finally: my first pier

[yesyes]

Well, not strictly a DIY observatory but I thought it would fit better in this section....

I have been given a 100x100x2400mm (4"x4"x95") timber pole. With this I finally decided to construct a temporary pier for my telescope in my back garden. I can now leave my mount aligned between sessions. This will save me a considerable amount of time setting up my scope and leave me with more observing / imaging time between clouds.

My mission was to construct everything with materials that I already have. No money was to be spent.

This is the finished pier:

I do realise that this pier will eventually start rotting. The timber hasn't been treated at all. The idea was for this to last about 1 year until my girlfriend finally finds a permanent job and we can get a mortgage and buy a house so I can build a proper observatory.

(Any office administrator vacancies in the Maidenhead / Reading / Slough area?? )

More information and pictures on my website here:

yesyes DIY and astro :: Garden Pier

[bamus]

interesting, keep us informed how this wooden pier performs, especially in winter times when during day time temperature will be above 0 and during night time when it drops well below

[spaceboy]

I see the timber stretching and shrinking all over the place but best of luck. If anything it was amazing to see a 10" scope on a CG5

[yesyes]

I see the timber stretching and shrinking all over the place but best of luck.

I think it was worth it (if only for the exercise I got digging the hole ), even if it doesn't last very long. Time will tell. I shall update the thread when it starts twisting / rotting / getting out of alignment. It shall be interesting to see when that will start.

If anything it was amazing to see a 10" scope on a CG5

Funny enough, the 10" is only very slightly heavier than the 8" the mount came with. I guess it's mostly down to the Pyrex mirror. The CG5 seems to have no problems handling that scope.

My greatest worry is the pier adapter breaking while the scope is on the mount....

[spaceboy]

My greatest worry is the pier adapter breaking while the scope is on the mount....

Yeah I don't think I would risk it TBH. Such a nice scope to have crashing into the ground!

[Gina]

Hmmm... big scope on a lightweight mount and even more lightweight "pier".

OTOH I've got (presently) a lightweight 130mm scope on a heavyweight mount on a really solid brute of concrete pier But I'm planning on bigger scopes in the future.

[yesyes]

Hmmm... big scope on a lightweight mount and even more lightweight "pier".

The "pier" is rock solid. I'm actually surprised at just how solid it is. I tried very hard but it would not move a millimetre. The question is for how long...

It's only the piece the mount is sitting on that worries me a little. The wood might be a bit weak because of the rather deep (half way down) circular cut out. And the bolt that is holding the mount is inside that cut out area. I thought about that this evening and I have come up with a way to make it stronger. I'll take a different bolt and attach a steel bracket to the bottom. A bit like a huge washer. This will distribute the tension of the bolt to outside the cut out area. I'll also drill a few holes sideways (horizontally the way it is mounted now) and put some M8 bolts through again with metal brackets on either side. This should prevent the wood from splitting lengthwise.

Besides, when the scope is properly balanced, the only force should be downwards. There shouldn't be any torsion or sheering forces acting on the wood. Or is that wrong?

It certainly is not my proudest DIY project..

[pete_l]

It's only the piece the mount is sitting on that worries me a little.

Yes, attachments made to the endgrain of a block are notoriously weak. I'd tend to go with the "glue and screw", belt'n'braces, approach, with maybe some "L" brackets screwed into the sides and top piece. I like using polyurethane glue (Gorilla glue) for projects like this - the joint frequently ends up stronger than the wood it's gluing. Just don't get it on your skin, it'll stick there for weeks.

Apart from that it looks like a great solution to the question of getting a permanent mount.

[Polar Bear]

Great inexpensive solution and why not use wood !

As a user of lots of wood (I make bass guitars) I am amazed by the strength and resilience of it.

I would however use something like rock maple for the top mounting plate (I may have some off-cuts that would be suitable)

Or send me some sizes or a plan including the cut out and I will knock you something up.

I would also suggest it is glued using a PVA or 'Gorilla Glue' as it is waterproof.

Then just soak everything with teak oil to keep the moisture out (£2.99 B&Q)

I have some plans for making a 10 x 50 right angle finder in wood but that is another story !

Paul

[yesyes]

Thanks a lot, Paul. That would be excellent.

The piece of wood is about 22cm long and 9cm wide. I'll measure it exactly tonight and let you know.

I take it rock maple is a very hard kind of wood?

[Polar Bear]

Thanks a lot, Paul. That would be excellent.

The piece of wood is about 22cm long and 9cm wide. I'll measure it exactly tonight and let you know.

I take it rock maple is a very hard kind of wood?

It is not only tough but has great torsional strength.

Happy to oblige.

Paul

[SlipperySquid]

Very interesting thread A lovely wooden peir project to match the garden surroundings may just be the thing to convert a nagging wife! Teak oil and excotic woods seem to be the way to go

[yesyes]

Indeed... But I have strict orders to find a different cover that blends in better. The blue one is not acceptable, apparently...

[SlipperySquid]

I'm tending to go with the opinion that it would be cheaper in the long run just to get what we want and do away with the wife

As to wives.....it's wierd but as a small child I spent most of my days running away from girls....most my teenage years running after them...and now I'm quickly approaching forty I'm wishing I'd just stopped running altogether

Matt.

[yesyes]

I tend to agree but I think I found one of the good wives (well, partner, we're not yet married). She normally lets me do my stuff as long as it doesn't cost much and it doesn't look too bad. And she appreciates that I have ambitious hobbies rather than watching sports and drinking beer all day.

And no, she did not make me write that..

[yesyes]

It is not only tough but has great torsional strength.

Happy to oblige.

Paul

It's been pouring down here last night, so I didn't want to uncover the pier. Should be better tonight, hopefully.

[Sam]

This is an interesting thread and one I hadn't seen before I used a fencing post for my pier. I don't think there's any issue with using wood if it's strong enough and well footed with dirt rammed in around it - or concrete if you need it. The mount interface is the tricky bit. I found a large block of treated timber for that and have it securely nailed into the top of the post. Well done for having a go!

[AndyH]

Excellent !

I'm a great believer in using what's available.

Andy.

[michael.h.f.wilkinson]

Wood is excellent for a pier. First up, it is very good at damping out vibrations (better than most metal or concrete). I once looked up the tensile strength of regular pine (for an experimental windmill in a school science project), and it was listed as 1.3 tonnes per square cm . A block of 22x9cm has a maximum tensile load of more than 250 tonnes. Torsional loads are typically less, but you do seem to have some margin to play with . The joins between parts are of course usually the weaker link. The only worries might be moisture and warping. The latter can be mitigated by gluing together multiple sections of wood into a single block, in such a way that each section want to warp in a different direction from the others.