PVC primer/cement not hardening

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by suffer1034, Sep 23, 2012.

  1. suffer1034

    suffer1034 New Member

    Messages:
    3
    So I replaced a PVC closet flange yesterday. Today I wanted to make sure the joints were hardened before putting the toilet back on. So I was gently pushing on the excess primer/cement near the joints with a small screwdriver to make sure they were hardened.

    Its tough to tell in most spots, but where ever I got a bit of excess I could tell that I can easily push on this excess with the screwdriver. I was expecting it to be rock hard.

    I used a standard purple primer with a general purpose schedule 40/80 cement. Note that my PVC is schedule 30 (which I understand is just thin wall schedule 40).

    Am I doing something wrong? Its been 24 hours now.
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    Location:
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    The cement, as opposed to a glue, actually is a mix of solvents and pvc disolved in it. It literally melts the pipe and fitting and has a little extra body to fill in. It doesn't resolidify until all of the solvents have evaporated. My guess is that you couldn't pull the joint apart. It should be fine. Try not to use excessive amounts.
  3. suffer1034

    suffer1034 New Member

    Messages:
    3
    I gave it a decent tug and couldn't budge them.

    Great info thanks. That's a load off my mind...and hopefully one soon through my new flange.
  4. hj

    hj Moderator & Master Plumber Staff Member

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    Sch. 30 pipe has an "actual i.d. of 3.0", which it has to have to maintain a smooth bore if used with ANY other DWV material. BUT, it has an o.d. of 3.25", which is too small to fit any sch. 40 or 80 fittings. It ONLY fits sch. 30 fittings which are not compatible with any other grade. That being the case, HOW did you attach a flange to the pipe and get any kind of proper connection.
  5. suffer1034

    suffer1034 New Member

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    3
    Originally - The schedule 30 pipe goes into a 90 elbow. They had a flange to exact fit the elbow.

    New one I installed. - I cut off the elbow, then I added two 45 elbows instead of a 90, to create a longer sweep. There was a special flange at Lowe's to fit into the 2nd elbow around the outside of the elbow. Fit perfectly.

    Edit: I'll add, most of the flange's at Lowe's would not fit (probably because they were for schedule 40 pipe).
    http://www.lowes.com/pd_104527-322-...e&utm_source=AskAndAnswer&utm_content=Default
    Last edited by a moderator: Sep 23, 2012
  6. Tom Sawyer

    Tom Sawyer In the Trades

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    My head aches :confused:
  7. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,360
    Location:
    New England
    IF you tried to dry fit things, and made your choice on that, that's where you went off the bandwagon! The fittings are an interference, tapered fit...the pipe only fits fully into the socket after you apply the cement and it melts the material.
  8. DonL

    DonL Jack of all trades Master of one

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    I fell off my rocker, don't feel bad.
  9. kreemoweet

    kreemoweet Member

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    ?They let you use schedule 30 pipe for house drainage piping in Michigan?
  10. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
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    Location:
    Cave Creek, Arizona
    It is usually used outside the building underground. The O.D. of a fitting is the same as the O.D. of sch. 40 pipe, which is why the flange fit over the elbow, but it was NOT, a proper connection according to the wording of the code. To use sch. 30, or S&D, pipe indoors you would either have to find sch. 30 fittings which are limited, or use 40x30 bushings into every fitting.
  11. BobL43

    BobL43 DIY Senior Member

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    Don, quick! get back on that rocker. We don't want to be off our rocker, do we?
  12. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
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    Location:
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    quote; We don't want to be off our rocker, do we?

    Given the quality of some of the recent posted replies, I think it is too late for some people.

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