Trying to put a longer mounting dovetail on my celestron slt 102 refractor, not realizing the screws had nuts on the inside, I removed one screw, leaving the nut adrift in the tube. The tube has supporting gussets inside rendering it too small to put my hand in the focuser end. Can I remove the lens assy by removing the screws that appear to hold it after removing the dew sheild without affecting the collimation or performance of the scope? Celestron doesn't seem to want to comment. Understandable.
refractor disassembly
Started by jackbradley, 12/13/2007 11:25PM
Posted 12/13/2007 11:25PM
Opening Post
Posted 12/14/2007 12:22AM
#1
Try shaking the screw out of the focuser end. Surely collimation will be affected if you remove the objective. If you can't get the screw out of the focuser end, mark the position of the objective cell on the OTA so you can position it back in exactly the same place.
Scott Busby
A.K.A. Reconair
Carpe Noctum
Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the earth.
- Ptolemy,c.150 AD
Posted 12/14/2007 03:48AM
#2
Jack,
It would seem that getting the loose nut out is going to be the eay part. Putting it back in place to fix the old plate or install a new one plate, is going to be tricky part. I have had some success in reaching into tight spaces by taping a nut to the end of a stick pupose made for the task at hand. You could cut a long reach stick out of a sheet of plywood that may put the nut back where you need it. Once the nut is gripped by the screw, the assembly can be tightened until the masking tape looses its grip. You may have to live with a piece of tape inside the tube but it should be out of view.
good luck,
dan
It would seem that getting the loose nut out is going to be the eay part. Putting it back in place to fix the old plate or install a new one plate, is going to be tricky part. I have had some success in reaching into tight spaces by taping a nut to the end of a stick pupose made for the task at hand. You could cut a long reach stick out of a sheet of plywood that may put the nut back where you need it. Once the nut is gripped by the screw, the assembly can be tightened until the masking tape looses its grip. You may have to live with a piece of tape inside the tube but it should be out of view.
good luck,
dan
Posted 12/14/2007 09:54AM
#3
Jack:
A few thoughts:
- Those supporting gussets are probably the baffles that help reduce stray light. They are problem just a tight slip fit so you may be able to slide them out of the tube, first measuring their position.
- A child or someone else may have small enough hands that they can get in and find the nut and reattach it.
- I have never taken the SLT-102 apart but other similar scopes come apart as you suggest, there are three screws that hold the lens cell to the OTA. If you mark the cell so you put it in the same position, you will probably be OK, though caution is the better part of valor...
Some cells are threaded on to the tube which is better but it is unlike that the SLT-102 is like this.
- Whatever you do, do not disassemble the lens cell and remove the elements from the cell.
- Maybe there is a fellow astromarter in your area who would be willing to give a hand with this...
Best wishes
jon
A few thoughts:
- Those supporting gussets are probably the baffles that help reduce stray light. They are problem just a tight slip fit so you may be able to slide them out of the tube, first measuring their position.
- A child or someone else may have small enough hands that they can get in and find the nut and reattach it.
- I have never taken the SLT-102 apart but other similar scopes come apart as you suggest, there are three screws that hold the lens cell to the OTA. If you mark the cell so you put it in the same position, you will probably be OK, though caution is the better part of valor...
Some cells are threaded on to the tube which is better but it is unlike that the SLT-102 is like this.
- Whatever you do, do not disassemble the lens cell and remove the elements from the cell.
- Maybe there is a fellow astromarter in your area who would be willing to give a hand with this...
Best wishes
jon
Funding Member
