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sloz1664

Automating a 2.1 metre Pulsar Dome. Phase Two- Motorised Shutter

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After automating the dome on my Pulsar Obsy which has been a revelation, I have spent a considerable time researching how I could automate on what is a very basic manual shutter. The existing shutter slides on the aperture side of the dome and supported by two curved aluminium rods at the rear. What I will require is to create a runner system to allow the shutter to open & close smoothly, be aligned & contained to enable attaching a motor and drive system, thus allowing software automation.

The rollers are 30 mm dia nylon roller bearings, four per side of the shutter opening. This will allow the shutter to slide smoothly over the open aperture.

 

1767189558_Midroller.thumb.jpg.21af5586e006bf10a9b47fa1b00a321c.jpg 

The rear side of the dome needed to be built up so I could affix tracks to enable the shutter to slide smoothly to the rear of the dome. This was relatively tricky as I had to build rear track support blocks to line up with the existing shutter. I plumped for wooden supports as I had to mount the on a sloping curved dome and as they had  to be mounted vertically, creating some rather complex compound angles and curves. These were bonded in place and further secured with stainless screws from within the dome. Then having formed the arc in which the shutter will run I attached UPVC strips to complete the assembly. The sides will be cladded with UPVC.

Former.thumb.jpg.8da94048456cb0778e70ea7b3eeccc41.jpg

The calculations had to be quite precise as I didn't have much breathing space :shocked:

Close.thumb.jpg.e409288d835d1efb93335077394ec615.jpg

To be continued...........

Steve

 

 

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Side supports have now been fitted to the rear roll off section of the Dome and does it need a clean :shocked:

IMG_20200727_190628.thumb.jpg.b095512bf3802f273a361c051b7aa61b.jpg

Next is to build the Shutter Motor Assembly:-

1992166864_ShutterMotorassembly.thumb.JPG.44fcc39386fe4d062489ff558196544d.JPG

Unfortunately, installing the motor requires a cut-out in the roof of the Dome. A barrier will need to be built to stop any water ingress.

232823125_Domesection.thumb.JPG.bf9151bfa8dca9a30bffe276dd1fcc36.JPG 

Steve

 

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Cut-out completed on the Dome to allow the insertion of the motor assembly:-

54934900_DomeCutout.thumb.jpg.69a5d359a45595d8247daab68cfdef74.jpg

1026974036_DomeCutout_1.thumb.jpg.eec3b08b68200fc70cebd95c1bfc81ee.jpg

Barrier fitted to stop any water ingress getting inside the Dome:-

Barrier.thumb.jpg.419f32d29d3b384205038e0dc4ae0e5c.jpg

Steve

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Posted (edited)

Motor assembly has been built & installed in position with the Observatory Dome:-

617210992_ShutterMotor.thumb.jpg.8f818e48461038a0cda1200350886680.jpg

Next.....To bond the drive belt to the base strip & initial test.

Steve

Edited by sloz1664
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Thanks Nigella. Just hope it works. If it doesn't, at least I have a nice smooth manual shutter :)

Steve

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Next, drive belt fixed to it's base rail.

1114690735_DriveBelt.thumb.jpg.bcf21db060b3982f03722a554842893e.jpg

Finished the rear runner assembly by fixing a top cover strip on each side to stop the rear of the shutter lifting out.

59042798_ShutterCover.thumb.jpg.2557f9340114e9c33563a933cb39b766.jpg

Steve

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36 minutes ago, sloz1664 said:

What specific information do you need, Nigella?

Steve

Hiya Steve, just the bits you used and where you bought them would be great and I can see if I can do the same. Would be very helpful, thanks.

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