Hi all. I am new to the forum so please let me know if I have posted in the wrong section.
I've just bought an old Lafayette refractor from a rummage sale, and it's in excellent shape and nearly perfectly complete barring a few minor things I'd like to ask about. I have found threads about and pictures of this same line of scopes on this forum, but could not find some of the more specific info. I would be very grateful for any insight any of you may have! Doubly so if that insight includes where to obtain a manual or other documentation for this scope.
First off: missing parts. This telescope is only missing the locking screw to change between free floating and worm gear adjustment for the declination axis, and the fastener(s) that holds the equatorial mount to the fork on the tripod. The first attached photo clearly shows the missing declination locking fastener and the large threaded hole into which the fastener that holds the mount to the tripod should thread.
Does anyone have insight on sizes or thread pitches for these two missing fasteners? Should I be expecting SAE or Metric fasteners on this telescope? The internal diameter (measured from the peaks of the threads) of that large threaded hole on the equatorial mount head is 13.13mm, or .516 inches. I don't know exactly what that would correspond to in terms of fasteners. Anyone have pointers?
Secondly: cleaning. The gears are all in excellent shape, but all the adjustments feel as though the original lubricant may have dried up. All gear adjustments for focuser, declination and right ascension are very smooth, but not as easily turned as I would expect. Should I dismantle the equatorial head and clean off any old lubricant? If so, what new lubricant should I apply, if anything, on re-assembly?
As for optics, it appears that the objective lenses of both the telescope and finderscope can be removed by unthreading the cowl. Both are quite dusty, and will need cleaning. What type of solution should I use to clean them, and any eyepieces that need a retouch? Will isopropyl suffice?
Thirdly: damage. The cowl that holds the objective lens has a sizeable ding in it. See second attached image. Obviously I will want to remove the lens and set it aside before trying to fix this, but if any of you have dealt with a similar repair, how would you recommend going about it?
Lastly: curiosity. What are these eyepieces, optically speaking? See third image. Does that H stand for Huygens? What is the AH? Are they crummy 2 element EPs? How are the eyepieces/star diagonal/image corrector intended to be retained in the scopes? It looks like these are collared friction mounts with how those holes/slots and that lip along the eyepiece receptacle are placed, but there are no collars to tighten them and secure things. See regrettably poorly angled fourth photo. Are these two more parts I am missing?
Is the solar projection screen that came with the scope as horrendously dangerous as it looks? Should I forget I even have it?
First and foremost, I want to do no harm to this cool antique scope, so I'd rather ask too much than rush ahead rashly and damage something. If desired I can supply more pictures of anything to provide more information.
Once again, any info is greatly appreciated, and thanks for reading!