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KHS
March 15th, 2014, 06:46 PM
My problem is a 1944 plastic vac-filler unit that has a bad spring and a damaged pellet cup. Does anyone know the best way to get the old pellet cup off without damaging the plastic plunger, or any of the other plastic bits?

And on a related note, does anyone know what thread die one should use to dress the threads on the blind cap end of the filler, the vac-wrench kinda mushed them a bit...
:redface:

D Armstrong
March 15th, 2014, 07:39 PM
I use a pair of small side-cutters (you know, for snipping wire), aligned parallel with the plunger, but cutting only the fat part of the socket. The socket is made of quite brittle plastic and should split off pretty easily.

You probably should just replace the threaded collar, though. Aluminum is not very forgiving; it just breaks off, rather than re-forming like steel or copper alloys. PM me and I'll look through my parts bin.

David

Jeph
March 16th, 2014, 04:01 AM
There is a very detailed description on Richard Binder's site.
Select Reference Pages from the left sidebar
And then at the bottom of the page under Repairer's Corner
Select "How to Repalce a Vacumatic Diaphragm"

Flounder
March 16th, 2014, 12:44 PM
Over at the restorer's art, David has a nicely photographed complete vac unit tear down (http://www.restorersart.com/breaking-down-a-parker-vacumatic-filler-unit/).

I've found that an abused pellet cup can be swaged back into service by dipping the lip in water off the boil and introducing it round the fat end of a female leurslip syringe needle, if that's any help.

http://i773.photobucket.com/albums/yy19/flounder2009/1950%20Parker%2051%20English%20Black/Vacumatic%20Pellet%20Cup%20Swaging/Black51Vac101.jpg

I've retensioned a slack spring before, but that was a blooming fiddly affair.

KHS
March 16th, 2014, 02:12 PM
That is excellent information about reforming the pellet pocket, thank you!
I think this one has to come off though, to change the spring, the spring in place is in a dreadful state. :(
Luckily I have another spring, and ordered a pellet pocket from the pen sac store. (I gather David makes these?)

Thank You All for your help! I am a tad anxious to reassemble my "new" cedar blue parker 51

Flounder
March 18th, 2014, 06:36 PM
That's my favourite obtainable colour, show it off when you've finished!

KHS
March 18th, 2014, 08:01 PM
That's my favourite obtainable colour, show it off when you've finished!
I will try, I am new to the posting thing...:confused: