UPDATE 10/Nov/2021

Added piston files with the core filled in to make printing easier for those just looking for functionality.

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This is a model of the pneumatic pump assembly off the 1989 Kenner, The Real Ghostbusters, Ghost Trap.

I have modeled this off an existing, intact, assembly. This will allow you to print off replacements to restore the toy. The main body of this assembly often gets cracked, causing air to leak out of the cylinder rather than push the piston to open the trap doors.

There are 2 versions of the main body. One is a replica of the actual part and the other is the same part without the nipple so that you can install your own, if you wish.

Parts have been tested on an FDM printer and work properly.

GBFans Project

Print Suggestions

Pump Body

The Pump Body prints well with the cylinder opening on the build plate with supports turned on. The print should just bridge the bottom of the cylinder instead of creating support. If your slicer puts support in the cylinder, put a blocker in it. Printing the other way around (with the X toward the build plate) will leave you with a lot of support to remove on fairly thin parts.

Pump Piston

The Pump Piston is best printed with the guide arms against the build plate. You will need to turn on supports for the midsections. This is the best orientation because it leaves the smoothest surface for the areas of contact with the Pump Body.

Assembly Note

There is a piece of plastic film between the Pump Piston and the Pump Piston Cap. This film is 25mm in diameter with a hole in the middle to accommodate the bump at the top of the piston. The film feels about the same as a sandwich bag. On my assembly, there was also a small bit of grease around the perimeter of the film.