CSV Launcher Trigger Assembly

Update

(9/2007) As we finish up the last of the August batch of launchers a change is being made. Due to some recent problems with triggers, a change is recommended. In the past we recommended glueing the trigger. Long ago we used epoxy, then some time back we changed to CyanoAcrylate (CA or Krazy Glue). This glueing does not work consistently - sometimes it holds well, others not. Combined with occasional problems with the triggers, and the problems of getting the assembly apart when glued, leads us to this: We’re not going to glue the triggers on production launchers starting today, and at the moment we recommend against glueing them, at least initially. The alternative is to use teflon tape. This seals well, and leaves the trigger assembly serviceable. The downside is that the trigger can move around if forced. This is not a problem, though it can be annoying. If you find it annoying you can glue your trigger after your launcher has proven that it works well.

Overview

There are two threaded 1/4 NPT threaded joints that connect the trigger to the valve top. In the following procedure they will be cemented to keep them in the proper position. Prior to cementing, the The trigger assembly can be screwed together without cement using teflon tape, and the launcher tested to insure that trigger airflow is adequate. TESTING IS RECOMMENDED. After testing cementing the trigger is recommended. See LauncherTesting.

Glueing the Trigger

NOTE - you can cement the trigger, however at this time (9/2007) we do not recommend glueing, instead just use teflon tape for better serviceability.

A new technique of assembling the CSV Launcher trigger subsystem has been developed. CyanoAcrylate (CA) cement is used instead of epoxy. This results in an easier installation.

Preparation

• Parts
  • trigger valve
  • brass elbow
  • valve top
• Tools and Supplies
  • small tube or bottle of regular (thin) CyanoAcrylate cement (superglue)
  • paper towels
  • q-tips
  • alcohol (avoid additives that will interfere with cleaning)
  • Safety Glasses
• Hazards
  • CA glue can instantly bond skin, avoid contact
  • CA in the eyes is bad, use safety glasses

Process

• There are three components in this assembly. The trigger itself is a pneumatic air duster or blowgun. The main launcher valve top, and the brass elbow that interconnects the two. Identify and locate these parts.

• The top of the main main valve should have been removed (six screws), masked, and epoxy installed to block the three small holes prior to proceeding with this assembly operation. (If the launcher was assembled and tested then remove the valve top (six screws), and disassemble the unit down to the three parts - trigger valve, brass elbow and valve top.)

• Make sure that the air input adapter at the bottom of the air duster is turned into the body all of the way and tightened. Some are loose from the factory. Avoid overtightening as this may break the trigger.

• Clean the threads on the trigger, elbow, and in the hole in the center of the valve top. Alcohol and Q tips work well for this. Allow to dry.

• Avoid touching the now clean threads. Install the brass elbow on the bottom of the trigger assembly. Turn it on snug. Orient the the elbow pointing to the left when the outlet of the trigger is pointing away from you. This is the orientation the elbow should be glued in. Refer to photos of the launcher to be sure this orientation is correct.

• Unscrew the brass elbow 2 turns. Apply CA cement to the now-exposed threads. Turn the brass elbow back on 2 turns and line it up in the proper orientation. Wipe up excess cement, taking care not to touch it. Set the parts aside and allow the cement to set.

• CA cement may take awhile to set, depending on the water content of the air which triggers the reaction. Breathing on it to condense some moisture can help. Leaving it set for a few hours or overnight works also. Using a CA Accelerator causes the reaction to occur in a couple of seconds but weakens the joint slightly.

• After the glue has set, turn the elbow/trigger into the center hole of the valve top about 3 turns. Line it up, with the trigger handle over the small threaded hole (now filled with epoxy). Holding the trigger outlet pointing away from you the valve top should be on the left, and the large hole in the valve top (that was for the solenoid) should be facing toward you. The handle of the trigger should be centered between two of the valve top mounting holes so the screws (and screwdriver) will pass the handle when assembling the valve top to the valve body. Refer to photos of the finished launcher to insure the orientation is correct.

• Loosen the trigger/brass elbow from the valve top by 2 turns. Apply CA cement to the exposed threads and tighten 2 turns back to the proper orientation. Wipe up excess cement. Put aside and allow the glue to set.

This completes the Glued Trigger Assembly

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AlanB