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My Suburban Concrete Pier + cem120 + 12x12 Deck + Nexdome Build thread

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#1 markm75c

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Posted 17 July 2019 - 09:57 PM

At this point, thanks to the great community and help here on CN, i've gotten 90% of things straight on my build and its starting to move forward (from my other topic specific threads).  So i'm going to document the process and what i ended up doing as we go along here.

 

Background:

I live in the suburbs in a Bortle 5 sky zone (i think 19.8 magnitude or so on the scale), mainly due to a small shopping center pumping out light to my East 2 blocks away.  I'm blocked to the direct west by trees (i can catch venus at certain times of the year in the west next to the trees though).  To the north there is another smaller lot that puts up a bit of low angle light, but higher up its fine. 

 

It had become clear we probably werent moving for at least 5-10 years, with multiple kids in the same district for awhile at least, so it made more sense to just go for it from the current house.

 

Here is a pano shot looking due S (east to the left, and WSW on the right):

yard-PANO.jpg

 

This is where i've been setting up the scope day after day, looking north (that light above their wooden fence does minorly light up part of the upper yard, which i might try to ask them about, but most targets arent North):

northview.jpg

 

The light at dark:
northnight.jpg

And looking south (i dont think my pool light hurts anything from that low level):

southnight.jpg

 

 

So all that said I opted to go for the NexDome.  I looked at other options, but it was the most economical for what it can do, with its higher walls, light blocking and cheaper overall to automate (which i will at least automate the dome portion within a few months).

 

I decided i would do a 12x12 wooden deck as the flooring, along with a pier in the ground (concrete) extending up through the deck and isolated (24x24 footer).

 

Here is a shot when i first began manually digging/leveling the ground:

ground.JPG

 

 

I initially thought i would do concrete above ground preformed blocks so i could just pick up the deck and take it when moved.  I decided that wasnt practical and I was concerned about any movement.  In SW PA the winters can be harsh.

 

So the digging commenced further and now I have things mapped out and dug.  I'm still debating if ill slice the steep cliff edges of the surrounding grass to all landscaping material and rocks to lay there, or just leave it straight up and down (leaning towards slicing).

I'm a little concerned about draining coming from the back end rolling down under the deck, so i might create a channel 1 foot wide maybe 6" deep with rock/landscape material straight under the center of the deck out the front.

 

I have a ton of excess dirt.  I may put up an add for free fill or get my contractor relative to take it away.

 

Here is the layout with some lines to show things:

stringlayout1.jpg

 

Here is the pier footer so far, dug down about 2.5 of 4 feet (manually, it wasnt that bad till i hit clay, i will be able to finish by hand though)

 

pierhole1.jpg

 

 

The pier footer will come up to meet the deck surface at what I estimate to be around 14" high off the ground.

To make the footer ill use 3/4 plywood sheathing from lowes x 4 and hold it up using a few rebar pounded in the ground (unsure what to do about the corners leaking concrete, maybe nailing the corners together).

 

We have pretty easy going city codes, so i didnt need to worry about the frame being 12" or even 10", however, i went with 8" and for a low level deck really is plenty though you will get differing views out there.

The base of the frame will be about 4" off the ground, and that makes it 14" above ground for the 5/4 board on top (decking planks).

 

Here is a rough layout of the deck and joists.  I wont have double boards on the two sides as shown and probably not double near the pier either, otherwise the same, 16" on center for each joist. (there will be a post on each side of the middle area as well).  I'm aiming for at least a 2" spacial separation around the square area where the pier comes up through and use foam to fill the void to prevent critters.

deck-joists.JPG

 

Here is the list of materials used for the deck:

 

2x8x12" framing board and joists x 14 (so 10 for joists/boxing in the pier area)

 

4x4x8 x 4 for posts (which ill dig down 2 feet which should be good enough, yes 4 foot is the frost line but our bigger pool deck only went down about 3 feet with 4 foot high posts and its been solid; i plan on wedging the posts in the hole temporarily and putting on the 2x8 board making it level and then adding 1/2 the hole with high strength quickcrete and then about 4 inches of water/1 gallon and let set making sure plumb)  Ill do the frame on 2 sides so i can lay a 5/4 board across to get the exact deck level to be able to add the frame for the pier footer.

I plan on using about 10 posts, maybe 3 on each of the sides and a few near the pier area.

 

5/4 x 6 x12 footers x 27  **for the decking.  There is debate here, once i have it up with the dome, i might consider laying plywood ontop of the 5/4 to seal off from critters and then use the interlocking foam mats everyone uses for flooring, along with rubber padding along the edges of the dome, as well as caulking on the outside of the dome (the 27th is a spare)

 

60lb high strength concrete mix (again, using 1/2 bag in each post hole)

 

2x4x8 x 4 :  for creating a frame around the pier to pour the cement and keep it straight (pvc pier) and one piece to tap at the concrete as its being poured in.

 

3/4" plywood sheathing 2x4   x 2 (for making the box around the pier 14" high)

 

2x8" 18 gauge triple zinc joist hangers x 16

EDIT: galvanized steel should be used, so these x 16

 

Deckmate 3" ceramic 5lb screws (for screwing in joists and for the 5/4 boards up on top and temporary hold screws for posts before carriage bolts before cement)

 

1.5" joist/framing nails galvanized 1lb

 

0.5" hillman 8" carriage bolts and nuts and washers :

 

At each post ill use two carriage bolts one above the other for support.

 

 

 

Steel rebar ties (for making hoops/loops around the rebar cage that ill make out of 4 rebar)

 

4' rebar x 8 :  this will be for 4 rebar each, a cage down in the footer hole (which will only make it to the edge of the surface) and also for inside the PVC pier which will start 3/4 the way up and extend out 1 foot down under the pier tube and insert into that 14" area above ground

 

Hillman 5/8" x 12 L bolts:   These are for the mounting plate going down into the concrete, with the plate about 1" above the PVC so there is room to tighten the nuts.

Hillman nylon lock nuts (zinc): x8  unsure if just these and washer or the standard nut + lock washer + washer (i didnt see stainless steel at lowes, my closest option around)

Hillman 5/8 split lock washers x8

Hillman 5/8 standard washers zinc plated? x 8

Hillman 5/8 nut zinc x 8

 

PVC 12" diameter for the pier and 4 foot long initially:  Online there are some sources that will ship, as cheap as $139.. I found a local source and it was $61 total for 4 feet, likely cutting it to around 42-43" (maybe with 1" submerged into the footer, unsure)

 

Possible flooring options:

On top of the 5/4 board:

  The plywood yellow pine PT  or PT regular

or

Interlocking tile option $39 12x12 qty 10

96 square feet walmart foam tiles  $69.99 (most likely will go with this)

 

Wall foam along the floor and or insulated on the nexdome walls:   Harbor Fright "workbench mat"

 

 

Now onto the mount + mount plates:

 

So i've opted to go with the CEM120 mount, for future proofing.

Right now yes i have just an 8SE plus eventually a guide scope, but in the next 1 year i plan on going 11 edge + hyperstar F2 + maybe a 130ish mm refractor for mostly optical

 

This will be my first GEM so ill be learning alot quickly.

 

The CEM120 is a beast of a mount, supporting 115 lbs payload.  I looked at hdx110 and other options, even the CEM60 before opting for this, based on payloads others have ended up at (beyond 50 or even 60lbs in some cases).

 

There is a mount plate diagram online and it looks like this.

 

a88de34e5aa9f5fe9b52cc4257af4fab0bfb2114

It boils down to the plate itself being around 8.25" x 8.25 (diagonal around 11.67").  So the points of the square will be very close to the edge of the 12" pvc.  

 

I'm still weighing options, but I will likely go with a single plate solution, putting the L anchor bolts somewhere at around 1.4" - 1.6" from the edge (maybe 4 of them), yes this is closer than the recommended 2" edge to bolt edge, however, being as the cement is in PVC it shouldnt be an issue.

 

I'm either going with 3/4-1" aluminum #6061

Or 1/4 or 3/8" steel a36

likely 1/4 steel

 

So the next things coming are, the cem120 and a temporary $129 ioptron adapter plate to use a template is inbound, meantime ill begin to sink 4 posts in the ground and finalize the pier hole/footer boxing.  Note you could use the $129 ioptron adapter plate directly on top instead of the a36 steel disc option, probably using turnbuckles in place of the nuts they have in the adapter plate.  I've decided ill just go for the 12" disc however, drilling the holes in it.

 

I checked on cement pricing for 22ish bags of 0.64cu ft high strength (4000+) cement + renting and delivery and its around $220, i found a local delivery truck for $280 and i'm going to go with this.

 

First i need to make sure the mount is done (need to order the plate and drill the appropriate holes, straight through using only nuts/washers) and then size up things to determine the pvc height (pier height).

 

The nexdome recommended height is 53" from the ground to the center of the ota as in this photo:

8a866a_3b8131b9894b45dc8143c2217d989dbf~

 

My mount should be about 9.4" at 40.5 latitude from the base to the top (though seeing photos i really think its much higher than the number ioptron gave me).

 

I also need to make sure the mount plate is set with true north in mind (still need to check on that, if its not just aimed at polaris).

 

 

Other things I have to do is rent a ditch witch and run roughly 120 feet of electric from my garage breaker box to the dome / deck area.  I figure on doing this before all the floor boards are in place and try to trace a circle on the deck so i can put the first junction point for electric / data at one corner, though i'm unsure whats best there, or maybe just to the corner of the deck in a weatherproof box for now, then breakout from there to the pier.

 

Ill run electric (10 gauge?) 120v in electrical conduit (i assumed it had to be the grey stuff) and the data (3 gigabit runs) in 1.5" or so standard pvc (same ditch just spaced apart).  The gigabit will make things like teamviewer a little more responsive than my wifi can be.

 

I'd like to figure out gig to usb, but nothing in 3.0 seems to exist or does but costs $1k.

My office space in the house is where i can run everything from, especially on cold nights.

 

I've been using a laptop and leaving it outside for now and might still do that in the dome, but eventually i'll probably get an i7 Nuc and leave it in the dome 24/7.

 

 

 

EDIT/update: added info for the nails/deck screws for completeness.

 

 

 

More to come.


Edited by markm75c, 18 July 2019 - 11:53 AM.

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#2 GrandadCast

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Posted 17 July 2019 - 10:56 PM

You may want to check your hangers type. From what I remember galvanized should be used with certain types of tread wood. You appear to select zinc. Also, your wood selection states "Use building code approved fasteners and hardware. Hot-dipped galvanized or stainless-steel is recommended". Hate to see your hangers rust out.

Jess



#3 markm75c

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Posted 17 July 2019 - 11:35 PM

You may want to check your hangers type. From what I remember galvanized should be used with certain types of tread wood. You appear to select zinc. Also, your wood selection states "Use building code approved fasteners and hardware. Hot-dipped galvanized or stainless-steel is recommended". Hate to see your hangers rust out.

Jess

Good catch on that. Thank you. I'll swap them out for hot dipped galvanized and make sure the nails are too. It's harder to find things like nylocs hot dipped but those are in the dome. 


Edited by markm75c, 18 July 2019 - 09:52 AM.


#4 markm75c

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Posted 18 July 2019 - 10:21 AM

I was able to find a local fabrication place that can cut the a36 steel and put the holes in it.  Around $45 total (vs $25 for the 1/4" a36 ebay source), but worth it.  I should have the ioptron adapter plate/template tomorrow and by Tues have everything ready to pour concrete.

 

I just need to decide on the anchor bolts if ill go with 5/8" or drop to 1/2", many seem to suggest 1/2" is plenty and it would take up less space with the nuts on the plate.  I've decided ill just use nyloc nuts and a washer however for everything.

 

The ioptron cem120 comes with bolts but not the nuts/washers.  I also need to double check that for the anchor bolt, the washers i have linked above are the right ones or big enough.


Edited by markm75c, 18 July 2019 - 11:27 AM.


#5 John Fitzgerald

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Posted 18 July 2019 - 05:23 PM

If you make a round and smooth pier where it comes through the floor, you can cut a round hole in a thick rubber mat and stretch it over the pier, and it will fit tightly against the pier and floor and prevent critters.  It looks neat and you can avoid the foam, which always flakes, and might not stay in place over time. 

 

That's what I did.  If you are interested, I will post a picture of it.



#6 DuncanM

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Posted 18 July 2019 - 06:28 PM

 Are you buying the iOptron CEM120 adapter plate just to use it to mark your holes?

 

Once you get the mount, you can just set it on some plywood or cardboard and trace out the template.



#7 markm75c

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Posted 18 July 2019 - 08:22 PM

 Are you buying the iOptron CEM120 adapter plate just to use it to mark your holes?

 

Once you get the mount, you can just set it on some plywood or cardboard and trace out the template.

Mostly I am, thats also true.  The cem120 comes tomorrow and the plate.  Ill trace it at first, though i was nervous my trace would be off.

 

I'm taking either the trace or the adapter plate to the local fabrication place tomorrow or monday.

 

If the trace looks too close to the edges for the jbolts then I might see if they can do like another CN user had done.  He has his ioptron plate attached to an 8 inch plate below it (on 12" concrete) and it worked out well. 

So at least as of now i have a few options.

 

It will probably be sunday night or monday before i can get back to post installation and framing, as the weather here is getting brutal hot.  Still hoping to pour cement by end of next week or week after.



#8 markm75c

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Posted 19 July 2019 - 01:30 PM

I may be making a change to the pier diameter.

 

I think i'm probably going to reduce it from 12 to 10".

 

Even though i dont think at 40.5 latitude ill have issues with the telescope or in future telescopes hitting the concrete (near zenith), this will ensure no issues.  2" inches more of floor space in the nexdome is a bonus as well.

 

I"m also going to go with a 2 plate solution, as the jbolts would only be 1" from the edge with a single 12" steel plate, too close.

 

The two plate solution inspiration came from CN member amoncayo and his configuration (I wont use the ioptron plate, but rather ill just get two 3/8" a36 steel plates and have a local shop connect them and drill the holes)

Either way 10" plates no matter 12" or 10", only change is where the jbolts come through the lower plate, roughly 1" from the edge if 12" pier, 2" if 10

doubleplate.jpg


Edited by markm75c, 19 July 2019 - 01:31 PM.


#9 markm75c

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Posted 19 July 2019 - 09:03 PM

Moving forward on the 10" pier change:

I decided to make a mockup out of cardboard of the 10" 3/8 or maybe 1/2" thick a36 steel plate that ill use for the lower plate as seen here.  I made a 2" radius to outside of the bolt to represent going from the edge of the concrete (well really to the pvc of the 10" pvc that ill use at this point, not 12"). 
I wasnt exactly sure which 3 positions were optimal but this is what i came up with (you can see some other positions with smaller circles) and i think its close to how yours is arranged, although on yours probably only 1" to the wall of the bolts since your pier is 12":
cardboard3.jpg
 
Then for the upper plate, whether it just ends up being the ioptron plate or a less expensive a36 plate (3/8" or 1/2" thick again) but tapped, the m10's might represent a bolt going through to the circle lower disc (i guess ill keep the square shape above). 
Question being are m10s big enough as 3 support bolts (i think Dan said he may have drilled those m10's bigger, so maybe m12s):
 
cardboard2.jpg

#10 markm75c

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Posted 20 July 2019 - 08:49 PM

I've redone things and included the 5/8" jbolts, nylon lock nuts on top, double washers and lock washers with regular nut on bottom.  Double because if they can slot the plate to allow position changes on the bottom two jbolts it will firm them up.
 
bottomplatemock1.jpg
bottomplatemock2.jpg

#11 markm75c

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Posted 23 July 2019 - 09:59 AM

updating my main thread here:

 

Tomorrow is finally the day ill be stopping by the machine shop fabrication shop.

 

I'm still strongly in favor of the first option, the dual plate option, roughly 4" thick, with 9.4 as the nexdome mount height from the 53 that puts a 10" pier at 39.6" or so, so ill drop to 39, shouldnt hurt, assuming the double plate is 4"

 

Option b, i havent ruled out, might be a steel tube with flanges on the 10" pier (unsure if the bottom needs to have leveling ability or not and unsure if it needs 3 or 6 bolts around the bottom, like this:

post-1-14070953778622.jpg

The last option would be to give the machinist plans for a metal pier, like the skyshed one and create a full metal one at 43.6" high to the floor base (no rat cage/additional spacing).  I'm going to show him that idea tomorrow as well.


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#12 markm75c

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Posted 23 July 2019 - 02:45 PM

Speedsters design idea on pvc pipes coming out of the main column for data and electric is what i'm planning on, but i might need to alter things:

post-298771-0-39472100-1562623368.jpg


I'm thinking ill have to make the outputs at least, be under the 2x8 joist level so that i can run under the floor, so this means the tube needs to be longer by a good 10" i think (actually, i only will have 48-50" of pipe to work with, was planning on 39" above the deck)

Ill have that concrete footer, 4 foot deep 2x2 coming up to floor level then from there up was going to be the tube, i guess i could make the footer only go as high as the bottom of the 2x8 joists  Then i could have the pvc tube going down in the floor with the data/electrical pipeline coming out under the joists to route wherever its needed


Edited by markm75c, 23 July 2019 - 02:46 PM.


#13 markm75c

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Posted 23 July 2019 - 09:38 PM

Frame in place (mostly) tonight, more bolts to drill.

 

My original target was 4" above ground below the joists (2x8's) but i went a little higher to allow for some conduit running if not just going through joists.

 

Back end is an avg of 5" and front about 6.5.

 

frame1.jpg

 

Im likely to leave the front right post as is and not saw flat, as i could use it for a security camera and a power box.


Edited by markm75c, 23 July 2019 - 09:42 PM.

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#14 Michaeljhogan

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Posted 25 July 2019 - 05:17 PM

no help from anyone total newbie

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#15 Michaeljhogan

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Posted 25 July 2019 - 05:19 PM

no help from anyone total newbie every man for himself

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#16 Michaeljhogan

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Posted 25 July 2019 - 05:24 PM

From 2013 i did it just by looking at images no help

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#17 Michaeljhogan

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Posted 25 July 2019 - 05:27 PM

finished i still hold a grudge from useless so called astronomy community in Ireland not like america

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#18 Michaeljhogan

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Posted 25 July 2019 - 05:34 PM

The Cge Pro was a very good mount but soon became very outdated for CCDs Wireless imaging EAA etc

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#19 markm75c

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Posted 25 July 2019 - 09:10 PM

Updates:
 
I had to buy more supplies tonight.
 
I had to rewire my garage subpanel because an electrician shortcutted it years ago with 10-2 wiring from the main.  The wiring should have been 10-3 with ground.    
 
So today I rented a ditch witch which the local ace place delivers.  Total cost to have delivered for 4 hours around $175 with the delivery fee i think it was.
I trenched the path from right corner of the deck, which now has a good deal more done, including 8 of 10 posts in the ground.
My wiring for the observatory is going to come from the main panel in the house and on 10-3 with a ground as well.  Cost around $1/ft for uf-b burial type, down 24" with caution tape on top.  I ran a section back to the garage to fix the mess there.  In the garage/house will be a junction box on the other side of the wall followed by romex cable (same 10-3 with ground to the breakers).
 
At the deck post i'm using an LB electrical conduit (1").
 
The data is being run via electrical conduit, 1.5" for 3 gigabit ethernet cables and one bnc cable for a camera, along with a fish rope that will be left in case more is needed in the future.  
I'm using an LB Connector box at the deck and one going through the wall at the house (1.5")
So far it appears i needed at least 10 sections of the 10 foot pvc 1.5 (roughly $6 per pipe) plus some added couplers and 90 bends.
 
Both the electrician and the local supply shop agreed since the dome is the highest structure in the top of the yard, despite there being a ground at the main and flowing through, that i should have a ground rod up at the deck as well.  An 8 foot cooper one along with 6 gauge copper is being layed in the ditch up there or driven into the ground.
 
So the ditch layering is like this:
 
24" deep, first the ufb wire
Cover that with about 3" or 4" of dirt
Then lay the caution tape.
On top of this is the 1.5" pipe for data.
At the deck post beyond the lb is going to be a junction box on the outer post and from there under the deck ill wire to the pier and branch off to outlets as well as the breaker box/panel (probably 2 breakers).
 
trench1.jpg
trench2.jpg
 
 
Back to the deck update:
 


The pier footer is at 43 of 48" deep and 2foot by 2foot wide at this point.  I might just go with this for the footer, it should be deep enough.  All the posts on the floating deck around 26" deep with 2 bags of concrete per the outer 4 and slightly less deep and about 1.5 bags per post for the middle 3 supports.
deckhole1.jpg
 
I started to hit alot of rock, so it was hard to bell out the bottom wider, as it should be.  I was using a post hole digger (one man) for much of the last 20" of this, i happened to have already rented it for the other 4 holes so i figured why not.
 
footerhole.jpg


Edited by markm75c, 25 July 2019 - 09:23 PM.

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#20 markm75c

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Posted 25 July 2019 - 09:27 PM

I also visited the local fabrication shop.

 

I showed them skyshed piers and asked for an estimate to just go that route.  They wanted the same price $750.

 

I showed them many of the 6ish inches high mini piers many use as spacers.  They wanted $300.

 

I showed them my original plan, lower steel 10" 1/2" thick plate with jbolts and connectors to the ioptron plate above.  They wanted $90 for the lower plate and likely the same if i replicated the ioptron plate.

I opted to just keep the ioptron plate (which is 1/2" thick aluminum btw).  Roughly 90-100 and another week before done.  However, i'm having them add slots to the lower plate so i can adjust for true north on the lower left and right jbolts (see previous images).

 

This means the concrete cant be poured for about 1 week.

 

*I've also heard that it might be a good idea to put insect netting below the deck boards.  That might be something else i add.

 

Possibly something like this netting here 4x7 for $12 at lowes x2  or this on amazon for $20


Edited by markm75c, 25 July 2019 - 09:50 PM.


#21 markm75c

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Posted 26 July 2019 - 11:10 AM

I still need to decide if i'm going to stick with the standard 53" (nexdome) off the deck to the RA/DEC axis on the mount as planned or maybe lose some horizon and go lower for the odd situation were i might have a side by side refractor that requires more length than an 8 or 11" sct.

 

I'm also probably going with 2" framing around the footer, then the pier from there up, this way i can put decking very close to the pier but not touching, minimal gap.


Edited by markm75c, 26 July 2019 - 11:11 AM.


#22 markm75c

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Posted 28 July 2019 - 10:23 PM

A few updates.

 

I've settled on the frame of the pier hole being around 1" above ground.  I got it put in tonight but its off center, nothing i can do about it.  I could add another 2x4 to the right but there would be concrete under that 2x4.  I could try moving it left, but it would be above air on the right.  I did manage to bell out the bottom slightly, overall its around 43" deep.  

 

I havent decided whether ill try to run pvc down the center of the 10" pvc pier or not (one for data one for power).  I might skip it and just strap any wires onto the side.

 

Either way ill have flooring over the footer but not touching the footer and not contacting the 10" pvc pier when done.

 

frameabove.jpg

 

framemeasure.jpg

 

holedepth.jpg

 

framewide.jpg

 

I'm probably going to go ahead and put most of the other joists up along with their joist hangers.

 

 

I also took a shot at true north calculations.  I placed my 8se scope / tripod behind the center of the hole, found polaris and came straight down to level.  I was able to target the rear fence and stick a stake in there, then use a laser pointer and put another directly in line to create an arrow.  

I then tried a compass app on android.  It had it more to the left, as shown by the wood in the photo.  I'm going to go with the polaris line of sight and hopefully the slots in the lower mount will be good enough to adjust if off.

 

polaristruenorthwood.jpg


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#23 MJB87

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Posted 30 July 2019 - 10:51 AM

Yeah, the smart phone compass apps can easily be off by 5 degrees or more.

 

When building my observatory I had surveyors already working on the property layout the observatory so the north wall faces exactly to the NCP. Glad I did. Just makes everything easier.



#24 markm75c

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Posted 02 August 2019 - 11:25 AM

I thought the fabrication and connection of the ioptron and lower plate would be done yesterday, they are still working on it.  As of now i have concrete scheduled for saturday the 10th still, hoping that the plate is done by monday so i can get to cutting the pier pvc to the right height (cant cut the pvc and subsequently make the rebar cage till i'm sure on the mount height).  I'm thinking of leaving the jbolts stick out a little longer under the lower plate and thereby lowering the concrete pier pvc by maybe 2" at most (for what might be 3" under the plate with those 5/8 jbolts).

 

Meantime i started grabbing some extras for the dome like lighting:

 

One single loop of 32 feet (need 24, unsure what to do with the extra 8 feet) color changing and brightness changing type here on amazon for $30

 

I might put them around the floor and not up around the wall edge, unsure.  Looks like i wont need an inline dimmer switch either, with these ones.

 

edit: they can be cut, tho they have adhesive, not sure i'd trust that, i guess ill need to figure out some sort of clamp to screw into the dome to avoid adhesive if any is needed (to maybe keep off the floor by an inch)

 

backtracking to the flooring interlocking matt tiles, i'm thinking i may go with 1" instead of 3/4" as i can embed wires more easily for ones i dont end up putting under the floor possibly.


Edited by markm75c, 02 August 2019 - 12:02 PM.


#25 markm75c

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Posted 06 August 2019 - 01:52 PM

Updating things here related to the double pier plate setup:

Well the local fabricator finally finished the bottom pier plate.
 
He mentioned that the washers i had included are too big (i think just for the top slots) as they were USS 5/8 washers. He says i will need SAE washers, which i'm guessing are still 5/8 variety but maybe smaller.  
 
I hope the smaller washers at least on top dont cause any issues.
 
I need to paint the steel plate.
I was going to use this rustoleum flat black paint.
 
He is making standoffs for inbetwen that are 1.25" in height, slightly more width between the plates than in the original idea, but I just wanted a tad more (and a tad lower pier, as ill make the jbolts stick out of the concrete slightly more).  I think instead of 4" from top of concrete to top of top plate i might be at 4.5 or 5" with 1.25" standoffs and slightly more jbolt out of the concrete.
 
Ill be picking it up today, i hope its stable.
 
here is the photo of it as of now (1/2" steel) with the slots for true north adjusting (matching dan's plate idea):
pierplatefab.jpg


Edited by markm75c, 06 August 2019 - 01:53 PM.

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