MVP ATC-4000 Series, Repair Manual, Page: 15 / 55

ATC Chopper Gun Operations Manual
Page | 15
Grounding straps should be installed on all loose conductive objects in the spraying area. This
includes material containers and equipment. Magnum Venus Products recommends grounding straps
be made of AWG No.18 stranded wire as a minimum and the larger wire be used where possible.
NFPA Bulletin No77 states that the electrical resistance of such a leakage path may be as low as 1
meg ohm (10 ohms) but that resistance as high as 10,000 meg ohms will produce an adequate leakage
path in some cases.
CAUTION
Whenever flammable or combustible liquids are transferred from one container to
another, or from one container to the equipment, both containers or container and
equipment shall be effectively bonded and grounded to dissipate static electricity.
For further information, see National Fire Protection Association (NFPA) 77, titled
“Recommended Practice on Static Electrical”. Refer especially to section 7-7
titled “Spray Application of Flammable and Combustible Materials”.
Introduction
The AT series guns are some of the most advanced state of the art guns introduced into the
composites industry. They feature low maintenance, few adjustments, superb quality, and a long
service life. The AT series guns are air trigger guns; as the trigger is pulled, air is shifted from one
side of a piston to the other. The pistons are attached to the gun needles and the air shifting opens
and closes the needles. The ATC chopper has a poppet valve which is pushed when the resin
needle moves to the open position, allowing the chopper air to be turned on and off by pulling the
gun trigger.
This manual provides information for the operation, maintenance, and simple repair of the MVP
ATC Chopper Gun. The following procedures are included:

Step-by-step assembly and disassembly

Troubleshooting guidance
Please read this manual carefully and retain for future reference. Follow the steps
in the order given, otherwise you may damage the equipment or injure yourself.
As you disassemble the equipment, lay out the components on a clean surface in the correct order
and direction to assist with reassembly.
This manual cover all the variations of the ATC Chopper Gun:

ATC-4000-XXX External Mix Chop Gun

ATC-6000-XXX External Mix Chop Gun – With Signal