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threaded fittings

The threaded joints seal on the peaks and valleys, not on the slopes, for a couple of decades now we've been softly sanding them both. Key word-softly. To much and the joint bottoms and nothing short of JB weld will fix it. Brass joints are always sanded but very very very softly. Ten times around will teflon tape on three-quarter and smaller, a good teflon dope on larger. While watching a machinist turn a piece, he would hit his work with emory cloth, I asked him why after he had cut the material on a lathe, he told me it doesn't cut, it tears. I had been tearing threads? Feel the threads, before and after sanding, burlap then silk. Dad told me, especially on brass joints in the olden days, they would dope the the male then fill the threads with sewing thread. Remember that gray, nasty pipe dope?

Comments

  • threaded ftgs

    is it my imagination, or are threaded ftgs not made to very close tolerances anymore? foreign?
    when i first started plumbing in '70, we did complete apt complexes without any where near the leaks that i see today. and i'm tempted to follow the lead of some of the younger pipers who use teflon AND dope. and when i told my bro-in-law, old school, retired plumber from way back, he just laughed and said; 'they must not feel very confident in their work'. but i'm starting to wonder.........
  • Rich Kontny_3
    Rich Kontny_3 Member Posts: 562
    Not Your Imagination

    Due to globalization we have PVF materials that are all over the tolerance charts (large small and indifferent!)

    A very big problem that hopefully forces us to use domestic sources once again!
  • yea,

    I had a fitting just a while back I buried the pipe into and it still would not stop leaking. Pain in the you no what, used up a lot of time a simple thing like that shouldn't. Didn't pay attention to the country of origin, probably China or Thailand. Not a big fan of doubling up the teflon and dope but any port in a storm guess.
  • Not Round

    The pipe and fittings coming from China are not very round, and the pipe is soft and threads poorly.

    The stuff coming from Canada was pretty good, but has gotten worse.

    The US made stuff is OK, if you can get it, but we order our pipe unthreaded. If it comes pre-threaded with couplings all on one end, and banded together, it's likely to arrive bent.

    We do a lot of process piping jobs where I work, 1 1/2 and 2" pipe mostly in the threaded sizes. We used to use four wraps of Teflon tape per joint, and never had leaks. The standard has become seven wraps of Teflon tape, then Loctite pipe sealant. It sounds nuts, but without it there are just too many leaks.

    Isn't globalization wonderful?
  • Joe Billow_6
    Joe Billow_6 Member Posts: 69


    Ever notice that the elbows seem to be off of 90*? I had a few really bad WARD 90s that seemed about 95s
  • Sigh,,,

    Why does a job flipping burgers keep looking better and better? ;)
  • mtfallsmikey
    mtfallsmikey Member Posts: 765
    I still have

    Some old Grinnell U.S. made fittings in my stash...maybe worth a fortune on Flea-Bay?
  • Timco
    Timco Member Posts: 3,040


    I had a Tee last week used on a LWCO for a steamer, and it needed to be straight, but was not and my union would not line up. I got turned onto hemp for threaded ftgs and it works very well. Better than I thought it would. Not a single drip with it, but it kinda smells and can be a mess if you do not develop a method to application. ( BIG shoutout to Clif Heeney!! Thanks for the cross-pond hook-up!!!)

    Tim
    Just a guy running some pipes.
  • oil-2-4-6-gas
    oil-2-4-6-gas Member Posts: 641


    you should try some of the 1" and 1-1/4 cross tees although for years now the've been way off
  • Getting MUCH worse

    I pride myself on BI/Steel pipefitting, but this junk makes most look bad. Pipefitting allowances are out the window.
    Dies wont start, or fittings screw to the bottom & still leak!
    Is this free-trade?

    Dave
  • hemp?

    what are ya, some kinda hippie?
    don't bogart it. tell me about hemp
  • Timco
    Timco Member Posts: 3,040


    When the leaks get you too upset, just pack a little into a 'pipe'...kidding.

    It looks like horse tail hair, and you put a bit of 'dope' on the threads then fill the lands with fibre, then a bit more 'dope' and assemble. Works great and I can make up 'joints' fairly cleanly now...

    Tim
    Just a guy running some pipes.
  • Sounds like

    you are describing oakum Tim,, but that is made of jute fibers & pine tar if I recollect properly.

    Dave
  • yeah, 'ol grampappy oakum

    i miss packin 'n pourin stinky 'ol oakum

    and so far, i'm fast becomming a pink t-tape advocate. but i'll give the wick a try on the next threads
  • mark_121
    mark_121 Member Posts: 7
    It's not just the fittings

    Foreign nipples have gotten just as bad. The threads are not cut straight. but there maybe a fix to the fittings.
    Order from your suppler DOMESTIC ONLY they should be able to accommodate your request. Or just do business with some one else.
  • gray, nasty pipe dope?

    awww, we used to put that on our cheerios

    10 wraps of p-tape?!

    i'll have to try the thread 'buffing'
  • Chris Kuzila
    Chris Kuzila Member Posts: 11
    Breakfast of Champions

    I heard talk of Budweiser on corn flakes, no the dope was gray, gray like the soil around a pipe leaking natural gas, gray and odoriferous, then mixed with linseed oil or similar, we had to mix the stuff out of it in order to brush it. Dried hard. Ahh the olden days. Buff ones joints gently.
  • bob young
    bob young Member Posts: 2,177
    lampwick[quickwick] is the key

    lampwick is the answer to leakproof jointson water piping. gas is another story. ----permatex
  • Couderay
    Couderay Member Posts: 314
    Bud and corn

    Ah back in the days of hobart welding school kept trim with the breakfast of champions yep budweiser and corn flakes. My God someone else actually eats this stuff its amaizing what you will eat when broke. That dope your talking about is expando when hard the only way to get the fittings apart is with two 36" rigids and a heat up with the torch.
  • bob young
    bob young Member Posts: 2,177
    ever try litharge & glycerin ?

  • Big Ed_4
    Big Ed_4 Member Posts: 3,015
    Quick wick, pipe dope and tight

    Old school was Lamp wick pulled in single strand and pipe dope and tighten down to the last two or three threads. Then quickwick came to us so we did not have to pull apart the lamp wick for threaded pipe. And

    Need to find the right pipe dope. For me now it's a soft set Pro Dope for heating pipe. I feel soft set is better for thermal expantion on joints.

    I would never reuse a fitting. If a new fitting leaked get rid of it ..

    I remember as a kid the old guys bitched about the supply of fittings back then . I go back to the 70's . Hay they sell them by the pound !
    I thing the key is proper tighten of the work . Iron fittins and pipe 101 - Tighten down to last few threads. Cast is a different story, I am sure we all have one.....

    For me Teflon tape work is too loose . The stuff is great if you want take it apart years from now. Most of my work I want it their for ever so I only use it on parts like extrol tanks ....

    There was an error rendering this rich post.

  • Remember

    the old "red-lead", or the "graphite paste" used for push nipples.
    Doubt you could find it now.
    I wire-wheel every thread,,, sometimes use the 300 to tighten and they still often leak,, gets frustrating when taught unions should be used sparingly.
    Twisted a bushing in 2 Friday with a 10", AARRGGHHH,,,,

    Dave
  • here's some informal science

    put two wraps of pink p-tape on a piece of pipe, thread it into a fitting to the 'standard' depth/tightness, unthread it, and tell me what you see on the pipe's threads
  • Like Big Ed,

    I never have been too much of a teflon-tape user, but it does have its place.
    Sometimes the steel fittings can`t even be screwed together much more than 2-3 turns,, I feel "fattening" them up with tape would surely crack the fitting as well.
    Can`t win for losing.

    Dave
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,858
    Junk thread science...

    My father, rest his soul, use to speak of Goose Grease. He also spoke of Red Lead and Litharge and Glycerin. He said that if the threads were properly cut, that all that was necessary was a lubricant to keep the threads from chattering and possibly galling when they tightened up. Bear in mind that this man also understood how to cut a threaded nipple that could intentionally swivel, for purposes of rocking the final set of a radiator into place... Wish I'd paid more attention to the old man.

    Today, we use BlueLoc, 5 wraps of Teflon, and a final coating of BlueLoc. Labor intensive, yes, but not nearly as labor intensive as having to drain down a system to effect a repair.

    In REALLY tough situations, we will employ hemp, which one of our employees has his father in Ireland send us. We generally reserve the hemp for BSP straight thread to NPT tapered connections, which are almost guaranteed to leak. Maybe the use of hemp is where the term pipe DOPE came from???

    Pure conjecture on my part.

    I do however, seriously doubt that pipe threads are going to get any better. Too much competition on the world market. Quality sells, and I for one would be willing to pay more for quality, especially if it was made here in the good old USofA. Are you listening American fitting manufacturers? You have to SELL your high quality. It won't sell itself, because everyone (distributors and wholesalers) is looking at PRICE.

    ME

    There was an error rendering this rich post.

  • Chris Kuzila
    Chris Kuzila Member Posts: 11


    Sanding the threads lightly will allow the joints to be made up as far as you want. Chris
  • hot_rod
    hot_rod Member Posts: 23,362
    One up on hemp

    is this dental floss looking stuff from Loctite. Folks were grabing free samples at ISH Frankfurt like candy. Makes me wonder if the Euro fitters are having the same threading problems. Much easier to handle than hemp.

    I like this thick ply "3 Wrap" teflon tape. Easier to use and 3 wraps do the job.

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • thick 3 wrap

    i like the pink because it's thicker, and the way it imparts itself to the threads

    that loctite product looks interesting, and if i can find it i'll try it
  • Derheatmeister
    Derheatmeister Member Posts: 1,580
    US Fittings

  • scrook_2
    scrook_2 Member Posts: 610
    Loctite 55 thread

    I think McMaster-Carr has it in their catalog if your local supply house doesn't have it and you can't find a Loctite distributer who stocks or can get it.
  • excellent scrook

    i'll order some from micky c tomorrow
  • mtfallsmikey
    mtfallsmikey Member Posts: 765
    It was nice...

    In the "old days". Dad's favorite pipe dope was called John Sunshine. good stuff, with lead. Never a problem anywhere, steam, oil, gas, water...what ever happened to candle wicking? Used to be able to get it at any supply house. Hemp/oakum used on lead joints only, still have all of Dad's old joint runners, straight/offset yarning/driving irons, etc. Last lead joint I did was around 5 yrs. ago.
    BTW: Nice to hear from you again, Mr. mvickers!.How are things? Everything ok here in the Big City.
  • Joe_135
    Joe_135 Member Posts: 2
    fittings

    Homeowner here. I put in a Munchkin a couple of years ago. I did pri.-sec. and used all non-ferrous fittings throughout the installation. No local supplier in town had nonferrous fittings big enough so I ordered all off the internet from various places. After I got them and looked them over, I see all were made in China.

    I used a brazed plate heat exchanger to connect my outdoor wood fired "boiler" to the system. The Munchkin has 1¼" connections, as you all know. The HX has 2".

    To connect the Munchkin to the system, coming out of the Munchkin I used a 4" long 1¼" brass nipple, a brass union, another brass nipple, a brass elbow, which then connected to the 1¼" copper lines. Did this on the inlet and outlet. All this to allow me to remove the Munchkin in the event of some disaster.

    For the HX with its' 2" male connections, I came off them with 2" SS union, a 2"x1¼" bushing and then the copper lines.

    Every threaded joint on the brass unions leaked, even the ground joints (I think that's what you call them). I removed the brass unions a month ago to try and remedy the situation. They had been installed with teflon pipe dope. I had them tight and they were hard to break loose. Both ground joints and one threaded joint on one of the SS unions leak, also.

    With the union removed, I looked at the thread form on the brass nipples and they appeared thin and straight up and down, not much of a "V"!!!! Not sure if that was from me having them so tight or if they were just piss poor fittings to begin with. After reading on this site, I cleaned all the old pipe dope off and put a layer or 2 of teflon tape and slathered pipe dope on top of that and put them back together.

    Now, only the ground joints leak on the brass unions. I haven't tackled the SS fittings yet- they don't leak as bad as the brass fittings did.
    I've been thinking of making a "gasket" to go between the faces of the ground joints of the unions to stop that leak.
    What do you think of that idea?
  • Clif Heeney_2
    Clif Heeney_2 Member Posts: 53
    Plumber's Hemp and Paste

    Hey Tim!

    Nice to hear that it is working for you. Another good thing about using hemp and paste is the ability to loosen a made up joint slightly if necessary without it leaking.
  • Joe_135
    Joe_135 Member Posts: 2


    ...what, am I a thread killer? Bump
  • imperfect threads

    what do you see, when you do that experiment?
    i heard that the threads are in as much danger of leaking from OVER tightening as under.
    what about liquid dish soap as a lubricant, especially for brass-easy to clean up.compatible with teflon [what isn't?]--nbc
  • Tekkie
    Tekkie Member Posts: 58
    No

    The thread is still there... baadum
  • Chris Kuzila
    Chris Kuzila Member Posts: 11


    I always hit the faces with sandpaper, lubricate with soap, like dawn or joy, the faces and threads on nut and body.
This discussion has been closed.