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Questions on a new build planning

Sebastian
 

Hi all,
My very first message, finally.
As a brief introduction, I got a SW 200/1000 on a non-tracked NEQ5 for visual and AP a few months back. I quickly noticed that the possibilities in astrophotography were much more limited than I first thought without tracking, so -being a DIY person, and after evaluating several different approaches- here I am.
I've been digging into the different threads and posts on this group for weeks now (and I'm impressed by the quality of most discussions), and I'm well into a potential shopping list. 
 
My layout -and questions below- would be:
 
Telescope / mount / photography:
- SW Explorer 200p over NEQ5 mount
- Nikon D80 + a borrowed D3300 for DSO's, and a modified Logitec C270 webcam for planetary and the moon
 
OnStep potential setup:
- Arduino Mega2560 
- MKS-Gen L v1.0 
- Nema 17 motors, 0.9deg, 0.9A (*)
- LV8729 drivers (**)
- Timing belts and pulleys, 2.5:1 - GT2 16T/40T (***)
- HC05 BT + ESP-07 WiFi
 
(*) The options I'm considering are Stepper Online vs. Oriental Motor. The Oriental's price is 4x Stepper Online's, which translated to my currency is really a lot of money. The question is: what are the differences that I would notice between both of them?
 
(**) This is the item where I spent the most reading-time on. I started with DRV8825, then considered TMC2209, then disregarded both for LV8729 after a Howard's post, then read about TMC2100 and 2130 (with this later one considerations included). I would think that FYSETC TMC2130 v1.1 with SPI enabled is a good choice (like this one from Amazon), but I'd like some inputs on this if possible. Any "magic" recommendations, or comments / experiences with them?
 
(***) I measured my mount, and the "knobs" or "axis" (sorry if those are not the right words) are 6mm and not 5mm as I first thought. I wanted 16T pulleys but I'm not finding them in 6mm. Does anyone have an NEQ5 to provide some inputs? Or otherwise general knowledge on pulleys/belts about which considerations should I have before buying?
 
I still need to go through batteries/power options, connectors, case, etc., but I want to start with this for now.
 
Oh and last but definitely not least, I'm traveling to the US on December (Miami / Chicago Loop). Does anyone know a good store where to go and physically buy electronic parts? I'd rather see and touch these things than ordering over the internet (which obviously will do if I can't find a proper store).
 
Thanks a lot to everyone for sharing so much knowledge! I'm totally thrilled by this project :)
 
Cheers,
Sebastian

Howard Dutton
 

On Wed, Nov 6, 2019 at 06:07 AM, <bahrt@...> wrote:
OnStep potential setup:
- Arduino Mega2560 
- MKS-Gen L v1.0 
Just to be clear you need only the MKS Gen-L, it has a Mega2560 MCU on-board.

- Nema 17 motors, 0.9deg, 0.9A (*)
- LV8729 drivers (**)
- Timing belts and pulleys, 2.5:1 - GT2 16T/40T (***)
- HC05 BT + ESP-07 WiFi
 
Only Serial1 AND Serial 2 OR Serial 3 can be activated on Mega2560.  Serial 1 doesn't function as-is on a MKS Gen-L due to board design.  So WiFi or BT not both (unless you get fancy and correct the board circuitry.)  And if WiFi use a WeMos D1 Mini NOT ESP-07.

 
(*) The options I'm considering are Stepper Online vs. Oriental Motor. The Oriental's price is 4x Stepper Online's, which translated to my currency is really a lot of money. The question is: what are the differences that I would notice between both of them?
 
Most use stepper online, I'm aware of no performance difference.

 
(**) This is the item where I spent the most reading-time on. I started with DRV8825, then considered TMC2209, then disregarded both for LV8729 after a Howard's post, then read about TMC2100 and 2130 (with this later one considerations included). I would think that FYSETC TMC2130 v1.1 with SPI enabled is a good choice (like this one from Amazon), but I'd like some inputs on this if possible. Any "magic" recommendations, or comments / experiences with them?
 
Overall TMC2130's are better for this in my opinion.  LV8729's would be my second choice.  For focusers/rotator A4988's are usually fine but TMC2208's are better.