For us living in Poland @ 52 deg N, most mounts have the annoying property of balancing around the polar alignment altitude (pole elevation) axis. When used on lower latitudes, the center of mass of the mount with scope and counterweight is placed north of the altitude axis and therefore the mount mass presses against the altitude adjustment screw - essentially taking off any backlash and making polar altitude adjustment precise and responsive. When the mount starts to balance, the center of mass moves towards south and instead of pressing against the altitude adjustment screw, it actually forces the mount in the opposite direction. In such situation, one needs to keep one's hand on the counterweight shaft and press the mount back against the adjustment screw. Precise polar alignment starts to be hard to achieve.

Few mounts have the altitude adjustment arranged in a form of two push-pull screws.

While some people may say that I have committed sacrilege, I have decided to modify my AP400 mount to add the push-pull adjustment. For this modification, I had to remove the equatorial head from the fork, dismantle (and clean) the fork. Next, a small piece of 10x10mm aluminum bar was attached to the movable part with 2 M4 stainless steel Allen bolts. A piece of the same 10x10mm bar was attached to the fork arms, again using M4 stainless steel Allen bolts. It has M6 threaded hole, which holds M6 brass "push" screw with black plastic knob. After all holes were carefully measured, drilled and tapered, I have re-assembled the mount base adding small amounts of quality grease between the moving surfaces.

The result is - well - amazingly easy and precise polar alignment in Poland. When I travel to more southern locations, I can simply unscrew two Allen screws and remove the 10x10 bar with adjustment screw.

I do highly recommend this modification to anyone using AP400 mount beyond latitude 50N or S.