202 replies to this topic

[Rustler46]

After a brief discussion with my carpenter friend James, I'm not going to measure elevations of support post footings and cutting posts to proper length.

My method will be to set the on-edge 2X4 track at trial locations at the far end. Then sighting along the lower track rails will determine if the upper positions need to be raised or lowered. This will be much easier than elevation measurements and cutting 4X4 posts. The posts will be cut to proper length based on where the track rails are attached. These rails will be screwed on to the side of the 4X4s rather than on top.

But I'll be laying low for a day or two due to rain and recovering from a cold. But the end is in sight.

Best Regards,
Russ

As can be seen, the open roof track will extend above the top of the north side hedge.

[Rustler46]

The winch hardware arrived today in two separate packages. Hogslat.com is the vendor.



Everything is of top quality at a very reasonable price. It sports a quality worm, worm-gear set. Some offerings by other sources have low quality, quasi worm gears. Shipping for the winch itself was around $21. As I added other items to the cart (cable, drive rod, clamps) shipping stayed the same. That's what I call honest value.

The shepherd's crook drive rod is great value at $7. It is 1/2-inch diameter & 3 feet long, powder coated paint. A nice added feature is there are 3 flats machined onto the drill end so that it fits into a 3/8-inch chuck.

Russ

Edited by Rustler46, 29 April 2024 - 09:25 PM.

[astrohamp]

Battery powered drivers being plentiful these days you should be able to find a reasonably priced one with a 3/8 chuck to dedicate to the task.  Sometimes life can be made a little easier.

[archer1960]

After a brief discussion with my carpenter friend James, I'm not going to measure elevations of support post footings and cutting posts to proper length.

My method will be to set the on-edge 2X4 track at trial locations at the far end. Then sighting along the lower track rails will determine if the upper positions need to be raised or lowered. This will be much easier than elevation measurements and cutting 4X4 posts. The posts will be cut to proper length based on where the track rails are attached. These rails will be screwed on to the side of the 4X4s rather than on top.

But I'll be laying low for a day or two due to rain and recovering from a cold. But the end is in sight.

Best Regards,
Russ

As can be seen, the open roof track will extend above the top of the north side hedge.

Roof Track - 1.jpg

As long as you keep the hedge trimmed!

[wonderinunity]

This is fantastic. A permanent home for a C11.
Walk in. Turn on the drill. The sky opens herself to you.
Get straight to the wonder. Congrats!

[Rustler46]

This is fantastic. A permanent home for a C11.
Walk in. Turn on the drill. The sky opens herself to you.
Get straight to the wonder. Congrats!

Thanks for your comments Archer1960 and Wonderinunity. Yes, I'm looking forward to getting everything running as planned. I've been sick for the last few days, so not much has been done. I did making some measurements so that the open roof track can be properly placed. Then I'll make some drawings for where to place the post brackets in concrete pods. It would be nice to get the concrete curing so that the posts can be erected and tracks attached. Then I can go on planning how best to implement the winch system.

Best Regards,
Russ

Edited by Rustler46, 01 May 2024 - 06:23 PM.

[Rustler46]

After being ill for that last 6 days, Renee & I are starting to feel better. So today I made use of some measurements recently made to put together this rough sketch of the spacing of the holes for the concrete pods. I intend to run a string-line along the east and west walls to assist in locating where to dig the foundation pod holes. I still have enough QuickCrete mix and fill-in stones to finish the foundation. The stones will be used to take up some of volume of the 8-inch diameter X 15-inch deep holes. Each will start with concrete mix on the bottom, followed by stones then more mix. I just need to end up with at least 6 inches of mix on the top. This will ensure the metal post brackets can be placed without running into the stones. Any left over mix will be used to make some more stepping stones for Renee's flower garden.



I need simple drawings like this to make things work out right. Once I get the open-roof tracks in place I can at last begin using my new "simple observatory". The winch operated movement of the roof will come later. For the time being, the PNW rains have settled in for the new few days.

Question:

Does anyone know what would cause all the editing buttons on top of my reply window to be inoperative? What I type in the reply box below is totally without word-wrapping, looking rudimentary with a fixed font. This has happened before. But I don't remember what it took to fix the problem. I'm using a 2021 MacBook-Pro with Apple M1 Pro chip, running Mac OS Sonoma 14.4.1. Any suggestions?

Best Regards,
Russ

Edited by Rustler46, 03 May 2024 - 08:30 PM.

[Rustler46]

The last nine hours here on the Oregon Coast has put the roof to the leak test. During that time period over an inch (2.5 cm) of rain has fallen. The rain gutter appears too be working well despite being of rather minimal cross section. This was necessary so that the gutter would not interfere with the side rails on the track when the roof is slid open. I have secured a short section of 2-inch plastic pipe to the rain gutter outlet to route that water over into the Arbor Vitae hedge on the west side. This greatly reduces splashing from water running off the roof.

As for the roof itself there has appeared one minor leak that shows up on the metal rafter 2 feet in from the west wall. For a while I had assumed this was due to the fact I still haven't secured all the screws on the last Suntop panel. To do so will require me getting up on the roof with some plywood protecting the roofing from my weight. But on further thought, lack of these screws should not really matter since successive panels are sealed by a thick layer of caulking down the 10-foot overlap joint. So what I've discovered is water is running along one of the purlins until it reaches that second rafter and then running down the slope until a convenient exit point. Thankfully this is not at a location where any water sensitive tools are stored. My lawn mover is not being dripped on and the Losmandy G-11 mount is under a TG365 cover in the center of the structure. And that cover is staying dry.

So the best I can tell there is one or more screws holding down the roofing that were not installed perpendicular to the roofing surface. This would prevent the waterproof washer underneath from making full contact with the polycarbonate roofing. Another possibility is that one or more screws were not full tightened down to just make contact with the roofing. Tightening down too far would have a similar effect. In any case when I get an opportunity, I'll have a look at the screw situation over the water entry location to see what needs to be done.

Overall I'm pleased at how well water is being shed, especially since I did not maintain the minimum rise recommended by the roofing manufacturer. It had recommended a minimum of 1-1/2 inch per foot. To prevent excessive height on the north end I went with just 1-inch per foot. Even at that reduced rise, the roof is considerably steeper than the original observatory 40 years ago. See the photos on the original post of this thread.

I'm also pleased at how the inside floor is staying mostly dry despite the large ventilation openings at the bottom of the walls. The one foot roof overhang on all sides reduces rainfall impacting next to the walls. Surface water soaks right into the landscaping cloth into the sandy soil. I have noticed when there is a strong wind during rainy weather some rain blows in, particularly on the more open north end. If this becomes a problem, that opening can be reduced from its present height of 8 inches.

Clear Skies!
Russ

Edited by Rustler46, 04 May 2024 - 12:32 AM.

[astrohamp]

I keep forgetting to use grid paper for my concept sketches.  I've also had to start putting hardware cloth at some shed to ground gaps to try and keep out some of the locals.  Chippies, squirrel, skunk, coon..., ugly yes the wire grid is but the burrowing and leftovers are more then a nascence. 

 

Is good to read you both are on the mend as 6 days can run down the engine quite a bit.

[Rustler46]

Yesterday I was able to establish the last two concrete foundation pads for the open-roof supports. Digging the 8-inch diameter by 15 inch deep holes was challenging because of many roots from the nearby hedge. The metal post brackets are set at the design spacing. I'm still not up to full energy levels after being sick. Now the concrete will need to be fully cured before I can set the 4X4 supports and track rails. The end is in sight.

CS,
Russ

[Andrea Salati]

Russ,

 

Thank you for posting your periodic updates. I love following the process and dream of being able, one day, to do something similar.

[desert_sage]

Russ,

 

Sounds like a nice roof, one minor leak shouldn't be hard to fix!

 

I bet you are looking forward to "first slide" soon!!

 

It has been a nice week here, but unfortunately I've been stuck doing brush abatement so that the fire department doesn't get too excited, so no progress on my front.

Edited by desert_sage, 09 May 2024 - 10:47 PM.

[Rustler46]

Conditions have improved so that some progress was made today in getting the open roof track installed. Renee and I are feeling better as we recover from our sickness, and are regaining some of our strength and endurance. We had a few hours this afternoon to work together in getting the support posts set with temporary bracing to hold them in place. For now I just used some 1X4 X 10-foot wood as diagonal bracing. These will be removed as the 2X4 tracks and permanent cross bracing is attached.

I did work on how the tracks will be attached to the building's corner posts on the north end. At the far upper ends of the tracks, these will just be screwed onto the sides of the 4X4 support posts. So tomorrow it should be possible to get the open roof tracks in place and all braced. The first roof slide-off will follow as soon as possible.

Here are some photos of the progress.


The open-roof support posts are seen on the right next to the hedge. Renee's mushroom growing bed is seen in the background. We are harvesting some asparagus and wine-cap mushrooms from that area.


This shows how the tracks will be attached to the observatory building north side. The tracks will be supported by the short 2X4 seen just above the yellow siding. The track will be in contact with the lower side of the metal roof rafter, which will slide on the track.

More to come.

Best Regards,
Russ

Edited by Rustler46, 13 May 2024 - 10:09 PM.

[Rustler46]

Today I was able to get both open roof rails installed. It takes more time than might seem necessary. The hedge needed to be lowered to allow for passage of the roof as it is slid open.

I could have slid the roof open at the end of the day, but decided to wait until tomorrow when the side guards on the rails are installed. These will prevent the roof from straying to the side as it is opened. I just ran out of time and energy to finish that task. Also the final 2X4 diagonal brace needs to be secured to the rail support structure. At that time I'll make the final adjustment to getting the support posts accurately vertical. They are close but could use a bit of tweaking.

Here are some more photos of the project.


View from northwest corner toward the north


Looking along the east wall


This is the view from east side. There is no need for diagonal bracing under the rails because they are securely attached to the corner posts of the observatory building. And those posts are solidly in place, and will prevent any movement of the rails longitudinally. There will be 2X4 diagonal bracing between the support posts to hold them in position.


Looking east


This shows the stainless steel sheet metal I placed under and around the end of the roof rail. This will reduce the amount of rain water than might run down the rail and divert it off outside the siding.

That's where the project is for now. I'm hoping the weather stays clear for tomorrow night first light.

CS,
Russ

Edited by Rustler46, 14 May 2024 - 10:46 PM.

[Rustler46]

Today was the first open roof event. After attaching side rails on the open roof support rails, the roof slid open without undue strain on my old body. I do plan on installing the winch powered open roof solution. But for now the manual method will suffice.

Here are some photos.


It was a bit windy today. So I opted for caution by holding the roof rafters down with some nylon straps attached to the open roof rails. The Losmandy G-11 mount can be seen inside ready for whatever telescope is installed.

Edit:
I still haven't come up with a simple, but secure method to connect the roof to its support track in the closed or open position. The original observatory from 1985 just used trunk-latch hardware attached to the wood rafters and top frame of the walls. But the use of hollow metal rafters (light & strong) makes that method less secure. It would rely on sheet metal screws holding in thin metal against the lifting force of sometimes ferocious winds. So for now all I have is nylon straps cinched around metal rafter and wooden rail. It works but seems less than ideal.


Here the Celestron-11 is shown ready for the night sky sans dew shield. In the balanced operating position, the roof will not clear the telescope. So when roof is closed, the telescope must be positioned out of the way.


This position of telescope in dovetail saddle clears the roof at it is slid closed.


Here's another view of the telescope after the roof was closed. I'm not sure it is a good idea to have that unbalanced load being applied to the Losmandy dovetail plate at bottom of the C-11 OTA. I may opt for a different home position for the telescope/mount that will clear the roof. Counterweight down and OTA pointed east may clear the roof. Also counterweight horizontal with OTA pointed south might work. So I'll need to experiment with that.

But at this point the new "simple" Ocean Observatory is open for business.

Best Regards,
Russ

Edited by Rustler46, 16 May 2024 - 12:54 AM.

[Rustler46]

Today I added some more permanent diagonal bracing on the open-roof supports. For this I used 1X4 by 10-foot treated lumber. A block of treated 4X4 tied the two braces together where they crossed.

[astrohamp]

I was going to suggest adding a couple of 'head banger' diagonal braces to the out posts reducing 'roof out' rack.

Then I went back in your image posts to see the slide girders are full length.  Nice.

[Rustler46]

Open Roof C-11 Stowed - 2.jpg
Here's another view of the telescope after the roof was closed. I'm not sure it is a good idea to have that unbalanced load being applied to the Losmandy dovetail plate at bottom of the C-11 OTA. I may opt for a different home position for the telescope/mount that will clear the roof. Counterweight down and OTA pointed east may clear the roof. Also counterweight horizontal with OTA pointed south might work. So I'll need to experiment with that.

But at this point the new "simple" Ocean Observatory is open for business.

Tonight looks to be clear for a first-light with the C-11 in its new enclosure. In addition to what can be seen up in the night sky I hope to see if there are other closed roof home positions for the G-11 mount that will clear the roof.

Edit:
This position clears the roof and should work for the Losmandy G-11 home position.



This will be much better than having to slide that heavy OTA up and down the dovetail saddle to clear the roof. Clear skies are holding tonight near sunset. I'll just have a look at the Moon and maybe some double stars. It has been a long time since I've used my trusty Celestron-11. Now it has been set up on its mount permanently. Hallelujah!

Another edit:
I had a short but enjoyable session observing the gibbous Moon with a number of craters prominently displayed: Plato, Copernicus, Bullialdus, Clavius and Tycho. The Sky and Telescope mirror-image Moon map was a great help in this regard. What a joy not to have to tear it all apart at the end of observing. It will be even more enjoyable when I get the powered winch on line for opening and closing the roof. But that will be a bit later, as I have some other work items of greater importance on the property. Some hedge pruning is on the list along with some other things related to the vegetable garden. These have been put on hold for long enough while I was getting the observatory to this stage.

Best Regards to All,
Russ

Edited by Rustler46, 17 May 2024 - 11:56 PM.

[Rustler46]

Renee & I took a break from gardening work. So I had opportunity to see how to mount the roof opening/closing winch. I removed the worm-wheel & split reel assembly to reduce the weight. Just the metal frame & worm-gear remained. I used some clamps to hold the frame in place to see how it could be arranged to work. Here are some photos.


First the drive loop & worm-gear needed to be offset far enough to clear the wall when using the "shepherd's crook" drive rod. This meant the frame needed to overhang the side of the wall by 3-1/2 inches. I have some pieces of L-channel steel that can be used to secure the winch to the observatory structure.


This is the general configuration for a brace to hold up the frame as it extends behind the top 2X4.


Another piece of L angle steel will bolt to the side of the winch frame and the under side of the top 2X4.


This shows it from the other side. The top 2X4 is not level, but is tilted at the same angle as the roof's pitch. This causes the drive loop to be angled back in toward the side wall. That's why 3-1/2 inches of overhang is need for the drive loop to clear the wall.


To the right of the diagonal brace is where a short 2X4 reinforcement will connect the upper 2X4 to the mid wall 2X4 below. I inserted a short piece of wood to show where that will go.

Edit:
I forgot to mention that there will be one bolt through the upper 2X4 and existing hole in the winch frame that will hold it. Along with the brace and 1 or 2 bolts attached to the side and the L-channel metal should be enough to hold the winch firmly in place.

That's where things stand for now.

Clear Skies,
Russ

Edited by Rustler46, 20 May 2024 - 03:16 PM.

[Rustler46]

Today I applied some Carnauba wax to the roof support rails. I had this automobile polish wax on hand, and decided to give it a try. As expected the roof slides much easier. This takes away a bit of the impetus to move ahead quickly on the winch. This will still be done, but not right away.

I have noted one thing needing correction. That is the west side open roof support rail is in need of being raised bit to a steeper slope. At present it doesn't quite match the slope of the west side of the observatory. So the far north end of that rail needs to be raised a bit. That will make things slide even more smoothly.

Tonight I plan on using the Celestron-11 telescope on a near full-moon night. I want to re-establish the go-to pointing model by aligning on a half dozen or so bright stars. Then when done observing I'll slew the telescope to the counterweight down, OTA pointing east position. This will then be selected in the Gemini-1 software as the new home position. This will enable quick telescope positioning that will clear the roof when slid closed.

Clear Skies,
Russ

[Rustler46]

I have noted one thing needing correction. That is the west side open roof support rail is in need of being raised bit to a steeper slope. At present it doesn't quite match the slope of the west side of the observatory. So the far north end of that rail needs to be raised a bit. That will make things slide even more smoothly.

Tonight I plan on using the Celestron-11 telescope on a near full-moon night. I want to re-establish the go-to pointing model by aligning on a half dozen or so bright stars. Then when done observing I'll slew the telescope to the counterweight down, OTA pointing east position. This will then be selected in the Gemini-1 software as the new home position. This will enable quick telescope positioning that will clear the roof when slid closed.

Today I raised the west side open-roof rail by about 1/3 inch on the far north end. This made the slope of both segments of that side line up much better. Also I'll work on some of the steps needed to mount the winch. Progress is slowly being made.

 

Also Monday night I did have a nice enjoyable session viewing the Moon and 4 Spring globular clusters. These showed well despite the near full Moon bright sky.

 

Clear Skies,

Russ

 

[Rustler46]

Here's what was accomplished in mounting the winch.

 

At present the winch is held under the upper 2X4 by a 3/8 inch bolt.

 

This view from the north shows how one of the reels is lined up under the roof's center metal rafter. Somewhere along that rafter will be the point where the winch cable will be pulling the roof open or closed.

 

Since the winch extends over part of the north wall vertical 2X4, I chose to use a 4X4 to connect the upper wall to the top 2X4. This point will be subject to the winch pulling forces. So any extra reinforcement will be useful. I still need to add some more strengthening by use of L-chanel steel. This will resist twisting of the winch around its 3/8 inch upper attachment bolt. Also a diagonal L-channel will prevent twisting of the upper 2X4 under load. See reply #144 for some views of this.

 

At this time I haven't yet permanently attached the 4X4, since I need to be able to pull the shaft holding the split reels so that the cable ends can be secured to each of the reels.  When the cable length is just right, then the split reel will be secured to the winch frame by its shaft. Then the 4X4 will be attached permanently.

 

Best Regards,

Russ

Edited by Rustler46, 22 May 2024 - 10:02 PM.

[Rustler46]

The winch is now fully mounted and braced.

 

There is a metal L-channel bracket bolted onto the left side of the winch and also to the underside of the upper 2X4.

 

The brace on the right side of the winch really makes the whole assembly solid. Now I'm ready to attach the pulley at the far upper end of the open-roof supports.

 

The way it will work is when the winch is driven, cable will wind up on one of the reels while unwinding from the other. This happens because the cables are wound the opposite way on each reel. On one reel the cables comes off from the top. And on the other it comes off of the bottom. The pulley at the far end is what routes the cable as it moves back and forth. A short pull cable will be attached on one end to a roof purlin and on the other end clamped to the long cable. So as the long cable yo-yos back and forth, so does the roof. At least that is the plan.

 

Best Regards,

Russ

Edited by Rustler46, 24 May 2024 - 01:06 AM.

[Rustler46]

Yesterday I was able to mostly finish the attachment for the far end pulley for opening and closing the roof. The 3-inch pulley is seen at top right in this photo.

 

The cable is seen going around the pulley during the process of attaching the cable ends to the split reel winch. The little block with the sloping top (below the cable) is fashioned to lift the center metal rafter up so it clears the support 2X4 under the pulley and its support 2X4. Since the center rafter sags a bit when not supported, it will run into the far end support 2X4. Thus the sloping block provides a bit of lift so that the rafter slides up on the far support 2X4.

 

Here is shown how one of the winch reels has some cable wound on it.

 

Reasoning on how the whole arrangement is supposed to work I had the realization that the diameters of the cable bundle on each reel will vary, depending on how much cable is on each reel. It is a yo-yo process with cable unwinding from one and winding on the other reel. So for any given worm rotation speed, the winding and unwinding rate depends on each cable reel's diameter at the time. Thus there will be times when the cable as it pulls the roof open/closed will have some slack in the other segment of the loop. 

 

What I intend to do to minimize this effect is to have both reels about 1/2 full to start with. This makes the diameters the same and equal wind/unwind rates. Of course these rates will change. But I want that as the starting point. So the plan is to fill one reel with cable, run the free end around the pulley back to the empty reel. That end will be secured to the empty reel. Then the winch will unwind cable from the full reel onto the empty reel until the two reels have the same amount of cable.

 

I'll report back how all this works.

 

Russ

Edited by Rustler46, 25 May 2024 - 11:00 PM.

[Rustler46]

Well my design it on the go method has failed in one respect. The worm-gear, dual reel winch will not work as I had envisioned. The flaw in my thinking was the failure to see the consequences of unequal rates of winding and unwinding. The diameter of each of the cable cylinders is constantly changing as cable is wound or unwound from the reels. This will cause the cable looping through the pulley to have slack or be overtightened during various parts of the open/close cycle. I haven't tested how this will actually happen under use. But I can seen where problems could arise.

 

So I've reverted back to a simpler design. That is just using a rope attached to the top end of the roof, looped around the far end pulley and back over the observatory north wall. I used some cheap plastic rope to test how it would work. I did apply a layer of paraffin wax to the roof support rails and side rails. It didn't take much of a pull on the rope to get the roof starting to slide up the ramp. With the location that I've situated the pulley, the roof can slide all the way open without running into the pulley. A similar rope on the low end of the roof easily pulls the roof to its closed position.

 

So once I replace the rope with a better type, I going to be happy with this method of sliding the roof open or closed. Here's what it looks like now.

 

The blue rope can be seen going to/from the far pulley.

 

I did have an enjoyable hour or so observing the other night. Along with some globular clusters and planetary nebulae, the highlight of the night was Comet C/2023 A3 Tcushinshan-ATLAS. This was reported on in detail on Celestron-11 in New Observatory (see reply #5). 

 

Best Regards,

Russ

Edited by Rustler46, 29 May 2024 - 01:03 AM.