How To Clean The Spinner Turbine On The Room Temperature Shim Assembly

The Room Temperature Shim Assembly is the colored tube, that goes down into the bore(center) of the magnet. It is separated into 2 parts. The upper shim stack(on newer systems called the BST-Bruker Sample Tranport), this is where you insert your spinner with sample at the top, and has the spin optics sensor, spin and lift air hoses. The lower part which has the actual room temperature shim coils and the spinner turbine where the sample in the spinner sits and when the spin button is enabled, allows sample to spin. Once sample is spinning, the optic sensor at the bottom of the upper shim stack(or BST) detects how fast sample is spinning(on new systems as well, the BST can detect whether the sample is up, down or missing). If your sample is not spinning, and you have tried lowering the probe out of the bottom of the shim assembly 4" (while spin air is on) and have made sure your sample depth is set correctly and you have spin air going to the upper shim stack, you will need 2 people to properly do the following:

1) You will need to turn the heater off on the variable temperature unit. Take sample out of magnet. Once the heater is cool, take the heater out of the probe. Then remove the thermocouple out of the probe as well as the gas air flow nipple and clamp or LN2 transfer line.

2) Take a sharpie marker, and mark the orientation of the probe to the bottom plate(where the probe screws up into the room temperature shim assembly) of the room temperature shim assembly.

3) Loosen the 2 brass screws, that screw up into and support the probe into the shim assembly, and remove probe.

NOTE: Where you insert spinner with sample at the top of the upper shim stack(BST), you will see 3 flat head screws. These screws are 3-4ft long, but are threaded only 1". You also will see an orange collar, that fits around the upper shim stack and has 4 hex screws, which secures this to the top of the magnet can. The collar also has 1 or 2 hex screws on the side of collar, to secure the position Z-CENTER, so this shim stack doesn't slide down to an inappropriate Z-CENTER position. You may or may not see this exact type of collar, on the underside of the magnet. This collar secures, the bottom room temperature shim assembly, to the underside of the magnet.

4) One person can hold the lower shim assembly, and mark the orientation of the lower shim assembly to the bottom of the magnet, with a sharpie marker. If there is a collar on bottom of magnet, you can take a sharpie marker and mark the orientation of the collar, to the underneath of the magnet.

5) The other person can go to the top of the upper shim stack, and loosen the 3 flat head screws, where you insert the spinner and sample. Remember, these screws are 3-4ft long, and are threaded only 1". DO NOT REMOVE THE TOP COLLAR, WHICH SUPPORTS THE UPPER SHIM STACK OR ROOM TEMPERATURE SHIMMING WILL BE GREATLY AFFECTED!!

6) If there is no collar to support lower shim assembly, once these screws on top are loosened, you will start to feel the lower shim assembly slide down. If there is a collar on the bottom, you can take your non-magnetic allen head wrench and remove the 2-4 allen head screws, only, that secure the lower shim assembly to the bottom of magnet. DO NOT LOOSEN OR REMOVE THE SIDE ALLEN SCREW ON THE BOTTOM COLLAR!!

7) Once the lower shim assembly is lowered out of magnet, check with a flashlight and looking up from the bottom of the bore of magnet, make sure the 2 black orings( on BST there are 3 reddish orange orings) are still present on the underneath of the upper shim stack. These O rings are important! This creates a seal for the bonding of the upper and lower shim assembly for the spin and lift air to work properly. You will need to put a cork or foam or cardboard(anything non-magnetic)to cover the exposed bottom of the center bore of the magnet! This way magnetic materials will not go up the bore tube in magnet.

8) With the room temper shim assembly out, on the top you will see the spinner turbine housing(where the spinners sits and you will also see the spin air jet holes are, which allows spinner to spin. You will need to mark the orientation, with a sharpie marker, the turbine to the side of the shim assembly. Remove the outer 3 brass flat head screws. These screws secure the spinner turbine housing to the top of the room temperature shim assembly. You should be able to remove this turbine housing now and hold it in your hands. NOTE: ON A BST STYLE SHIM ASSEMBLEY DO NOT REMOVE THE SCREWS THAT SECURE THE SPINNER HOUSING TO THE LOWER SHIM ASSEMMBLY.

9) Take the spinner turbine housing, and clean the inside and outside of the turbine assembly with methanol. DO NOT USE ACETONE! You will also need to use a very fine wire, dipped in methanol, and clean the jet holes, to make sure these holes are not obstructed.

10) Once the spinner turbine is completely clean and dry, reinstall spinner turbine and realign orientation marking and screw the 3 flat brass screws back into place.

11) Remove the foam, cork on the underneath of magnet and insert shim assembly up into bore of magnet. Align orientation markings of collar or if no collar(however you marked it), and hold shim assembly in place.

12) The person on the top of magnet, should see all 3 long flat head screws stick up slightly, if the bottom shim assembly is properly orientated. When this is done, tighten screws snugly. DO NOT OVERTIGHTEN SCREWS!

13) The person on the underneath of magnet, can reinsert the allen screws to the collar and screw them to properly secure the collar to the underneath of magnet.

14) Reinsert probe and align the orientation marking. Screw the probe in place. Reinsert heater, thermocouple and gas flow nipple and clamp or LN2 transfer line.

15) Insert sample into spinner, make sure sample is at correct depth(i.e 5mm). Push lift air button on, insert sample and release lift air, to lower sample. Wait 30 seconds, push spin on button. Sample should spin to correct rate(i.e 5mm should spin to 20). You should now be ready to go aquire data!

VERY IMPORTANT NOTE: If you have the newer style room temperature shim assembly for the bsms(has the 2 separate cable for the SCB7M and SCB13R for BOSS1 or SCB13L, SCB13M, SCB13R(3 separate cables) for BOSS2), DO NOT REMOVE SPINNER TURBINE mentioned in step # 8! Just leave the spinner turbine assembly in place and clean the spinner turbine and the jet holes with methanol.

If sample, still does not spin, contact Bruker Center Console Support.