New Newtonian Telescope From China Generic equipment discussions · Stephen Shen · ... · 29 · 1894 · 12

The issues with the diffraction spikes look like PA error or rotational slippage in the tube rings to me

MaksPower:
Sure the quality of the machining of the parts is evident, but you haven't used Finite Element Analysis (FEA) to work out where you needed strength, and where you didn't. It's quite obvious just looking at it.

If FEA had been used I would expect you would find your truss serves no mechanical purpose and could have been omitted, making it lighter, many fewer parts, lower cost, and quicker to assemble.

The difference is this:

When you're building a one-off for yourself you don't really care much about the material cost, or your time. Once you have something that works well, you stop. I've "been there done that" many times in my telescope-making days.

But if you are aspiring to build a product that will go into volume production, this is where the product has to be optimized - fewer parts, less weight, less labour, and lower input cost. If this is done well it's quite usual for the result to be better quality, lighter and lower cost than the first prototype you started with. This is what I run in my day job in a large engineering enterprise.

If it is done poorly (Meade and Synta being examples) the product will forever be compromised.

PS like the mirror cell, except that I would not use springs - I always opt for push-pull screws (two smaller M4 screws pushing either side of an M5 bolt pulling). That way collimation stays put, forever.

Hi there,

Thank you for engaging with such depth on the design. Your feedback suggests we should clarify a fundamental structural distinction: This instrument is engineered as a true truss-tube Newtonian reflector. The central component you observed is a "detachable light baffle" – not a load-bearing element. Your perspective actually helped me recognize why the truss might appear redundant: it seems you interpreted it through the lens of a traditional solid-tube Newtonian (referring to conventional one-piece tubed designs, regardless of end openings). In reality, our approach implements a rigid exoskeleton truss framework that serves as the primary stress-bearing structure.

This model represents the compact tier in our truss series, which spans eight configurations:

• 8-inch f/4 & f/5

• 10-inch f/4 & f/5

• 12-inch f/4 & f/5

• 14-inch f/3

• 16-inch f/4

The design rationale is grounded in extreme-field conditions. China’s Northwestern Plateau – a hub for astrophotography expeditions – demands portable yet robust instruments. I regularly transport this telescope in my Jeep Wrangler for spontaneous journeys across this region. Its 3-million-km² wilderness hosts pristine Bortle Class 1 skies, but presents a critical challenge: persistent gusty conditions (Beaufort Scale 4 wind gusts). As Newtonian users know, excessive wind-induced oscillation from the large-diameter tube profile is a key flaw that compromises guiding accuracy on equatorial mounts. Our solution: by decoupling the non-structural baffle from the exoskeleton truss, we maintain optical stability under typical plateau wind conditions – ensuring consistent imaging performance.

On Synta’s limitations (particularly ≥10” models): we’ve addressed the focal plane shift plaguing thin-walled continuous tubes through improved structural design.

Regarding the mirror cell: the shared image omitted our elastically adjustable full-contact mirror locking system – a fundamentally new development diverging completely from existing market solutions. This architecture maintains collimation integrity across -20°C to 40°C thermal cycles while ensuring uniform mirror support.

Thanks again for the thoughtful dialogue – always great to exchange insights with fellow enthusiasts!

If you are considering production, you can source CF tubes specifically for OTAs from http://www.klaushelmi.de/en/
In particular it can have a flat molded-in to accommodate a focuser base, and the tube can include a layer of thermal insulation.

Make this a 25cm f/5 or  30cm f/5 or even f/6 with a robust rack & pinion focuser and I'd be interested. Not interested in f/4.