fourth — and final — pulley is inserted into the other Z axis
channel at the same height as the motor/pulley subsystem.
Once all of the pulleys have been installed, a two foot
length of timing belt is snaked around them in one Z axis,
and connected to each belt mount on the trolley. One of
the belts has been installed in Figure 10. This same
procedure is repeated for the other Z axis channel. Figure
11 shows the trolley suspended between the two Z axis
channels.
6. X-Y Axis Mount. Pillow block bearings are used for
suspending the X-Y axis trolley from the printer’s frame. A
combination of tubing and beams enable the block
bearings to slide the 3Doodler in both the X and Y
directions. The X axis bearings have been installed in Figure
12.
7. X-Y Axis Trolley. Rather than being pushed and
pulled along by belts, the X-Y axis trolley scoots along on
two sets of geared rack and pinion drives. These racks are
independently attached to the pillow block bearings. Two
stepper motors are used for driving the pinion gears along
58 SERVO 05.2015
X-Y Axis Mount
Parts List
4 - Aluminum channel 12"
4 - Dual channel flat bracket
4 - 6-32 tapped stainless steel screw plate
.770 x .770 (square)
4 - Channel connector plate A
32 - Socket head cap screw 6-32 3/8"
2 - Aluminum beam 11.935"
12 - Socket head cap screw 6-32 1/2"
12 - Nylock nut 6-32
Z Axis Trolley Mount
Parts List
1 - .250" to 3 mm set screw shaft coupler
#625116
8 - Socket head cap screw 6-32 3/8"
1 - Stepper motor SFE ROB-10551
1 - Aluminum channel 4. 5" #585444
1 - Dual channel flat bracket
2 - 16T .250" bore timing pulley
3 - 1/4" x 1/2" flanged ball bearing
3 - 1/4" bore aluminum collar
2 - 2.375" x .250" OD stainless steel
D-shafting
1 - Channel connector plate A
1 - 6-32 tapped stainless steel screw plate
.770 x .770 (square)
4' - 3/8" width 1/5 pitch XL timing belt
#615412
X-Y Axis Trolley
Parts List
4 - Aluminum beam 11.935"
4 - Beam gear racks #615410
8 - 90° dual side mount #585470
8 - .625" pillow block #535162
8 - Socket head cap screw 6-32 3/4"
8 - Socket head cap screw 6-32 1/2"
8 - Single screw plate
8 - Nylock nuts 6-32
2 - Dual screw plate #585472
1 - Aluminum channel 1.5"
3 - Single channel 90° angle
1 - Dual channel flat bracket
1 - Flat bracket B #585584
8 - Beam bracket T #585656
2 - Stepper motors with four M3x10 mm
bolts
Figure 8. The underside of the Z axis trolley.
Figure 9. Lower the Z axis trolley down the Z axis.
