DIY half-pier?

Wanna make a scope? Or better still, grind a mirror yourself. Or, you have some good tips in making a really useful accessory? This is the place to show what your hands can do...
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kingkong
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DIY half-pier?

Post by kingkong »

looking at building a half pier.

have some ideas on how to do it.... but just wonder if one of you good fellows have drawings or photos (esp of the connection points) of your vixen-or-equivalent half pier that you are willing to share with me for reference.

i'll share my results here if the project is a success, either in shop drawings that others can bring to workshops in sg or jb for fab, or may be even in the form of finished products shipped from where i am (or thailand or indon if other have connections) at a potentially significant cost saving compared to new one bought from the states.

thank you for considering. :wink:
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MooEy
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Post by MooEy »

i'm oso interested in getting one. buying one of those original cost like us$150 >.<

as far as i know, the half pillar is separate into 3 pieces.

the top piece is just like the top part of the legs, one knob below to screw in to the head and one metal protuding out for u to do polar alignment. it has 3 holes, which are also tapped, to hold on to the center tube.

the middle part is just a piece of 4" tube, with 6 holes in it. 3 to hold to bottom, 3 to hold to top.

the bottom part is a little challenging. it looks more like the bottom part of ur mount head. i'm not exactly sure if it needs the azimuth adjustment part. might need to further explore.

what i am more interested is maybe something that looks like the sphinx half pillar, more of a 1 piece design. not sure if anyone has any idea how to make one.

~MooEy~
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kingkong
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Post by kingkong »

MooEy wrote:as far as i know, the half pillar is separate into 3 pieces.
the top piece is just like the top part of the legs, one knob below to screw in to the head and one metal protuding out for u to do polar alignment. it has 3 holes, which are also tapped, to hold on to the center tube.
the middle part is just a piece of 4" tube, with 6 holes in it. 3 to hold to bottom, 3 to hold to top.
the bottom part is a little challenging. it looks more like the bottom part of ur mount head. i'm not exactly sure if it needs the azimuth adjustment part. might need to further explore.
what i am more interested is maybe something that looks like the sphinx half pillar, more of a 1 piece design. not sure if anyone has any idea how to make one.
hi Moo, thanks for your inputs. Any chance you can get hold of some photos of a half pier?

my current designs include both 1 & 2 pieces:
2-pieces - top bracket to screw onto the mount like your previous description but the tube and bottom bracket can be one piece. the az adjusment is on the top bracket, it can be easily achieved with a bolt through the top plate. the bottom plate just need a hole for the protrusion to stick through.
actually the 2 and 3 pieces design are identical, but the 2 pieces should be stronger and since there's really no advantage in having a detachable bottom piece. or is there?

a one-piece design will require a threaded rod that goes all the way from the bottom through the extension, into the mount.

before i finalise my design and send to fab shop for a quote, i'll do a prototype using the all-useful--for-astro-diy PVC pipes & fittings. i've been playing a little PVC lego last weekend with various pieces and done some modifications on them to see what works and what doesn't work. i think i've finally nailed down something that looks promising. once it's done up, i am sure the pvc extension pier will be at least good enough for visual use. i will share the final prototype design c/w photos here once i've got it to work. it will be very cheap. will require some DIY cutting and drilling, if you have the tools.

how tall is the typical half pier? i'm making mine at least 110mm because that's the height of the suitable PVC fitting and it will just let the shaft clear the tripod leg with the weights that came with my SN8. might have problems when i add camera and/or guidescope later....
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weixing
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Post by weixing »

Hi,
The new half-pier for the Sphinx mount is a better design than the old vixen half-pier. It is easier to install and use than the old version. Below is the picture of the half-pier that I found in the web.

Hope it help and have a nice day.
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Yang Weixing
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MooEy
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Post by MooEy »

as much as i like the sphinx half pillar design, i don't think anyone would be able to make one cheaply. i did see a half pillar at sp, one that is paint-less. maybe someone like remus would have idea on how to make one.

~MooEy~
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kingkong
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Post by kingkong »

ha WeiXing, thanks for the pic.

that's exactly the one piece half pier i dreamt about few days back - one that doesn't require a long, through, threaded rod. i'll definitely ask the shop how expensive it'll be to cut the tube like that. but i figured earlier, that it'll be cheaper to just use a long threaded rod....

i'm surprised the pier has a flat bottom... :?:

also.... why does one need the az adjustment at the bottom?

how high is the half pier?
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weixing
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Post by weixing »

Hi,
that's exactly the one piece half pier i dreamt about few days back - one that doesn't require a long, through, threaded rod. i'll definitely ask the shop how expensive it'll be to cut the tube like that. but i figured earlier, that it'll be cheaper to just use a long threaded rod....
All half-pier that I come across don't have a long, through, threaded rod... all of them use a hollow metal tube.
i'm surprised the pier has a flat bottom...
I wonder why you are surprise that the half-pier has a flat bottom??
also.... why does one need the az adjustment at the bottom?
That is for accurate polar alignment. You don't want to adjust the whole tripod when your mount is slightly point away from the north, right? So the az adjustment is use to adjust the mount head to point accurately at the north.
how high is the half pier?
The half-pier is around 9" tall.

Hope the infomation help and have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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MooEy
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Post by MooEy »

"That is for accurate polar alignment. You don't want to adjust the whole tripod when your mount is slightly point away from the north, right? So the az adjustment is use to adjust the mount head to point accurately at the north. "

dun think u need 2 az adjustment to do polar alignment. the mount head itself have a set of az adjustment already.

i think the main reason for the set of az adjustment below is that no matter how u tighten the screw below the mount head, the mount head still can move left and right. the set of az adjustment stops the pier from turning left and right. then u do ur polar alignment from the mount head's az adjustment.

my main question now, how did vixen make the sx half pillar one piece. did they solder all the parts together, or cut the half pillar out of something else.

~MooEy~
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weixing
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Post by weixing »

Hi,
dun think u need 2 az adjustment to do polar alignment. the mount head itself have a set of az adjustment already.
Ha Ha Ha... forget that this is a half-pier... :oops: Anyway, the two screw is to secure the north pad on the tripod, so that the half-pier can properly secure on the tripod.
my main question now, how did vixen make the sx half pillar one piece. did they solder all the parts together, or cut the half pillar out of something else.
I think most likely they use a mold to make the half-pier and cut the slot out.

Have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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kingkong
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poor man's half-pier prototype 1.01

Post by kingkong »

OK. Here's Kong's Poor Man Half-Pier 1.01 :D
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