Thread: Pier Depths
View Single Post
Old 19-04-2022, 09:19 AM
glend (Glen)
Registered User

glend is offline
Join Date: Jun 2013
Location: Lake Macquarie
Posts: 6,721
There is no standard footing, as Al indicated, it depends on what you find when you start digging. Now honestly I think 350 a side is too small, mine is 600 a side. As far as depth is concerned, I would suggest 600 minimum, and if your on clay or sandy conglomerate type ground consider driving galvanised angle iron into the base in several directions, creating a porcupine type anchor system.
Your anchor bolts are easy, just install as you finish the footing pour, and you need to look no further than Bunnings for foundation J bolts. Obviously a level footing surface is nice but you can shim within reason if you need to.
I will point out that for equatorial type mounts, perfect leveling is not necessary, as your star alignment software will compensate.
Have fun, digging the footing is the worst part of an observatory build, when done by hand.

PS, you will get folks swearing that your footing needs to be a full cubic metre (1000x1000x1000) but they are fairly rare these days.
Reply With Quote