Skywatcher Esprit Focuser

[astro mick]

Hi.

I am considering one of these scopes,but the focuser is putting me off.I would never have another crayford focuser ever,not a patch on a well R/P.

I,m sure the esprit focuser is a lot better but it is still a linear focuser.

Can someone help to put my mind at rest with this thought pattern.

Cheers.

Mick.

[inFINNity Deck]

Hi Mick,

I have an Esprit 150ED, but that came with a R/P focuser. Are you sure that the Esprit you saw comes with a Crayford?

Not that the R/P is without issues. On mine the friction of the planetary gear drive was not sufficient to lift the imaging train when pointing towards zenith and it caused severe slippage when trying to auto-focus.

To overcome this, I replaced the friction type of planetary gear with a 1:16 geared one.

Later I disassembled the original planetary gear, cleaned and regreased it and assembled it again, tightening it more than it was, as a result of which it now does hold even my heaviest eyepiece (Televue Ethos 21mm of 1200gr). Still I do not use the friction gear for imaging, only for visual work.

Nicolàs

[astro mick]

Hi Nicolas.

Yes your right,i should have looked into it further.It seems like there is a linear strip bar at the top,as well as a rack underneath.

Thanks for your reply,as you were the only one who responded.

Better homework next time,befrore i bother the forum.

Cheers.

Mick.

[inFINNity Deck]

You're welcome! I think that not too many members have a 150mm Esprit as it is quite an unwieldy telescope, not very handy in a mobile setup. And with it's long focal length not really a wide field scope 😉

In order to tighten the nut of the planetary gear, you would need a special tool, will send you a picture later, I am currently on the road.

Nicolàs

[Adam J]

23 hours ago, astro mick said:

Hi.

I am considering one of these scopes,but the focuser is putting me off.I would never have another crayford focuser ever,not a patch on a well R/P.

I,m sure the esprit focuser is a lot better but it is still a linear focuser.

Can someone help to put my mind at rest with this thought pattern.

Cheers.

Mick.

I purchased an Esprit 100 last year and it was a very very solid smooth rack and pinion focuser which I will never be swapping out.

Adam

[Stuart1971]

23 hours ago, astro mick said:

Hi.

I am considering one of these scopes,but the focuser is putting me off.I would never have another crayford focuser ever,not a patch on a well R/P.

I,m sure the esprit focuser is a lot better but it is still a linear focuser.

Can someone help to put my mind at rest with this thought pattern.

Cheers.

Mick.

I thought the Espirits come with R&P focusers.... 🤔

[astro mick]

29 minutes ago, Stuart1971 said:

I thought the Espirits come with R&P focusers.... 🤔

They do,but also incorperate a steel linear strip on top i think.

Mick.

[astro mick]

35 minutes ago, Adam J said:

I purchased an Esprit 100 last year and it was a very very solid smooth rack and pinion focuser which I will never be swapping out.

Adam

Thanks Adam.

 

[inFINNity Deck]

As promised, I hereby post an image of the tool I made to loosen and re-tighten the planetary gear. I have placed additional images and explanatory text on my web-site (figures 3, 4, 7 and 8).

Nicolàs

Edited July 28, 2020 by inFINNity Deck

[Sp@ce_d]

Mick you didn't say which one, but just to add. My 2 Esprit 80's have been fine. Never worried about them with the QSI on the back & I have stuck motors on both. I've had to swap focuser's on a few of my other scopes.. with the RC8 it decided for me, split & fell to bits.. dumped it's self on the obsy floor. Luckily I'd already removed the imaging train in time. But yeah, never worried about the quality of the Esprits. Pleasant surprise as I had expected to change it when I got my first one. The 150 is on my wish list if I get around to recommissioning the obsy this year.