105 replies to this topic

[lowroller21]

Hi gang!

 

Just picked up this Starfinder with 3 eyepieces and a 2x Barlow for $200.  It's been crate stored since new so is in great shape, besides a bit of yellowing.

 

This is my first large scope and I read every post here before deciding to make an offer.  It needs a little cleanup, including the mirror, but I'm hoping to get it all set up and in the yard this weekend.

 

 

[junomike]

Good deal IMO.  Be sure to follow up on what you think (under the Stars).

[vtornado]

That is a beauty.

 

Why don't scopes like this come up by me???

All I get is the 500x 60mm vamboozler model for $100.00 firm

[lowroller21]

Thanks I'm pretty happy with it.  I had a few offers out there for a 6 or 8 inch dob that fell through, so this is a good find.

 

Considering refinishing the tube, but am just going to get it up and running for now.

[lowroller21]

The rod holding the counterweight is pretty rusty and I'd like to remove and clean it, or replace it.  I'm not really sure how its attached though and can't find a manual online.

 

Any ideas?

[Gil V]

Had one, sold it, wish I didn’t.

[CHASLX200]

That is a beauty.

 

Why don't scopes like this come up by me???

All I get is the 500x 60mm vamboozler model for $100.00 firm

All i get is junk also in my area or scopes that are priced 3 times higher than anywhere else.

[starman876]

I think the rod screws in.   Depending how rusty the rod and counterweight are will be the degree of difficulty of separating them. I had to use  a 20 ton press one time.   Soak then in a rust remover first and then penetrating oil like PB blaster and see what happens.

[macdonjh]

I think the rod screws in.   Depending how rusty the rod and counterweight are will be the degree of difficulty of separating them. I had to use  a 20 ton press one time.   Soak then in a rust remover first and then penetrating oil like PB blaster and see what happens.

+1

 

I'll also vouch for the effectiveness of Corrosion-X.  Once you get everything separated, Naval Jelly will remove the rust (as will other products).  Since you'll likely have a consistent load on your mount you could do something as simple as paint your counter weight shaft with silver paint to spruce it up.

[Stevegeo]

I had one as well, it was very neglected when I got it , sat on an open porch next to lake Ontario for 20 yrs, .

Tube was mush. But the mirror and secondary was perfect  as they were removed and wrapped. 

After a complete refurbish with a new tube , which I redid in fiberglass, and a new focuser.  New stainless hardware and a repaint of the base. Finally a laser collimation.... a great scope.... do I regret selling? Yes in a way. But it's not a beast to keep locked away... it needed to be used.. and sitting in my living room then kitchen then back room wasn't doing  it justice.

I did buy in its place a Meade SN 10  then a Celestron C11  for the observatory..

 

Stevegeo 

[Stevegeo]

Advice,, as been there and tried that...

As a machinist, fabricator... dont remove the rod...or attempt to ... slide the weights off.. with steel wool and WD40  work the rust off the rod.

Wipe  and keep at it.  When it looks like it wont clean up any further. Stop.  Wipe down really well and paint..

I would suggest epoxy appliance  paint, it's tough as nails.  Wait at least 24 hours... then the counter weights..

 

And you may decide to paint them as well.

 The Starfinder  is an excellent scope  and a good collimate will bring out the best.

Enjoy!

Stevegeo 

[lowroller21]

Big day yesterday!

 

Time to take a look at the mirror:

 

Got everything out okay.  I marked the mirror edges prior to removing, and backed off the plastic set screws exactly one turn.  It was pretty dirty.

 

Cleaned it in the kitchen sink.  Let it soak for 10 minutes, swirled it around, rinsed with tap water, lightly cleaned with cotton balls, then rinsed with distilled water.  Blew it dry with my compressor.  Made a 10" square, punched a hole in the center, and marked the mirror.  Very happy with the result!

 

Markings on the back of the mirror.  Any idea what they mean?

 

I didn't end up removing the secondary; just blew it off with the compressor.  I think the tube will eventually get restored so I'll tackle all that then.

 

The base is in great shape; doesn't need any paint.  I cleaned up the whole thing and ended up using multiple grits of sandpaper strips to take the rust off the rod.  Before and after:

 

There are a few bolts with rusty heads.  I measured them all and will replace with stainless once I make it to the hardware store.

 

 

Edited by lowroller21, 13 April 2020 - 08:50 AM.

[lowroller21]

So then I hauled this beast to the backyard and zeroed the star finder on the tip of a power pole.  

 

Wish I could say that everything went great, but that wasn't the case.  I couldn't find anything decent to look at, couldn't get the eyepiece into a good position, and I sheared the bolt on the forward strap!  Who designed those?  Ridiculous.  Not a good first attempt.

 

But fast forward to this morning...

 

I woke up at 0330 - couldn't sleep so I went to the garage.  Opened the door, tied the scope to the mount (which is much more secure than it was last night!) and look what I found

 

I stargazed from 0400 right until 0700.

 

I saw the rings of Saturn for the first time.

 

I saw the bands on Jupiter, and its moons for the first time.

 

I saw a double star.

 

I showed a morning jogger Saturn and blew his mind.

 

And I saw the moon with greater clarity than every before.  Cell phone pic through the lens:

 

Overall impression of the scope is that I love it!  I had been trying to find an XT8 but this thing is the best.  Once you get that incredibly heavy base in position it works like a dream.  The balance is excellent and it moves easily.  The drive motor works flawlessly and I don't know if I could do without one now.  I'd put a planet into the eyepiece, go get a cup of coffee, and it would still be centered 10 minutes later! 

 

That said, there are a couple of issues.  First is the focus adjuster.  I'd read that it was a POS and thought it would be fine, but trying to dial in the focus with a 9mm lens was tough.  If there are suggestions for a good focuser that is less than $100 (preferably closer to $50) I'd love to hear it.

 

Second is the straps.  No way am I paying $200+ for a set of rings, but something needs to happen.  I'm thinking pelican hook and small turnbuckle, but will see what I can find at the hardware store.  The rope works really well, but isn't a very elegant solution.

 

I'd also love to get a clearer picture at higher zoom, but understand that with a short focal point this may not be possible?  My best images were using the 2x barlow and 25mm lens.  The 2 x 12mm lens started to get a little blurry, and with the 9mm it was impossible to hit the focus point just right.  Would a 3x barlow help or am I at my limit?

 

Very happy overall.  Any suggestions of what I should look for tonight?  

 

[CHASLX200]

 

So then I hauled this beast to the backyard and zeroed the star finder on the tip of a power pole.  

 

 

Wish I could say that everything went great, but that wasn't the case.  I couldn't find anything decent to look at, couldn't get the eyepiece into a good position, and I sheared the bolt on the forward strap!  Who designed those?  Ridiculous.  Not a good first attempt.

 

But fast forward to this morning...

 

I woke up at 0330 - couldn't sleep so I went to the garage.  Opened the door, tied the scope to the mount (which is much more secure than it was last night!) and look what I found

 

 

I stargazed from 0400 right until 0700.

 

I saw the rings of Saturn for the first time.

 

I saw the bands on Jupiter, and its moons for the first time.

 

I saw a double star.

 

I showed a morning jogger Saturn and blew his mind.

 

And I saw the moon with greater clarity than every before.  Cell phone pic through the lens:

 

 

Overall impression of the scope is that I love it!  I had been trying to find an XT8 but this thing is the best.  Once you get that incredibly heavy base in position it works like a dream.  The balance is excellent and it moves easily.  The drive motor works flawlessly and I don't know if I could do without one now.  I'd put a planet into the eyepiece, go get a cup of coffee, and it would still be centered 10 minutes later! 

 

That said, there are a couple of issues.  First is the focus adjuster.  I'd read that it was a POS and thought it would be fine, but trying to dial in the focus with a 9mm lens was tough.  If there are suggestions for a good focuser that is less than $100 (preferably closer to $50) I'd love to hear it.

 

Second is the straps.  No way am I paying $200+ for a set of rings, but something needs to happen.  I'm thinking pelican hook and small turnbuckle, but will see what I can find at the hardware store.  The rope works really well, but isn't a very elegant solution.

 

I'd also love to get a clearer picture at higher zoom, but understand that with a short focal point this may not be possible?  My best images were using the 2x barlow and 25mm lens.  The 2 x 12mm lens started to get a little blurry, and with the 9mm it was impossible to hit the focus point just right.  Would a 3x barlow help or am I at my limit?

 

Very happy overall.  Any suggestions of what I should look for tonight?  

 

I have used over 1000x with fast Newts. If it is a very good mirror and collimation is dead on and it is cooled to the outside temp then 450x to 600x would be easy with a 10". The moon can take 600x easy on that scope and Jupiter 450x. Also need to have steady seeing for powers that high.

 

Get a good used 5 to 3mm Radian and a barlow.  Most nites that scope will do best at around 300x for the planets and lower powers for deep sky. 

 

You may find some used rings that may fit the tube for much cheaper than $200.
 

[lowroller21]

I have used over 1000x with fast Newts. If it is a very good mirror and collimation is dead on and it is cooled to the outside temp then 450x to 600x would be easy with a 10". The moon can take 600x easy on that scope and Jupiter 450x. Also need to have steady seeing for powers that high.

 

Get a good used 5 to 3mm Radian and a barlow.  Most nites that scope will do best at around 300x for the planets and lower powers for deep sky. 

 

You may find some used rings that may fit the tube for much cheaper than $200.
 

My 9mm with the 2x barlow is about 250x but the image wasn't very crisp.  Is that a function of the lens? I'd love to get the planets at those kinds of magnification.

 

Collimation seems good as far as I can tell.  I've ordered a laser so will dial it in when that arrives.

 

Where is a good place to shop for used equipment?  Ebay didn't yield much of anything.

 

Appreciate the help!

 

Edit: Seems like the classifieds right here are pretty good!  

Edited by lowroller21, 13 April 2020 - 10:07 AM.

[CHASLX200]

My 9mm with the 2x barlow is about 250x but the image wasn't very crisp.  Is that a function of the lens? I'd love to get the planets at those kinds of magnification.

 

Collimation seems good as far as I can tell.  I've ordered a laser so will dial it in when that arrives.

 

Where is a good place to shop for used equipment?  Ebay didn't yield much of anything.

 

Appreciate the help!

 

Edit: Seems like the classifieds right here are pretty good!  

Could be seeing or the scope was not cooled.  A mushy image can be caused by a scope with a warmer mirror than the outside air and or bad seeing.  On a F/4.5 mirror collimation has to be dead on.  Slower mirrors can get away with collimation being off a little, but the faster the optic then collmiation has to be spot on.  You will also have coma so a used Paracorr will help a bunch. Coma seems to vary by person as some can live with it at F/4.5. But i have to have a Paracorr at anything faster than F/5.6.  If the image stays mushy no mattter what , then it could be a not so great mirror. I had the 8" Starfinder and most Meade mirrors from that time seemed to be pretty to very good. If you are viewing inside the garage like the pic you posted then seeing effects will mush up a image.

 

 

 

This site has plenty of used stuff for sale and Astromart.  I buy used 97% of the time.

Edited by CHASLX200, 13 April 2020 - 10:42 AM.

[lowroller21]

Could be seeing or the scope was not cooled.  A mushy image can be caused by a scope with a warmer mirror than the outside air and or bad seeing.  On a F/4.5 mirror collimation has to be dead on.  Slower mirrors can get away with collimation being off a little, but the faster the optic then collmiation has to be spot on.  You will also have coma so a used Paracorr will help a bunch. Coma seems to vary by person as some can live with it at F/4.5. But i have to have a Paracorr at anything faster than F/5.6.  If the image stays mushy no mattter what , then it could be a not so great mirror. I had the 8" Starfinder and most Meade mirrors from that time seemed to be pretty to very good. If you are viewing inside the garage like the pic you posted then seeing effects will mush up a image.

 

 

 

This site has plenty of used stuff for sale and Astromart.  I buy used 97% of the time.

Dang, those are spendy...  Is there an off brand version or cheaper solution I should look at?  I'm fine with spending some money, but those are worth more than I paid for my whole kit!  

 

I've got a collimator on the way so I'll dial that in first.  I feel like the mirror is good.  I didn't notice any coma but also didn't know to look.

 

Any opinion on the Celestron X-Cel 2.3mm eyepiece, instead of the TeleVue 3mm?  There is one in the classifieds sitting at $50 which is about all I can bear right now.  I'd also like to get a crayford style focuser to replace the plastic one I have currently, and some filters, so things are adding up.

Edited by lowroller21, 13 April 2020 - 01:27 PM.

[Terra Nova]

The TV Delites are quite nice. I have the 3mm and the 4mm that I use in my TV Genesis SDF. I doubt you would be disappointed with the 3mm.

[Stevegeo]

Back to the straps again.. both mine were in  very rough shape after sitting out all those years..

I made copies with thin stainless straps and 1 /4 -20 stainless bolts welded on ..  

And the focuser was as you said a pos .. I had another I bought at NEAF last year but kept it as the new owner insisted he was going to use one he had .. as it was I ended up using the new focuser only Meade SN10 ..

 

If you take it out and give it time to acclimate to the temp  , you'll find it's a very amazing instrument worth keeping .

I did replace the plastic lock handle on the mount with a nice chrome unit , a nice upgrade and cheap..

 

You'll find  the more you take it out, the more you'll enjoy it.

Have fun..

Stevegeo 

[CHASLX200]

Dang, those are spendy...  Is there an off brand version or cheaper solution I should look at?  I'm fine with spending some money, but those are worth more than I paid for my whole kit!  

 

I've got a collimator on the way so I'll dial that in first.  I feel like the mirror is good.  I didn't notice any coma but also didn't know to look.

 

Any opinion on the Celestron X-Cel 2.3mm eyepiece, instead of the TeleVue 3mm?  There is one in the classifieds sitting at $50 which is about all I can bear right now.  I'd also like to get a crayford style focuser to replace the plastic one I have currently, and some filters, so things are adding up.

Scan or sweep at low power and you will notice stars that are not sharp near the field edge. I have seen some used Paracorr's for around $150. A X cel is much cheaper and should do fine. 2.3mm is something you won't use much unless you have steady seeing.

Edited by CHASLX200, 13 April 2020 - 06:04 PM.

[astrowolf67]

The rod holding the counterweight is pretty rusty and I'd like to remove and clean it, or replace it.  I'm not really sure how its attached though and can't find a manual online.

 

Any ideas?

I removed the shaft from an 8" I've been working on.  The counterweight shaft, is the declination shaft.  It runs through the mount housing, and into the tube cradle.  It was a bear to get removed.  The tube cradle is held in place with set screws, and the fit of the declination shaft was so tight, it required some heat, and hammering, to get it free.

 

You did the right thing, removing rust from the mount down.  I wouldn't remove it unless you are doing a complete teardown.  There could be some rust internally, but, most likely, it will be rust free on the bearing/bushing contact surface.

[Bomber Bob]

First of all, Welcome to The Classics on Cloudy Nights!

 

Second, Congratulations! on a great deal.

 

Third, these SF mounts are very easy to work on:

 

 

This is the 2nd SF that I bought, and had the Magellan DSC system added to it.  As posted already, the DEC shaft is also the counterweight shaft, and it slides in/out through those bushings.  The setting circle has a tiny grub screw in its collar that holds it on, and the circle keeps that 1" steel rod in place.  Simple!

 

Both of my SF mounts came with those steel bands... I got rid of all that.  I cut off the saddle-ends, and adapted Scopetronix 16" x 4" aluminum plates to the remaining square:

 

 

I hope your 10" SF has mirrors as good as my Model 826.  I just came in from grabbing galaxies with mine, and the views were fantastic.

 

One is on a 5' pedestal for refractors & CATs, and the other is on a standard height SF pedestal for my Newts.

Edited by Bomber Bob, 13 April 2020 - 10:31 PM.

[lowroller21]

Went out again last night and saw M42 for the first time.  Loving the scope.

 

Looks like a mounting solution has moved to the top of my list.  The supplied straps have a threaded rod notched to fit, then held on with a teeny tiny little pin.  The one that remains on the mount is cracked so it is just a matter of time.

 

The diameter is 12.7 inches.  I can't afford the parallax rings so am considering other options...

[astrowolf67]

Are the straps breaking, or just the bolts?  I have not reached that point of being able to remount my OTA on my 8".  I'm just curious what I am getting into.  The mount for mine, had been left outside for quite some time.

[Stevegeo]

If this helps ,  may not .. but if you can find a HVAC outfit. They may have a strap that may fit . The ones I found were locking types , pull tite then lock..  about 5 for the pair . I think they were ment to hold insulation onto ducting . 

I happen to be in a big box store lurking about when it came to me .. one of mine broke and not wanting to chance a fall , bought a strap I adapted to work ..I backed that one up with a hose clamp , just in case .. until I could find another solution . 

Later that week I happened to find stainless straps long enough and welded up a pair with stainless screws .   I didn't care for the whiney stainless against the white tube, so a coat of appliance epoxy paint finished them off . 

Stevegeo