I’m sure that many of you will have come across the same frustration that I used to have – I’d set up my ’scope (a 6” Fullerscope newtonian) for my first object, all nicely balanced and with finder and eyepiece conveniently positioned at or near the top of the instrument. Then I’d decide to move on to some other object, and find that the orientation of my equatorially mounted ’scope now meant that I had to rotate the tube to bring the finder back to a convenient position. I never seemed to remember to bring the scope to the horizontal before doing this, and not unsurprisingly I found that as soon as I loosened the tube rings, the scope slid downwards and I lost the careful balance I’d previously established.
Apart from doing it right to start with there is a fairly straightforward solution. In ‘the old days’ it was possible to buy a tube strap for one’s telescope, but seemingly not so today – so what to use as a substitute? The first thing I tried (on a 6” Fullerscope Newtonian) was a pair of large, rubber tree-ties linked together and tightened round the tube at the point above the upper hoop ring. This did quite a good job of stopping any sliding, but I then discovered an even better solution – an embroidery hoop!
These are to be found in your local sewing shop, and come in several sizes, and are made of either plastic or wood. I could not find one of the exact diameter I wanted, so the wooden variety allows the hoop to be easily shortened by just removing the screw clamp, cutting off an appropriate length and reattaching the clamp. Stick a length of foam rubber draft excluder to the inside, and you have an excellent marker that will always ensure that your telescope remains in perfect balance throughout the evening. This was done first for my old Fullerscope reflector, but I then did the same for my 5” Skywatcher refractor; I still have and occasionally use this latter ’scope, the original embroidery hoop is still in place and work fine to this day. Anyone for embroidery?
The photos show my Skywatcher 120mm Evostar, with the close-up showing the embroidery hoop resting against the dovetail and tube rings. The green velcro straps are just keeping tidy the cable for the dew heater. If anyone visits the shop and showroom of Altair Astro in Norwich, then they’ll see my former 6” Fullerscope which they have refurbished and put on exhibition as a fine example of early UK telescope making.
By John Axtell
Feb 2024