1) Cartridge
2) Tray 1
3) Redrive Cap
4) Back Door
- Disengage the support strap from its 'inverted T' slot and pull the door off its hinge pins.
5) Connection Access Cover
- Open it fully and its hinges can be popped free rearward.
6) Lower Rear Cover w/Fuser Access Door
- Three M3x10mm black washerhead threading screws.
- Open the fuser access door -- two claws.
- Pull the cover away at your left and slide the cover toward your right. A downward-pointing hook will slide off a lip at the rear of the chassis.
- NOTE: The above-mentioned hook makes this an awkward part to get back in place. You have to exactly re-create the cover's attitude as the hook was coming off to get it back on again.
7)Redrive Assembly
- Two M3x10mm washerhead threading screws.
- Two outward-hooking claws, left and right side, at about the middle.
8) Left Side Cover -- T650
- Two M3x8mm black washerhead threading screws in the handgrip wells.
- Two M3x10mm washerhead threading screws in deep wells in the side of the toner cartridge cavity.
- Tug on the front lip of the cover to free it; the cover then comes away easily from its hinges.
9) Right Side Cover -- T650
- One M3x10mm washerhead threading screw at the rear.
- Two M3x8mm black washerhead threading screws in the handgrip wells.
- Two M3x10mm washerhead threading screws in shallow wells in the side of the toner cartridge cavity.
- Tug on the front lip of the cover to free it.
10) Fuser Cleaning Wand Cover w/Wand
11) Top Cover
- One M4x10mm pan head threading screw at the right rear.
- Four M3x10mm washerhead threading screws.
- The front edge has to be forced up past the rear edge of the upper front door. NOTE: It's a bit difficult to get this cover levered back into place at the front, but it is doable without damaging anything.
12) System PCA Enclosure Cover
- One M3x6mm black pan head screw at the upper rear.
- Loosen five M3x6mm black pan head screws.
13) Printhead
- Cable connection 'JGALV01' at the System PCA. (Cut ty-wraps A/R to free the cable.)
- One cable connection at the top left of the printhead.
- Three M3.5x13mm pan head threading screws w/captive washers.
- - -
Optical Skew Adjustment
Note that the printhead pivots on a reference pin at about the mid left-rear. That pivoting is what makes optical skew adjustable. The adjustment range is determined by the printhead fastening hole at the right side end of the printhead. There are two ways to deal with the optical skew adjustment.
Quick Method
For a quick way to adjust optical skew, simply fasten the printhead in place with the adjustment at its obvious design-centre, as in the following photo.
For most applications, the adjustment will be close enough to correct, and perfectly acceptable to the user.
'Correct' Method
To get optical skew set to perfection, proceed as follows:
1) Install printhead with the three screws not fully tightened.
2) Reinstall cartridge and tray 1.
3) Start the printer in DIAGNOSTICS mode. (Hold 'down arrow' and 'right arrow' keys while powering on.)
4) Select REGISTRATION.
5) Scroll to 'Quick Test' and select it.
6) The print you get has marks at the upper corners that make it easy to see if the optical skew adjustment is off. Do the adjustment by trial-and-error, then tighten the three mounting screws when it's right. Here's a view of a Quick Test page showing correct optical skew adjustment.
- - -
Laser Beam Deflection in the T650
The T650's printhead has no polygonal mirror and motor. Instead, it employs an oscillating mirror to deflect the laser beam. Here's a photo of it.
The mirror is right at the centre of that photograph. It pivots slightly on a vertical axis. An alternating magnetic field causes it to oscillate through the angle necessary for laser beam deflection.
# # #
# # #
