Setting up my G11 with RC 10" every night is starting to take its toll on my back. So to shorten the process and make life much easier I have been researching like crazy to get the best pier for the limited views I have.
The Altair Skyshed 8" Observatory Pier is a good design and allows the installer to modify pier levelling and rotation AFTER installation on the base. The price is quite steep but it's a one time investment and I can always move the pier down the track if need be. The design is based on SkyShedPos's own pier which has has similar features.
My question is has anyone purchased the skyshed or Altairastro pier and if so any feedback would be welcome. Furthermore, has anyone made similar custom pier in Sydney or knows any metal works company that could assist me and save money?
Manav same problem here but I am thinking of a portable pier which i can leave outside. I looked at this ages ago but never had time to follow through on it. Now looking at the EQ6 Pier, but unsure if this could be used with a G11 and what modification it might need. I also have limited views and need to move about so a perm pier is not in the near future.
I had the same things, just too much load to bring in/out. I contacted Altair on the same thing, they never replied. In practice sending something weighing ~80~10kg from UK is not ideal cost wise.
I had a local workshop make mine. I did up some drawings with CAD (I can send them to you, solid edge 2D drafting, although I can save as other formats) and had them cost & build, allowing them lots of latitude on parts (although I asked for a max dia pipe) and materials.
End product is great, although over budget by 30%...total cost $980 delivered. But it's a beast, ~ 200kg, way over designed but as solid as they come. Absolutely no ringing. I suspect you can change my design downsize materials and still be well within the deflection specs allowable (> .5 arc sec deflection (caculated), lateral force ~22 newtons).
Bert spoke some good info on piers recently, see here.
Just need to now put in the concrete bas and build a shed around it.
G'Day Yugant,
My pier is 250 mm x 250 mm x 12 mm as a base I use a 100 mm thick wall pipe about 800 to 900 mm high depending how tall you are on top I used 2 x 200 mm x 200 mm x 12 mm one is welded to the pipe the other is bolted to give you fine adjustment on your height on top of that I used pier adapter plate to mount the EQ6 to the top pier plate .
The base holes are 12 mm bolted the concert pad .The top plate welded to the pier and have 10 mm clearance holes the top pier plate has been tapped to 10 mm and I used thread bar to bolt the top plates together by tapping the top plate when you screw the bolts in they will be flush with the top plate.
You can get all of the above from Metaland or Onesteel or you do a drawing and take it to a metal fabrication place and they can do the lot it will be lot cheaper then buying one from overseas
Ian C
I had a local workshop make mine. I did up some drawings with CAD (I can send them to you, solid edge 2D drafting, although I can save as other formats) and had them cost & build, allowing them lots of latitude on parts (although I asked for a max dia pipe) and materials.
Brendan - Can I get your CAD drawings And where did you get the pier to mount adaptor from?
Does anyone know metal fabrication places in Sydney who may be able to build a pier from a plan for a reasonable fee?
G'Day Yugant,
I tried all around and got one from altair for a EQ6 it cost me about $190 all up .I tried a couple of engineering company and it was going to cost about $400 to $500 as it is a one off .
If you find someone in Oz who will do it good luck
Brendan - Can I get your CAD drawings And where did you get the pier to mount adaptor from?
Does anyone know metal fabrication places in Sydney who may be able to build a pier from a plan for a reasonable fee?
Ian and Fahim - Thanks for the info gents!
Hi Yugant
CAD drawings sent. If you want different format or drawings just holler. I included an excel spreadsheet on pipe deflection calculations...just punch in the pipe dia, wall thickness and length and it calculates deflection.
I just went around local fab houses/welding shops/general engineering houses, small ones are probably better. The most difficult thing to source is large diameter pipe and this costs, have a look on the net, scary! These places have contacts and sourced a 2nd hand pier pipe which reduced my costs. I just specified a minimum dia I would accept. They did the rest and got it powder coated and delivered to me.
Powder coating can add cost up to ~$200 ....depends. Again these places have contacts and can get cheaper than walking in from the street.
I made my pier so I fit another top alloy plate and on this fits the Losmandy MA adapter. I can rotate the MA adapter (it has a centre hole for a bolt so it can rotate and many other holes for bolting) for polar alignment. I can thus drill into the plate and tap other holes to lock down the MA adapter if needed. I got my MA from OS but Bintel sell them.
edit:
I should have said...the pier can be a square cross-section as well. Welding shops usually have 225mm RHS and can mig weld 2 together to form a square pier! This would be cheaper than a pipe!
There is a really good thread on IIS about pier design. One of the issues with a lot of manufactured piers is the rat cage that seems to be on top of most. Not so good for a range of reasons but especially flexure. For $750 you could get something built that meets your specific needs.
I had the same things, just too much load to bring in/out. I contacted Altair on the same thing, they never replied. In practice sending something weighing ~80~10kg from UK is not ideal cost wise.
I had a local workshop make mine. I did up some drawings with CAD (I can send them to you, solid edge 2D drafting, although I can save as other formats) and had them cost & build, allowing them lots of latitude on parts (although I asked for a max dia pipe) and materials.
End product is great, although over budget by 30%...total cost $980 delivered. But it's a beast, ~ 200kg, way over designed but as solid as they come. Absolutely no ringing. I suspect you can change my design downsize materials and still be well within the deflection specs allowable (> .5 arc sec deflection (caculated), lateral force ~22 newtons).
Bert spoke some good info on piers recently, see here.
Just need to now put in the concrete bas and build a shed around it.
My G11 has been outside since I got it. Check out the scope and tripod covers from telegizmos 365 range.
I leave everything out there hooked up, cameras, scopes, the lot. Haven't had a single issue.
You'll need the tripod cover as well as a scope cover. My tripod cover never comes off and I leave all my power supplies underneath. They have been bone dry for about the last 8 months. Couldn't be happier with them.
All I need is someone help in giving me an drawing to substitute the concrete part with steel with the 3 screws to match the plate design above and I'm ready to go.
As for top plates, yes pier plates do make nice stuff but they are mainly intended for concrete piers, thus have the colloquial "rats cage" for alt/Az adjustment (thought theirs is nicely made and designed). Even if you have a concrete pier all you need, for the G11, is a round top plate and on top of this a Losmandy MA adaptor that bolts to the plate (can probably even do without top plate).
The MA adapter can thus be rotated for Az for rough adjustment then use micro Az adjusters as required. As for Alt, well as long as you pier top is ~+/-15 degrees or so it doesn't matter as thus can be adjusted out by the mounts latitude or Alt micro adjuster.
Absolutely no need for a set of adjustable pier plates in this situation. Thus my pier has none, just bolt MA adapter on top rotate to suit!
edit:
ahh just got an email.
In reply, pretty much what I said above. If you do a concrete pier just use a top plate of any old metal (bolted to the pier) and on this mount an MA adapter so it bolts thru it's centre to this top plate. No need for precision in Alt/Az for above reasons. Rotate the MA to find SCP then drill/tap some more bolts to hold the MA secure although it's centre bolt should be enough.
Last edited by wasyoungonce; 02-11-2013 at 09:27 AM.
1. Base Plate - 400mm x 400mm x 12mm (Length x Width x Height). The base plate has four concrete anchor bolts 5/8-11 x 12".
2. Tube - 1000mm high with outside diameter 225mm with 9.3mm thickness.
3. Bottom Gussets (four in total) - 750mm high and 150mm from base with 8mm thickness.
4. Top Plate (Pier) - 275mm x 275mm x 12mm (Length x Width x Height). The top plate has four M16 Bolts holes on each side
5. Top Plate (Mount) - 275mm x 275mm x 12mm (Length x Width x Height). The top plate has four M16 Bolt holes on each side as well as holes to fit retrofit the losmandy MA.
I am a boilermaker by trade and have worked in a lot of w/shops here and in NZ , most large w/shops have a lot of scrap pipe an piles of old flanges , of many different sizes just lying around .
Manav's list is a good one his tube is 200mm diameter schedual 80 carbon steel pipe , 150mm sch pipe is 168mm o/d and 100mm sch pipe is 114mm o/d , there are hundreds of off cuts out there if you ask , don't buy new .
A large 12 inch , 150 lb blind flange would make a perfect base about 450 in dia. and its already drilled so that saves labour/costs .
Shop around you might be surprised as over the years I have seen lots of us astronomers given old steel like this for free when the owner/boss discovers its for a telescope .
Brian.
After a frantic start to the year I have finally decided to move the design phase along before the 2014 winter kicks in. I got some measurements done using a ruler. Can someone please confirm that the top plate adaptor which will hold the Losmandy G11 mount has the following specifications:
For the sake of keeping my sanity here is my final design. I intend on purchasing a Losmandy MA adaptor to attach on the top plate and rotating it to get perfect south pole alignment.
Any feedback would be greatly appreciated before I start calling local metal works around the area.
Yep that's the ticket. Square sectioned or angle iron welded together to form Sq section is a good and more likely cheaper option than hunting for large dia pipe.
Ensure you talk to you fab houses and get written estimates and allow them some variations in materials for things like gussets.
I'd try to make the top plate round if you can (although mine isn't) as this allows better ota positioning overhead. Backfilling is probably unnecessary, I had this same hole for mine but found extra dampening is not required.
Also consider bottom plate mount holes bolt at either side close to the gussets as this is the place where the gussets place tension/compression thru the base.
I know it won't help Yugant and a little thread hijacking....I was at Stokes appliance parts Palmerston road Ringwood (Melbourne, just off Heatherdale road) and went past CMA Metal recyclers (same location).
I spied with my keen eye a larger selection of used round tube stock of various big diameters; thicknesses and lengths...perfect for a pier project! Also saw some rollers from conveyor belt systems which may suit as well.
And where did you get the pier to mount adaptor from?
