The
Croydon Astronomical Society
|
Updated |
|
Telescope Replacement Project |
13th January 2008 |
This page documents the replacement of the main telescope at our observatory at Kenley.
The work is now complete and the telescope is operational - weather permitting !
23rd April 2005
The telescope is in place and has been powered up. All we need now are some clear nights to align it !
|
|
|
|
Delivering the telescope |
In position - Dave having a look |
|
|
|
|
Steve trying to hide - the telescope is not big enough ! |
Dave looking at the Radio Mast |
|
|
|
|
Front View |
Dave & Steve looking at the Horizon |
|
|
|
|
Connecting the power |
|
20th April 2005
The wedge mounting plate and the wedge have both been fitted. No pictures as I forgot my camera ! Next operation is to mount the telescope and align it !
16th April 2005
The good news is that the floor joists have been put in place, the new floor cut & laid and we have grouted the bolts in that will hold the telescope wedge. All we have to do now is put the wedge on - level it, install the telescope, connect the power supply & align the telescope. The pictures below show the floor & the pillar with the wedge mounting place in place.
|
|
|
|
|
|
|
|
|
|
South floor & pier |
North floor & pier |
|
|
|
|
Pier & floor from above |
Pier - it really is upright ! |
|
|
|
|
Looking South |
The mounting plate - waiting for the grout to harden |
7th April 2005
The following pictures show the stages in drilling the three holes for the mounting plate. The wooden jig was used to try to ensure the holes went in the correct position - the holes were drilled as 6mm, 10 mm, 12 mm & finally 20mm to give the required 4mm clearance around the studs.
|
|
|
|
Beam used to ensure the jig sat flat on the surface - the rod is a 6mm pin inserted into the first hole to ensure the jig was not moved out of position when the second hole was drilled |
The tension in the beam was such that there were noticeable creaking sounds ! |
|
|
|
|
Two 6mm pins in place and the first 10 / 12 mm hole drilled |
|
|
|
|
|
Drilling the 10mm hole with a guide to ensure the pilot hole was vertical |
The jig still secured by the two 20mm diameter pins used to hold the jig in position while the third hole was drilled. |
|
|
|
|
A view of the jig & pins from above. |
A view of the jig & 20 mm pins from above. |
|
|
|
|
The Jig removed - vacuuming out the dust |
The finished holes from above |
|
|
|
|
The mounting plate resting in place ( the studs have not been grouted in yet) |
The mounting plate from above. |
|
|
|
|
Another view of the mounting plate in situ - note the rust on the join of the top & bottom plates already ! |
Top view of the mounting plate in position. No Sun to check the alignment just plenty of rain ! |
3rd April 2005
Paul & I attended Kenley at Local Noon today & marked the position of the fixing holes using the Sun's shadow when it was due south. These now line up with the old pier. The next stage is to accurately drill these so the three studs can be fixed in with the chemical grout.
|
|
|
|
The pillar & mounting plate looking roughly North |
The pillar & mounting plate |
|
|
|
|
View of the plate from above - south is to the top right |
The Sun's shadow just after noon. The guide lines do not line up with the holes as the holes are not quite aligned with the slot for the RA adjustment ! The plate has been set with the shadow halfway between to allow the same adjustment in both directions |
2nd April 2005
Dave has started work on replacing the floor. Steve & John M tried to align the wedge mounting plate due south using the Sun's shadow. Having done this we discovered that our position for due South is several degrees from where the old pier and thus the Fred Best Telescope was aligned. We are now trying to find out if our position is in error or the Fred Best Telescope polar axis was several degrees of the pole !! These pictures show the new pier with the mounting plate in position .
The next step is to check the alignment using a magnetic compass to check the building and use this to check the pier. In addition we hope to check the alignment at midday on Sunday 3rd April 05 - sun permitting.
|
|
|
|
The New Wedge & it's mounting plate |
The mounting plate temporally positioned on the pier together with the measuring tools |
|
|
|
|
Shadow of the Sun at 15:04 BST when it was bearing 210 degrees. The plate was rotated till the mark which was midway between the holes which are spaced 60 degrees apart. This gives us the 30 degrees to allow for the two hours past culmination |
The aligned plate (and Steve) - not very clear here but the aligned plate is several degrees off alignment with the old pier. |
19th March 2005
The Concrete for the pier has been poured and now needs to be left for 4 weeks to harden & cure before we can drill the three holes for the studding that will fix the wedge to the pier. Meanwhile we can work on replacing the floor. When the holes have been drilled we need to grout the 3 studs in - this will only take a day or so to set and then we can mount the wedge followed by the telescope. Following this we need to test and polar align the telescope.
The next stage is to complete the notes on how to use the telescope and to test this on the first training course. This will probably be trailed on some of the Committee and then we should be ready to run courses to teach the rest of the membership how to use the telescope.
Not related to the telescope project but we also need to refelt the clubhouse room urgently as there have been some leaks that have damaged the board underneath.
12th March 2005:
The Fred Best Telescope has been removed and today we (well Ray mostly) drilled the pier for the reinforcing rods & Dave B, Steve S, Paul H & John M cut the pier former to the correct height and grouted the reinforcing bars into the pier. The former for the new pier has been set in place and cemented in at the base. Next stage is too put some stays up to steady the tube and then pour the concrete. The spreadsheet below shows the amount we have to mix & pour. Meanwhile John M has built the power supply for the new computer. Meanwhile discussions go on as to how to bolt the wedge to the new pier - cast the studding in, grout it in or use 'Rawlbolts' ???? We know we have to get it aligned to true North within about +- 2 degrees - should be no problem for Astronomers - now where is that pole star !!!!
|
|
|
|
The former for the new pier temporally in place |
This is what the wedge will look like when it is finished |
|
|
|
|
Installing the reinforcing bars - the grey material round the rods is the chemical grout - good stuff if rather expensive - only £17.50 for 145 ml ! |
The pier former in place with the reinforcing bar structure inside |
27th February 2005
Still waiting for the detailed plan from the sub-committee but it looks as thought we may be in a position to start work on the new pier on the weekend of the 5th / 6th March 2005 but this is dependant on Ray Bailey getting the pipe to act as the formwork for the pier and also us getting the telescope wedge & mounting kit as well as some vital dimensions of the new telescope so we know how height the pier has to be - it will be approximately 1.3 m estimated from photographs on the Meade web site - there are no dimensioned drawings !!!! As soon as we know the dimensions & shape of the pier we can start drilling the base & grouting the reinforcing bars in.
27th February 2005
The mirrors and other delicate parts of the telescope have been removed and packed for transport. The telescope was prepared for removal on the Sunday 27th February. The lorry is due at Kenley at 08:30 on Friday 4th March 2005 to crane the telescope pot and to take it to it's temporary home on the way to it's new residence it Thailand.
In the meanwhile if you wish to start learning how to use the new telescope a copy of the manufacturers instruction manual for the Meade 14" LX200 is available here (1.4MBytes) {external site}. When you read these remember our telescope will be on a wedge and should already be aligned when you come to use it so you might find the sections on how to operate the hand control & how to use it to locate objects the most useful.
In due course will be producing a set of our own instructions for using the telescope and also having some training sessions followed by a competency test to give you a licence to operate the telescope.
This will be extended to include two further modules covering attaching and using the CCD camera with a second module to cover how to drive the telescope from the computers in the control room when we have got them connected & working.
The next challenge is to motorise the dome !
Here is a PDF file showing the magnification, Field of View & Limiting Magnitude for different eye pieces for our Meade 14" Telescope.
![]()