get hold of. The 22 year old bendix was fed this concoction for its entire life and so is the hotpoint. I have a 8 year old bosch and I use it too. (must ask her how to make it actually as i’m suddenly feeling embarrassed that i get my mum to do it.) I have used shop bought powder occasionally if i’m waiting for my order from mother, but it doesn’t get my white sport socks white like the home made stuff.(I know, I know, I’ll ring her after I’ve written this and and get a crash course in washing powder making.)

    Also, Something went wrong with my machine about three years ago and the guy from bosch said “I see you use limescale remover” To which i said “No, and never have.” He said that it still looked brand new. No mold or greasy build up in the drum seals, so I was chuffed. Anyway. I was surprised to read your above article on the affects of soda crystals on the aluminum spider. Would we have not had any problems to this affect? I wash maybe 4 or 5 loads a week. and always with this home made concoction. Just thought you might find it of interest.

  4. Darryl, if you manage to get the formula for mom’s washing powder, perhaps you would be kind enough to publish it here. It sounds like the bussiness! Unless it’s a trade secret!

    I know soda crystals are good for your machine- I’ve used them for years with no ill effect. I suspect manufcturers advise against it because they want you to buy the expensive water softeners they recommend and must have an interest in.

  5. Hi Paul.

    Sorry for the delay. Have managed to get ingredients for the home made washing powder and it’s dead easy.

    Best to have one of those plastic cereal box containers with a flip air tight lid to store and mix it all up in.

    The recipe below includes oxygen bleach powder. I have two powder mixes made up at any one time. One for the whites, which includes the oxygen bleach powder, and one for darks and bright colours, which doesn’t. This is the only difference between the two powders.

    You will need.

    1KG box of Soda crystals (washing soda in the U.S.)
    500g box of Borax Substitute (think you can still get original borax in the U.S)
    2 Tablespoons of Soap flakes.
    2 Tablespoons of boxed oxygen bleach (for whites)

    Pour it all in the container and give it a good shake. Use half a cupful in each wash, depending on the drum size. I find half a cup is fine for a 6KG drum. I personally chuck it in the drum on top of the clothes and not in the washer draw as is leaves a residue in it.

    All of the above Mum can get in the supermarket. If you can’t, I found all of it online. Buying in bulk makes it cheaper. One batch works out at about 6 or 7p a wash.

    Unlike Shop bought detergents this recipe has no smell. I find that i don’t need to use fabric conditioner either because the mixture of the soda crystals and the borax makes the water so soft your clothes feel great when there done. In fact i used to use fabric conditioner but it just left a residue of the clothes. So to make thing smell nice, if your putting your washing in a tumble dryer, put two or three drops of essential oil (any fragrance you like) on a cloth or duster and add it to tumble. It is quite strong smelling so do some tests first with maybe 1 or 2 drops. The smell also lasts until you next wash it. Bonus!

    If your not tumbling or you want extra strong smell. Mum said that she puts a couple of drops of essential oil in a spray bottle to dampen the clothes before ironing. (Ironing! what’s ironing?)

    Hope this helps anybody that has sensitive skin or any medical conditions like me and just can’t use shop bought non-bio powders. Oh! you’ll never have to worry about stains ever again. This sucker will shift anything!!!

    1. Hi, Darryl,
      I’ve just discovered this thread, and am desperately seeking a new approach to laundry, as I am fed up with my clothes smelling stale after a week or two in the wardrobe.
      Your home-made recipe sounds great, and I’m going to give it a try (maybe you should patent it!); just one question on quantity – do you mean 4oz – half-a-cup American measure?
      Many thanks

  6. Thanks, Darryl Will get some made up. My daughter has a part time job at MacDonalds and you just cannot shift the grease stains from the uniform. I t will be an interesting test, since Vanish doesn’t shift them.

  7. Many posts on many sites claim that the corrosion of the spiders is due to galvanic action. I do not agree, I believe it is primarily chemical corrosion.

    Should the corrosion have been galvanic between the stainless steel drum and the aluminium spider the majority of the corrosion would have been at the junction of the two metals i.e. at the ends of the arms. I have seen no photographs of spiders corroded in such a manner, nor read of any similar descriptions.

    Aluminium is corroded when immersed in an aqueous solution with a pH value above about 8.0. All detergents have to be above about 8.0 or they would not work. The Material Safety Data Sheets (MSDS) put out by Proctor and Gamble state that the pH for one of the liquid Tides is 8.0 and for one of the Tide powdered detergents as 11.0. Bleach, (sodium hypochlorite) is also very corrosive to aluminium. I should add that for corrosion of the spider to take place these levels are considerably above the levels found in a washing machine during the wash/rinse phases of the cycle.

    Sodium carbonate (washing soda)and sodium percarbonate found in some laundry aids are also corrosive to aluminium, provided the required concentrations are reached.

    I believe the mechanics of the corrosion are as follows.
    Even after the fastest spin small quantities of water will remain on the shaft and towards the centre of the spider. Any recesses in the spider close to the centre will aggravate this situation. This water will contain very, very small quantities of laundry aids used, soil from the laundry and chemicals from the tap water. Should this water be allowed to stand the water will evaporate until such time as sufficient has gone to allow the pH of the remaining mixture to rise above the threshold at which corrosion will occur.

    Additionally the retained water will quickly become foul smelling leading to, I believe, many of the complaints about mold and mildew.

    The first MSDS I found on the web for sodium carbonate gave its pH for a 1.0% solution as 11.5 I.e very corrosive to aluminium.

  8. As a follow up to the above post, should you be interested in seeing what corrosion can do to aluminium spiders please visit ‘ I hardly need add that I wrote the piece at the end of that post disagreeing with the suggestion that it was due to galvanic corrosion.

  9. Thanks David: I agree that the cause of this phenomena is unlikely to be related to a clash of metal. I think it’s related to the detergents and/or a build up of grease and slime, which eats away at the alloy. I’ve seen many of them in this state and they always corrode in the same place and are always caked in slime and grease and white detergent.

    I’ve seen many without any slime or grease though and just a thin crack in one or more of the arms. Maybe they have a tendency to crack, and that allows the corrosion to take hold if the environment is bad enough.

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