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Best pipe dope for large threads

Ron Jr.Ron Jr. Member Posts: 527
Started a big job today . 9 section Burnham V9 steamer . We have a ton of 4 inch pipe and fittings to install , and a good amount of 6 inch .

We've used Teflon and Rectorseal in the past ( inner and outer threads with the Rectorseal ) with mixed results .

Can anyone recommend a sealant that will work the first time around ?

Thanks in advance .


  • meplumbermeplumber Member Posts: 678
    Blue Magic/Blue Monster


    I was a Rectorseal guy for years too.  About a year or so ago, I started using Blue Magic Industrial Grade pipe dope by Whitlam with Blue Monster Tape made by Mill Rose.  Huge difference.  Not sure what the "Blue" difference is but together they work.  It is my only combination when I absolutely have to have it not leak the first time.

    Good Luck.
  • RobertRobert Member Posts: 139

    I have had good luck with Gasoilia pipe dope + teflon tape on my applications, but recently I installed a 50's coal boiler that had some rough looking threads on some of the boiler tappings.  My local supply house recommend a pipe dope called "GRRIP" with teflon tape.  This pipe dope looks like coal tar, it is black...and it refuses to come off anything it touches.  I put two wraps of teflon tape on the male threads, a libral amount of dope, and also some dope on the female threads.  It has been pressurized for a week with no leaks!

    My only concern with this pipe dope is future removal of the seems to set up pretty well.

  • Patchogue PhilPatchogue Phil Member Posts: 263
    plumbers twine?

    Does anyone use plumbers twine in large threads anymore?

    Someone recommended Grrrip to me.  Worked great on a connection that just wouldn't stop dripping with tape,  white dope or both.  Never tried to take anything apart with Grrrip.  Definitely nasty sticky.  You have to wear gloves just looking at the bottle.
  • billbill Member Posts: 429
    The blue stuff

    As previously mentioned, what is the deal with the blue stuff? This stuff is magic! We just did a couple hundred joints with the tape.  We would go at a fitting or pipe with three foot wrenches and the joint would seem to loosen after a while. But best of all, no leaks!
  • Charlie from wmassCharlie from wmass Member Posts: 3,923
    Still a fan of plain pipe Dope

    I have tried many things but the plain grey pipe dope is my go to. It comes in quarts not just the little plastic bottles.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • JohnNYJohnNY Member Posts: 1,823
    We still use....

    wick and Pro Dope for all our steam and water-carrying pipe.

    My brother DESPISES teflon tape. Says it makes us look like DIYers, and so we've carried on dad's traditions to the current day.

    My opinion is it's still the way to go.
    For private consulting services, find John "JohnNY" Cataneo here at :
    "72°F, LLC"
    Or email John at [email protected]
    Or at Gateway Plumbing & Heating
    John travels regularly to out-of-state clients for consulting work.
  • Ron Jr.Ron Jr. Member Posts: 527
    edited November 2010
    Thanks guys

    for the advice on sealants .

    We got further than we thought we would on the 2nd day . That's Kenny is the 1st pic . 9 section Peerless coming out . 9 section Burnham going in . BIG house on one of the last true estates on the Gold Coast of Long Island , in Lattingtown .

    Had to use what was on hand ...................  Teflon paste , Rectorseal and Pro-Dope . I'll let you know if any of them leak .................. 
  • Big EdBig Ed Member Posts: 869
    I hate Leaks

    You heard this before ... Lamp wick , plumbers twine , what you ask for is quick wick,,, Right now using Prodope with it ... Since I went back to Quick wick years ago I had very few thread leaks. But with large pipes drag out them big wrenches. The ones in the corner of the shop. Do you know you should only show two to three threads ?? Also putting pipe dope on the female threads are against code ?? Don't do it not needed , besides gums up the iner works... Coats probes and sensors. Which we have a lot of now. Hang up the Teflon for iron and brass threads. May use on changeable parts.

    Every leak costs a extra hour at least.
    I have enough experience to know , that I dont know it all
  • Charlie from wmassCharlie from wmass Member Posts: 3,923
    Looks good

    I must be nice having a boiler room you can swing a wrench in. Are those zone valves on the supply piping in the first picture?
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • Ron Jr.Ron Jr. Member Posts: 527
    That's the first time

    I've heard that doping the female threads is against code ..........  Which code is that ? I know it says it right on the Rectorseal can ............. " For larger threads , use sealant on male and female threads " .

    Alls I know is I hate leaks just as much as you . Re-doping one of those 6 by 4 tees would be a profit killer . So we painted every thread we seen :) And believe me , it is needed . Past experience and all that . As far as the dope getting into the inner workings  ......... not an issue if you do the right thing and skim and purge . A necessity on any new steam boiler    I'll let you know tomorrow or Friday what happens when we get 'er running .
  • Ron Jr.Ron Jr. Member Posts: 527
    Thanks Charlie

    This one is actually in a pit . But plenty of room to swing even the 5 foot wrench we got . There's Kenny taking a seudo-break . Just me and him for day 3 .
  • Mark EathertonMark Eatherton Member Posts: 5,584
    Kenny looks STOKED ....

    Sorry, couldn't pass that one up..

    Amazing as usual.

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Big EdBig Ed Member Posts: 869
    edited November 2010

    I was surprised too after reading of it in the New York State code book... but it makes sense,where is all that goo going but in the system . Pipe dope is used as a lubricant to make up tapered threads .. The tapered treads are meant to be tighten and lock in . A good plumber would tighten the connection to the last two threads ..That is where a proper size pipe wrench is used.. Sure Pipe dope and quick wick helps fill in the imperfections .. Teflon I feel is too tough and and does not give away , it also expands the thread size where you can not tighten as much as using pipe dope ..

    NY code supersedes the rector seal company .

    Why wait for the skimming , if even if the stuff even floats ? I like to soak my treads and fitting with detergent and water before installing . Makes skimming a lot less pain full ..
    I have enough experience to know , that I dont know it all
  • Ron Jr.Ron Jr. Member Posts: 527
    edited November 2010
    NYS code ?

    Can you tell me the exact wording , Big Ed ? Cause to tell you the truth I really have a hard time believing that . If for some reason a code official deemed it necessary to open a system and look at what's on the inner threads ................... after the first steaming all evidence would be missing .

    But besides that , I could not fathom installing 2 - 6 by 2 ells , 4 - 6 by 4 tees , 9 - 4 inch ells , 3 - 4 inch unions and some assorted 3 inch fittings ..........  without using sealant on every threaded surface . As it was , with all those fittings we used less than 2 - 16 oz cans of Teflon sealant . The majority of that is permamnently in the mated surfaces of the fittings . Whatever might have oozed out is NOTHING in comparison to all the impurities that are in each new boiler section and what's left over in the old system .

    As far as soaping down each fitting before installation .............. that's all well and good if you built in the extra time to do that . Personally I've had no problem installing them as is and utilizing the skim and purge process to clean the system as a whole . 

    You state a good plumber would tighten the connections to the last 2 threads . What about nipples that have more threads than others ? And I've heard the " sealant is a lubricant " phrase quite a few times . But if it really is a lubricant , why don't we use motor oil to tighten fittings in ? WD-40 ? Maybe the same dish soap you use to clean the fittings out .......... ?  A thread sealant does both lubricate AND seal joints .
  • Ron Jr.Ron Jr. Member Posts: 527
    Thanks Charlie

    Yep , there were 2 - 4 inch zone valves and 5 - smaller zone valves with a mix of 2 inch to 1 1/2 .
  • Ron Jr.Ron Jr. Member Posts: 527
    Hey Mark

    He was stoked but good ........

    We actually had this ready to fire on Thursday . But the oil burner wasn't working right . The cam control for the low / hi fire baffle was busted .

    Got it running Friday but needed more burner tweaking befre I left for the Big Ugly . Kenny told me he flushed the returns and skimmed the boiler . Only took 2 hours to get the whole system clean . Extra sealant and all :)

    And the best part .................. NO LEAKS !  Which was a great  " whew " for us .
  • SnapdaddySnapdaddy Member Posts: 2
    Best I've found....

    for anything bigger than 2".......1/8" 5P - 6010!!!   haha - couldn't resist!
  • GREENMANGREENMAN Member Posts: 25

  • Charlie from wmassCharlie from wmass Member Posts: 3,923
    As for female threads and doping

    I was always taught to only treat the male threads. The only time I have seen a call for female threads to be treated is when trying to make Straight threads on European boilers seal to tapered american pipe and fittings. I am sure your skimming takes care of your systems, just something you do different. Try a few easy joints with out doping the female threads and see how it goes. You may cut your sealant budget in half and save money on skimming. Just a thought.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
  • bobbob Member Posts: 813

    you can hang your hat on 5P you'd better hide it with a round of 7018. ; > )
  • jonny88jonny88 Member Posts: 1,139
    hercules pro dope (yellow can)

    just finished running 200' of 3" blk pipe.we used pro dope only,no wick or teflon needed.make 9 threads on your pieces and you will be fine.good luck,

    My local plumbing supply house also recommended Grripp. Wear gloves, it needs solvents to clean up. But am very happy with it. And, in fact, I had to undo it after two weeks and add a new bit of pipe. Trick is to heat it up -- when cold, it's hard like steel. When hot, it gets soft and can be undone. This is the info on Grrip from Hercules (scroll down to Grrip) . . .
  • Ron Jr.Ron Jr. Member Posts: 527
    I've used Grip before

    but for the life of me I forget what it looks like or how it spreads onto the threads . I'll take a look at the link .

    The Hercules Teflon paste held up the whole season so far . A serviceman went back last week ( zone valve bypassing ) . Said all the joints are leak free . That'll be my go to selant for all larger threads . Thanks James for the link  .
  • MikeyBMikeyB Member Posts: 696

    I believe its in the light green container, black in color, hard to clean up, like Blue Block
  • Alan (California Radiant) ForbesAlan (California Radiant) Forbes Member Posts: 1,266
    edited February 2011
    Super Dope

    I found this sealant when first installing European boilers and radiators for their non-tapered threaded connections.  I use it now for any threads that are doubtful.

    I can hand-tighten pressurized connections without leaks.

    Edit: Nice Work, Ron.  "Keep 'em steamin'".

    Often wrong, never in doubt.
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