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Ideas for a pier/mount enclosure that's not an obs


RugbyRene
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Hi all,

 

I'm looking for ideas for a weatherproof enclosure for a pier/mount combo that is not an observatory.  The pier will be 1.2m tall with a SW AZEQ6 mount on top. The scope will be kept inside.  Space is limited so the foot-print cannot be much larger than the scope footing (200-300mm). It would need to be weatherproof and easily opened and closed (manual is fine). The reason I'm looking for an enclosure rather than an obs is down to the availability (or lack of) room to build a full obs.  

So, I'm wondering if anyone has built a similar type of enclosure or has any ideas that could help me.

 

Cheers in advance


Rene

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A few of us start off with a simple builders bucket over the mount then a TGV365 over that, it works very well. Here is a link to a similar recent thread that may be worth a read..... 

 

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I use a TeleGizmo cover and it seems to work very well keeping the mount dry/cool. I gave up with the draw cord and just use an elasticated tie from Halfords - works a treat.

IMG_4405.thumb.JPG.fb6613922ba9a309f611d7798deee4f3.JPG

Lurking under the cover is a SW AZ-EQ6 which takes a RedCat which is stored indoors.

One day I might like something a little more all-enclosing but for the moment it works just fine.

Adrian

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What the others have said.

My HEQ5PRO lives under an upturned plastic dustbin covered by a Telegizmo 365 cover.

 I too have dispensed with the elastic cord and use a webbing belt with push buckle to secure it 

 

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Another vote for TG365 cover… My SCT has lived outside for 2year+ with no ill effects. 
 

I wipe the OTA down at the end of a session if it’s dew covered and give it an occasional airing on bright winter days and a squirt of WD40 on the connectors a couple of times per year…

The only bit that comes inside is the Autostar hand controller- that doesn’t seem to like starting up if it’s suffered days of cold…so I always keep it in the house so it starts up warm.

Edited by catburglar
Corrected typo
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  • 2 weeks later...

Hi

I use garden furniture covers like this

https://www.amazon.co.uk/Woodside-Outdoor-Garden-Furniture-3-25ft/dp/B00CQ4DOK6/ref=sr_1_15?crid=B6JGHHNNA21O&keywords=woodside+garden+furniture+covers+waterproof&qid=1668347114&sprefix=woodside+garden+covers+waterproof%2Caps%2C115&sr=8-15

They come in small, medium, and large sizes.  They are basically open ended cylinders that will drape nicely over an up pointing scope. You can use gorilla tape to stick extra sections on if you need an intermediate size.

I use three of them one inside the other.  Outer will degrade in 12-18mths due to sunlight, but inner two will last.  I found the three layers is 100% weatherproof. You should consider a small heater under the covers to drive off condensation and a remote greenhouse temp and humidity sensor to keep track of dew point .  A 100W bulb will do, or a 12V supply driving resistors.

My scope stays fully mounted with cam and electronics on an exposed rooftop, and it has been there for 5 years.  See attached pic1658192097_2001_mountviews_HiQ_500.thumb.jpg.3b1a0172fc592b497f593f725d713911.jpg

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19 hours ago, windjammer said:

My scope stays fully mounted with cam and electronics on an exposed rooftop, and it has been there for 5 years.  See attached pic

That picture raises a few questions in my mind windjammer; the first being is that I have no idea what half the stuff you have there is, which goes to highlight just how varied this hobby is and how much of a beginner I am at it. A further question I have is that I drop stuff everywhere, just how much has fallen off your roof? Amazing setup 👌

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Hi

Since you ask....and here is probably more than you wanted to know !

Attached is a pic of latest incarnation.  Its called Kevin.  It lives on a small flat roof about 1m wide, facing south.  An umbilical runs from the roof to an office just below for power and remote operation.  You can put two plastic curtains up (made from those cut up garden funiture covers I mentioned) to make a hide and block out neighbours' lights.  One of them is shown erected running from chimney to stink pipe, the other rolled up waiting to be unfurled for deployment(!).

Its a home made GEM carrying a 150mm F5 refractor (in white) and a 90mm F10 guidescope (in blue). There are three finders of progressively narrower fields of view carrying USB cams. The shafts are scoffolding pipe (steel 48.4mm by 4 mm wall) riding in 50mm pillow block bearings.  The counterweights you see in the pic are around 18kg.  

Each axis is identical, just DEC plate bolted to the end of the RA shaft.  The gearing is straight cut spur gears, 4:1 on the final ratio, with a pick off gear on the opposite side for the angle sensor.  The gear train can be uncoupled from the final gears by loosening the chuck, so each axis can be swung by hand if needed.  Each axis has a floating brake clamp on the shaft riding on leather linings and tightened to just hold the scope in its most unbalanced position.  

There are stops either side of the brake on the RA axis that prevent any slop between gear teeth while tracking.  On the DEC axis the brake stops are spring loaded, so that as the drive motor reverses into the backlash void, the springs push back to move the scope.  You get movement of a couple of fields of view in DEC before the springs run out. So on PHD guiding, you get a perfect star cross pattern.

Driving the final gears is a 1300:1 gearbox made up of the epicyclic gears from cheap or broken cordless drills off ebay, mounted inside a short bit of scaffold tube.  There are 4 chambers, each giving about 6:1 ratio.  Cordless drills usually have 2 chambers, are very robust, if crude, and you have to try quite hard to damage the gearboxes.  

Each axis has two motors, a DC slew motor and a stepper, salvaged from my dead printer collection. I could not drive a stepper fast enough for slewing, so two motors.  A little model aircraft standard servo moves an idler gear to engage the slew motor or the stepper to the gear train. The steppers are 7.5o bipolar, giving 4*1300*48*16 = 4million steps/rev for tracking at full microstep setting.  I used the StepStik stepper driver chips for the stepper controllers.  PHD RA+ and RA- commands are used to give pulses of lower and higher speeds for tracking.  There is also an automatic PEC motor speed controller that monitors the ST4 RA signal lines and adjusts the base stepper speed up or down by increments so that PHD RA+ and RA- commands become equally balanced - the PHD dartboard display pattern is nicely circular.

A whole bunch of electronics boxes hang off the pier, RA and DEC stepper and DC drives, motorised focussers for G/S and main OTA etc.  The 100W heater is mounted in the wedge space.  Also an 8 channel video switch - cheap analogue cams are great if you want to monitor what is happening remotely: so there are cams on the bahtinov mask, filter wheel, anti-vibration shutter, pier collision monitor. A spare video channel is used to relay the downstairs computer monitor to a roof top display.  All the electronics can be controlled at the pier or from down below, depending on where you are at - normally remote.

The image train has an anti-vibration shutter, basically a filter wheel that moves a black filter back and forth, depending on the activity on the ST4 DEC and RA signal lines.  When PHD guiding gets too active, the shutter closes until the mount quietens down again, when it opens.  I live near a main railway line and busy road so anti vibration measures are needed for exposures past 300 seconds.

After that is a barlow, motorised filter wheel and Atik 460EX cam. Guide scope rings attach the cam via a strut to a clamp on the OTA finder shoe slot - you can adjust the whole train for collimation and filter flare using the flat lamp and aiming for a centred and circular vignetting shadow.  

There is also an off-axis guider in the imaging train - this takes long exposures in the 5-10 second range, and inputs to a second instance of PHD guiding.  The ST4 commands from the OAG are used to move the guidescope cam on an XY stage tiny amounts in the guide FoV.  These adjustments of the XY stage enable flexing of the image and guidescope to be guided out: the guidescope is fooled into thinking it is off target and moves in such as way as to come back on target and compensate for the flex.

The guidescope is normal except for the coarse and fine XY stages.  The coarse XY stage is used to align with the main OTA, or search for a guide star, and the fine XY stage adjusts for flex.  The guidescope cam inputs into the first instance of PHD running and controls the RA and DEC stepper drives.  The mount performs best (sub arcsec rms guiding) with a guide update at 100ms interval, and g/scope exposures of 10ms to 50ms, so guide stars have to quite bright - mag 7 or so.  You never have this outcome with a fixed OAG in the image train, so this is why there is two stage guiding.

It stays outdoors under covers so setup time and tear down is quick - around an hour, depending on the gremlin population.  

The whole thing is a bit off-piste I know, but happy to answer questions. If only I could fix the image processing malarkey!

Simon

20220911_133619.jpg

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I was also going to suggest the rolling sentry box ^^ as an option. It doesn't need to be any higher than the top of the scope but mine was built to cover a large instrument. I made mine by welding up a steel chassis but the easy way is to source a sentry-box like shed from a garden store and mount it on a rolling wooden board. This board just needs a slot cut in it to let it roll half way round the pier. You can also have some extensions protruding from the pier just above the height of the 'floor board' to stop the shed from lifting. I went for rails rather than free-running wheels.

Whatever you do, be sure you have bomb-proof anti-lift built in. If it can fly, it will fly.

Olly

Edited by ollypenrice
typo
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19 hours ago, windjammer said:

Since you ask....and here is probably more than you wanted to know !

I don't want to steal this post with more comments but I just want to say this is mind-blowing and it deserves a separated post in the forum. I need to read it again... more carefully :)

Regarding the original question (because I'm also facing similar issues), I'm exploring something such as the Motel o'Scope enclosure: https://www.pierplates.com/motel.html

Despite this is a fancy enclosure, there are similar but cheaper options:

There is also the so called 'box observatory' approach: https://stargazerslounge.com/topic/248181-the-box-observatory

However, I'm particularly interested in something such as this one (more kind of micro-full-observatory, check pictures in the last page) but I'm no ready yet for a DIY project like this: https://www.astroforum.nl/threads/eindelijk-weer-een-sterrenwacht-bouwen.1470438/

 

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The rolling sentry box (good description) is interesting.  I like the idea of it leaving the scope area totally free and accessible. 

Rather than rolling away (my space too constrained for that), I wonder if a stackable design would be possible - somehow build up and clip wall sections together and put a roof on top, maybe just a flexible top cover strapped to the walls.  From the man handling point of view, maximum height would probably only be to shoulder height or so.  If that were a 10 minute job I could go for it.

I take the point of wind loading and possibility of fly away v. seriously.  It could mangle the scope on the way out - does not bear thinking about!

(... and thanks all for the kind words about my diy GEM)

Simon

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5 hours ago, tooth_dr said:

Guys what height is best for a pier, mix of imaging and visual, with eq5 sized mount. 

Depends on the length of your OTA. If you want to observe at the zenith, the EP needs to be at an accessible height above the ground and not ridiculously low. It the instrument is rear-end heavy it will sit further forward in the saddle plate and not be as low. If the EP becomes too high it's less of an issue because you can rotate the diagonal to have it coming out horizontally.

Olly

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