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ES ED 102 focuser options?

Explore Scientific ED102 Essential Series Air-Spaced Triplet APO Refractor (ES-ED10207-02) ZWO EAF Focuser Troubleshooting Help Needed
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Sean Mc avatar
Sean Mc avatar
Heya. I messed up the brass pinion on my ES ED 102 while putting the ZWO EAF on it. It was in the winter, and I didn’t make sure the pinion and rack were meshed properly when I torqued it down. The pinion teeth(?) are now messed up and the focuser is pretty rough without the EAF. The rack seems fine. With the EAF, it has trouble getting good focus. I can’t find a replacement focuser anywhere online, and ES doesn’t seem to have replacement parts or focusers. 

Does anyone have any suggestions for a replacement focuser that doesn’t involve huge expense or wait times?

Thx in advance!
Jim Raskett avatar
Jim Raskett avatar
Just an idea, but have you contacted ES directly?
I had a few issues with my ED102 many years ago and they were very helpful.
Worth a try.

Good luck!


Jim
Well Written Respectful Concise
Sean Mc avatar
Sean Mc avatar
Yessir i did. What a painful experience. They apparently don’t have parts (as i just need the pinion) and don’t seem to have replacement focusers either. The rep I’m dealing with told me to contact retailers… nice. Nobody has stock for this older scope. Now she’s set up an return where I would send my entire scope back and they would give me “up to $400” on the cost of a new scope. 

that’s not a reasonable solution to me.
Jim Raskett avatar
Jim Raskett avatar
Yessir i did. What a painful experience. They apparently don’t have parts (as i just need the pinion) and don’t seem to have replacement focusers either. The rep I’m dealing with told me to contact retailers… nice. Nobody has stock for this older scope. Now she’s set up an return where I would send my entire scope back and they would give me “up to $400” on the cost of a new scope. 

that’s not a reasonable solution to me.

That is absolutely ridiculous! Very sad to hear that.
I guess that a replacement focuser is the only way. Hopefully someone will come along with a suggestion.
Jim Raskett avatar
Jim Raskett avatar
I just did a Google search and found this on Adorama if it helps.  
I assumed that you have the Essential Series scope with the 2” focuser like I do. 


Sean Mc avatar
Sean Mc avatar
“Special order” unfortunately.
Jim Raskett avatar
Jim Raskett avatar
I see that there are other (like GSO) Crayford focusers out there that might fit the ED102.
Are the ES folks helpful at all? Can they maybe give you some alternatives or tube measurements so that you can find an aftermarket focuser?
I’d try beating on their door some. There should be someone there that can help you. 
I know personally though, customer service has gone out the window for lots of companies nowadays. 

Jim
Helpful Supportive
Christian Zappel avatar
Christian Zappel avatar
I have a " EXPLORE SCIENTIFIC ED APO 102mm f/7 FCD-1 Alu 2" R&P Fokussierer" since several years and never any problems with. Even so I am selling this scope, because I have too many, it was always a very trsutable and nice working horse. The original focuser is still fine and I alwyas have used the ZWO EAF.

Even so, some people don´t like the original focuser and change it to any other focuser...there is a plenty of choice. I recommend you contact a well known astro shop and ask for advice, installment  and for a good service. If you check the website from TSeleskop-Express, you will find several choice of focuser for replacement:
https://www.teleskop-express.de/shop/index.php/language/en/cat/c92_Okularauszuege---Mikrountersetzung.html

As I mentioned before, I highly recommand to ask an astro shop reasonable accessable from your home and let them install the new focuser you have chosen.

Wish you all the best
Christian
Supportive
Jeff Sutherland avatar
Jeff Sutherland avatar
Not sure that it will be without huge cost, but you could always get a threaded adapter to the threads of a focuser of your choice...

I went through the process of finding the tube threads for my ES ED102, and after being told by ES that they couldn't get the info, I managed to get the thread spec from Ron at moonlite. Here is his response:
Hi Jeff,

  I list that flange size on our web page as ------

The ES102 Essentials flange fits the Explorer Scientific 102 Essentials.
It is a male 3.884" X 1mm threaded flange. The correct drawtube is the
4.5" travel.

Thanks

Ron

I was not able to find anything with that thread available at the time (though it could have another name), and was going to see if I could machine one myself before losing steam. Definitely he could make an adapter for a moonlite focuser, but maybe there is something hidden on precise parts you could have made. Just a thought, hope that is helpful...

Cheers, eh!

Jeff
middlman avatar
middlman avatar
Did you ever resolve your focuser problem?  I have the stock focuser from mine as I replaced  it with a moonlite.   PM me if your interested,

-Kevin
Sean Mc avatar
Sean Mc avatar
Thanks Jeff. I managed to get through to a different support agent at ES who was helpful. They sourced me a pinion assembly fairly cheaply. 

i shoot narrowband, with a tiny sensor and the scope seems to do alright, but since it’s an fpl51 triplet I’ve decided that I won’t put money into it.

I’m going to save up for a SW 190MN