Threaded schrader valves

sjog · Mon Apr 30, 2007 10:27 pm

Look near air tool/compressor parts, I got one that is npt 1/4 " there

pyromanic13 · Mon Apr 30, 2007 10:34 pm

I think it's 3$ at my local napa

chpiai · Tue May 01, 2007 2:57 pm

If you are having trouble getting hold of schrader valves with standard threads, I've noted that the ordinary valves found on bike inner-tubes fit very neatly in 8 mm compression fittings- those that screw tight with a brass olive. If in place of 8 mm copper tube, you use the schrader valve, it gives you a (rather bulky) valve that is compatible with ordinary plumbing fixtures. I have yet to test this arrangement under pressure - reinforcing with solder may be appropriate, but it seems to seal securely.

meatballs · Tue May 01, 2007 5:45 pm

great idea, i'll have to try that. I'm all set on schraders for now, but i'll remember that when i need one. i'm not sure the solder would work so well, everyone thats tried it seems to have broken the schrader in some way. you might try epoxy, or my personal favorite, CA glue. I use CA glue to put the schraders in 1/4 x 1/8 threaded brass bushings, and it works great. should work in a compression fitting too, it wouldn't be removable any more, but thats not really the point. i don't have much personal experience with compression fittings, about how much would one like that cost?

SoCalSiege · Tue May 01, 2007 7:11 pm

they do indeed have threaded schraders at the local auto store...they are like 10 bucks for 2.

pyromaniac · Tue May 01, 2007 7:19 pm

if you want you can take a knife to all of the robber on one and stick in in some tube hose clamp it put the hose over a hose barb then screw that in.

that would be very ugly and inconvenient.

lukemc · Tue May 01, 2007 7:42 pm

Gsu wrote:Right now I bored out a 1/4" end cap and soldered a bike shrader into it atm. Unfortunately that broke the shrader so it leaks a bit, I guess it melted something inside. You could try heating the parts to be soldered up separately making sure you only heat up the shrader for a couple sec, only the outer bit of the thread.

ahh you have to take out the middle part (i dont think there is a name for it) then solder it so it dosent melt at all

cyanite · Wed May 02, 2007 2:34 am

A car tire valve is probably the way to go... However, I have used a bike tire valve with a piece of tube still stuck to it, If you push this into an end cap, from the inside, it seals perfectly, provided your hole is tight enough.

On my mates launcher, the rubber square came off ( too much heat/pressure no doubt). I wrapped the rubber bottom part of the valve in teflon and crammed it down the hole, expecting it not to hold... suprisingly, it did, hasn't moved or leaked since, to 130PSI. Proves ghetto solutions work

chpiai · Wed May 02, 2007 5:02 am

meatballs wrote:great idea, i'll have to try that. I'm all set on schraders for now, but i'll remember that when i need one. i'm not sure the solder would work so well, everyone thats tried it seems to have broken the schrader in some way. you might try epoxy, or my personal favorite, CA glue. I use CA glue to put the schraders in 1/4 x 1/8 threaded brass bushings, and it works great. should work in a compression fitting too, it wouldn't be removable any more, but thats not really the point. i don't have much personal experience with compression fittings, about how much would one like that cost?

Don't know where you are, but in Britain an 8 mm compression straight-coupler is about £2

meatballs · Thu May 03, 2007 10:16 pm

I'm in the US, so £2 is 3-4 USD and since inner tubes are free and a nipple or bushing is ~$1 i think i'll stick with that. and in the US we ddon'thave readily available metric compression fittings. we still use that silly english system. i suppose it sshouldbe renamed the american system since we are just about the only nation foolish enough to use it. The hose clamp + hose barb idea is creative, but like you said ugly and impractical. Does anyone know if they make a piece that is a schrader valve on a quick disconnect rather than just threaded? that would be convenient so you could sswitchbetween using a bike pump and a ccompressordepending on what's available.[/img]

frankrede · Thu May 03, 2007 10:26 pm

bboymatty wrote:go to a local auto store that sells bits and bobs for auto's, and look for the metal threaded schraeders they sell.

I picked mine up from REPCO, for $18 AUD, and it works a treat, has a screw on one end and a plastic bumper on another to seal off the thread.

Those ones are the best.

meatballs · Thu May 03, 2007 10:40 pm

those sound great, about how many USD is 18 AUD?

Slugfoot · Thu May 03, 2007 11:58 pm

Just in case you have no luck buying some...
The schrader on my copper spudgun is salvaged from a bike inner tube.
First, I removed the insides using a schrader tool then I cut off as much rubber as I could. The remaining rubber was burnt off with a blowtorch (this took ages) and thouroughly cleaned with a wire brush. It is vitally important to remove all the crap from it or you won't be able to solder it.
The schrader had a lip on it which allowed it to sit in a washer of the right size and these were then soldered into a drilled end-cap and the innards replaced.
It has never leaked or given any trouble and has held pressures in excess of 200psi regularly.

chpiai · Sat May 05, 2007 4:40 am

meatballs wrote:I'm in the US, so £2 is 3-4 USD and since inner tubes are free and a nipple or bushing is ~$1 i think i'll stick with that. and in the US we ddon'thave readily available metric compression fittings. we still use that silly english system. i suppose it sshouldbe renamed the american system since we are just about the only nation foolish enough to use it. The hose clamp + hose barb idea is creative, but like you said ugly and impractical. Does anyone know if they make a piece that is a schrader valve on a quick disconnect rather than just threaded? that would be convenient so you could sswitchbetween using a bike pump and a ccompressordepending on what's available.[/img]

Actually the use of non-metric pipe fittings isn't uncommon in the wider world. If 8 mm fittings are unavailable, you can probably get 1/4" fittings, which are in fact 0.375" outer diameter, vs. 0.314" for 8 mm tube. 1/4" may be close enough to still fit.

chaos · Sat May 05, 2007 5:13 am

These are the valve i got the have 2 rubber seals on either side of the "wall" of wateva its going in.

I had a rubber tubeless valve on my first pneumatic and failed at 260psi after the 6th time it was filled that high,

*scary coz it was just after i got my stitches out after the "accident" so yer it was nearly 2 incidents within 2 weeks

.*

mmmmm... so here are the ones i got from my local tyrepower store, there chromed and all *shiny*

for $5 a piece, i think it was a good deal so i got 4 of em.

EDIT: Soz ill get the pics up Monday i cant seem to find them right now.

Threaded schrader valves

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