Gina's Observatory Roll-Off-Roof Automation

[Gina]

Not quite so cold today and sunny once the fog had burnt away.  Checked the large chain pulley with the chain link and the groove was indeed too narrow for that so I put pulley on the lathe and turned the groove around a millimetre wider.  The link clears well now.

Edited February 9, 2015 by Gina

[Gina]

Got the large pulley and cover installed and the chain runs over it it nice and smoothly   The cleat for the storm clamp clears by about a millimetre and I think the blocks to hold the chain ends will clear and work alright   Also reinstalled the sliding door support timber and the separating wall cover panel.  So far looking good for the ROR automation

BUT...  The ROR carriage on the south side is catching somewhere else now and stopping the roof closing   ATM I can't see where the trouble is but it stops about half way.  Come indoors for a rest and a think after struggling to try to free the dratted carriage.  I need to get this problem sorted out PDQ before the next lot of rain arrives - hopefully not today.  I also need to get the observatory roof working properly before I can even consider any imaging

Forecast is for a clear night and I was hoping to get the MN190 set up for imaging - been working on the power distribuiton and focussing control to use this scope on it's own.  Also been working on the EQ8 mount power supply to make that work properly.  The solution turned out to be to use a 12v sealed lead acid battery as backup and regulator for my Maplin 13.8v PSU.  I've made up a fuse box to mount on the pier to connect supply to battery and battery to mount.  I'm not leaving a 45AH battery connected to anything without fuses, unattended.  The risk simply isn't worth it.

When I shall eventually get to do another imaging run I really don't know!   It just seems to be one thing after another stopping me.  I'm better in health and up to some outdoor work but the gear is letting me down now!   It always seems to be so near yet so far!!!

Edited February 21, 2015 by Gina

[Gina]

Found the proclem   The wheel frames were catching on the screws holding the track down.  I need to add some spacers to keep the wheels in the centre of the axles.

[Gina]

With an improvement in the weather I am progressing with the outdoor jobs.  I have made a list of jobs to do to get the ROR automation working

1. Spring clean scope room and tidy warm room
2. Sort out south side roof rollers - either with spacers or print new carriers
3. Fit north side wheels and carriers and lay angle (running track)
4. Fit support brackets for fold down flap axle
5. Make new fold down flap
6. Make pulleys for flap cord
7. Fit pulleys for flap cord
8. Make and fit brackets for attaching chain ends to ROR
9. Shorten chain and connect up
10. Make up ROR control electronics
11. Test & debug ROR control electronics

Item 1. is needed to provide a safe environment to work on the following steps   I have made a start by picking up numerous screws, nuts, washers and other bits and bobs.  Have also moved EQ8 packing case that I used in sorting out problems with the mount, back into a corner in the warm room under the bench.  An amazing amount of mud has got in the observatory with all this wet weather in spite of my efforts to clean my boots on the door mat   So that's a job for "Henry the hoover"

Edited March 7, 2015 by Gina

[Gina]

I have now cleared all unnecessary stuff out of the scope room and thoroughly cleaned the floorboards including the expansion gaps in the T&G.  I think I might just leave the floor tiles outside stood up against the north wall of the obsy and let the next lot of rain wash the mud off

[Gina]

Think I might just brush most of the dirt off the floor tiles and put them back.   We haven't seen the last of the rain and hence mud, whatever today might be like, so I think a wash off of the tiles would just be a waste of effort.  Decided I can't leave them outside or they're likely to take off across the fields in the next gale.

[Gina]

The floor tiles are back down in the scope room but one or two don't fit properly - I guess some were out in the sun and warmed up more than the others.  They'll probably fit once they stabilise back to the same temperature.

[Gina]

Been working on the design of the new east wall flap - which also acts as a window.  It consists of a wooden frame on three sides and a 1" OD aluminium tube on the other (bottom).  The tube acts as an axle for the flap/window.  Filling the middle is a twin wall polycarbonate panel, 10mm thick and 2m x 610mm.  This is held in aluminium channel at the ends which both holds the ends and seals them to prevent moisture and muck getting in between the layers.  The top will be screwed to the wooden frame and the bottom clipped to the pipe with 3D printed parts.  The wooden frame is also attached to the tube with 3D printed brackets and the tube runs in printed brackets attached to the two eastern main corner posts of the observatory.

Here are some screenshots of the window modelled in SketchUp - first two in the open position and then in the closed position.  It will close against the main body and ROR, of the observatory, with draught excluder to weatherproof it.  I have excluded everything except the window/flap and the corner posts for clarity.  The polycarbonate channels actually run at right angles to that shown in the model but SketchUp insisted in drawing the translucent effect like that

Open - viewed from above.

Open - viewed from below.

Closed - viewed from outside (east).

Closed - viewed from inside.

Aluminium channel detail.

Clip to hold polycarbonate sheet to aluminium tube between end fastenings.  Mayb one, maybe two or perhaps three depending how flexible the polycarbonate proves to be.  I haven't shown these in the main model.

Edited March 11, 2015 by Gina

[SnakeyJ]

Design looks good Gina - are you intending to 3d print the hinge brackets?    Hope the weather holds and you manage to get this all completed soon and can get back in to the imaging business again.   Having now packed up my obs, I'm feeling quite jealous - but should be back in business with a modest temporary build in the not too distant future, once the settling in and unpacking is finished

[Gina]

Thank you Jake

Yes, In fact I have already printed the "hinge" brackets and now printing the frame brackets that connect the wooden frame to the aluminium tube.

Here's a screenshot of the SketchUp model of the frame brackets.

I now have my MN190 imaging rig working properly and just waiting for some clear night skies   I'm hoping to image M1 in NB Hubble Palette.  Thick fog tonight

I haven't got either of the triple imaging rigs ready yet but it's galaxy season coming up and it may well be autumn before they show their usefulness though there's always M31 to try out the widefield rig on

Edited March 11, 2015 by Gina

[Gina]

Running out of dark green filament   Not to worry I've plenty of other colours   Probably change over to black

Edited March 11, 2015 by Gina

[perfrej]

Jeez! Will you ever be done with this? I guess it is like sailing; it is not the destination but the travel itself

/per

[Gina]

Getting there   Ever so slowly   Weather and other problems have got in the way   Making progress now

[ghostdance]

Gina, you are a marvel...such skills, tenacity and dedication

(Would love to see you presenting a 'DIY Astro' slot on S&N!) 

[Gina]

Thank you very much

[Gina]

Have now printed out all the parts for the east wall flap/window so if the weather is reasonable I may be able to make it up tomorrow   Need to cut the pieces of wood to length and glue them together, drill bolt holes and assemble.  The wood will need treating too.

Edited March 12, 2015 by Gina

[Gina]

Pouring with rain today and the things I want to use are in no less than four different buildings    The grass is under water and mud which I don't really want to tramp into the observatory. 

1. Polycarbonate sheet in observatory.
2. Wood side pieces and all plastic parts indoors.
3. Top wooden piece in garage.
4. Bench saw for cutting the wood in big shed.

[Gina]

Rain has stopped and flood has subsided   Been out and brought the parts indoors.  Also, checked height measurement in the observatory and to provide a decent overlap at the bottom of 2" the flap height wants to be 25".  So a slight change to the model - moved top rail up by 25mm (approx 1").  I have the parts laid out on the table and arms of a chair in the living room.  The plan is to mark the timber for where to cut before taking them out to the mitre saw in the shed.  I expect to do the sawing tomorrow as the light is beginning to go now.

I might attach the top bar to the sides with pieces of wood on the outside.rather than rely on gluing the edges.  The top edge of the polycarbonate could have a moulding to hold it in place and waterproof the edge.  Either a shop bought piece if there's anything suitable or I could use my router to make it.

[Gina]

Photos.

[Gina]

All prepared for for sawing and NO POWER   I have a problem with the mains power in the shed so I'll have to sort that out   Drat!!!

Cold out so I'm back indoors to warm up and have some lunch.

Edited March 14, 2015 by Gina

[Gina]

Found the problem - RATS!!   Extension cable chewed through   I'll repair it but I'm not doing any more out of the house today - it's just tooooooo cold - bitterly cold, in fact

[Gina]

This project will be on hold until the weather improves   Where's spring got to???

[SnakeyJ]

This project will be on hold until the weather improves Where's spring got to???

It was very cold and damp down here last night, made worse with no idea of how the heating works (first night in new house). All sorted now, but took a while to work off the chill this morning!

Springs definitely coming - the buds are breaking on the magnolias and the grass is growing again :-)

[JamesF]

I'm not sure the grass actually stopped growing this winter, it's been that mild.  It certainly has been cold this weekend though, particularly today.

James

[Gina]

Hope you get your new house sorted out soon Jake   This is not a good time to be without heating

The grass has kept growing here James but the goats are keeping it short