Standard bike axle query?

[cakedwi'mud]

Please help, i feel a tad foolish even having to ask this as i've been tampering with my bikes for over 20 years quite successfully. but... i recently bought and fitted a new standard axle for a bmx but as it is ridden it starts to work loose, i took it out and re inserted it the other way around but that meant that it would tighten whilst being ridden to such a degree that the wheel stops turning completely. what am i doing wrong?

 

[bikeworks]

Hm. You mean an axle for a hub, correct?

Physics would dictate that it would loosen, not tighten as you were riding and that it doesn't make any difference which way it was installed, but I have an idea. If this insults your intelligence I apologize but I am trying to think of everything.

1) No locknut on one or both of the cones. This is the only way a cone could move one way or the other.

2) Too many bearings. Install the bearings until the cup is full, then remove one.

3) Bearings too small. Forces them to "bunch up" and lock against cone and cup.

4) Cones too deep, contacting the cup or inside of the hub shell.

5) If the bearings are in a retainer, the retainers may be installed backwards.