February 1-14, 2000

February    1, 2000 - Rails and Nails and Walls (cont'd.):     We continued work on the rail assembly and the roof walls.    First, we assembled the West wall of the roof, the lower (in height) of the two sides that will carry the wheels; the two walls differ in height by three inches to provide a slanted rood for rain run-off.     Ben did his usual careful, thorough job, and the wall turned out solid, square, and flat.    Spacer studs were also added for the louvers.    Having learned from assembling the East wall, Ben changed the order of parts assembly and construction for the West roof wall, and construction went much faster.

For the balance of the day, we attached the end rail-support posts to the 1.5"-square cross-support metal bar with bolts;   leveled and squared-up the rails;   and, finally, drilled and bolted the rails to the top sill plates with bolts, washers, and lock-washers.    We also carefully checked the parallelism of the rails throughout their whole length and removed a couple of non-trivial transverse bows that would have caused the wheels to bind.    Two wire cross-cables, connecting the rail end posts with turnbuckles, for added rigidity, were also added.    I would like to congratulate Ben on a remarkably careful, thoughtful, and craftsmanlike job throughout this project.     At then end of the day, I think we were both very satisfied at how well the work turned out.

Architect Ted's advice and assistance has been invaluable throughout this process, as he brings to bear his considerable design authority and practical experience in construction supervision in helping this process go smoothly.

February    2, 2000 - Rails and Nails and Travails:     We checked to make sure the rail end posts and transverse support bar hadn't shifted during the night, and that the rails remained flat, parallel, and true. We decided to see how the East and West walls - sans wheels - would mesh with the rails.    We hoisted up the East wall first, using the brute force of two of us to clear the rails.    The fit was very good along that length of the rail on the shed's sill plate. There were minor low points, at which Ben felt it was prudent to attach the wheels.

We repeated this procedure with the West wall, and the fit was oddly off - it was as if the South end of the wall was higher by about 3/32".     This was the second occurrence of what I call the "A=B, B=C, AšC" problem: We had meticulously checked all the stud lengths and frame members to make sure everything was square, flat, and plumb, as we went along.    We rechecked them in the light of the South end of the wall being higher, and everything was ok;   the rail was still flat and true as well.    So, the difference in height between the North end and the South end remains a puzzle, but not one that we will loose sleep over.

The other "A=B, B=C, AšC" problem arose while attaching the West rail to the transverse support rod and leveling it: The transverse support rod was attached to the East vertical post, and the East rail was attached to the transverse rod.   Both rails were carefully leveled, the vertical support posts for the transverse support rod were carefully plumbed, and the transverse support rod connecting the two vertical posts was also carefully leveled.    So, the West rail should meet the transverse rod, right?    It didn't, and we spent the better part of an hour re-measuring, re-plumbing, re-checking everything twice.    The result of which was that we could find no reason why the West rail didn't meet the transverse rod.    The gap was about 3/8", too large to ignore.   But as we could find no convincing reason for the gap, and as the rails must be as level as possible, we moved the transverse rod up to close the gap.     The transverse rod still looks level, despite what the bubble level says.    If the bubble level itself is the culprit, the whole building should be out of whack - but it isn't.

Ignoring the height difference, we attached the four, soft rubber wheels to the bottom of the East and West walls, and turned next to building the short North and South roof walls.     These posed a tricky bit of construction, in that the top edge of each is slanted, to provide for rain runoff from the actual roof.    And here we floundered on the rocks of trying to accomplish too much and working entirely too long for one day...

The North roof wall went very slowly, as none of us had really thought out the construction process for it in advance very thoroughly.    Finally, it was nearly done when Ted noticed that one end had been measured and cut in error.     To correct it involved ripping out four vertical studs, which had been glued and screwed to the plywood face, as well as the four studs that make up the frame for the plywood sheathing.    The plywood sheathing had to be re-cut and re-measured using a fresh piece of plywood, leaving us now one piece short for the project.    This took a great deal of time to re-do, and tempers were frayed by the end of a very long day.    We decided to take tomorrow off.

February    4, 2000 - Back to the Wall:    We finished up correcting the North roof wall - the one we screwed up on the 2nd - and started in on the South wall.    This proved doubly tricky because it has a cut-out in it so that the roof will clear the telescope as it rolls off to the North.     There is a hinged "flap door" which fills the cut-out and which can be lowered so that the far South sky can be seen from the telescope;   the South is the only part of the sky where the observatory obscures a significant part of the sky, and the flap-door provides unobstructed access to it.    By the end of the day, which was a short day, we had finished assembling all four walls of the roll-off roof.    We are looking forward to getting the roof walls up on the building, bolted together, and rolling down the rails!    The metal siding for the building is also due to arrive Monday (February 7) in the morning.

February    5, 2000 - Dreams....:     A couple of days off.    Remaining work now includes final assembly of the roof onto the building; measuring the assembled roof walls and obtaining flat sheet metal which will sheath the outside roof walls; applying corrugated metal siding to the building; digging the electrical trench and bringing voltage from the house to the building; painting the exterior of the building; installing carpeting, a desk, storage unit, paneling, and miscellaneous other furniture in the building; and, finally, installing the telescope.    I am already thinking about the next telescope for the building, and I am dreaming of a 24-inch Cassegrain with an f/2 primary....

February    7, 2000 - "Up, Up, Up, She Rises!":     The corrugated metal for the sides of the building and top of the roof (the "roof roof", so to speak) arrived after lunch, by which time we had bolted together the four sides of the roof on the ground, and had cut out the holes in the East and West roof walls for the ventilation louvers.     We discovered a blunder made on Friday: another mistake in the North roof wall.    This time, we applied the plywood sheathing to the inner rather than the outer face; not a big deal, really, but time consuming to fix.     Ben has been very conscientious about fixing any similar mistakes promptly and "off the clock".

After the North wall was made right, we then turned to assembling the four roof walls on the building.    As the sun began to set over the Tucson Mountains, our intrepid builder Ben, architect Ted, and I succeeded at last in getting the last bolt in the last roof wall set in place.    The careful, continuous checks that we had made, making sure that each roof wall was as flat, plumb, and square as possible, paid off: the roof walls went together easily and accurately.

"As the Sun Sets Over Lizard Hollow Observatory..."

(Wrong movie - sorry!) All but the North roof wall have been bolted together and placed on to the rails in this picture taken about 45-minutes before sunset. By shortly after sunset, all four walls were up on the rails, bolted together, and the roof rolled nicely down the entire length of the rails.

Finally, working against encroaching darkness, Ben cut slots in the North and South roof walls to allow the rails to pass through them.    Getting this done right and carefully took a while, but the result was worth the effort as we were able to easily move the roof from one end of the rails to the other, with minimal binding.     The residual binding can be eliminated more easily in daylight tomorrow.    The big accomplishment for the week was in moving the roof down the rails.

February    8, 2000 - Triangles:     A windy day, and we began work later than usual.    We laid out the roofing sheet metal on the ground as it will be assembled on the roof, both to inspect it for shipping damage and to measure the exact size of it.    There are some small areas of abrasion on both surfaces of the metal, but it measures out as expected.     We then cut out four large triangular pieces of plywood which will be attached to the top surface of the roof walls at the corners.    This will provide added rigidity, especially in keeping the building square as it is pushed manually down the rails.

Ted has assumed day-to-day supervision of the project now as there are many real-time architectural design decisions to be made now.    Among these are the exact amount by which the triangular corner pieces overhang and support the edges of the roofing metal; the final adjustments to the squareness of the roof and how well it runs down the rails; the final design of the flashing at the rails so as to keep out blowing rain (of which we have a lot in July through September); and many other small design issues which are certain to arise near the project's end.

February 10, 2000 - Problems, Problems, etc.:    Some problems with the roof assembly design have come up.    First was that the South end of the roof, which has the cut-out to allow the roof to pass over the telescope safely, sags in the middle and binds against the sill plate.    This was solved by adding a taught metal cable, with turnbuckle, stretched across the roof wall and immediately underneath the 4"x6" support beam.

Other problems relate to the roof, and include: the roof not remaining parallel to the rails while being rolling down the rails ("racking");    an undesirable amount of play between the wheels and rails; the heaviness of the roof in terms of being able to move it manually.    I can move the roof down the rails easily, if a bit clumsily, but I doubt my ability to move it alone once the roofing metal is attached; if I can't move it alone, a winch will be needed.

Another problem was also apparent: The triangular supports for the roofing metal are warped, an expected problem with plywood.    Ted has made some plywood-and-2x4 corbels which will be attached under them to support and straighten them out.     Connecting the corbels to each other and to the triangles will be a 10' length of 2x4, one each at the North and South roof walls.

On a more positive note, the building is pleasing to look at, in proportion and overall shape.     The rails extend some distance beyond North end of the building, and, together with the square metal support beams at the rails' end, present a very nice sight, with a very pleasing Japanese feel about their appearance.

Much time has been spent over the roof-related issues without finding good solutions to them yet.    A major redesign of the roof/rails assembly is not out of the question, but simpler solutions will be sought before resorting to that.    We are taking off the next five days to get our breaths and sort these remaining problems out.

Of equal concern to me is the delay these problems have caused in getting an electrical supply out to the building.    To do that involves digging a three-foot deep trench about 30 feet in length and laying conduit in it.    Originally I had thought of running a network cable in the same trench so that the telescope could be controlled remotely in the future.    I abandoned that idea as the total length of cable required would be in excess of 115' and would also involve significant effort to get it into and through (or around) the house.    Any future remote-control facility will be via a radio-linked network, not via cable.

Remaining to be done is the installation of the louvers in the roof walls and in the entrance door; these two items will be among the last items on the punch-list to be done.    Before we resume work, the entire roof structure, including the corbels, needs to be waterproofed.    If time permits, I'd also like to waterproof the building frame studs.

So many problems are coming it us when we are so close to finishing the observatory that I am very discouraged.    In addition, I have been evaluating some commercial and shareware astronomical software for the Observatory's use, and have found it to be uniformly shoddy or that it doesn't quite do what is needed.    In addition, some software restricts the functionality in a ridiculously brainless way, sometimes to a very silly level.    Comparing my own experiences with this software to reviews in, for example, Sky and Telescope magazine, convince me that the reviewers either had a different version of the program or they are not presenting the complete picture.    Perhaps one of the useful things that Lizard Hollow Observatory can do is to post objective reviews of such software.

Today, I am very weary of the construction process and increasingly impatient to get the telescope installed and operational.

February 13, 2000 - The Measurements and The Checkings:    Unable to keep away from the Observatory, Ted and I measured the siding metal to ensure that the correct sizes and amounts were delivered, and we measured the roof wall dimensions for the flat sheet metal sheathing that must be ordered on Monday.     Yesterday, I found some thick Berber outdoor carpeting on-sale at Home Depot and brought home a 10'x12' piece of it with which to cover the Observatory floor; this is insurance against Ole Fumble Fingers here dropping valuable pieces of glass, like eyepieces, or equipment.

To our surprise yesterday, duplicate pieces of sheet metal siding were delivered.     The pieces are not all of the exact same sizes, but fortunately they are all slightly larger than needed.    The roofing metal is ok, in the amount and close enough to the sizes ordered.     The invoice which accompanied the shipment is indecipherable, which will necessitate a call to the supplier on Monday to ensure that they did not charge for the extra metal sheets and to complain about the sloppy measuring job done by the manufacturer: the lengths of the sheets vary by up to 0.5", so some will have to be trimmed down to size.    The delivery guy off-loaded the metal, presented the invoice, collected my check and left in a big hurry before I knew what was happening.

A fortunate discovery:   The roof width is nearly 2-inches wider on both sides than the building walls, so we will be able to extend the roof sheathing down below the level of the rails and top sill plate.    This will cover the rails and provide a measure of protection from rain and wind.

I must get out to the Observatory tomorrow morning and start waterproofing the roof walls, but today I am going to explore a new bar in the neighborhood, Woody's, and enjoy a few gin-and-tonics while relaxing in the warm sun on the patio, and I hope participate in witty and intelligent repartee with the other habitués...

February 14, 2000 - Playing Catch-Up:    Today I spent waterproofing most of the roof, door, and some of the studs adjacent to them.     This involved using a useful little device, available at Home Depot for about $4 - a paint roller with a built-in spatter-catcher for use when painting vertical surfaces above one's head (it worked pretty well, but didn't completely eliminate the little spots which accumulate on my glasses and help make painting such a loathsome task).    The waterproofing must be finished and dry before we can measure for the flat metal sheathing which will cover and protect the roof, so it's back up on the ladder tomorrow!

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