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== Mounting Bracket ==
 
== Mounting Bracket ==
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The following hardware was built in preparation for the May, 2009 CHESS run.
 
[[Image:DiaMountBracket.png|frame|Exploded view of the mounting bracket with the diamond shown suspended on stretched wires.]]
 
[[Image:DiaMountBracket.png|frame|Exploded view of the mounting bracket with the diamond shown suspended on stretched wires.]]
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== Diamond Mounting Trials ==
 
== Diamond Mounting Trials ==
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[[Image:WireStretchTests.jpg|thumb|300px|Figure 1. Simple setup for testing wire stretching. Cap head bolts take the place of precise diameter rods that specify wire spacing. The ~5 g weight is shown on the right.]]
      
Simple wire stretching exercises were performed. The wire is approximated to be well past its elastic limit bearing 50 g weight. A thumb screw threading two washers going into a threaded stand-off (long nut) provided a nice 4.8 g weight that can clamp wire. So, a wire loop is created by clamping the ends of a wire segment between the washers by tightening the thumb screw.
 
Simple wire stretching exercises were performed. The wire is approximated to be well past its elastic limit bearing 50 g weight. A thumb screw threading two washers going into a threaded stand-off (long nut) provided a nice 4.8 g weight that can clamp wire. So, a wire loop is created by clamping the ends of a wire segment between the washers by tightening the thumb screw.
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[[Image:MBWireMarks.jpg|thumb|300px|Figure 2. Photo of a groove embossed by the clamped tungsten wire. (Numbers indicate mm markings)]]
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{| border="0" align="center"
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|- align="center" valign="top"
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| [[Image:WireStretchTests.jpg|thumb|200px|Figure 1. Simple setup for testing wire stretching. Cap head bolts take the place of precise diameter rods that specify wire spacing. The ~5 g weight is shown on the right.]]
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|| [[Image:MBWireMarks.jpg|thumb|250px|Figure 2. Photo of a groove embossed by the clamped tungsten wire. (Numbers indicate mm markings)]]
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|}
    
The tungsten wire was stretched using this weight and the shanks of cap head screws to keep the segments parallel. Playing with the first setup showed that the wire breaks quite easily and indeed, breaks before there is enough force to release it from the clamp of the bracket. The experience also showed that the wire is easily denatured (observed through kinks present even when stretched) so care must be taken in taking it off the spool and navigating around the supports.
 
The tungsten wire was stretched using this weight and the shanks of cap head screws to keep the segments parallel. Playing with the first setup showed that the wire breaks quite easily and indeed, breaks before there is enough force to release it from the clamp of the bracket. The experience also showed that the wire is easily denatured (observed through kinks present even when stretched) so care must be taken in taking it off the spool and navigating around the supports.
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[[Image:GlueTest_glass.jpg|thumb|300px|Figure 3. A square glass sample 12 mm on the side glued to the 20 μmm wires for practice. ]]
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{| border="0" align="center"
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|- align="center" valign="top"
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| [[Image:GlueTest_glass.jpg|thumb|300px|Figure 3. A square glass sample 12 mm on the side glued to the 20 μmm wires for practice. ]]
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|}
    
All following gluing tests were performed with the Supertacker 351 mentioned above. This adhesive turned out to be a bit too viscous for depositing on such thin wire. It did, however, match our other criteria very well. The trick for using it with these wires was to get inside tweezers and slide them gently with the wire in the opening of the tweezers. A somewhat sloppy layer is deposited on the wire that should still be quite tacky during the minute or so while a sample is deposited. In fact, it grips quite well upon first contact with a clean surface, such that alignment of the sample's edge with the wire is difficult.
 
All following gluing tests were performed with the Supertacker 351 mentioned above. This adhesive turned out to be a bit too viscous for depositing on such thin wire. It did, however, match our other criteria very well. The trick for using it with these wires was to get inside tweezers and slide them gently with the wire in the opening of the tweezers. A somewhat sloppy layer is deposited on the wire that should still be quite tacky during the minute or so while a sample is deposited. In fact, it grips quite well upon first contact with a clean surface, such that alignment of the sample's edge with the wire is difficult.
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|- align="center" valign="top"
 
|- align="center" valign="top"
 
| [[Image:DiaSize.jpg|200px|thumb|Figure 4. Photo of the diamond with a mm scale. It appears to be fairly precisely 4 mm]]  
 
| [[Image:DiaSize.jpg|200px|thumb|Figure 4. Photo of the diamond with a mm scale. It appears to be fairly precisely 4 mm]]  
|| [[Image:Wires_6-32.jpg|200px|thumb|Figure 5. Trial of stretching wires spaced by the shank of a 6-32 screw. The resulting spacing of 3.5 mm is just a little too narrow for our 4 mm diamond.]]
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|| [[Image:Wires_6-32.jpg|250px|thumb|Figure 5. Trial of stretching wires spaced by the shank of a 6-32 screw. The resulting spacing of 3.5 mm is just a little too narrow for our 4 mm diamond.]]
 
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| [[Image:DiaGlued.jpg|thumb|250px|Figure 6. The photo shows the diamond glued to 20 μm wires spaced by the minor diameter of 10-32 screws.]]
 
| [[Image:DiaGlued.jpg|thumb|250px|Figure 6. The photo shows the diamond glued to 20 μm wires spaced by the minor diameter of 10-32 screws.]]
 
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| [[Image:Dia_Yboundary.jpg|thumb|220px|Figure 7. A strange artifact, potentially challenging the notion that this is a mono-crystal. A slightly different lighting angle shows very flat surfaces (so these are not likely surface features.)]]
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| [[Image:Dia_Yboundary.jpg|thumb|220px|Figure 7. A strange artifact, potentially challenging the notion that this is a mono-crystal. A slightly different lighting angle shows very flat surfaces (so these are not likely surface features.) Photo orientation: left is the direction of the goniometer mounting rod.]]
 
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* twist ties
 
* twist ties
 
* ''recommended'': vice, 2" mouth minimum
 
* ''recommended'': vice, 2" mouth minimum
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== References ==
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* [http://www.xhuber.de/en/Products/diffractometers/xray/single_crystal/5020/5020.rsys Diffractometer at CHESS]
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* [http://zeus.phys.uconn.edu/~senderovich/GlueX/Diamonds/MountingBracket/DiaMountBracket_Shaft.pdf Diamond mount support post]

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