Flat Surface Adapter -attach 1100 Mount or 900 Pier Adapter and Wedge to a flat surface (119FSA)

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The 8” Flat Surface Adapter (119FSA) allows the 1100GTO Mount and all versions of the 900 Mounts with their pier adapters to insert and be secured by the six 5/16”-18 screws. It has the same I.D. as our 8” Portable Piers, thus allows easy interchange between different mounting options.

The 119FSA is attached to a flat surface using eight 1/4”-20 screws to provide maximum payload strength (four screws will satisfy most setups). It also includes "N" and "S" engraving to ensure that the base of your mount will be oriented in the correct direction when it is inserted.

The Tripod Adapter is made of black-anodized aluminum and is precision machined to help guarantee a rock-solid platform for your observing and imaging needs.

900 (all versions) - special considerations
Use this adapter for these applications:

  • Interface between the Precision-Adjust Rotating Pier Adapter (900RPA) and the flat plate on your custom-made pier or tripod.
  • Although the Standard Pier Adapter (900SPA) can bolt directly onto the flat plate of your pier or tripod, you can use this adapter to give a more finished appearance.
  • Attach to the top of your 900 Hi-Lo Latitude Wedge (900WDG) if you wish to use the 900RPA.  This wedge allows the 900 mounts to be used at latitudes from zero to twenty degrees.  

800 Mount
This adapter is not suitable for the 800 mount.

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Specifications for attach to flat surface
The Flat Surface Adapter bolts onto the flat surface on the top of your pier or tripod. Your pier's top plate should be a minimum of 7.75" in diameter. The 119FSA itself is 8.375" in diameter. It adds 1.265" to the height of your mount.

The bolt circle for attaching the 900 Flat Surface Adapter to your pier is 7.230" in diameter. Please refer to the PDF link provided on the diagram above for detailed information on attachment preparation.

The holes for mounting the 119FSA to your flat surface are counter-bored to accept the head of standard ¼" socket head cap screws (13/32" or 0.406" diameter). This allows the 1100 base or 900 Pier Adapter to sit in the Flat Surface Adapter without interference. Because installations will vary, we do not provide the screws for mounting the Flat Surface Adapter to your pier or tripod.

Note: You may wish to consider purchasing our Flat Pier Plate with Flat Surface Adapter for 1100GTO and all 900 Mounts (119FSA-FP) if you are fabricating your own pier and need a flat plate to fit into the top. Some modification may be required to fit your pier I.D.

Mount the 1100GTO and 900GTO on the ATS 10" Portable Pier
We offer a combination two-part adapter (119FSA-10ATS) consisting of the 119FSA and 1612FP for customers upgrading their 1100 GTO and 900GTO Mounts for attaching directly to the 10” ATS pier. This provides maximum rigidity for imaging and large scopes.

Note: modification to the base diameter of the 1612FP may be required by ATS. The Control Box Extension (Q6281KIT) is then used to provide clearance for the larger pier diameter when mounting the control box (CP2, CP3 or CP4).

Fasteners included:
¼”-20 x ¾” Socket Head Cap Screws (8)