Can you fix a low pressure gauge?

I've pieced together a four way regulator snagging various pieces on eBay. I bought some new 30 psi low pressure gauges too. After putting it all together and pressure testing with some soapy water I found some leaks. In the fray of tightening the connections and fixing the leaks I bent three of my four gauges. The faces are warped to where the needle won't freely move and they are not reading accurately (one of the eBay buys came with a little tail piece to attach a gauge to the output to test).

Is there a way to fix/calibrate these or am I out these new gauges and stuck waiting for more to ship?

you can unscrew them from the regulator body and they should come apart with a few screws. you can carefully bend the face plates back.

however, if they were hit hard enough to bend in the first place, the accuracy could be gone now. setting 12psi on the gauge could actually be 5 or 20 psi. if you fix them, i would definately check them against something known to be accurate. otherwise you should just replace them.

Of the four low pressure gauges, three were bumped. I hooked up an extra gauge to output of the fourth that was not bumped/bent. Both gauges were measuring the same, so that fourth gauge and the testing gauge should be fine. When I went to hook up the testing gauge to the three bent gauges though they were definitely off. They did not read anywhere close to what the test gauge was reading. So long story short, yes the three gauges I'm worried about are not reading correctly.

So, is there a way to calibrate them using this test gauge on the output, or are they pretty much shot?

I just hate to replace them since they are brand new, but then again for $20 is it really worth my time to try to re-calibrate these things.