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Removing thinset from inside bathtub

caseyr | Posted in Construction Techniques on February 29, 2008 06:38am

Just had new tile laid on the bathroom floor. The installer did a good job but his helper apparently cleaned his tools in the bathtub and left a large mass of thinset or mortar in the bathtub. Unfortunately, I did not find it until the next day. I was able to remove about 90% of the stuff, but there is a large gray spot about a foot in diameter and an area about half that size with pronounced black streaks. I think the stuff was modified thinset.

I did a web search, but got lots of sites that tell me how to remove grout from around the tub when removing the bathtub – but nothing on getting the stuff off the bathtub when it is spilled inside.

I have some Bon Ami that I am about to try, but I would assume that even Bon Ami is likely to remove the sheen from the porcelain if I scrub too long and hard. Anyone have any magic pixie dust to make this stuff go away?

The guy behind the counter at the tile shop suggested trying X-14 cleaner, which I will try and locate. I have my doubts, however, that it will do much good. Probably try some strong oxidizing cleaner to ee if that will at least lighten the dark gray areas.

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Replies

  1. JerryHill | Feb 29, 2008 06:52am | #1

    C.R.L. Cleaner?  I'm surprised that the tub even drains now!

  2. seajai | Feb 29, 2008 07:13am | #2

    http://barkeepersfriend.com/stains.html  Removes all kinds of stains. It works great and won't damage your tub.

     

    1. User avater
      xxPaulCPxx | Feb 29, 2008 07:38am | #3

      You need to break the bond that is assisted by latex first.

      Look at Goof-Off products by the paint strippers and cleaners.

       

      EDIT - Actually, you need to call numbnuts and his boss back to the house FIRST before you do anything else.  They fix it or... or they fix it.

       

       

      Rebuilding my home in Cypress, CA

      Also a CRX fanatic!

      If your hair looks funny, it's because God likes to scratch his nuts.  You nut, you.

      Edited 2/28/2008 11:39 pm by xxPaulCPxx

      1. caseyr | Feb 29, 2008 08:09am | #4

        Being deaf and depending upon email for communication tends to slow response considerably. I did sent an email yesterday, so we shall see what response is forthcoming. I will give both the Bartenders Friend (I have some stored away somewhere) and the Goof-off (I think there are supposed to be two versions of Goof-Off, but I have the most commonly available one). Not sure what order to try them. Hopefully they will not, in combination, dissolve not only the grout but my bathtub as well...

        1. dovetail97128 | Feb 29, 2008 08:40am | #5

          ""Hopefully they will not, in combination"" BE CAREFUL and READ the ingredients. Combining any number of household cleaners and spot removers can cause dangerous gases to be formed. Best to use one product , rinse well, rinse again and then apply the second product if you have any doubts about interactions between products.
          They can't get your Goat if you don't tell them where it is hidden.

        2. rlrefalo | Feb 29, 2008 04:43pm | #10

             Casey try denatured alcohol to cut the latex modifier. Again use a rag to keep it wet for a while.

          1. User avater
            IMERC | Feb 29, 2008 04:45pm | #11

            and air dry the rag before ya toss it... 

            Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->

            WOW!!! What a Ride!Forget the primal scream, just ROAR!!!

    2. IdahoDon | Mar 02, 2008 06:25am | #21

      An ex of mine used to be a professional new construction cleaner.  That's the stuff she used. 

      I've also had good luck with mild acids like vinegar, since it eats the sand and cement making the synthetic portion easier to remove. 

      Beer was created so carpenters wouldn't rule the world.

  3. splintergroupie | Feb 29, 2008 08:58am | #6

    I would first try an acidic substance like white vinegar. Put a rag on top to hold the vinegar on and keep it wet for awhile. The acid should help break up the mortar. I've cleaned tools like this that sat too long.

    If you want to kick it up a notch, there's muriatic acid, but i'm not sure what it would do to your tub.

    http://www.naturalhandyman.com/iip/infxtra/infmur.html

  4. User avater
    observer | Feb 29, 2008 09:32am | #7

    Muriatic acid should do it. Keep it wet and let it soak in. Repeat. Scour with a plastic scouring pad.

  5. deafbob | Feb 29, 2008 09:49am | #8

    i agree, this isn't your problem. allow them to make it right. if they refuse document. then maybe you try. if you jump gun with out allowing them to formally refusekk , you may relieve them their liablilty.

  6. Danno | Feb 29, 2008 04:03pm | #9

    I would be careful with muriatic (hydrochloric) acid as it may etch the tub. Vinegar may work, but anything that will attack thinset will probably also attack the porcelain finish on the tub. Goof-Off sounds like a good idea too. Or alcohol. As always, start with what wil be the least harmful to the tub finish and go stronger if necessary. The solvents like Goof-Off and alcohol are the least likely to attack the tub, but even vinegar may etch the surface if left on too long.

  7. cargin | Feb 29, 2008 04:50pm | #12

    CaseyR

    I would agree that the tile setters are responsible for replacing your tub.

    If that's not possible then I would look for a tile of tub cleaning product that has phosporic acid in it. It is mild enough that it won't eat your finish.

    Phosporic acid is the ingredient in naval jelly. You can use it straight or thin it with water. Warm water makes it work better. Let it sit on the spot for a time before trying to scrub.

    If you know a Conklin dealer then get some Multipurpose Surface Cleaning Gel.

    Our plumbing retail outlet (Handyman) carries a similar Phosporic acid based cleaner but I don't have a bottle around right now.

    If the product is made to clean toilets then it is too strong and stay away.

    I don't think you mentioned if it is a cast tub or acrylic.

    If it is acrylic I would be careful with the solvents. I burned a tub surround with either Goof Off or Goo Gone, can't remember which it was now. Not a pleasant experience.

    Good luck.

    Rich

    1. caseyr | Feb 29, 2008 11:05pm | #13

      I tried the Bartender's Friend and it worked amazingly well. I didn't even try the Goof-Off. I think the Bartender's Friend is probably even less abrasive than Bon Ami, but it works. Got it at the local Target store but the website for the stuff said it was also available at Safeway and Albertson's. I had heard good things about it, but this was the first time I ever actually put it to the test.

      1. rjgogo | Mar 01, 2008 01:21am | #14

        Barkeepers Friend is more aggressive  then Bon Ami.  Bon Ami wont scratch Stainless steel, Barkeepers friend will although very very fine scratches.  So don't use it on a Range hood,  Neither will scratch porcelain.  That is what I found when cleaning baked on stuff off my SS range. 

      2. rasconc | Mar 01, 2008 03:33am | #17

        There is a liquid version also sold as a stainless steel sink product.  Both rock.

        edit: used to be called shiny sinks plus

        http://barkeepersfriend.com/products.htm

        Edited 2/29/2008 7:36 pm ET by rasconc

      3. User avater
        BillHartmann | Mar 01, 2008 03:46am | #18

        BTW, BKF has oxcialic acid in it. Great for stains.Until you posted this I would not think that it would be that good on grout.BTW if you have some that still can't get off, check the grout manufacture. They have a grout haze remover which is acid based. But I don't know which acid off hand..
        .
        A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.

        1. TheTileDon | Mar 01, 2008 08:52am | #19

          I had a great experience with BKF.  After flushing out the plumbing lines into the tub, little specks or stains were left from metal pieces.  BKF took them right out.

        2. caseyr | Mar 02, 2008 04:42am | #20

          Bill -
          I asked about the acid based tile cleaner at the tile shop and they said that it would take the sheen off the porcelain of the tub, so I ruled that out.

  8. MSA1 | Mar 01, 2008 02:25am | #15

    Why do people write about what other people did? Thats not your problem. I'd say the best way to get the thinset off of the tub would be withholding the check, sit back and watch the thinset disappear.

  9. sledgehammer | Mar 01, 2008 03:19am | #16

    I'd be more worried about the thinset in the trap and drain pipes..... How do you remove that?

  10. WayneL5 | Mar 02, 2008 06:40am | #22

    Vinegar.  Let it soak a long time.

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