Dr_Ju_ju

You'll pay a lot more than the cheap Fotek ones, but reliable component suppliers do stock them e.g. https://uk.rs-online.com/web/p/solid-state-relays/7150846/ or https://uk.farnell.com/opto-22/380d25/relay-solid-state/dp/1653772

If you are getting layer cohesion issues, I'd suggest you'd check the settings in your slicer to ensure that your vertical shell perimeters and infill\perimeter overlap is adequate.... What I find, is that, over time, and with overnight cooling & daytime heating, I'll get a 'sag' in longer parts, but other than that, no issues.

Wishful thinking ?? 🤔

Need some more info, i.e. what make scope\mount\tube-rings? & accurate dimensions (tube ring screws are usually UNC thread), type of handle you require, e.g. only for carrying or more of an additional mount for ancillary equipment. Also where are you located , as it may well a number of iterations....

If you can, under the grids, dig some 50-100 mm trenches, top to bottom & fill with gravel, that should give you enough drainage.

How old is the camera?, as I've never seen it....

I'm using the MyPocuser Pro by Robert Brown, https://sourceforge.net/projects/arduinofocuscontrollerpro/files/, (i.e. same as James is currently documenting)

I'm currently building one for the same purpose, and so re-using the control\driver electronics, so I've gone for a Nema 14 PG27 from OMC Stepper online. They may not have UK stock, but there are usually some in the German warehouse....

Many of Photoshop plugins work.... see https://www.namesuppressed.com/support/plugins-affinity-photo.shtml

Don't worry too much about the buzzer, you will only hear a beep on start up, else it doesn't do anything...

On most 'quality' multimeters, the continuity mode is usually also the diode check mode, which usually mean a potential difference of approx. 0.7volt for the forward current, so they tend not to be over 1-1.5 volts max, so very unlikely to do any damage to the circuit..... Now, my dedicated continuity tester on the other hand, is a lot more robust & uses 9 volts, but then it is designed for testing long distance circuits.....

If not already done so, unplug the Nano from the board & connect it to your computer & flash the latest version of the firmware to it, using the Arduino IDE. I use the latest version, 1.8.11, but you have to set Tools \ Programmer - Atmega328p (Old Boot Loader). At least then you'll have more confidence that you at least have a working nano....

How are going to connect to it ?? personally I'd go wired (GB Ethernet) especially if you are going to be transferring large volumes of data... How many USB ports (2 & 3) does it have ?, as you may well need more for focusers, filter wheels, cameras, mounts etc.... Then consider mounting it, I site computers\hubs adjacent to the mount, & not on the mount adding to the payload weight....

Try a Torx 'Star' bit of the right size

You could but one of these & modify as needed https://www.ebay.co.uk/itm/POWER-SUPPLY-MAIN-CHARGER-FOR-Canon-ACK-E10-ACK-E-10-EOS-2000D-4000D-1100-D/283588662482?hash=item42073394d2:g:2YwAAOSw9yldUQ4H

Why not form a path with some plastic lawn edging, that can be pushed into the soil, or staked in place, in-filled with weed control membrane, & then filled over with gravel ??

Have you contacted Juan ?? I've always found him very approachable ....

If you have more nuts\washers of the correct size, then you could probably do away with the springs altogether by locking the parts together. Think of the thread as fixed pillar, that you can run the bed up-down on and lock in place... It's how I fix the beds on my printers. It takes longer, with repeated levelling routines, but once adjusted, with everything tightened up, it usually doesn't need further adjustment for a long time.

If you have a Pi, why not install the AllSky software & give it a go, the ASI cameras 'tested' cover a wide range, so I suspect your Altair cameras will work ok....

As Vlaiv, has stated, a decent stepper motor with appropriate drivers, combined with micro-stepping, will easily do what you want.... If you want further info on a 'home-built' system, then have a look at Tom Carpenter's excellent AstroEq system (https://astroeq.co.uk/tutorials.php). I use this system to convert a non-goto EQ5 system to a fully remote controlled system, with all adjustments to rotation etc., being done in software\configuration.

If you already have the connectors\crimper, then buy some of this (https://www.ebay.co.uk/itm/External-Outdoor-Cat5E-FULL-COPPER-Network-Ethernet-Cable-FTP-UTP-Reel-Lot-Cat5/381837841197?epid=14001991729&hash=item58e74f132d:m:mwQOmL3g59EZPfeqt8CT6tQ) At 50m for £16, which to my mind, is a no brainer, you can just tack it to the side of fence panels etc. then forget about connectivity issues.

Just be aware, that there are many bad copies of the DS18B\S20 series of devices. To ensure you get pukka ones you need to buy from a reliable distributor, i.e. RS Components, Farnell etc....

Astroberry is based on Raspian Buster, while the Polemaster software requires Ubuntu Mate, which is what I've got installed\running on a Pi4, so I don't think it will work ok, but I may well be wrong ....

If you've ordered the board from Aisler.Net (Germany based) then they usually only take a few days to come.... As for the temperature probe, I use variants of these DS18B20's e.g.https://www.ebay.co.uk/itm/DS18B20-Waterproof-Digital-Sensor-Thermal-Probe-Temperature-Thermometer-Arduino/111431573979?epid=1386221694&hash=item19f1d6e1db:g:ekwAAOSwxH1T5i~D They are simple 3 wire probes, which I wire up using 'stereo' headphone plugs & chassis sockets...

Sorry Derek, I should have waited to your confirmation, but I just finished packing the trailer, for a trip up either Sat\Sun, and was sorely disappointed....