ROR Design


Shailesh Trivedi
 

This may be off-topic, I am the owner of an AP130, Stowaway, AP1100. and a soon to come Mach2. I am considering building a roll-off roof observatory 8 feet x 8 feet and 7 - 8 feet tall. 

Since we have so many distinguished APers here, can someone recommend whether a DIY with about $10K is possible and what pointers if any you can provide. I am considering a variable height pier from Pier Tech, which also provides RORs but not in the $10K range.

Thanks in advance for your help.

Shailesh


Stuart
 

Shailesh, I have two observatories with two piers in each. I think 8x8 is too small for two piers. My ROR is 10x14'. I bought the plans from SkyShed which are cheap. Then I talked to a local company that does industrial overhead doors and they offered some suggestions to upgrade the recommended 'C' channel that the roof would roll on. Then they came and installed the motorization. SkyShed plans didn't include ANY advice at the time for how to motorize their sheds.

Something I did that i "think" was clever: I dug a trench 8' long, 5' deep, 2' wide and poured about 9" of concrete in the bottom then set two 18" sonotubes at each end of the trench, started backfilling with earth then filled the two tubes to "level". The net effect is that the two piers are like a giant letter 'U' sticking a little above ground and flush with the floor. I think this is much more stable than two independent tubes as the base of the 'U' is like a massive footing for both.

In hindsight, I wish I'd put a third tube in the middle, between them (so a 'W') in case I reverted to just one rig in each observatory in which case I could put a single pier in the middle.

My second observatory is a 12' clamshell dome and with two refractors it is snug. So again, 8x8 seems too small.

On Thu, 29 Apr 2021 at 15:37, Shailesh Trivedi <strivedi@...> wrote:
This may be off-topic, I am the owner of an AP130, Stowaway, AP1100. and a soon to come Mach2. I am considering building a roll-off roof observatory 8 feet x 8 feet and 7 - 8 feet tall. 

Since we have so many distinguished APers here, can someone recommend whether a DIY with about $10K is possible and what pointers if any you can provide. I am considering a variable height pier from Pier Tech, which also provides RORs but not in the $10K range.

Thanks in advance for your help.

Shailesh


ROBERT WYNNE
 

I'm inclined to agree with Stuart. 8 X 8 X 8' is not high enough to accommodate your system. However, Stuart provides a clever workaround though he uses it differently. You could dig a 4-5' w/ 2' thick concrete footing for your setup. Though the excavation ought to be a full 8' diameter or whatever diameter will support your dome. Though it's hard to say if you won't encounter some obstruction to viewing with a lower than normal platform. -Best, Robert

On 04/29/2021 1:32 PM Stuart <stuart.j.heggie@...> wrote:
 
 
Shailesh, I have two observatories with two piers in each. I think 8x8 is too small for two piers. My ROR is 10x14'. I bought the plans from SkyShed which are cheap. Then I talked to a local company that does industrial overhead doors and they offered some suggestions to upgrade the recommended 'C' channel that the roof would roll on. Then they came and installed the motorization. SkyShed plans didn't include ANY advice at the time for how to motorize their sheds.
 
Something I did that i "think" was clever: I dug a trench 8' long, 5' deep, 2' wide and poured about 9" of concrete in the bottom then set two 18" sonotubes at each end of the trench, started backfilling with earth then filled the two tubes to "level". The net effect is that the two piers are like a giant letter 'U' sticking a little above ground and flush with the floor. I think this is much more stable than two independent tubes as the base of the 'U' is like a massive footing for both.
 
In hindsight, I wish I'd put a third tube in the middle, between them (so a 'W') in case I reverted to just one rig in each observatory in which case I could put a single pier in the middle.
 
My second observatory is a 12' clamshell dome and with two refractors it is snug. So again, 8x8 seems too small.

On Thu, 29 Apr 2021 at 15:37, Shailesh Trivedi < strivedi@...> wrote:
This may be off-topic, I am the owner of an AP130, Stowaway, AP1100. and a soon to come Mach2. I am considering building a roll-off roof observatory 8 feet x 8 feet and 7 - 8 feet tall. 

Since we have so many distinguished APers here, can someone recommend whether a DIY with about $10K is possible and what pointers if any you can provide. I am considering a variable height pier from Pier Tech, which also provides RORs but not in the $10K range.

Thanks in advance for your help.

Shailesh

 

 


Shailesh Trivedi
 

Thanks Stuart, I reached out to you separately offline.


Shailesh Trivedi
 

Robert,

8x8 base is my space limitation, my pad can be 9x9 max. The height of 8 ft is ok since my tallest TEC 180FL in Park 3 is 62 inches off the concrete, so 96 inches should provide more than enough headroom. Stuart has two piers, I have only one.

Shailesh


ROBERT WYNNE
 

True all that. Plus I was thinking of adding a solid concrete platform to isolate those intermittent bumps you might get from traffic - you don't really need all that extra concrete except for continuity. The 180, if you need to walk around it during a session may be tight. You could get away with a 4' diameter 2' thick isolation platform poured over sand. The best isolation platform set up I've ever seen is 4" X 4' oak driven into an isolated sand box over which a 2' thick concrete pad was poured - very little external vibrations even at 25 Angstroms. -Best, Robert

On 04/29/2021 2:41 PM Shailesh Trivedi <strivedi@...> wrote:
 
 
Robert,

8x8 base is my space limitation, my pad can be 9x9 max. The height of 8 ft is ok since my tallest TEC 180FL in Park 3 is 62 inches off the concrete, so 96 inches should provide more than enough headroom. Stuart has two piers, I have only one.

Shailesh


Stuart
 

Robert I have a friend who's pier is bolted to a dome of the Canadian Shield poking out of his land in rural Ontario. I suspect his pier is mounted on something north of 100mm tonnes. Pretty stable!


On Thu, 29 Apr 2021 at 18:25, ROBERT WYNNE <robert-wynne@...> wrote:
True all that. Plus I was thinking of adding a solid concrete platform to isolate those intermittent bumps you might get from traffic - you don't really need all that extra concrete except for continuity. The 180, if you need to walk around it during a session may be tight. You could get away with a 4' diameter 2' thick isolation platform poured over sand. The best isolation platform set up I've ever seen is 4" X 4' oak driven into an isolated sand box over which a 2' thick concrete pad was poured - very little external vibrations even at 25 Angstroms. -Best, Robert
On 04/29/2021 2:41 PM Shailesh Trivedi <strivedi@...> wrote:
 
 
Robert,

8x8 base is my space limitation, my pad can be 9x9 max. The height of 8 ft is ok since my tallest TEC 180FL in Park 3 is 62 inches off the concrete, so 96 inches should provide more than enough headroom. Stuart has two piers, I have only one.

Shailesh


ROBERT WYNNE
 

I should hope so. Most of us don't have the benefit of the Canadian Shield as a platform for a pier. Though it may be prone to things like heavy machinery bumping down the road. Here in the San Francisco area we would use isolation tables for precise permanent installations due frequent shakes. But if you have the Canadian shield you may as well use it. -Best, Robert

On 04/29/2021 3:37 PM Stuart <stuart.j.heggie@...> wrote:
 
 
Robert I have a friend who's pier is bolted to a dome of the Canadian Shield poking out of his land in rural Ontario. I suspect his pier is mounted on something north of 100mm tonnes. Pretty stable!
 

On Thu, 29 Apr 2021 at 18:25, ROBERT WYNNE < robert-wynne@...> wrote:
True all that. Plus I was thinking of adding a solid concrete platform to isolate those intermittent bumps you might get from traffic - you don't really need all that extra concrete except for continuity. The 180, if you need to walk around it during a session may be tight. You could get away with a 4' diameter 2' thick isolation platform poured over sand. The best isolation platform set up I've ever seen is 4" X 4' oak driven into an isolated sand box over which a 2' thick concrete pad was poured - very little external vibrations even at 25 Angstroms. -Best, Robert
On 04/29/2021 2:41 PM Shailesh Trivedi < strivedi@...> wrote:
 
 
Robert,

8x8 base is my space limitation, my pad can be 9x9 max. The height of 8 ft is ok since my tallest TEC 180FL in Park 3 is 62 inches off the concrete, so 96 inches should provide more than enough headroom. Stuart has two piers, I have only one.

Shailesh