HEQ5 Pro -- how heavy can it go?

I have the same mount and use two counterweights for my 8' ACF, works well. But for DSO imaging I would not go over 10-12 kg with the scope, camera etc. Balancing the scope is a very important thing, always do that before imaging.

Bulky Newtonian are prone to wind ACF with big dew shield too.

Hello,

On my HEQ5 (rowan) : T200/800 UNC + tube rings + camera + corrector = less than 8,5 KG   (finder scope 0,5 Kg is useless and not installed –> astrometry ) /  No tripod –> "fixed column" /  OAG / RMS between min 0,35" and max 0,9" - often between 0,5" & 0.7"   (depending on seeing and polaris distance at 7 meters altitude & dew)/ polar alignment with sharpcap /  PHD2 guiding / OAG requiered  a (very) long adjustment period in order to obtain a "good guiding "  : really "sensitive" for PHD2 algorithm (round stars in corners & edges + guiding camera focus - altair 178M )

Between optical adjustment (OAG & F/D 4…) & Payload limit ,  I wonder where is the "max" payload  of my mount (photo) : under 1" RMS today, even on celestial equator . 

Wind < 15km/h seems to be a limit  (for T200/800)

1,20" = imaging camera (échantillonnage)  so "it's OK", the less RMS is the best it is (long exposure 720" , and more are Ok  : limits are camera's exposure limit , not guiding ). If payload would be > 8,5 Kg , I think that it could be "a little bit more" difficult to get a RMS < 1,20" at celestial equator (but "not elsewhere")  requiered by imaging camera It also depends on tube lenght (cantilevered / porte-à-faux) .  RMS value is a good indicator for testing payload. It could be a good test to build a kind of "weight belt"  placed around the tube center for checking max payload in fact.

Sorry for english, hopping it's understandable  

My not modded Heq5 pro has a  payload of 18 kg.
The Quattro 10"Steel tube is mounted since Summer 2018
I operate the mount with 13.5 Volts.
The walls of my observatory protects against wind up to about 20 km/h.

I briefly had an 8" RC weighing in at about 26lbs. It was a temporary arrangement but I was able to get up to 90s subs with it.

Andy Wray:
I think I'm reaching the limit of my Rowan-modded HEQ5 Pro ... I've got 15Kg of counterweights and about 11Kg of payload.  It seems to be coping, although the DEC axis may be struggling a bit.  I know we are only supposed to go to about 1/2 the rated load, but just wondered if anyone else has taken it this far?

I have a similar setup. A very old black HEQ5 which last night was carrying a SW Quattro 200pds Newt, filter wheel, TEC cooled camera, 60mm guide scope etc. Probably 12KG I think but I have 3 counterweights very nearly at the bottom of the bar (I think the old bar is different)and I was actually taking 2 minute unguided subs. IIRC it will do 2 minute subs @ 2350mm with my C925 as well

I recently spent weeks rebuilding and tuning it though: goto upgraded, Rowan belt mod, Geoptics grease and new bearings. Take your time rebuilding these things and they really can perform beyond their spec. Before I rebuilt it it could barely haul its own weight around but 20 year old grease was defo the problem. I certainly wouldnt say there was anything wrong with the bearings

Does your dec struggle more one way that the other? I found dec can be impossible to balance properly until someone gave me the advice to put the focusser at the top

As addition
Guiding test-shot, exposure time : 20 minutes
Heq5 Pro 
SW Quattro 10"S (focal length : 1000mm)  Guiding Lacerta Mgen2  / 9x50 guidescope(fl : 180mm)
Camera : Moravian G3-11000c
RAW image out of the camera. Not debayered, Not calibrated, not processed in any kind

@Michele Campini It looks like you have some nice upgrades on your mount.  I see improved dec axis knobs, a losmandy mount adapter and new clutch knobs etc.. Would you mind telling me where you got those please?

OK, it's cloudy and cold so I decided to see how my guiding was with the heavy load from my dining room.  No way to really polar align as I only have about twenty degrees of view to the east out of  some old slightly blown double glazing.  I managed to at least drift align the altitude and guessed the azimuth.  Despite all of that, the mount with my Orion SSAG guider managed sub arc-second guiding   Hoping for even better once we get clear skies here in the UK.  If anyone has any tips for me on the guiding based on the plot below, please feel free to critique.