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Determination of the shape of very thin x-ray mirrors employed in spaced-based telescopes continues to be challenging. The mirrors shapes are not readily deduced to the required accuracy because the mount induced distortions are often larger than the uncertainty tolerable for the mission metrology. In addition to static deformations, dynamic and thermal considerations are exacerbated for this class of mirrors. We report on the performance of one temporary mounting scheme for the thin glass mirrors for the Constellation-X mission and prospects for deducing their undistorted shapes.Keywords: x-ray telescopes, Constellation-X, mirror mounting, optomechanics INTRODUC TIONX-ray astronomy is limited to space-based observations. Traditionally this, in turn puts severe strain on either the entendu of the telescope (Chandra) or the resolution (Suzaku). In fact, neither trade is desirable from the point of view of the x-ray astronomer. On the other hand, many compact objects such as the event horizons of black holes are too small to be imaged by even the best modern telescopes. Given these objects cannot be resolved, the resolution needed by an x-ray telescope then can be rather modest by optical telescope standards for resolving other point sources from one another.The grazing-incidence nature of x-ray telescopes greatly reduces their collecting area. As a result, an x-ray telescope is in fact a number of nested, confocal telescopes. The number of confocal elements and their individual areas sets the collection area. To make this as large as possible and still be within the payload limits of the launch vehicle, most x-ray telescopes consist of very thin shells. This comes with a penalty that their fabrication is difficult and often imprecise and they are easily distorted when mounted. This second penalty can away in theory while orbiting but since gravity distortion is present during terrestrial assembly, usually not completely.Additionally, the component fabrication process is uncertain because of the distortions present during metrology either results in incorrect processing (surface correction) or unacceptably large uncertainty in the quality at the component level. It is this metrology mounting problem that we address here.There are two basic approaches to the mirror mounting problem: 1) Make a mount that distorts the mirror much less than the metrology requirements for the mirror, or 2) Make a mount whose distortions are repeatable and predictable to sufficient degree that they can be removed from the measurement. We have opted to pursue the second approach although the distortions cannot be too large for them to be repeatable.