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  • Writer's pictureBobby Manoo

Restoration of a 1960’s Wooden Telescope

In July 2022, the Flamsteed inbox was greeted with an unusual request from a member of the public. Someone wanted to know if we were interested in taking on a wooden telescope which was built in the 1960’s using military parts from World War II. The owner was just a few miles from where I lived and I decided to go over and have a look – after all, I had never seen a wooden telescope before, especially one with gun parts in it.


I was not aware at the time, but this kit was about to be thrown into the skip because it was not used very much, quite heavy and occupied a lot of space. I made the decision that day to take it, try to restore it and then put it back into use. After spending months on the restoration project, I would like to share this experience and also get your thoughts and suggestions for a new home.


The creator of this kit is an unknown genius who has put in a lot of thought and creativity into this telescope. Given the period in which it was built and the materials used, any restoration would have been challenging, however, I found this project to be both enjoyable and educational at many levels.


Going back to the day when I first saw the scope, the size and height was the first thing that caught my attention. It was already set up in the back garden by the owner and stood over 2 metres tall. The scope itself was square and made of what appeared to be plywood. It was a 6 inch Newtonian Reflector which meant that the eyepiece was at the top end of the tube and most people would require a small ladder to get to the eyepiece for high altitude objects. The wood seemed to have been in good condition although dusty with the inside of the tube filled with cobweb. The rack and pinion were brass and there was also a finder scope fixed onto brass rings.


Photo: First attempt at assembly

The mount appeared to be an equatorial mount with brass dials on the Right Ascension (RA) and Declination (Dec) axis. The counter weight was extremely heavy – perhaps about 6kg. All this was mounted on a solid iron frame which was heavily rusted. Everything was fitted onto wooden tripod legs which seemed to be in good condition. There were also a few dusty wooden boxes which stored accessories, eyepieces and the primary mirror.


History of the Telescope

From available information, the telescope was commissioned in the late 1960’s by Bryan Enfield who was head of English at Tapton House Grammar School near Chesterfield Derbyshire. It was built for his son who had an interest in astronomy. The construction took place at the family home by a technician from the school who had free reign to use all available material. It was his idea to use military equipment and he had inputs from a local astronomer who remains unknown. The Grammar school was closed in 1991.


Bryan’s son used the telescope regularly at the family home and also at the Grammar school in Chesterfield. As he grew older and left for university and travelled to various countries, the telescope remained in the hallway of the family home and was unused for a long period of time.


The entire kit was then gifted to a friend in London who also had an interest in Astronomy. It was used only a few times over many years until it was offered to Flamsteed.


Initial Design with Military Equipment

I was eager to find out about the various parts and mechanisms used in the design of the scope and I sought assistance from two of my neighbours, one is a retired Army officer who was based at Woolwich Arsenal and the other a retired Naval officer. They both help in identifying the various parts and also in suggesting which military equipment, guns or tanks they were taken from.


The main tube is 1150mm long with the sides being 178mm and was made from 9mm Cresta Marine plywood. The attachment for the main mirror and small boxes were made from 6mm Cresta plywood. The main supports, tripod and frame for the telescope were made from Keruing Hardwood Timber. The inner tube was painted with Cuprinol black paint and all outer tube surfaces were treated with Translac interior varnish.


The Finderscope was a 550 mm tube with a diameter of 50mm. This was made from a Paxolin tube consisting of fireproof laminate sheets. These were sometimes used for telescopes and binoculars during this era. The design was similar to the sight-scope used on WWII tanks and this particular tube and the optics were acquired from Charles Frank Ltd of Glasgow. Interestingly, this company provided much of the military optics and lenses which were used during WWII. After the war, the company repurposed many of the optics for use in telescopes and binoculars. Unfortunately, the company folded in 1974.


The RA was made using a Dialsight with a manual clutch from a WWII British Quickfire 25 Pounder Field Gun. The clutch system was housed within two blocks of wood with a small pin to lock the position and a level to release the locks and move the axis.


The Dec axis did not have a clutch system but just used the dials with the degrees marked out and a manual lock on the axis. This was most likely sourced from a WWII Mortar Gun which did not have a clutch mechanism as these were larger and heavier guns.


Both the Axis were assembled on a rather heavy steel mount. This was adapted from the support mechanism which housed the main cannon on a WWII tank. The mount had to be modified to fit the clutch system but it was already fabricated with a 52 degrees angle which is perfect for the altitude setting for south England as this is the latitude that needs to be set for equatorial mounts. It does mean that this is not an adjustable feature and this kit needs to stay at this latitude to be effective.


Photo: Dec Dial with lock on top, bottom dial for RA Dialsight using manual clutch system, assembled on the steel mount

The Rack and Pinion, primary and secondary mirrors were purchased from Broadhurst Clarkson Ltd which is one of the oldest names in amateur astronomy in the UK. This included a 6-inch primary mirror and a secondary mirror with brass housing. There were also three 0.956 inch eyepieces.


Photo: Rack and Pinion

The breakdown of the initial cost during the period 1969 / 1970 was given as the following including any postage and packaging.


  • Mount and Axis                            £38.10

  • Tube and Finderscope               £  3.72

  • Optics                                           £38.58

  • Labour (90 hrs)                            £25.00

  • Total                                             £105.40


The Restoration

I waited until summer 2023 to start the restoration after researching how to treat antique timber, metal, brass and optics. For the wood, I practised on some discarded wooden furniture that I picked up from around the neighbourhood just to ensure that I got it right. Some people actually discard pretty good items which only require basic repairs but we will leave that discussion for another time.


I started by assembling the scope to see how it works and to understand its basic operations. This took some time and effort to figure out how to align the scope and also how to move the RA and Dec dials. I did not initially understand how to lock the RA into position, there were levers next to the dial but they did not seem to do anything. I thought something may have been broken inside the gears but then I saw a small pin about 3mm in diameter and just over 3 cm long. It was just sitting on the base of one of the dials. I have no idea how this had not fallen off during all the movement and transportation. This was the missing piece because this pin was used to lock the axis in place and also engaged the levers that previously did nothing. I could not use the scope for observing because the primary mirror was covered in layers of dust and the secondary mirror had spider webs all over it. There was no chance of collimation in that condition. Nonetheless, having understood the basic movements, it was now time to take it apart.


I started with all the metal parts and the plan was to give them a thorough clean, apply a rust treatment and then paint all the surfaces. Taking apart the pieces was a fairly simple process; the most challenging aspect was finding spanners to fit the many different sizes of bolts which were used. In some cases, if there were two bolts on one item, the bolts were of different sizes. This is a classic indication of a DIY project where various pieces were put together in the assembly.


Photo: RA Clutch Assembly being disassembled

There were also a lot of small brass pieces, the rack and pinion, the dials on the RA and Dec and the secondary mirror housing to name a few. I bought 3 different cleaning liquids and polishes which I found online and tried each to see which gave the best results. I was doing this under the watchful eye of my mother who was visiting at the time and took an interest in the project. She was not impressed by the results of any of the liquid polishes and literally cast aside my online purchases and opted to use her home-made methods. I was not convinced that lime and baking soda would work better than my polishes but I was made to swallow my pride and concede defeat. My mother took care of all the brass pieces by leaving them overnight in a solution of freshly squeezed lime juice and baking soda, then cleaning up with a toothbrush and wire wool where necessary. The final cleaning was with mild dishwashing liquid – and the shine came through brilliantly.


Photo: Brass pieces being cleaned

The steel and iron parts were all cleaned with soap and water and then treated with two coats of a rust remover and rust barrier. Once dried, I applied two coats of metal paint to complete the job, some surfaces were spray painted and others were hand painted. I decided to go with an all-black matt look for the metal as this contrasted really nice against the brass pieces and the wood. The counterweight was locked by one locking bolt and ideally required another backup in the event of failure, I put in an additional T-handle lock pin with a quick release mechanism for added protection.


Photo: Metal parts being treated and painted

The next section for attention was all the wooden parts. The grains on the different types of wood were different and were covered with stain and varnish which were not in the best of condition. The surface had to be stripped back to the bare wood, sanded and treated. I started with a paint stripper to remove all the old varnish and stain. This worked fine but it required a lot of manual effort in terms of scraping, sanding and cleaning the surface back to the original wood, as well as filling holes and repairing cracks. I then applied a teak coloured stain followed by teak oil and finally a layer of beeswax polish. This should provide ample protection from moisture, dew and also withstand cold and freezing temperatures. The colour differences in the wood was not immediately noticeable so I was overall happy with the results. The top surface of the tripod had two glass spirit levels embedded into the wood and one of these was broken. I carefully removed both of them, cleaned the housing and bought new plastic covered levels and installed them within the same housing.


Photo: Wood being stripped and resurfaced


The restoration on the optics was the final phase, the primary mirror was enclosed in a handmade wooden enclosure which utilised 3 large screws to adjust the angles. The ends of the screws pushed against the back of the mirror and this was not ideal. I put in a layer of thick cardboard to protect the ends of the screws from damaging the mirror and also changed the screws. The mirror itself was cleaned with a solution containing 50% ethanol and 50% distilled water. The secondary mirror had a small chip but was usable. The housing was made of brass and the three adjustable screws were in good condition.


The finderscope required a somewhat significant overhaul. The original design required the user to position the eye quite close to the body of the tube at an awkward angle. It would be better if there was a 45 degrees eyepiece which would make this much more comfortable to use. I had an old finderscope which had the correct dimensions to be fitted to the original tube. All the original housing and endpieces were retained but I had to make a bespoke fitting for the eyepiece using PCV pipes and cardboard rolls. This meant that the Charles Frank lens which was previously used as the eyepiece had to be removed and put out of service.


The rack and pinion were reasonably ok and I left it as it is rather than replace it. However, the system was built for 0.956-inch eyepieces which are not widely used today. This limited the range of eyepieces that could be used and the three eyepieces which came with the telescope were very limited in magnification and did not fit the housing very well. I bought an adapter which would use 1.25 inch eyepieces and also got a set of eyepieces with a wider range of magnification. This simple upgrade opened up the possibility of using a wide range of equipment, including 1.25 inch CCD cameras, DSLR cameras, filter wheels and a host of other adapters.


Photo: Mirrors cleaned and shiny again

Putting it together

Pulling all the pieces together is perhaps the best part of a project like this. All the parts were cleaned, painted, oiled and ready for assembly. The RA and Dec assembly were put together first and then attached to the main tube. The upgrades to the finderscope were then done and attached to the main tube using the original brass holders. Once this was up then the rack and pinion as well as the attachments for the eyepieces were assembled into place. During the assembly process, I replaced old screws with new hex socket capped screws which made releases a lot easier. The entire kit was then mounted and ready for testing.


Photo: New look RA and Dec dials

Photo: Full assembly


A quick collimation was done during the day and the finderscope aligned. The new position of the eyepiece on the finderscope worked well and all was set for night of stargazing. The first time I looked at the Moon through the telescope was just astonishing, not only was the optics really good, but the entire mechanism of the telescope really worked. The RA manual clutch was easy to handle and moving the Dec in place was also quite easy. The eyepiece upgrade also worked well and allowed me to attach my DSLR and take some photos, perhaps the first time this scope was being used for astrophotography. I then turned the scope to Jupiter which was high in the night sky at the time, I was able to see good details on the planet including the bands and the 4 largest moons were also clearly visible and sharp.


Photo: Unprocessed images taken of the Moon and Jupiter


Future Work

There are some ‘nice to have’ work that could still be done as improvements but would require a higher level of skill set - but are not really essential in order to use the scope. As it stands, I am quite happy with the outcome and the restoration that was done. The cost for restoration is as follows:

  • Mount and Axis                          £112.46

  • Tube and Finderscope             £75.80

  • Optics                                          £ 9.99

  • Total                                             £198.25


This has been a very enjoyable and rewarding experience. It has taken my DIY skills to new levels and have learnt a great deal about WWII artefacts. Before this project, I had no idea how a Field Gun or Mortar Gun worked and did not even know they used Dial Sights or sophisticated optics. Most of all, I was in awe at the level of creativity that went into the design of the kit and how it was assembled from so many varied parts. I loved the fact that the designers took military equipment to build this telescope to ignite the imagination and curiosity of those young minds emerging from a world war. My hope is that this telescope can be continued to be in use and kept in good condition for years to come. I know it will not measure up to the modern telescopes with fancy gadgets and automated instruments but this scope has history, character and a story that can be combined with a stargazing experience unlike anything that can be found today.


A short video on the restoration process can be found here:



 

If you have any ideas for a suitable home for this kit, then please email your suggestions to flamsteed@rmg.co.uk

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