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DIY tripod questions

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#1 ASTERON

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Posted 29 January 2013 - 01:37 AM

Hi,
I want to build a heavy duty tripod for carrying a DM6 mount and a 40-45 Lbs of OTA.
Since this is my first DIY attempt I need your help on some questions
1. taking into account that I live in Israel, what is the best type of wood to make the legs? I cannot get exotic wood types at a reasonable price.
2. Are there any sources of information on tripod mechanical design ?
3. I intend to make the tripod head from an aluminum plate. Do you have any ideas about tripod head design, in particular about how the legs should be connected to the head plate.
I have no access to special tools, so all work will have to be done with a drill and jigsaw.
Thanks for your help

#2 furrysocks

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Posted 29 January 2013 - 02:37 AM

Take a look at this one made from ply... http://stargazerslou...ount-and-scope/

#3 don clement

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Posted 29 January 2013 - 03:05 AM

This six member tripod worked really well for me.
http://tinyurl.com/azqod3d

A good reference for making a tripod can be found in "Structural Considerations for Telescope Makers," by John Brooks, in the June, 1976, Gleanings for ATM's in Sky & Telescope (pages 423-428).

Don Clement

#4 ASTERON

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Posted 29 January 2013 - 01:44 PM

Hi Furrysocks,
Thanks for the link - the tripod looks great and also easy to make. I guess all the wood cuts are glued together ? Did you use dowels for strength and alingnment ?
Originally what I had in mind was a folding one for compactness and easy carrying. However, I like your concept si I might try to improvise on it if I decide to go this way.
Thanks for the idea :bow:

#5 Meep_Esq

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Posted 29 January 2013 - 01:47 PM

This is a great example @asteron - in both cases the legs are made of triangles, which is naturally more rigid that legs that are a single "pole". I attached my tripod legs thus:

Posted Image

using right-angle section to make the connection between the legs at the tripod head, but with a bit of tinkering I am sure there are many ways you could do this. I used aluminium section to make my tripod legs, but I can't see why any straight, local (inexpenive) wood, once it has been painted/sealed would not do the trick. Look forward to seeing pics of your project. :-)

#6 ASTERON

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Posted 29 January 2013 - 01:53 PM

Hello Don,
Great looking tripod and design.
I particularly like the six-pole cross bacing design.
I have actually seen here people do some heavy duty wood tripodes that had a triangular design looking in cross-sectional view like a squashed "H" form - I guess this is quite a strong structure because it cannot twist.
Do you have anu sketches pof the aluminum tripod head-plate ?
Also I would be thankful if you can e-mail me a scanned copy of the ATM article you mentioned. If you have a copy I will PM you my E-mail.
I will try to google for a copy but I am not sure I can find one.
I want to be real methodical about the design.

Thanks
Lihu

#7 ASTERON

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Posted 29 January 2013 - 01:57 PM

Hi Vaughn,
Thanks for the tips. Do you have a photo of the other end of the legs ? I am interested to see how you joined the ends of the triangular legs.
Thank you

#8 don clement

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Posted 29 January 2013 - 02:21 PM

Hello Don,

Also I would be thankful if you can e-mail me a scanned copy of the ATM article you mentioned. If you have a copy I will PM you my E-mail.
real methodical about the design.

Thanks
Lihu


Contact Sky & Telescope as they own the copyright.

Don

#9 ASTERON

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Posted 29 January 2013 - 02:59 PM

OK
Thanks
Lihu

#10 StarStuff1

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Posted 29 January 2013 - 04:06 PM

A solid leg tripod is not necessarily stronger/sturdier than a tripod leg made with two pieces of wood in compression. A tripod whose legs do not fold is normally stronger than one who does. It becomes a "tripod stand" when locked together as a solid unit. At least this is the name used by Sam Brown in the book "All About Telescopes"

A few years ago I tried to combine the two concepts and came up with this. The tripod tray has lugs glued and screwed to it. A metal T-nut is inserted from the back. When the hand knob is pushed through a wood piece that can slightly pivot the unit locks up tight as a tick. Normally I leave it in the locked position for home use but of course it can be slightly dissasembled so the legs fold up for transport.

Most any good, strong wood can be used for a tripod. I usually use red oak as it is commonly available. But other woods such as ash work great. Soft, grainy woods can cause problems. I'm not sure what woods are available and at what cost in Israel.

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#11 furrysocks

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Posted 29 January 2013 - 04:21 PM

Hi Furrysocks,
Thanks for the link - the tripod looks great and also easy to make. I guess all the wood cuts are glued together ? Did you use dowels for strength and alingnment ?
Originally what I had in mind was a folding one for compactness and easy carrying. However, I like your concept si I might try to improvise on it if I decide to go this way.
Thanks for the idea :bow:

Not my design, I'm afraid. I haven't built one and probably won't, but what struck me was the economic use of a commonly available material to generate something with such inherent stability. Albeit not particularly portable.

#12 ed_turco

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Posted 30 January 2013 - 02:18 PM

I coulda sworn that I posted a picture of my crutch tripod here -- total cost 5 dollars and holds 200 lbs with ease.

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#13 tim53

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Posted 30 January 2013 - 04:38 PM

ed, that's lame! :shocked: :grin: :tonofbricks:

#14 rboe

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Posted 30 January 2013 - 04:44 PM

Built up legs; regular construction 2x4 wood with plywood skins (thin skins; thin as in door skins) can be very light and strong. Like hollow core interior doors. You will need solid wood where you have attachement points but that's it.

Just need to be glued, no fastners (staples or small brads to hold things while the glue sets is all if you don't have clamps).

You can take hints from the wood strip canoe (typically called cedar strip canoes) where wood strips are glued up then coated with fibreglass fabric and epoxy.

You can have some fun with this!

#15 kfiscus

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Posted 31 January 2013 - 01:50 AM

I'd highly recommend using Baltic Birch plywood. Here in the US, it comes in sizes like 3/8", 1/2", and 3/4" and is sold in 60"x60" sheets. I have no idea of other name(s) or metric dimensions it may have. It is not cheap, but is worth it's price. I pay $55 for a sheet of the 3/4" stuff.

#16 Thomas Karpf

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Posted 31 January 2013 - 09:41 AM

I coulda sworn that I posted a picture of my crutch tripod here -- total cost 5 dollars and holds 200 lbs with ease.


Thanks for reminding me. I've had aluminum crutches lying around for years that I got for just such a project; I should start on it.






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