Yes, I decided to use flaps on my new set of Stutzman's wheels. Since everything is brand new (tubes/tires/wheels) I figure flaps can't hurt, only help. So how tight are the bridge nuts supposed to be? Do I tighten them while the tube is deflated, slightly inflated or mostly inflated?
Bill, the bridge washer has nothing to do with the un-necessary flaps. It goes on the valve stem of the tube. Then when the nut is run down you need to tighten it enough to make a good seal and leave it at that.
Hope this helps.
Allan from down under.
I put in just enough air for the tube to take shape (completely round) and then tighten the bridge washer tight against the flap - I also use flaps contrary to some opinions.
Steve, I am a little mystified. The usual way these things go together is:
Valve stem in tube, bridge washer fitted over the valve stem,and retaining nut wound down on the stem to clamp the bridge washer against the tube to seal the stem in the tube.
The flap is a separate item. The slightly aired up tube is first fitted in the tyre, then the flap is fitted in the tyre, and the two separate components within the tyre are fitted on the rim.The flap is in no way fixed to the tube usually.
I remain confused!!!!
Allan from down under.
Again - flaps vs. no flaps....
Depends on what kind of wheel, doesn't it??
Excellent discussion and photos at:
see particularly the post by Dan T on 1/21/12 in that thread.
Once again, thanks to you folks that provide great pictures with understandable text.
AS Allan has mentioned the valve stem is clamped into the tube by the nut which forces the bridge washer to squeeze the rubber hole the metal valve is through to stop the tube leaking around it.
You can then pump up the tube and it will hold air inside the tire if the seal is tight as there is a lot of pressure involved.
If you also add a flap it is just an extra piece of rubber to surround the tube completely so it does not come in contact with the metal rim which could be rough or become rusty or in the case of wire wheels hollows and maybe sharp ends from the spokes.
Here is a sketch of the set up with a flap.
I used this illustration from elsewhere on the forum as a guide for mine, it shows the flap under the bridge washer and nut. Either way will work, I suppose.
Decisions - Decisions...
Two (maybe 3) knowledgeable people with differing opinions.
Oh Solomon - where are you when we need your deciding opinion??
The problem with the illustration above is, it shows the dust cover screwing on to the valve stem. It does not. It screws onto the felloe nut. That is the problem with the reproductions! The felloe nut screws to the valve stem, which secures the valve stem to the felloe, whether you have a wood felloe or a metal felloe. It can be a round knurled nut as on the early cars, or a hex nut as on the later cars. The dust cover screws onto the felloe nut, not the valve stem! As far as flaps go. I got converted real fast. I bought a set of New Zealand Firestones years ago, and I didn't go 50 miles before I had a flat. I put in another tube and had a flat again. I put in a third tube and had another flat. The beads of the tires don't come together like they used to, and they allow the tube to chafe until it wears a hole in the tube. The only way you can eliminate that is to use a flap.
My dust covers screw onto the valve stem, just as in the pictures!
O.K., now I'm really confused! I was looking at the illustration in Lang's, which is similar to the one Mark posted where the flap is secured to the tube with the bridge washer and nut. But apparently it can be installed another way using the bridge washer/nut only on the tube? Which is better and why? I want to do this the right way now so I don't have issues later.
Current production metal stem tubes do not use the bridge washer to "seal" the stem into the tube - I believe it's used to merely to prevent the stem from twisting. If one didn't use a flap, then yes, the bridge washer & nut would tighten down against the tube.
Of the five T's I keep on the road, they all have flaps and I've never pinched a tube installing clinchers - only flat was on the Centerdoor on tour and we picked up a screw.
My dust covers screw onto the felloe nut as Larry mentioned, mine also has a thin rubber washer under the felloe nut (please pardon the dirty felloe):
Jerry, can you post a picture of your setup? Maybe different years have different setups.
Mark, we are both right! The A&H hardware has the dust cover screw onto the valve stem while the B&G combination installs as your pictures show. According to the Snyders catalog the A&H was used on wood fellow wheels, the non-demountable type while the B&G was used on the demountable ones.
Here are some photos of original valve stem parts used on Model T's.
The top two photos are of the early and late style felloe nuts. The bottom left are the two valves stems that work best in a Model T, a 777 and an 888. The nut on the right is the bridge washer nut. I'm adding a photo of the correct bridge washer.