sanath
August 18th, 2017, 09:38 PM
Hi all,
I recently started a project to modify an existing Meade 16" Lightbridge to a portable version so that it can be transported in a small vehicle or for air cargo, i used design ideas mainly from http://www.reinervogel.net and also from http://www.roelblog.nl/2012/11/bouwverslag-406mm-f4-5-truss-dobson/ and would like to thank Reiner Vogel and Roel Weijenberg for sharing their ideas.
Design Constraints and some rules i followed
1) mod must be performed with nondestructive methods of the lightbridge parts.
2) parts from the older design can be used in the new one without altering it
3) reusability to reduce the project cost
4) portability should be achieved so the telescope can be transported for atleast domestic air travel
Workflow :
Day1-4: i used this time to plan out how and what alli must reuse from the older design and hence what new i will have to design from ground up.
Day 4-7: Aquiring raw materials like aluminium shafts , hollow pipes and a slab of alumium
Day7-15: Machining of aluminium mirror cell and truss pole ends and buying plywood sheets ,veneer sheet.
Day16-18: Wood working for mirror box
Day18-25: Assembling the OTA and checking for focus
Day25-30: Making of rocker,ground board and Alt bearings
Expenses: ( INR is indian rupees)
Metal Milling /Lathe work: 6800INR= 106USD
Plywood=18534INR= 289USD
Carpenter=3000INR= 47USD
Aluminium and casting=5150INR= 80USD
CNC wood work=2100INR= 33USD
Hardware, tools and misc: 5084INR= 79USD
total = 634USD
About the mod:
i redesigned the mirror cell partially and used the mirror cell assembly from the lightbridge, i also reused the upper and lower truss holding rings and clamps,secondary cage and az bearings (lazy susan).
i then had to redesign the new truss tubes based on some simple calculations and the rest of the calculations were from Reiner Vogels website, i had to modify some for my requirements.
finally here are the pics :
https://drive.google.com/drive/folders/0B1Q9Qcz4nCaXRTRwTW9fbllESzQ?usp=sharing
http://imgur.com/a/pvjiU
Problems yet to be solved:
Friction in alt bearings, as i dont have access to ebony star or similar material in small quantity.
comments and advice welcome. :D
I recently started a project to modify an existing Meade 16" Lightbridge to a portable version so that it can be transported in a small vehicle or for air cargo, i used design ideas mainly from http://www.reinervogel.net and also from http://www.roelblog.nl/2012/11/bouwverslag-406mm-f4-5-truss-dobson/ and would like to thank Reiner Vogel and Roel Weijenberg for sharing their ideas.
Design Constraints and some rules i followed
1) mod must be performed with nondestructive methods of the lightbridge parts.
2) parts from the older design can be used in the new one without altering it
3) reusability to reduce the project cost
4) portability should be achieved so the telescope can be transported for atleast domestic air travel
Workflow :
Day1-4: i used this time to plan out how and what alli must reuse from the older design and hence what new i will have to design from ground up.
Day 4-7: Aquiring raw materials like aluminium shafts , hollow pipes and a slab of alumium
Day7-15: Machining of aluminium mirror cell and truss pole ends and buying plywood sheets ,veneer sheet.
Day16-18: Wood working for mirror box
Day18-25: Assembling the OTA and checking for focus
Day25-30: Making of rocker,ground board and Alt bearings
Expenses: ( INR is indian rupees)
Metal Milling /Lathe work: 6800INR= 106USD
Plywood=18534INR= 289USD
Carpenter=3000INR= 47USD
Aluminium and casting=5150INR= 80USD
CNC wood work=2100INR= 33USD
Hardware, tools and misc: 5084INR= 79USD
total = 634USD
About the mod:
i redesigned the mirror cell partially and used the mirror cell assembly from the lightbridge, i also reused the upper and lower truss holding rings and clamps,secondary cage and az bearings (lazy susan).
i then had to redesign the new truss tubes based on some simple calculations and the rest of the calculations were from Reiner Vogels website, i had to modify some for my requirements.
finally here are the pics :
https://drive.google.com/drive/folders/0B1Q9Qcz4nCaXRTRwTW9fbllESzQ?usp=sharing
http://imgur.com/a/pvjiU
Problems yet to be solved:
Friction in alt bearings, as i dont have access to ebony star or similar material in small quantity.
comments and advice welcome. :D