Author Topic: Finder scope with crayford focusser  (Read 588 times)

savarin

Finder scope with crayford focusser
« on: August 13, 2018, 09:45:41 AM »
Whilst agonising over what to do for my binocular I had to fix a broken finder scope for a mate.
First off I started with these

that I made into a bunch of these, Z means zinc alloy, no markings means aluminium.


First off I faced bother ends, then squared off 2 sides so I could drill a 4mm hole through. Then I mounted it in the 4 jaw off centre and only using 3 of the jaws bored it out for the eyepiece tube. To say I was apprehensive here is a bit of an understatement but nice and steady did the job with no problems.


This was then mounted between two mandrels so I could reduce the rear side to fit onto the mounting base.

That brought it down to this size. The right angle section has 4x10mm stainless bearings fixed on and three x M4 tapped fixing holes. The c/sunk screws will be changed out for flat heads when they arrive.

The base plate was turned from a small chunk of 10mm plate
and assembled like so.


The 4mm stainless shaft uses pressure/friction alone to move the focusser tube in and out which rides on the four small bearings.

all assembled with a knurled knob on each side. The scratched tube is nothing to do with me  ::)





chips and more

Re: Finder scope with crayford focusser
« Reply #1 on: August 13, 2018, 04:59:09 PM »
Excellent!

4GSR

Re: Finder scope with crayford focusser
« Reply #2 on: August 13, 2018, 08:51:52 PM »
Your innovative ways of doing things and coming up with simple instrumental ways just down right amazes me.  I need to hire you to help me with some design projects I'm dealing with.

Thanks for sharing and keep the post cards coming!

Ken
Ken

Carpenter84

Re: Finder scope with crayford focusser
« Reply #3 on: August 13, 2018, 10:28:04 PM »
No kidding... to take a bunch of hard drive cases, that are likely available dime a dozen, and make a pile of raw material is the epitome of reaourceful.
Shawn

First 9x42 column mill,
Enterprise 10x28 lathe,
Ko Lee 6x12 surface grinder,
Airco dip/stick 160 welder,
Fully stocked wood shop.

grumpygator

Re: Finder scope with crayford focusser
« Reply #4 on: August 13, 2018, 10:47:46 PM »
Solid as allways C.
You way of looking at a project and getting it done with what you have on hand is inspiring to say the least.
My Brother from down under keep them coming.
 And my personal thanks for sticking with us during the site crash. Your work on these projects made me take out an old telascope I got with ciggerette coupons and watching the sky again.
Carry On Mate.
   **G**

savarin

Re: Finder scope with crayford focusser
« Reply #5 on: August 14, 2018, 05:13:04 AM »
thanks guys, much appreciated.