Reassembly of the Model 445 (back)

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Reassembly of the Model 445 Pneumatic Nailer.
(Print a Workbench Copy)

Before reassembling the nailer, inspect several key areas for damage.
Inspect the ledge for damage and plunger surface for scratches.
Turn the nailer over to inspect the other side.
To begin the assembly, mount the nailer in the vise with the bottom of the nailer facing up.
Place the rubber seat into the bore with the beveled edge facing up.

Make sure it is seated completely flat around the ledge.

Drop the metal support ring in, on top of the rubber seat.
Coat the cylinder sleeve, inside and out, with air tool oil.
Locate the beveled edge of the sleeve and install with the beveled edge up.
Coat the piston seal with air tool oil.
Insert the drive blade and piston seal into the bore. This will soften and shape the seal.
After 1-2 minutes, pull the assembly out and replace in the correct position with the drive blade up.
Tap the drive blade with a rubber mallet until it seats all the way down into the cylinder bore.
Install the rubber bumper.
Turn the nailer right side up.

Use a piece of wood at the bottom of the vise to support the drive blade assembly.

Install a new return cylinder O-ring.
Oil the plunger seal.
Install the plunger.

Use a rubber mallet to tap in, while rocking side to side.

Install the 3 plunger screws and firmly tighten.

Dip 1/3 of the screw threads into blue locktite.

Firmly tighten all 3 screws.
Turn the nailer upside down in the vise.
Pull up on the drive blade until it is fully extended.
Slide the channel assembly over the drive blade.
Slide the adapter foot over the steel foot.
Install the four 1-1/4" screws with lock washers.
Turn the nailer right side up in the vise.
First install the body plate.
Put the safety yoke in place.
Install the screw for the safety trigger cable.
Apply white grease to the bottom, top and sides of the safety yoke.
Install the safety yoke springs.
Install the metal cap with 4 screws.
Activate the red safety trigger several times while tightening each screw. This will help center the safety yoke under the cap.
After tightening all screws, install the rubber cap.

Use a rubber mallet to tap the rubber cap onto the plunger head.

Nailer is now ready for connecting air and functional testing.