Automounter



PLEASE NOTE: YOU MUST USE THE PIN BASES SPECIFIED BELOW. Other pin bases may not work in the ALS beamline automounters.


Contents

[edit] Introduction

The Automounter is an automated cryogenic crystal mounting system that is aimed at high-throughput macromolecular crystallography by increasing experimental efficiency and reliability. Automounters are available on beamlines 5.0.1, 5.0.2, 5.0.3, 8.2.1 and 8.2.2.

The automounters consist of a robotic arm to place pins on the goniometter, and a dewar to hold the crystals, where they sit in "pucks":

The robot arm, or "gripper", reaches into the dewar and picks up crystals one at a time to mount them on the goniometer at the beamline.


THE 5.0.1, 5.0.2, 5.0.3 ROBOT:

THE 8.2.2 ROBOT:





[edit] Arrangements for Use

Approximately 1-2 weeks before your scheduled beamline time you will be contacted by our administrative staff. At this time you need to indicate whether you are interested in using the automounter. All users must be trained on the automounter prior to use. Beamline staff will conduct training at the beginning of your scheduled time. Before you can use the automounter you will need to obtain your own set of pucks and puck tools, detailed section below.




[edit] Equipment Required

The automounter requires: (1) pucks, (2) the associated puck tools, (3) specially sized bases and pins of a certain length. Crystals will need to be pre-mounted in the pucks prior to arrival.

1. PUCKS

The 5.0.1, 5.0.2, and 5.0.3 robot takes both the ALS-style pucks and Unipucks. These pucks hold 16 pins each, and there are 12 puck slots in the robot dewar. 5.0.3 can accept 6 pucks in the dewar at this time.

ALS pucks:

Unipucks:


The 8.2.1 and 8.2.2 Rigaku robots take the ALS-style pucks, the Unipucks, and the Rigaku-style pucks. The Rigaku pucks hold 12 pins each, and there are 5 puck slots in the dewar.


Rigaku pucks:


2. PUCK TOOLS


The ALS pucks and Unipucks require puck tongs (used for holding pucks or transfering pucks from dewars), a puck pusher tool (used to load pucks into the dewar at the beamline), a puck wand (used to put the lid onto the puck), a puck separator tool (user to remove the lid from the puck), and a shipping cane (used to ship pucks to/from the beamline).


ALS Puck and Unipuck Tools:

From left to right: bent puck tongs, straight puck tong, puck pusher, puck wand, puck separator tool.

The Rigaku pucks require the ACTOR pin tongs (used to load pins into pucks), the ACTOR pin check (used to check that pins are seated correctly in the pucks), the puck tongs (used to load the pucks into the dewar at the beamline), and the ACTOR shipping cane (used to ship pucks to/from the beamline).

Rigaku Puck Tools:

From top to bottom: pin tongs, puck tongs, pucks, shipping cane.


4. BASES

The bases that are recommended to be used in the BCSB automounters are the Hampton Part Number HR4-779 "Crystal Cap Magnetic ALS" or the Mitegen GB-B1A. Spine bases (CrystalCap HT) do also work.

Note that these bases are different from the bases used in the SSRL automounter:

Left: SSRL base, Right: ALS base.



4. PINS

The only length of pin that can be used with the BCSB automounters are "Hampton 18 mm" pins (this corresponds to breaking off the two end segments of a Hampton pin) and "Mitegen 18 mm /SPINE" pins.

The dimensions are fairly critical here, and the most important one from the automounter's standpoint is the distance from the inside mounting surface (which corresponds with the top of the goniometer magnetic mount) to the center of the crystal = 20.3mm ± 1mm.

It appears that the SSRL-style pins with the copper stem do not work well with our off-axis coldstreams. They work OK after an initial mount of the crystal, but subsequent dismount/remounts seem to result in excessive crystal warmup.

Hampton pins:





[edit] Loading pins into Rigaku pucks

For the Rigaku pucks, you can use the bent cryotong to load the pins as shown below. Care should be taken to insure the pin is in contact with the base before releasing the cryotong:

In this picture, there are pins sitting in positions 1 through 6 of the puck.

Alternately, you can load Rigaku pucks using tweezers to put the entire base and vial into the puck. Just be sure to let the staff know that the caps are still on the pins, so they can remove the caps before placing the pucks in the robot dewar.

Check Your Pins: It is very important to check the seating of your pins when using Rigaku style pucks. The easiest way to accomplish this is to visually inspect the puck by lifting the puck top above the liquid nitrogen level and shining a flashlight on it. This provides a clearer view into the base of the puck and should allow you to see any improperly aligned pins. If it is difficult to see the pins, look for symetry in the reflectivity of the pins. A tipped pin will often look shadowed and asymetric. In the following photo, pins 2,5,8,9,11 and 12 are improperly mounted:

If a pin is tipped over the easiest and safest way to reseat it without harming your crystal is to use a straight probe about the diameter of a wire coat hanger to reseat the pin by gently pushing on the top of the pin base opposite to which the pin is leaning. The pin should "snap" firmly onto the base when straightened. The ACTOR pin check tool can also be used, but a visual inspection is preffered and generally more reliable.

[edit] Loading pins into ALS or Unipucks pucks

The NSLS has made an excellent video on how to load pins into the ALS pucks and Unipucks. It can be found here:

http://www.px.nsls.bnl.gov/robot/robot_video.html


For getting the pins back out of the ALS pucks, you can use the puck separator tool. First, under LN, place the puck in the separator holder as shown:

Then, insert the puck separator into the base:

And press down:

The pins will be left in the cap, and can be removed with a magnetic cryowand:


[edit] Things to Watch For

The ALS and Unipucks have small clips holding the base to the cap. It is important to make sure these clips are secure but not protruding.

if the clips are bent out, it is very difficult to get the shipping cane in or out of the shipping dewar.

if the clips are very loose, there is the danger that the puck base will fall out of the cap during transfer from the shipping cane to the robot dewar.

Replacement clips can be purchased from Crystal Positioning Systems or fabricated according to the drawing below.


The ALS style pucks are also susceptible to a thermally induced degradation of the ferrite which holds them to the dewar base plate. CPS also sells replacements for these.

[edit] Further Details on the sector 5 Robot Use

Robot safety and specifics for the sector 5 robots are described here.


[edit] Technical drawings and CAD models for the pucks and automounter tools

In the interests of maintaining the widest possible operational compatibility between different implementations of the Berkeley Automounter robot system we are making publicly available a full set of drawings and CAD models for the pucks, handling tools, and shipping accessories. These can be freely downloaded below. Please report any errors or omissions that you find back to BCSB so that we can revise the drawings appropriately.


step_format_ALS_stlye_puck_models.zip
step format drawings of the ALS style pucks, uploaded Jan. 11th 2011

PDF_format_ALS_style_puck_drawings.zip
PDF format drawings of the ALS style pucks, uploaded Jan. 11th 2011

Step_Format_Tool_Models_V1.0.zip
V1.0 of the tools and shipping accessory models, uploaded Jan 20th 2010

PDF_format_Tools_Drawings_V1.0.zip
V1.0 of the tools and shipping accessory drawings, uploaded Jan 20th 2010


[edit] Ordering

The Rigaku pucks and puck tools can be ordered from:
http://www.rigaku.com/automation/actor-tools.html

A 2008 pricelist can be found here: Rigaku tools pricelist

Unipucks, ALS Style Pucks, shipping canes, and puck tools can be purchased from:
http://www.crystalpositioningsystems.com/
The Unipuck tools are the same as the ALS puck tools.
(Note that they are called "V1 Unipucks" on the Crystal Positioning site.)

Bases can be ordered from either of the following suppliers:
Hampton Research http://www.hamptonresearch.com)
HR4-779 "Crystal Cap Magnetic ALS"
or
Mitegen http://www.mitegen.com/products/bases/bases.shtml
Part Number GB-B1A

Pins can be ordered from Hampton Research or Mitegen. They come in a variety of sizes. Sample Hampton part numbers are HR4-993 (10 micron loops) and HR4-941 (20 micron loops. Sample Mitegen part numbers are M1-LSP-50 (50 micron aperture MicroMounts mounted on 18mm pins) and M5-LSP-20LD (20 micron aperture MicroLoops LD)

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