Making a tap

[4x4mike]

Not a tap exactly but something similar. I wish to thread an existing hole with 1/2" NPT. The hole is already the proper size it just needs threads. Here is the easy part, both pieces are plastic. The hole is actually the pouring spout in the lid of a Specter MWC, it's pretty rigid but I think will cut easily. I want to thread in a short section of grey PVC that is threaded in each end to make a spout for a nozzle off the lid. It wouldn't be used all the time and I want the lid to seal like factory and I figure this is the least damaging.


I bought a 3" black pipe section with the male threads and was wondering if I can modify it to cut the threads. I was thinking about cutting (grinding) a couple of flutes and then threading it in with some pressure in hopes the modded pipe will cut thread and the flutes remove the cuttings.

What do you all think? Will it work or is there another way I should go about this?

[4x4mike]

After trying to find the thread on my pitch finder I'm not sure the thread I'm looking for is NPT but that doesn't matter because I have a metal section in the proper thread.

Here is the lid

[img width=800 height=600]http://i36.photobucket.com/albums/e13/mezamichael82/Specter/DSC07944.jpg[/img]



I want to thread this in here.

[img width=800 height=600]http://i36.photobucket.com/albums/e13/mezamichael82/Specter/DSC07945.jpg[/img]


Then assemble this to it.

[img width=800 height=600]http://i36.photobucket.com/albums/e13/mezamichael82/Specter/DSC07946.jpg[/img]

[garrett]

probably not what you're looking for but you could get another tan piece (or replacement cap maybe), use just the cap that fits the outside threads, drill it out and glue an extension into it and use it as an attachment.

otherwise, i guess you could cut flutes and try to grind a taper on the end and see if it works as a tap. have never tried anything like that...

[Seanz0rz]

go get a black iron pipe of the same threads, clean up the threads with a thread file and wire brush. clamp it in the vise, heat it up with a torch and start threading. just keep it moving, dont let it sit on the pipe while it cools, just thread it on and back off.

[4x4mike]

probably not what you're looking for but you could get another tan piece (or replacement cap maybe), use just the cap that fits the outside threads, drill it out and glue an extension into it and use it as an attachment.

otherwise, i guess you could cut flutes and try to grind a taper on the end and see if it works as a tap. have never tried anything like that...

The caps have a unique thread and I've already looked into going that route. I did think about glue but I've got 2 of these cans and wanted to keep the caps intact. If I can find another cap for cheap I may do something permanent.

[4x4mike]

go get a black iron pipe of the same threads, clean up the threads with a thread file and wire brush. clamp it in the vise, heat it up with a torch and start threading. just keep it moving, dont let it sit on the pipe while it cools, just thread it on and back off.

I already have the black pipe, it is the one I was going to cut flutes into. I didn't think about heating it. Don't you think it'll make the OD too large? I want this to be pretty water tight. I imagine heating it up and it just making a gooey mess with no threads. I have no idea what plastic they use on these.

[mastacox]

Why not just buy a tap? What am I missing? They aren't that expensive...

http://www.amazon.com/2-14-npt-taper.../dp/B000GAQEEK

http://www.harborfreight.com/cpi/cta...emnumber=91395

[BruceTS]

haha too bad you don't live closer to me, I'd let you borrow one of my taps....

[Robinhood4x4]

I don't know if it'll work but I like your spout idea. You can try doing a test run into wood to see if your pipe idea would work.

[4x4mike]

Why not just buy a tap? What am I missing? They aren't that expensive...

http://www.amazon.com/2-14-npt-taper.../dp/B000GAQEEK

http://www.harborfreight.com/cpi/cta...emnumber=91395

You know I never searched online. I went to 2 places local to me and the taps were close to $40 so I figured I'd shove a sharp pipe in there. I'll call my local HF and see if they have that kit. Thanks.