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The manufacturer's manual for the Retsch MM400 can be found here (in Retsch MM400 XRD Lab Notebook). Figure 10 shows the Retsch Mixer Mill.
Figure 10. Retsch MM400 Mixer Mill
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Each grinding jar for the Retsch mixer mill (Figure 11) has a main jar, a lid, a ball, and a white teflon spacer. Use the spacer to avoid damaging the agate (Figure 12). The inside of the jar and lid are lined with agate and the ball is of made of agate.
Figure 11. Agate grinding jars and ball.
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Place closed grinding jar horizontally in the clamps with the pin in open position. Verify the pin is in closed position (Figure 13) and tighten the clamps by turning the handle until the jar is securely tighten (hand tight is good). Close lid and select desired program to run.
Figure 13. Retsch jar clamp
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