What gives on HF pipe clamps HELP

[pierhogunn]

okay, my shinny new HF pipe clamps show up, and boy am I excited, until I try to get them to thread onto the 1/2 black pipe over half way through the order, and over half won't even thread onto the pipe.

WTFunk...

a little pissed, yup

is there a trick to getting these bloody things to seat correctly and thread onto the pipe? I have a few good ones, and a nice pile of not-so-good ones

[sweensdv]

I had the same problem with some 3/4" ones I bought recently. My feeling is that there is a whole batch out there that was threaded incorrectly as yours is not the first complaint I've seen about this. I have purchased these clamps in the past and haven't had this problem before so thats why I think it's a production run or two and not a general fault with these clamps.

[tfm37]

The thread size is 1/2 NPT. This is a tapered thread. Most likly it was not tapped deep enough. Get a 1/2 NPT tap and run it in about 65 or 70 % deep.

[pierhogunn]

get a tap and run it 65 - 70% deep? what on earth does that mean? what would I need to do it? would a corded drill and a vise be tools enough to turn that sort of thing?

[tfm37]

The tap will cut internal threads. You can turn it with an adjustable wrench. Turn it till about 2/3 rds of it is screwed in. If it still won't screw on the pipe, screw the tap in further till it will go on the pipe.
If you don't won't to buy a 1/2 inch NPT tap, and they are pricey, take it to a plumber, local hardware, Home Depot,etc and ask them to thread it deeper.

[AlanWS]

It could be paint or other crud in the threads that keeps them from threading on. If that's it, a tap would work, but you could clean them out other ways as well. A wire brush might work, or a tool made easily from a piece of threaded pipe. As others have mentioned, pipe threads are tapered, so make sure the pipe is threaded enough that the outer threads are small enough. If you can start the threads, you're OK.

If you use a file to cut several grooves into the pipe threads parallel to the length of the pipe, these notches will serve as teeth to help clean out the inside threads of your clamps. (These notches are for the thread cleaning tool, not for the pipes you use for clamps.) Screwing them on and off repeatedly, and brushing off any crud that is released, should allow turning it a bit further each time. Once you can seat all the threads, you are done. If you want really smooth threads, you can put a little grit on the threads, so turning it on and off grinds the threads smoother.

My guess is that there are probably only one or two small bits of something that interfere with threading it on, and a minute or two is all it will take to fix.

[pierhogunn]

cool, I'll try taking the clamps to Lowes plumbing section, along with the pipe I bought there and get them to re-thread both clamps and pipe. I sure want this to work...

Thanks