Brazing kills sharders

[john bunsenburner]

Last night while making my chamber i brazed a tire valve into a hole at the end cap of my iron chamber. When i was done and everything had cooled i inspected the valve and noticed it was broken, i fixed the problem with a checkvalve from a pump which screwed on but i would like to know why the sharder broke and if i could fix it:

The sharder is brazed onto a tapped iron end cap. there is white and black residue on the inside which i noticed after brazing. The rubber at the bottom of the sharder has bin removed and i used a silver based brazing rod with a melting point of 690°C. There was some smoke while soldering but i suspected it was simply the rest of the rubber burning off, which in turn happened. The part which has to be pressed does inoreder to release the pressure inside the bike(or inorder to fill it) moves around freely when i shake it. When i blow into the valve it is slightly easyer to blow than to pull. Pictures will be attached, note it is night time here and i am in underwear incase some one might be disturbed by this i mentioned it now before things being too late:

[Gippeto]

Last night while making my chamber i brazed a tire valve into a hole at the end cap of my iron chamber. When i was done and everything had cooled i inspected the valve and noticed it was broken, i fixed the problem with a checkvalve from a pump which screwed on but i would like to know why the sharder broke and if i could fix it... If you need details on what is wrong i could check, just ask me.

DO NOT respond to this post. *** READ it.***

I for one, have had enough of your BS posts.

If you can't put the details in the first post, why should "we" continue to try to help you.

Edit your first post, and put the details in it.

Be PRECISE with your description.

Better yet, include a picture.

I will not be responding to your posts in the future unless you figure this out.

I encourage other members to do the same.

Enough IS enough.

[Hotwired]

The schrader valve is a metal tube threaded inside and out with a small sprung poppet valve that screws down inside it.

The metal outer tube will not take notable damage from being brazed, the poppet valve insert will however, the spring inside may lose its strength and the seals will certainly melt or burn.

You can remove the poppet valve from inside the stem with a special tool or faff about with a pair of tweezers.

[john bunsenburner]

Ok sorry, i just dont have a camara at had, im really sorry, ill suply as much detail as i can in an edit, and maybe i can use a webcam to make a picture. sorry...

[Ragnarok]

I'm not sure that's fair Gippeto, he doesn't necessarily know what information is needed - he's new to the hobby, he hasn't learnt about all of the pitfalls yet. I'd probably have to ask what I should be looking for to diagnose the problem if I had an electronics problem, because I don't know electronics.
Indeed, you asked about why your chronograph wasn't working the other day, because you didn't know what was causing the problem.

Like you, he knows there's a problem, but he doesn't know what the cause is. That's what the forums are for, sorting out these things. And anyway, there's enough information to answer his question there.

but i would like to know why the sharder broke and if i could fix it.

Because you exposed it to the heat of brazing - there are rubber parts in those that can and will be destroyed by high temperatures.

No, it probably can't be fixed, although you could try again with another schrader, but this time, extract the internal parts before you braze it, then put it together after it's all cooled.
If you get a set of long nosed pliers, then you should be able to reach into the end of the valve and unscrew/remove the heat-vulnerable parts. Screw them back in again when you're done.

[twizi]

Ragnarok right the rubber seals the schrader if it heated above 110 i would think it would deform and not seal

[john bunsenburner]

Look at my edited post, i might be a noob but i have too much pride to let people call me one, i hope the new version supplys all information needed, for you gipetto, if it does not then go screw your self, it may sound harsh but i told you all i know in a third language of mine during an influenza infection that has been lasting two weeks now, i barely have the power to stand up to get a dring from my fridge but i had to demonstrate that i could do better, thank you and i hope you like it and that you decide that reading a noobs post is worth it and that you respond to my post.


@rag: Is there something besides a checkvalve, like a second sharder or something that i could screw ontop of the broken sharder and have a funtioning valve or not? could i replace the rubber seals?

[Ragnarok]

@rag: Is there something besides a checkvalve, like a second sharder or something that i could screw ontop of the broken sharder and have a funtioning valve or not?

If you have a second schrader, you might be able to swap the internals of them over and fix the first one.

[john bunsenburner]

I have a second one, what exactly do i have to take out i am a little unsure about it and i do not feel like breaking another sharder, is there an instructable some where or yould you explain and elaborate a little and add some detail so that both gipetto and i are happy(sorry i could not resist that little joke there)

[THUNDERLORD]

I'm not sure that's fair...

Me too, as it made me think harder about ways I'd fuel a mini-hybrid.
(Especially since I've considered pre-mixes).
I plan to situate the fuels and fill valve in a spot below and forward on the barrel but it's much better to avoid the possibilities...

I'm surprised since pumps generate heat usually by compression alone.

@rag: Is there something besides a checkvalve, like a second sharder or something that i could screw ontop of the broken sharder and have a funtioning valve or not?

Not directed at me but you could possibly grind/cut the top of a metal valve cap (to make a coupling) then cut the base off another and epoxy the threads and screw them together (before it dries) (?).

EDIT: Dang I type slow! The internals unscrew by turning the flat sides of the pin. once you unscrew it it's pretty self explanatory.
I thought it had broken in half but was already welded maybe. Good luck on it. 8)

[SEAKING9006]

That's why I asked for a pack of threaded 1/4 MPT shraeders for christmas. I am getting tired of using expensive quick-connect and ball valve setups. I don't have the- wait, yes I do. Here's the link for 1/4 NPT threaded schraeder valves.

[john bunsenburner]

I am not sure what you mean by your first part of the post but i will ignore it as a wierd joke and i do not like improvises glued together wierd joints, i prefer the meathod recomended by the guy who posted before you.

[THUNDERLORD]

I am not sure what you mean by your first part of the post but i will ignore it as a wierd joke and i do not like improvises glued together wierd joints, i prefer the meathod recomended by the guy who posted before you.

If that was directed at me?
I made no wierd joke, just explained this post caused me to think that for safety in fueling a hybrid some other valve should be used since heat will affect the shraeder valve (without the heat factor they could withstand high pressure).

I had added an edit, but Like I stated, I type slow.

Now for the weird joke:

... note it is night time here and i am in underwear incase some one might be disturbed by this i mentioned it now before things being too late:

I'll just drop it, it's TMI, heck I understand, when I look at some designs just guess where my hand is (Not really but it's a funny wierd joke though right?)... 8)

[john bunsenburner]

Ok lets drop our little wierd joke act, and i will fix the shader as soon as i put a pair of pants over my boxers tomorrow morning (or like most of the time i wont and i will dremel and weld in underwear which looks very silly)...haha

[starman]

You obviously melted the rubber sealing parts inside the schrader. Most of the non-tire type schraders are threaded so you should plan to drill and tap or cement (JB Weld) and not braze your schrader.