38 replies to this topic

[Polyphemos]

Hi,

 

Can you reverse the rack so that the pinion engages with the undamaged end ?

 

Doug…..

Interesting suggestion, and probably, but since the damage is more or less in the middle of the rack in this case it’s not going to make a material improvement, but I like your way of thinking!

[eyespy]

Hi,

 

Check my edit in my post #25 regarding a file. That worked for me. 
 

Doug…..

[Polyphemos]

Hi,

 

Check my edit in my post #25 regarding a file. That worked for me. 
 

Doug…..

I’ll have to give that a try.

 

What I’m also considering is somehow mounting it on a cheap achro that I can adjust the tube length on (tube, meet hacksaw) to avoid the need to focus within the damaged area; maybe something like an old Celestron 70mm scope.  The OD of the focuser is about 84mm, the internal thread ID is around 81.7mm, so a scope with a tube somewhere around that might make a good candidate.

[PKDfan]

Hi Lance, call me Jim

The present family of two speed focusers from KUO and some others are very well designed and machined, and when in good shape work extremely well. They’re also relatively simple to work on and adjust.

Where people shoot themselves in the foot when considering whether to work on their own gear is that they lack the correct tools. They’ll use an Imperial size Allen wrench in a metric grub screw, or a Phillips screw driver on a JIS (Japanese Industrial Standard) machine screw, bugger up the hardware, and conclude they lack the skills necessary. Well, I also lack the skills necessary to achieve a desired outcome using the wrong tools.

It’s amazing what a decent set of metric Allen wrenches, metric sockets and wrenches, and a couple of JIS screwdrivers can do to help maintain, repair, and restore Astro gear, and none of those tools need be expensive. I guess what I’m saying is to get some of the right tools and start fiddling. There’s little you can do to harm your focuser and a lot of potential to make it function much better. Plus it can be fun! Good luck!

You read my mind Jim !

I'm looking for those exact same tools now, as you are exactly right, Right tool for the job at hand.

I adjusted it already after about a year of heavy use so its not hard just tedious and a confident hand is steadied by using the correct tool.

I'm actually a bit more trepidacious about fiddling with the Evolux R&P when it comes time for it to be adjusted.

Luckily no changes have been noted after considerable use so seems a R&P is more robust vrs a Crayford ?

That mountain doesn't need to be climbed just yet though so thank the good Graces for that.


Best Wishes !

Lance
CSS

[Polyphemos]

You read my mind Jim !

I'm looking for those exact same tools now, as you are exactly right, Right tool for the job at hand.

….

Best Wishes !

Lance
CSS

Lance, here are some of the tools I have:

 

https://www.amazon.c...ed_asin_title_3

 

https://www.amazon.c...ed_asin_title_2
 

https://www.amazon.c...ed_asin_title_1
 

https://www.amazon.c...ed_asin_title_1

 

Between these roughly 90% of mechanical Astro tasks can be accomplished.

[Yerman]

You forgot to mention the mini lathe.

[PKDfan]

Lance, here are some of the tools I have:

https://www.amazon.c...ed_asin_title_3

https://www.amazon.c...ed_asin_title_2

https://www.amazon.c...ed_asin_title_1

https://www.amazon.c...ed_asin_title_1

Between these roughly 90% of mechanical Astro tasks can be accomplished.

Thank You Jim !

I very much appreciate it !

CSS
Lance
P.s. if your wondering my poor quality allen wrenches got rusted so i'm going to invest quality dollars on the good stuff.

[eyespy]

Hi Jim,

 

Regarding the rack, I had a small nick in a couple of the teeth on an 80mm ED with a similar focuser. By adding a 6mm parfocal ring on the diagonal and another to my most used eyepiece, I was able to ‘miss’ the damaged teeth when focusing. This of course depends upon which side of the damage you need to use for focusing and how much focuser travel you have/need !

 

Doug…..

[Polyphemos]

You forgot to mention the mini lathe.

How could I forget one of my most favorite and useful tools!?!?

 

I’ve used my lathe to make motorcycle and automobile parts and countless other otherwise unobtainable tools and parts for decades. It’s paid for itself multiple times over. The amazing, made in the USA, Sherline Mini-Lathe:

 

https://www.sherline...ge/#description

 

Sherline makes lots of other miniature machine tools:

 

https://www.sherline.com/buy/

 

Of course for fixing a dented fine focuser shaft this will work just as well at a fraction of the cost:

 

https://www.homedepo...GD38B/203656911

 

And let’s not forget the all important abrasive paper holder/pusher tool:

 

https://www.amazon.c...GhlbWF0aWM&th=1

 

Which also comes in handy during lunchtime for Ramen…

[Polyphemos]

Hi Jim,

 

Regarding the rack, I had a small nick in a couple of the teeth on an 80mm ED with a similar focuser. By adding a 6mm parfocal ring on the diagonal and another to my most used eyepiece, I was able to ‘miss’ the damaged teeth when focusing. This of course depends upon which side of the damage you need to use for focusing and how much focuser travel you have/need !

 

Doug…..

Hi Doug,

 

I also use extension tubes to reduce the amount of out travel a focuser requires to achieve focus, so one of those would work the same way. Great suggestion!

 

https://agenaastro.c...sion-tubes.html
 

[GADify]

This is a fabulous thread! Bookmarked. 

 

Thanks for posting! 

[Polyphemos]

Here are several photographs I hadn’t illustrated and I wasn’t able to edit into earlier posts:

 

 

 

[RichA]

Doesn't surprise me that these focusers cost money.  Complex, with a lot of parts.  I wonder how hard it would be to adapt microscope focusing to telescopes?  Reason I wonder is that their 2-stage focusing systems are less complex.

[K-night]

Lance, here are some of the tools I have:

 

https://www.amazon.c...ed_asin_title_3

 

https://www.amazon.c...ed_asin_title_2
 

https://www.amazon.c...ed_asin_title_1
 

https://www.amazon.c...ed_asin_title_1

 

Between these roughly 90% of mechanical Astro tasks can be accomplished.

I have a few things to add.

 

I recommend a No.1 JIS screwdriver.

 

It's good to have right angle hex key wrenches in small sizes when a straight wrench can't access a screw or extra leverage is required. Also, ball-ends are convenient for fast Allen screw removal at acute angles; just don't use a ball-end for breaking a screw free or tightening. I use this 2mm often. However, since this style of hex key is necked down from a larger shaft, it can't reach grub screw F in post #4.