Please help with a bent pressure gauge screw (#149-1)

    I finally received my Petromax 500CP that I purchased from eBay Germany yesterday. She is a 1960 German Army Petromax 829 500cp. Upon removing the lantern out of the box, I immediately noticed that the pressure gauge screw #149-1 was completely bent inwards. I attempted to remove the screw in order to preserve the original gauge and was unable to do so. The bend in the screw only allows me to turn it about 10-15 degrees in each direction before stopping.


    My question is: What steps I can take in order to successfully remove the damaged screw without actually destroying or damaging the inner threads, which seem to still be in tact (for the 10-15 degrees the screw does spin, there is no resistance which leads me to believe the threads are still in tact).


    You might be reading this and saying just throw away the entire unit and buy another #149, but I am trying to avoid that option as much as possible. Why? Because there is a clear quality difference between the ones made in the 1960's (German made) and the current ones that are of oriental origins which never properly hold pressure etc. When comparing this German gauge to my current China made gauge, I can easily spot the differences in the weight, quality of the glass covering the number etc.


    The two options I have considered in removing the damaged screw are 1) Bending the screw back out and attempting to screw it off 2) Dremel (cut) the visible portion of the screw off, then drill out the inner remains with a smaller bit (probably not as easy as I think it would be)


    What other options would you guys consider in terms of removing this screw? I am really disappointed with this and would love to preserve the gauge, and the lanterns all German workmanship.


    Below are some photos and a video showing me twisting the knob from ANY recommendations would be appreciated.


    img0016.jpg
    img0017vw.jpg
    img0018cx.jpg


    And the video showing me twisting the screw to the point it stops at both ends: http://www.youtube.com/watch?v=iUO3dL98lcg

    Hi Adam.


    I think you could fix this problem very easily without any damage of the gauge. Just bend the screw backwards with a good lineman's pliers or comparable pliers. The gauge you can hold with one hand and with your other hand you grab the screw on the top with a pliers and band it back. The screw should not brake, it´s good quality. When you bend it backwards you should look that the screw stands after that upright.

    thank you for the response. thats what i think i will end up trying. I wonder what is stopping the screw from turning any further, maybe it is the bend at the lowest point hitting the gauge.


    Do you know of anywhere I could get a high quality gauge preferably German made?


    thank you

    Hi I received a Petromax from Ebay with the very same problem and I corrected it using pliers as suggested here.


    Anything work nicely now and I didn't change any spare! Just take care of pretecting the screw with some scotch in order to not damage it.
    Hope this helps,
    Carlo

    Hi Adam,


    to your first problem - the screw could not be turned out, because the threads of the old army-manometers are injected at the upper end in order to prevent losing the screw. You can turn it out by using a litte bit violence to turn over the injekted end, and it will work afterwards, still.


    The seal has not to be fixed, it will tighten conical.


    I would turn it down, if possible, until it is sealed, and then force it into a straight position by a plier or so, like already told.


    With a little torchlighter, you coud heat up the screw, so it would be easier and more carefully to the material than coldly deformation.


    Best regards and good luck, Björn :done:

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