Wooden pier advice

[Stevp]

Afternoon all,

I'm toying with the idea of a wooden pier for my setup in the new year (when theres a little less rain!) and was hoping to garner any tips or tricks from people that may have some experience.

Heres my thinking so far,

I've read quite a bit about different materials for piers, wood, concrete, steel, plastic filled with sand. I see the pros and cons with each, but I think wood would suit me best. Dad's in the joinery trade so working it properly is not an issue.

The purpose of the exercise is to reduce setup time, for mainly visual observations. It's only an eq3-2 mount with no tracking. The very most it'll get used other than visual is a few DSLR moon shots, or wide constellation shots, so i'm not concerned (to extremes) with vibration etc.

From what i've read the 'best' way seems to be to laminate/bolt 4 4x4 with grain running in opposing directions also seen some people suggesting that that be covered in ply. Also the suggestion seems to be 2-3 feet cube of concrete.

Can anyone offer any thoughts, or point me at useful info?

Cheers

Stevp

[Bizibilder]

The trouble with wood is that it will vibrate as it is a "springy" material - it is designed to flex and bend in nature to prevent it snapping in the slightest breeze. Steel pipe or concrete are far more rigid and any vibrations are quickly dissapated. I am not saying don't use wood - just be aware that it is not an ideal material foe a telescope pier.

I have made a steel "portable" pier that behaves itself remarkably well with an EQ5 and 120mm refractor on it: http://stargazerslounge.com/topic/122340-a-homemade-freestanding-pier/page__st__40__hl__+pier%20+bizibilder#entry1690728 It is pretty massive and a "lighter" version would, I'm sure, work well with a lighter scope and mount on it.

[nightfisher]

I would second some thing on the lines of Bizi`s steel pier

[Gonzo]

What about something like this one?

http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5527689/page/5/view/collapsed/sb/5/o/all/fpart/all/vc/1

[Stevp]

Thanks Gonzo, thats exactly the sort of thing i'm looking at. I've not seen that page in my searching so far. It's reassuring that people do have success with such a design.

[Stevp]

Thanks for the reading on the steel pier, i've not ruled it out entirely, but it'll probably be a future project when I get a bigger scope/mount.

[JamesF]

Steve Ward has his wooden Enormo-Pier. I think he might just be using it for solar imaging though, so stability over long exposure periods may not be a problem. I'll see if I can find the thread with his pictures.

James

[JamesF]

Took me a while to find the right posts:

http://stargazerslounge.com/topic/166942-sun-in-white-light-3-11-2012-1430/

http://stargazerslounge.com/topic/169219-well-that-should-see-me-through-til-the-solstice/

James

[Stevp]

Wow thanks James, thats great. Now i'm sure that the wooden pier is what i'm after. Mine will be a somewhat more modest height though!

[Enrico]

Wood can be a good material: there are lots of wood types with different properties. Oak is good as it is very stiff, yet doesn't weigh as much as steel/concrete.

Stiff wood also dissipates energy quickly - give a steel tube a clump with a hammer and see how long it keeps making a noise (I.e. vibrating) for! Steel has high mass (high energy strange capability) and a high Q (very willing to resonance cleanly and clears).

Engineered properly I suspect that a wooden pier could be made to be very good indeed, even compared to steel/concrete counterparts.

[Stevp]

The trouble with wood is that it will vibrate as it is a "springy" material - it is designed to flex and bend in nature to prevent it snapping in the slightest breeze. Steel pipe or concrete are far more rigid and any vibrations are quickly dissapated. I am not saying don't use wood - just be aware that it is not an ideal material foe a telescope pier.

I have made a steel "portable" pier that behaves itself remarkably well with an EQ5 and 120mm refractor on it: http://stargazerslounge.com/topic/122340-a-homemade-freestanding-pier/page__st__40__hl__+pier%20+bizibilder#entry1690728 It is pretty massive and a "lighter" version would, I'm sure, work well with a lighter scope and mount on it.

Just had a proper read through your link, thats an awesome project. I am in awe, far beyond my skill set to say the least!

[Stevp]

Thanks Enrico, that's what I'm hoping.

[Zakalwe]

The OP want a simple to construct pier that would allow quick setup, and to take Lunar and widefield shots on occasion. Talking about concrete and steel is completely outside the scope of his/her requirements. And saying that steel "dissapates" vibrations is totally misleading.....steel "rings", wood doesn't.

The OP has no requirement for long exposures as far as I can see, so I think that a simple wooden pier would be a perfect solution. There's only an EQ3 mount going on it, so no need to dig big holes and fill with a tonne of concrete....thats total overkill.

I'd be tempted to get something like a 4"x4" or 6"x6" oak post ( http://www.eoburton.com/oak-beams.html ) and use a simple metal spike to locate it in the ground. Yes it will probably shift a bit over time, and as the beam absorbs/looses moisture, but a simple tweak on the polar alignment on the mount would sort that.

[Gonzo]

The OP want a simple to construct pier that would allow quick setup, and to take Lunar and widefield shots on occasion. Talking about concrete and steel is completely outside the scope of his/her requirements. And saying that steel "dissapates" vibrations is totally misleading.....steel "rings", wood doesn't.

The OP has no requirement for long exposures as far as I can see, so I think that a simple wooden pier would be a perfect solution. There's only an EQ3 mount going on it, so no need to dig big holes and fill with a tonne of concrete....thats total overkill.

I'd be tempted to get something like a 4"x4" or 6"x6" oak post ( http://www.eoburton.com/oak-beams.html ) and use a simple metal spike to locate it in the ground. Yes it will probably shift a bit over time, and as the beam absorbs/looses moisture, but a simple tweak on the polar alignment on the mount would sort that.

this is why I gave this link http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/5527689/page/5/view/collapsed/sb/5/o/all/fpart/all/vc/1 as I believe it's exactly what the OP is after

[Gonzo]

I see another advantage, let's say you're renting a house (hey, not everyone is a house owner...), a wooden pier (nicely built) could be a very good alternative to a concrete one. I don't have to explain the why

[Stevp]

Thanks Zakalwe, that pretty much hits the nail on the head for what i'm thinking.

It seems that oak is coming out as the top suggestion so i'll have a look at that.

[Stevp]

I see another advantage, let's say you're renting a house (hey, not everyone is a house owner...), a wooden pier (nicely built) could be a very good alternative to a concrete one. I don't have to explain the why

Exactly, i found that post (pun intended a little) very helpful. It's at my family home so don't see moving being an issue any time soon, i think by the time i'm finished with the pier it will be repurposed as a very solid bird table

[astrogardener]

You shouldn't have any real problems if the wood is treated against rot and wood worm, make sure any nut's bolts and washers are rust proof and keep a watch for insects that chew (termites, solitary bees..) or peck (woodpeckers..)

A couple of railway sleepers bolted together would be ideal, I think reclamation yards or maybe some garden centers will have them.

Sounds like a good project

[Enrico]

I'm eyeing up a tree stump in the garden at the in-laws as a "visiting pier" for visual use. Currently during the day it serves as the fulcrum for a see-saw, so I know it'll handle a good deal of weight, and doesn't move much.

A little adaptor bolted to the top (with plenty of adjustment in it) and it should be easy to get up and running should we visit when we are not covered in clouds!

[fwm891]

An EQ2-3 doesn't have a very big base so 4 - 4x4's would probably foul the mount as its rotated around to different parts of the sky. A single 4x4 with side vanes to dampen the vibrations like a steel pier would probably be more than enough for visual and wide field camera work.... aka:

With the post base going into a small concrete block - keep it simple

[Patrice Lanteigne]

Hi,

With respect to wood for a pier, I don't know about what is available in your neck of the woods, but here there is 'red' oak and 'white' oak. The white oak is much more resistant to rot and insects. We use it for outdoor and marine projects. Tamarack and White Ash are also very naturally resistant. Lately, torrefied (cooked) structural wood is becoming popular for outdoor applications. It is very weather and insect resistant and does not have the toxic and corrosive properties of chemically treated wood.

[Stevp]

An EQ2-3 doesn't have a very big base so 4 - 4x4's would probably foul the mount as its rotated around to different parts of the sky. A single 4x4 with side vanes to dampen the vibrations like a steel pier would probably be more than enough for visual and wide field camera work.... aka:

With the post base going into a small concrete block - keep it simple

Thanks for that! Your picture is great! I had not considered that design, nor the width of the pier vs the mount width. A very important point. I think I best get the tape measure out.

[Stevp]

Hi,

With respect to wood for a pier, I don't know about what is available in your neck of the woods, but here there is 'red' oak and 'white' oak. The white oak is much more resistant to rot and insects. We use it for outdoor and marine projects. Tamarack and White Ash are also very naturally resistant. Lately, torrefied (cooked) structural wood is becoming popular for outdoor applications. It is very weather and insect resistant and does not have the toxic and corrosive properties of chemically treated wood.

Thanks Patrice, thats really helpful, gives me a few more things to look at!

[Stevp]

Thanks for that! Your picture is great! I had not considered that design, nor the width of the pier vs the mount width. A very important point. I think I best get the tape measure out.

Just had a quick measure. 8x8 is the maximum I'd want to go overall, anything bigger than that would interfere just as you said.

[fwm891]

Just had a quick measure. 8x8 is the maximum I'd want to go overall, anything bigger than that would interfere just as you said.

Is that on-a-side or the diagonal measurement? (ie 8-inch circle)