Made a quick sight-tube today for the 12.5"
Part's: 2" exhaust tubing....1 skim off in the lathe for a snug fit in the 2" focuser.
1 cardboard disk with a 2mm hole in the centre....masking tape to hold it on.
cost: 10 buck's labor for the lathe work/2 buck's for the pipe.
Work's a TREAT!!!!
(How far was my secondary out? Not much!
)