Inserting a piston into a threaded tee

[goose_man]

I was looking at a 1/2" female threaded brass tee and I noticed that the path from the end of one side of the threads to the one across from it is rather smooth, unlike the indentation in a copper or PVC tee. I was thinking how easy it would be to make it into a piston valve especially because I have a brass tube that fits perfectly inside a 1/4" male nipple.

I would attach a 1/2" to 1/4" threaded flush bushing into the barrel end of the tee and screw a 1/4" male nipple into it. I could then epoxy my brass tube into the nipple so it extends to the piston (the piston would seal against it).

There's only one problem: How can I get a piston into the tee? I've been thinking about it for a while and I can't seem to come up with a sufficient answer. Maybe I could make two halves of the piston and glue them together inside the tee (tricky)?

As far as my backround in making piston valves, I've made a PVC piston valve in a 1-1/4" tee before and used O-rings so it performed very well. Though I have no way of testing this for certain, I'm sure that even though it had only 3/4" porting that it out performed my 1" modded sprinkler valve.

Any suggestions on how to get a piston into the valve would be greatly appreciated. Thanks in advance,
-goose_man

[subterranean]

pictures would help alot.





modd delete this later

[super spuder]

Sorry. But this makes no sence to me.

[goose_man]

Okay, sorry. I just drew a picture/diagram on paint but ImageShack is giving me some problems so I'll try to explain it better: Basically, I want to make a barrel-sealing piston valve inside a 1/2" threaded female tee. I can't fit a piston past the female threads. Any piston with a small enough diameter to get past the female threads has too small of a diameter to fit well in the tee as a piston.

Maybe I have to cast a piston inside the tee?

[super spuder]

ooh. I think i know what you mean now. if you are having the same problem i hade (the piston it getting stuck at the back of the threads) just take a piece of sand paper and sand down the little ridge at the back. i will maybe have a pic of what i mean soon

[super spuder]

i cant post the pic

___________////////Threads
--------------
on my it hade a bump just above the happy face. is that what u mean?
sory about the dotted line. the happy face kept moving to the left

[subterranean]

From what i think your tring to say. You might just make the piston a little bit longer and have half the piston one diameter, and the other half the diameter of the threaded area. heres what i mean(pic of piston below)


l---------l
l 00000 l-------l
l 00000 l-------l
l---------l

[goose_man]

Thank you, I got it now.
-goose_man