Pier Construction Question

[mariaone]

I have noticed that most diy piers have the pvc conduit for power and usb/comp cables running up the outside of the pier. my pier is being constructed from a 6" waste pipe filled with concrete and rebar and i was wondering if it would be better to run the conduits for the cables up the inside of the pier for a neater finish. or would this impact the structure of the pier too much. I'm not and engineer so unsure of the pro's and con's of doing it this way.

any advice or tips would be appreciated

[leelee970]

I ran mine on the outside so that I could add to it easier, you may find pulling a moulded plug through conduit difficult, and yes it would have some impact on the structure.

As long as the cables are tucked away then it really doesn't matter on neatness - after all you'll be in the darkness of wonderful clear nights.

[stem1989]

I would advice outside, it gives you full control if cables wear out or stop working, if they are in the actual pipe they are never going to move.

[mariaone]

i agree that i could tuck them neatly on the outside of the main pipe, my problem is im clumsy and thought if i hid them out of the way im less likely to trip over them or damage them, which is why i thought about running them in conduit up inside the pier. maybe this needs a bit more thought than i am currently giving it

[stem1989]

you could always run them outside of the pipe in pvc and under the floor and up again at your 'work station', I had thought about it but settled for duck tape to stop me tripping in the dark.

[mariaone]

ah ha! another clumsy person i did think about that but knowing me i would probably kick it by mistake if it was on the outside which is why i was going to put it well out of the way.

[leelee970]

I ran mine in PVC trunking and terminated the cable ends in an electrical socket with relevant outlets (USB, RJ45, D.C sockets).

If I started again I'd make sure the outlet sockets were facing downwards out of the electrical box instead of out of the side as I have knocked out the power plug to the mount on more than one occasion.

The other thing I should have done was make sure the underneath of my Obsy was rat proof - I keep chickens and the rats just love their readymade home next to the coop.

My worry now is that they will chew through the mains cable one day, but they’d only do this once.

[fondofchips]

leelee970 wrote- "My worry now is that they will chew through the mains cable one day, but they’d only do this once".

Only one rat will do this once, is there anyway you could get rat poison underneath the obsy and/or away from the chickens.

Don't make the underside of your obsy too comfortable/draught proof better cold it does discourage rats/mice.

If you put poison down put it somewhere where it attracts the rats away from your house/chickens as the poison itself can attract rats.

Best if it is near where the rats are coming from. Difficult as wildlife birds, hedgehogs etc also need to be protected.

If you have poison down all the time it clobbers the first rat & avoids an infestation.

I keep chickens but my main problem has been mice which are easier to deal with.

[Gina]

We keep goats and often have a rat problem. Rat poison in places where wildlife and pets can't get is generally keeping them down. You need to be extremely careful with rat/mouse poison to stop wanted life getting at it.

[stem1989]

I was worried about the issues when building my obsy with rats and mice but I had the base high enough that my cats could get under there and act as vermin control to prevent the things eating my wiring! and I haven't seen any...yet

[laser_jock99]

Another option is a steel tube pier with access holes top & bottom.

[leelee970]

Sorry to steal this thread, and thanks to everyone for your suggestions - I easily sorted the rat problem - although on going until the chickens go.

I've placed poison under the Obsy and have baited traps out each evening (covered to prevent most animals and birds from getting to it, and removed during the day).

The other thing that really worked well was wire wool in the holes - they hate chewing this.

And lastly I admit I've an air rifle that has been used - sorry to those that may find this last resort offensive or cruel.

[mariaone]

He he steal away. i won't have a problem with rats or mice as my obs is going in the country but i own a cat who can deal with them for me so no need for poison or traps just let nature deal with it

[Astrokev]

I plan to use a 250mm air con duct as my pier which I think is big enough to put a sizable PVC pipe on the inside to run any cables.

[mariaone]

im only using 160mm drainage pipe so was uunsure if plonking 25mm conduit inside it would weaken it too much. if i was using 250mm then i wouldn't worry about it

[Gina]

Certainly sounds fine to me What I can say is to allow a nice big pipe for the cables - there's always more than you think. I used 40mm plastic waste water pipe. Also, make sure any bend is an easy curve without any ridges so that cables will feed through as easily as possible. Also, put a good strong draw string/rope through when you assemble the pipework for pulling cables through and make it long enough so that there is still string/rope coming out at both ends when you've pulled a cable through. Then there will still be a drawstring to pull more cables through as you find you need them at a later date. You'll need more later, I promise you

[mariaone]

Many thanks again Gina. I thought that a 25mm pipe would be big enough but having not thought about exactly how many cables i might need to get through it your suggestion of using a 40mm would be a better way to go

[Bizibilder]

Its not the cables but the plugs on the ends of 'em that get stuck if the cable pipe isn't big enough!!! A 40mm hole in a concrete pier wont weaken it to any appreciable extent.

[Gina]

Its not the cables but the plugs on the ends of 'em that get stuck if the cable pipe isn't big enough!!! A 40mm hole in a concrete pier wont weaken it to any appreciable extent.

Quite so!

[nameunknown]

Hi

never hardwire anything so it can't be changed

P

[mariaone]

Ok 40mm it is then. its not just a concrete filled 160mm pipe it is going to be reinforced with rebar and done in one pour so i think the loss of effectively having a 40mm hole down the middle should be ok as it will inside the rebar cage. and if it falls over i'll know how to do it right next time