Clever idea. I wonder if the flex properties etc are stiff enough? If you use it, please report back.
It wasn't my idea, its been mentioned several times on a number of forums (finding a disk brake with the appropriate center hole to fit the mount). I've just been going through the painstaking process of finding an Australian supplier for an appropriate disk brake and this is what I came up with.
Everyone I've seen using disk brakes for this application says that they are more than capable of handling the loads.
Here's the 'rats cage' before I sink it into the brick pier:
I got a steel fabricator to drill the holes in the disk brake for $10. Next I'll drill a small hole for a bolt for the polar alignment adjustment, and then paint it with some rustproofing undercoat before giving it a white finish.
Last edited by Michael_Bibby; 06-10-2022 at 12:55 AM.
Yup, thats where I'm at now: planning on building a housing so that I can keep the mount on the pier permanently. My main concern is with the summers here: it gets very hot and humid (up to 45 deg). I was thinking about something similar to what you did but wanted to go one step further by having two covers, one on the inside, made out of plastic, which is completely sealed, and one on the outside, which allows for air circulation (aided by a cpu fan powered by a solar panel). Of course, the idea would be to put some 'gel packs' inside the first container to keep the moisture levels low). Any thoughts?
Heres a dry fit of the inner plastic container (a bin!):
Last edited by Michael_Bibby; 16-10-2022 at 06:01 PM.
Just a quick update on what I ended up doing. I had to scrap my original plan of using a round bin because the scope would have hit the base plate, so I instead used a bin from K-mart that has a rectangular footprint so that it is large enough to cover the mount but doesn't protrude too much on the east and west side of the pier. This is pretty much water tight. I then made a shade cover out of coreflute with a pvc bend joint to allow some air circulation. So far its worked well: the mount stays nice and dry, and doesn't get hot. Don't know if I will really need to go to the extent of installing a solar powered fan to help circulate the air. The coreflute cover is a bit flimsy and so I'll probably end up rebuilding it properly out of plywood and fashion it in the shape of a TARDIS (I'm really wedded to that idea!). I'll add some 'tie down' system of some sort to further secure the covers to the base plate.
Just a quick update, I've replaced the makeshift coreflute shadecover with a plywood shadecover and installed the solar panel and fan, just in time for summer. When I had the coreflute cover the mount was getting pretty warm (it was semi-transparent and let a lot of light through to the inner plastic container), whereas with the plywood cover the mount hardly gets warm even on very hot days (I really think it would get warmer if I left it in the house!). I make sure to wipe all the dew away after a viewing session before putting the covers back on and put a moisture absorber in the inner plastic cover to soak up any excess. All in all its working perfectly, I have absolutely no concerns about leaving the mount out all summer. The only thing remaining is the TARDIS makeover...
Last edited by Michael_Bibby; 17-12-2022 at 03:20 PM.
Fibreglass and epoxy was also my first choice, but I opted for some generic 3mm Bunnings plywood and 3 coats of good weather proof varnish, for cost saving and simplicity. I probably will give it a couple of coats of exterior paint too. I just wanted a quick solution to last me the summer months and hopefully into winter, and then I'll probably end up making a whole new one like a TARDIS, but at least by then I'll have a better idea of failure points and design improvements.
EDIT: good idea using epoxy to seal just the edges of the ply, I might do that next time.
Quote:
Originally Posted by LonelySpoon
An old guy at the paint shop said to me "If it's outside, and made of plywood, water will get inside"
I was after exterior paint for my dome, and he was right.
Seal all the edges with figreglass epoxy, and give it lots of coats of all-weather Solaguard type paint.
(Have you considered a metal bin painted as a Dalek?)
Neville
LSO
Last edited by Michael_Bibby; 17-12-2022 at 07:28 PM.
I've noticed that some sort of little borer is eating the middle layer of my 3mm skin. It doesn't seem interested in the thicker stuff, and it isn't termites.
The holes have been made on the inside of the rotating part.
I've squirted insecticide into the affected areas.
