Ray's Observatory Build

[RayD]

25 minutes ago, Davey-T said:

Well we've had a few earthquakes in Kent recently Ray so can't be too careful 

Dave 

Lol that's true Dave I didn't think about that.  I should have made that 16mm! 

[MikeP]

That is the neatest hole and reinforcing I've ever seen.  I'm really looking forward to seeing the rest of the build.  You are setting a high standard.

Mike

PS Is it my imagination of can I hear the strains of "Waltzing Matilda"?

[RayD]

10 minutes ago, MikeP said:

That is the neatest hole and reinforcing I've ever seen.  I'm really looking forward to seeing the rest of the build.  You are setting a high standard.

Mike

PS Is it my imagination of can I hear the strains of "Waltzing Matilda"?

Thanks Mike much appreciated.

I know what you mean with the depth, it felt that way when I was digging.  Look at this video of my Godson lol.

 

20161217_111815.mp4

[Davey-T]

Nice video Ray, looks like Escape from Colditz 

Dave

[Stu1976j]

Great progress, Far better idea to go slightly over the top than to underestimate it and end up regretting not making the hole bigger later down the road. 

[MikeP]

Love the video.  Brilliant.

Mike

[Oddsocks]

Don't forget to consider how you will get power and communication cables to the mount. Do you mind cables draping across the floor of the observatory or would you prefer an underground conduit between pier base and the control room?

If the later, then a ~50mm, or so, diameter conduit, solid or flexible, can be laid into the pier pad before the concrete is poured, bringing the mount cables out just beside the pier base, and keeping the observatory clear of cables to trip over or crush underfoot.

[Starlight 1]

That is one big  mole -hole !!!!!!

[carastro]

Can I suggest you put something around the decking, like chicken wire or something buried into the ground as well to prevent wildlife making a nice home underneath.  I didn't do that and I have had Rats and foxes and goodness knows what else under my observatory.  We have now put boarding around the edge, so long as they don't dig under it.

 

Carole

[RayD]

2 hours ago, Stu1976j said:

Great progress, Far better idea to go slightly over the top than to underestimate it and end up regretting not making the hole bigger later down the road. 

That was exactly my thoughts.  You very rarely hear of people complaining about over engineering things (apart from the cost of course), but it's much easier to do it now.

Mind you, as you know from your build, it ain't half hard digging all that stuff out by hand, especially when you're wrong side of 50!

[RayD]

1 hour ago, Oddsocks said:

Don't forget to consider how you will get power and communication cables to the mount. Do you mind cables draping across the floor of the observatory or would you prefer an underground conduit between pier base and the control room?

If the later, then a ~50mm, or so, diameter conduit, solid or flexible, can be laid into the pier pad before the concrete is poured, bringing the mount cables out just beside the pier base, and keeping the observatory clear of cables to trip over or crush underfoot.

Yes all decided on, but as always open to change following suggestions  

I'm definitely not keen on the idea of cables across the floor, so as suggested am having 2 conduits under the floor between the warm room and pier (with draw cables).  All the internal general wiring, lighting, sockets etc. I'm planning to do in a surface mounted galvanised 50 x 50 trunking as I'm not keen on running T&E in the cavities in sheds.  This will ill keep it out of harms way from any nibbling mice and lets me add stuff in the future as it will all be wired using singles.

The base is actually having a 400 x 400 x 200 kind of upstand on it which pops up through the floor framing bringing it up flush with the floor, so getting the conduits to the mount base is (he says with crossed fingers) pretty simple.

Thanks for the input, it's reminders like this on other posts that have helped me loads when planning the build.

[RayD]

26 minutes ago, carastro said:

Can I suggest you put something around the decking, like chicken wire or something buried into the ground as well to prevent wildlife making a nice home underneath.  I didn't do that and I have had Rats and foxes and goodness knows what else under my observatory.  We have now put boarding around the edge, so long as they don't dig under it.

 

Carole

Thanks for that great idea Carole.  I hadn't considered this but it will now be added, especially as the conduits to the mount are going to run under the base.

[RayD]

1 hour ago, Starlight 1 said:

That is one big  mole -hole !!!!!!

It's more like an elephant hole!  If I get any movement in my mount I think I can safely discount the base and look on the news for earthquakes 

[RayD]

2 hours ago, MikeP said:

Love the video.  Brilliant.

Mike

It was so funny, we were both laughing at how deep we'd gone, and we were almost both in tears when I jumped in and set all the re-bars in as I hadn't factored how I was going to get back out!  We ended up using some of the framing timber to make me a little ramp 

[SonnyE]

HUGE, Ray!

I was thinking... some archeologist in the distant future will be trying to figure out what an ancient civilization was doing with such a huge block. Instead of Stonehenge, it will be the Masters of Block.

I'd say you earned more Pizza and Non-Alcohol Beer.

[RayD]

10 hours ago, SonnyE said:

I'd say you earned more Pizza and Non-Alcohol Beer.

You know it SonnyE, that's exactly what happened 

[laser_jock99]

Looks like a solid enough base. Please, please don't ruin all the effort by balancing the mount and scope on four lengths of M10 studding as we see so often happen.......

[RayD]

14 hours ago, laser_jock99 said:

Looks like a solid enough base. Please, please don't ruin all the effort by balancing the mount and scope on four lengths of M10 studding as we see so often happen.......

Absolutely 100% not.

After much deliberation and searching I've found the only way to get exactly what I want is to make it, so I am having a custom pier built to my own specification,  which has a seam welded top plate. Just waiting for Bern at MA to send over some hole centre details for drilling and tapping. 

[RayD]

Right, only had a couple of hours spare today as back to the grindstone tomorrow so lots to do.

Going to try to get the concrete pour this week so had to get the little top hat box sorted.  I left the 1m x 1m template down, and used the bit that I cut out to infill the hole and cut a 400 x 400 square out of that for the bit that pops up in between the joists for mounting the pier.  I screwed some scrap 75 x 50 softwood to the edges so it could drop in to the template and get screwed down.

All a bit muddy today so things hard to keep clean, but hopefully once the pour is done and I can get some ground cover down (weed barrier and gravel) then this should improve.

As you can see from the below image, the replaced section now forms the top of the main block, and the extension is for the pier.  This has been levelled across so it is pretty well flush with the underside of the flooring.

I've got a poker (concrete vibrator), so whilst the concrete is being poured the vibrator will take out any air bubbles and settle it in to all the nooks and crannies.

Not a particularly eventful day but an essential part done.

 

[SonnyE]

I would only caution that you make sure the mud can't get away from you when it's poured.

Vibrating it in is a good idea. Just make sure your forms are strong and can't shift, float, or separate.

[RayD]

8 minutes ago, SonnyE said:

I would only caution that you make sure the mud can't get away from you when it's poured.

Vibrating it in is a good idea. Just make sure your forms are strong and can't shift, float, or separate.

Thanks SonnyE all points noted and much appreciated.  I think it should be ok as the actual hole is mostly clay, which seems to be holding fast, and the top and upstand etc. are all screwed together, so hopefully will hold fine (fingers crossed) but I will certainly make sure it's all very secure before pouring and now you've got me thinking more I'll probably put some additional ties in the template OSB just to make sure that doesn't have a tendency to lift, especially as I'm using the vibrator.

[SonnyE]

I would hate to see it blow out on you after so very much work and effort you put into it.

Best wishes for a Happy New Year and a perfect finish to your Observatory Ray.

Are you using diesel or a release agent on your forms?

I'm loving watching this come together for you.

[RayD]

10 hours ago, SonnyE said:

Are you using diesel or a release agent on your forms?

Didn't give that a thought to be honest?  Do you think this would be needed on the top part as I am using the sides of the "hole" as retainers for the main block?  I just assumed these would knock off, but if you don't think they will and diesel will work I can use some no problem.

[SonnyE]

4 hours ago, RayD said:

Didn't give that a thought to be honest?  Do you think this would be needed on the top part as I am using the sides of the "hole" as retainers for the main block?  I just assumed these would knock off, but if you don't think they will and diesel will work I can use some no problem.

I use to work around some construction in my job. Not directly on the construction, but holding clearances for some of the other groups (construction).

I got to observe how they formed up equipment bases, and all sorts of other concrete and as a rule, they usually used Diesel or a release agent sprayed on the forms (use a common chemicals sprayer) to help make them release from the concrete after the pour has completely set. Other methods use waxing the surfaces where the concrete will be in contact with.

The supplier of your concrete may have better recommendations based on your location and their experiences.

[RayD]

5 minutes ago, SonnyE said:

I use to work around some construction in my job. Not directly on the construction, but holding clearances for some of the other groups (construction).

I got to observe how they formed up equipment bases, and all sorts of other concrete and as a rule, they usually used Diesel or a release agent sprayed on the forms (use a common chemicals sprayer) to help make them release from the concrete after the pour has completely set. Other methods use waxing the surfaces where the concrete will be in contact with.

The supplier of your concrete may have better recommendations based on your location and their experiences.

Thanks SonnyE I'll look in to this