Polaroid SX70 manual Mirror Cover / Boot Assembly, Front cover light shield cam

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Figure 4-6 Front cover light shield cam

When a new type shutter is installed, the cam in the light shield must be inspected and changed if necessary. The new cam should be installed in the same place and manner as the old cam (Figure 4-7). Remove the old cam uising an x-acto knife to cut the plastic rivets. Place the new cam in the same position, making sure the cam lip goes over the edge of the light-shield as shown, and the pins through the four holes. When assembled, apply heat enough to peen over the ends of the pins projecting through holes - thus staking the unit in place.

If new cam are not available, it will be necessary to install a new front cover assembly.

B. MIRROR COVER / BOOT ASSEMBLY

The mirror cover assembly consists of the mirror cover, the boot, and the viewing mirror. Because of its construction, ti is not feasible to disassemble the mirror cover assembly itself and, therefore, whenever one of its major components fails the entire assembly is replaced. The mirror cover could sustain damage in the form of cracks or broken hinges, or overall distortion. The boot could be cut, torn and damaged by wear. The mirror could be loose or displaced in its mounts, broken, or its surface damaged beyond cleaning. Should any of these faults be evidenced, replace the assembly.

NOTE : On older cameras, a coding system is used to match Fresnels and mirror covers. When changing mirror cover and Fresnel assemblies, correct color coding must be employed to prevent unacceptable tolerance buildup. This is usually demonstrated by difficult cloding the camera, etc. The chart below shows the color codes to be used : a red coded Fresnel goes with either a red, yellow, blue or white mirror cover; not with a green mirror cover. The choice should be the first in order of the chart. Red first, yellow second, etc. The color code is located on the mirror cover, on the underside, upper right-hand corner, viewed as if holding the camera to take pictures. On the Fresnel assembly, it is marked on the protective paper at the point where the adhesive seals the paper around the Fresnel.

COLOR CODES USED WHEN CHANGING

FRESNELS AND MIRROR COVERS

MIRROR COVER

Fresnel

Red

Yellow

Blue

Green

White

 

 

 

 

 

 

Red

x

x

x

 

x

Yellow

x

x

x

x

x

Blue

x

x

x

x

 

Green

x

x

x

x

 

● Black

x

x

 

 

 

Newer cameras employ a universal Fresnel/ Mirror cover assembly. No matching of coded parts is necessary.

Figure 4-7 Replacing light shield cam

Removal

1.Erect the camera to picture-taking configuration.

2.Open and remove the front cover.

3.Remove the decorative leather covering from the bottom cover.

4.Remove the four bottom-cover retaining screws.

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Contents Page Page General Description DescriptionOpening the Camera Camera OperationStarting the Automatic Mechanism Loading the Film packViewing and focusing Setting the exposure counterViewing and shooting Developing the print Exposures using flashCompleting the film pack Closing the camera Shutter Description Ambient Light Mode11 a Location & Arrangement of internal parts Shutter Description Flash Mode Page 14 S5 being opened by the recock ram Gear train Page Introduction Power SourceLens Viewing and Exposing SystemViewfinder optics exposing Fresnel Figures 2-3 a and 2-3 BFresnel screen Mirrors ViewfinderFlare baffle Camera Elctronics 1. GeneralSX-70 Switch locations Switch functionsS3 Being opened by recock ram S4 Switch operating configurations Function Sequence Switch Function TablePage Flash Timing Sequence Chart Shutter, exploded view Shutter Mechanical Details FigureA Solenoid S2 operation Sequence of Operations Film Processing ComponentsPage Max Introduction Initial Tests III TroubleshootingSX-70 Cmaera Repair Inspection Procedure Test Equipment Operation Power supply and pack simulator FigureLocation of new collimator target Collimator FigureDisengaging the idler gear Comprehensive tester Comprehensive Testers -6Model B Camera tester Model B Camera Tester Light Leak Tester Figure Comparalumen Light Levels TableLight leak test system Flash Simulator Board Figure10 Manual camera tester Manual Function Tester FigureManual Function Test Sequence Exit Pupil Test Optical System13 Aligning the exit pupil gage Entrance Pupil TestConcave Mirror Distortion Check USE of Analysis ChartsFresnel Quality Check Collimation16 Fresnel standards chart 18 Flex circuit terminal locations Camera/Shutter Isolation19 Test points on SX-70 shutters Camera Analysis ChartsPage Removal Front COVER/SPREAD Roll AssemblyInstallation Front cover hinge studs Repairs / Adjsutments Loose Front CoversBending the stop latch Replacing the Light Shield Cam Interference Between Front and Bottom CoversTop Spread Roll Looseness Front cover light shield cam Mirror Cover / Boot AssemblyBoot retaining screws