Repairing a Probe for the PMC MicroMag 2900 AGM
Above is a picture of the AGM probe. The sample carrier (quartz slide) can be seen on the right end of the probe. The quartz slide is attached to a thin polyimide tube that is itself attached to a piezo-like sensor to detect the deflection.
The quartz and the tube tend to break easily over time. Sending the probe in for repair is costly and therefore I sought ways to repair the probe myself.
- Broken parts (either quartz or tube) can be removed by using a heat gun to soften the glue.
- To replace the quartz slide I use a quartz cover slip for microscope slides (Alfa Aesar, 1.0×1.0x0.006-0.01 in). The single cover slip can be cut in 4×4 mm pieces by using a (silicon wafer) dicing saw.
- The tube can be replaced with a polyimide tube purhcased from Goodfellow (OD: 1.99 mm, Wall Thickness: 0.032 mm, ID: 1.93 mm, Length: 100mm). The tube needs to be cut to size and slots cut in at both ends (either parallel for out-of-plane, or 90deg rotated for in-plane) by using a Dremel rotary tool with attached cutting disc.
- I use Loctite Epoxy Heavy Duty as glue.
- A jig has to be made that holds the quartz slide in place while the glue hardens.
Unless the piezo sensor is damaged any probe should be repairable in-house with these instructions.