Functional Focuser

Lots of work over the last month even though there haven't been any updates.

The focuser now works. As you can see, the drive shaft of the GSO dual speed knob has been shortened so that the cap can fit flush to the drive block. (Thanks Jerry for lending me your vise.) Luckily this was a quick, easy hacksaw job as the steel wasn't too hard.

Several subtle tweaks have been required to improve performance. The diameter of the hole that holds the shaft on the far side of the focuser needs to be right, otherwise it slips at the extreme ends of the focus range. Adding the cap has improved this problem significantly as well.

The drive plate is made of aluminum. Turns out the continuous carbon fiber drive plate was still too flexible at the ends, resulting in a lot of slippage. For now, we sometimes still need metal.

Hopefully the next version fixes all the issues completely and a fairly heavy eyepiece can be used without slippage.

The next batch of prints comes Tuesday, including a continuous carbon reinforced draw tube, an improved filter cartridge, and the first print of the tertiary mount holder.

Lightest 2"-1.25" Adapter in the world?

The 2"-1.25" adapter has become a spinoff product. Tuesday's prints include a set of unit tests to determine whether we can do press-fit 2" filters on the bottom of the adapter. (So far, machined threads are far too expensive to add.) The minimal weight version of the adapter wasn't long enough to fit filters, and it wiggled a little in the drawtube because it wasn't long enough. Also, it needed more surface area to be in contact with the drawtube from the inside. So the 16 gram version was incredibly light but not entirely functional for general use. (Maybe this could be an option though for those who prefer ultralight over 110% function.) Let's see how much the longer one weighs. An average adapter comes in around 100g so this should still be a 75% weight savings. Also, this adapter will glow in the dark (obviously).

So the secondary/tertiary cage is almost completely designed. The only big component left to design is the heater/heat sensor cable hub.