Testing the balance and tracking.

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After lunch I continued tracking the sun and checking the slewing. There no complaints from the stepper motors now that the system is balanced.

The image [right] shows the first folding mirror of my 7" refractor. Both mirrors have protective plastic food storage tubs covering them when not in use. Both mirrors are "water marked" from repeated dewing in use. Any serious dewshield would need to be offset, or oval,  to avoid vignetting. I am unsure how useful the black cloth I bought for a potential shroud would obviate dewing. Even the back of the objective used to dew up in use. One of the reasons I preferred the straight tube arrangement. Perhaps I ought to try the long tube version on the new mounting.

Note the mirror's greatly enlarged support and collimation triangle with fixed apex point. This provides stable and "slow motion" adjustment to the mirror in all planes. I have now added an aluminium stray light exclusion tube with end baffle in place of the earlier cardboard one. The focuser and tube rotate in the back plate against PTFE rings, inside and out, for smoothness. An earlier metal to metal version was hopelessly sloppy and often very difficult to turn due to friction.

It feels rather sophisticated to have four speeds available to Slew, Move, Center and Guide. Far more useful and predictable in effect than a variable speed [VFO] synchronous system like that on my the Fullerscopes MkIV. Even using my lowest power, 32mm eyepiece @ 68x the Slew almost whips the image out of the field of view. Move, Center and Guide each offer reduced speeds in consecutive order. No doubt their efficacy become increasingly important with increased magnification or when imaging.The IH2's helpful little screen shows which drive or control rate has been chosen.

The next image [above] shows a nearer view of the folded refractor pointing at the zenith with the Dec axis horizontal. I have doubled the aluminium, channel section saddle. The two halves are pressed back to back by the large ring of clamping screws of the Tollok bush. Each end of the saddle is also clamped together by the crossbar fixing bolts.When the temperature is more suitable I shall epoxy the two channels together int an I-beam for greater stiffness. The plywood crossbars can be replaced by stiffer metal components when I find suitable materials. The crossbars could even be fixed inside the framework to reduce overhang.

The OTA can be safely rotated 360 degrees right around the Polar Axis with the Dec axis at the correct angle. Allowing a "weights-up" horizontal parking position if so desired. This places the OTA at its lowest possible condition to avoid high winds. It also requires the minimum cover height or size of tarpaulin. Though I would much prefer a more permanent solution once the raised platform is completed. Either a roll off cover or a cylindrical observatory would be preferable for rapid deployment and much greater protection.

This last image shows the AWR electronics sitting on the pier shelf. Thanks to the latched plugs and sockets, on all the leads, the electronics can be quickly and easily removed to safety. Leaving the stepper motors and their cables fixed in place.

I want to mass load the base of the slotted angle pier/stand to see if it helps stability in windy conditions. At the moment the stand is resting on blocks of scrap aluminium or wood for leveling on the uneven ground. Not an ideal arrangement, but I'm hoping to raise the platform long before the stand starts rusting. Famous last words!

I found somewhere out of sight to hide all the potential telescope making tubes. These have been adorning the side of the back yard/parking space for ages. Often spoiling the backgrounds of my ATM images. It would help if I could get rid of the car too!

Click on any image for an enlargement.

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