Is there some trick to rectification?

[Ripthorn]

So I am building a multiple pedal power supply and am running in 12.6Vac and then I run it through four 1n4001 rectification diodes set up as a full wave rectifier.  The problem is that when I take the voltage on the + and - junctions, I only get a fraction of a volt, where I was expecting more like 18V.  Is there something that I was missing?  The output of the rectifier is going into a regulator for 9V regulation, if that is of any importance.  This is my first experience with this, any thoughts?

[Cliff Schecht]

Check the orientation of everything. The diodes or linear regulator could be backwards.

[R.G.]

A trick to rectification? Yes - get the diodes the right way round.

I ...um... neglected to do this on one power supply I designed early in my engineerling days. The lab tech populated up the board for me, turned it on to test, and the 3"diameter by 6" long filter cap sprayed its innards all over the wall and ceiling. He never would fire up a power supply for me after that. 

[Ripthorn]

Hmmm, I went and checked the diode orientation, but I think I have it right.  The stripe points away from the negative junction and toward the positive junction, with the other two junctions being the AC inputs.  When I measure the voltage across the bridge, it gives me 1.36V.  I am assuming that 1N4001 are okay for this job, no?

[Paul Perry (Frostwave)]

You have the right diodes, but something must be connected wrongly.
And that 1.36V is suspiciously like two diode drops of 0.7V or so..
The second circuit here is what you should have: http://en.wikipedia.org/wiki/Rectifier
Note you need the capacitor in place, to measure the voltage..

[Ripthorn]

Well, I got the rectifier working (funny how two leads can look soldered but not be), but now my problem is the LM317T acting strange.