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Grease guns are simple: A spring-pressured plunger pushed on the grease cartridge, and pulling the trigger lets out a bit at a time. So we're already halfway done!
Sadly, it's not THAT kind of trigger, and at the moment, I'm still trying to devise a trigger mechanism for it; Considering the rod is 1/4" diameter, the logical option is the caulking gun/ultimator trigger, where friction holds it in place as you pull back, then pulling the metal plate with a hole in it lets the plunger go. That would reduce plunger travel, though....but make finding a spring replacement easier. Oh the options the futures may hold.
Unscrew the top piece, so that only this is left^
Take the plunger out. You can see it has a skirt seal - but facing backwards. We can fix that!
Shave these off the rear of the plunger rod. Then you can take everything off, flip the skirt, and reassemble.
This shows the end result. Reassemble so that it looks like the first picture.
Shave down a 1 1/4" to 1/2" PVC bushing, on the inside of the 1 1/4" pipe side, s that it can barely slide over the plunger tube. Use your choice of adhesive to put in place.
And that's it; testing will commence tomorrow, but preliminary tampering says you need pretty loose barrel material (PETG, brass, etc) for best performance. It's at least hitting the other side of my basement, so that's a good thing.
This could be spring replaced, if an appropriately sized spring is found. Or, it could be a candidate for turning into a BnA of sorts, a miniature Aabow.
Edited by Buffdaddy, 28 July 2011 - 11:43 PM.