Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Mega-mod thread for Zhumell dobs

  • Please log in to reply
1527 replies to this topic

#1501 JagZilla

JagZilla

    Lift Off

  • -----
  • Posts: 4
  • Joined: 15 Sep 2020
  • Loc: Central Mississippi

Posted 06 October 2020 - 07:52 AM

The z10 I bought comes with a zhumell laser collimator. Ive heard alot of talk about how they arent very accurate and that they need collimating themselves.

Gevin,

 

I read those same things about the collimator, so when my Z10 arrived last week, I made a simple jig out of 4 wood screws and a scrap piece of 2x4. I checked it at a distance of 15ft (the arbitrary distance that my tool chest just happened to be from my garage door), and it was dead accurate. It could be that GSO has tightened their quality control in the years since those collimator reviews were written on this thread. I'll be interested to read if your test results are similar to mine.


  • Gevin likes this

#1502 sunrag

sunrag

    Messenger

  • *****
  • Posts: 450
  • Joined: 15 Sep 2019
  • Loc: Carmel, Indiana

Posted 06 October 2020 - 10:51 AM

The one I got with my AD12 last year was also very accurate out of the box (still is).


Edited by sunrag, 06 October 2020 - 10:51 AM.

  • JagZilla likes this

#1503 Gevin

Gevin

    Lift Off

  • -----
  • Posts: 12
  • Joined: 03 Oct 2020

Posted 08 October 2020 - 03:38 AM

Ive been studying these push to kits and have come to a dead end on deciding which one to buy. The romer optics ez push to kit specifically fits the zhumell z series. I really want the dobson dream 8 on my z10 because it uses sky safari but not sure how to make it work without drilling a hole through the plastic cap on the bearing to put a bolt through and still not so sure that will work. If anyone has installed the dobson dream 8 or even dobson dream 4 on any of the zhumell z series can u please tell me how you made it work. Any help with this matter is greatly appreciated

#1504 Gevin

Gevin

    Lift Off

  • -----
  • Posts: 12
  • Joined: 03 Oct 2020

Posted 08 October 2020 - 03:47 AM

My z10 arrived this afternoon and i already had made a jig waiting for it to arrive..i to uses my garage door at about 15 feet as thats where i had my saw horses set up and to my surprise it was dead accurate as well. My z10 was just a hair off from being on the money as well. Thats even after being shipped from california to tennessee. I was shocked. I got some good views with it tonight but really need to get a push to system as my town is so light polluted that you can only see a few planets and about 5 stars. Kind of hard to use a finder scope when there isnt much to see. Would really like to see some nebula and better views of Andromeda as i luckily stumbled across that. I have a light pollution filter but does no good when you have no idea where to point to see what you want
  • JagZilla likes this

#1505 keel59

keel59

    Lift Off

  • -----
  • Posts: 4
  • Joined: 28 Apr 2020
  • Loc: San Marcos, TX

Posted 12 October 2020 - 03:11 PM

Ive been studying these push to kits and have come to a dead end on deciding which one to buy. The romer optics ez push to kit specifically fits the zhumell z series. I really want the dobson dream 8 on my z10 because it uses sky safari but not sure how to make it work without drilling a hole through the plastic cap on the bearing to put a bolt through and still not so sure that will work. If anyone has installed the dobson dream 8 or even dobson dream 4 on any of the zhumell z series can u please tell me how you made it work. Any help with this matter is greatly appreciated

I recently installed the DobsonDream 4 on my Z8. Astro Gadgets makes a DobsonDream 4 specifically for the GSO Dobs. The difference on the GSO kit is one bolt that that goes through the alt bearing housing. You lose the clutch and cap on one side. It works well. I was worried about the nylon bearing in the hub that doesn't have anything the keep it from slipping out in this config. So I drilled a large hole through the center of the cap (to clear the kit's bolt head) and screwed it back on without the clutch bearing and washers. It works well.


  • Gevin likes this

#1506 keel59

keel59

    Lift Off

  • -----
  • Posts: 4
  • Joined: 28 Apr 2020
  • Loc: San Marcos, TX

Posted 12 October 2020 - 03:55 PM

I recently installed the DobsonDream 4 on my Z8. Astro Gadgets makes a DobsonDream 4 specifically for the GSO Dobs. The difference on the GSO kit is one bolt that that goes through the alt bearing housing. You lose the clutch and cap on one side. It works well. I was worried about the nylon bearing in the hub that doesn't have anything the keep it from slipping out in this config. So I drilled a large hole through the center of the cap (to clear the kit's bolt head) and screwed it back on without the clutch bearing and washers. It works well.

Some pics.

altbearing.jpg cap.jpg capinstalled.jpg installed.jpg


  • Sol Robbins, Ohmless and Gevin like this

#1507 sunrag

sunrag

    Messenger

  • *****
  • Posts: 450
  • Joined: 15 Sep 2019
  • Loc: Carmel, Indiana

Posted 12 October 2020 - 07:48 PM

You guys should try the Romer Optics EZ Push-to system. It installs easily without any irreversible modifications and minimal drilling (just 4 tiny screw holes per axis). In my experience the Goto has been more accurate than my HEQ5 mount and takes far less time to do the initial alignment. (I am not affiliated with Romer Optics.  I have installed it both on factory standard AD12 and a Z8 with a home made dob base).


  • Phil1 and Gevin like this

#1508 Gevin

Gevin

    Lift Off

  • -----
  • Posts: 12
  • Joined: 03 Oct 2020

Posted 16 October 2020 - 03:06 AM

Thanks keel59. I purchased the dobson dream 8 from astro gadgets like 7 days ago and received an email yesterday that it shipped. Now its just the waiting game. Hopefully it arrives in a timely manner and I get some clear days to use it as its been cloudy and rainy alot here lately. I do have a question for you though. Did you have to download sky safari pro or did it work on the regular version?

Edited by Gevin, 16 October 2020 - 03:42 AM.


#1509 Maxtrixbass

Maxtrixbass

    Messenger

  • *****
  • Posts: 406
  • Joined: 28 Feb 2016
  • Loc: Camano Island, WA

Posted 17 October 2020 - 09:46 PM

You guys should try the Romer Optics EZ Push-to system. It installs easily without any irreversible modifications and minimal drilling (just 4 tiny screw holes per axis). In my experience the Goto has been more accurate than my HEQ5 mount and takes far less time to do the initial alignment. (I am not affiliated with Romer Optics.  I have installed it both on factory standard AD12 and a Z8 with a home made dob base).

For future lurkers...

 

I have a Z12 and bought the Romer Optics push to. If your scope is one their list installation will be a breeze. I use the andriod app on a kindle and it works great and is easy to get running. I tried the Stellarium on PC route and got it to work, but I don't think it saves the settings like the app.

 

I was pleased with the accuracy. With a CC I'm at ~1600mm fl and with a 25mm 2" eyepiece the target was always in view.

 

All in all I would give the system two thumbs up, especially for the money.


Edited by Maxtrixbass, 17 October 2020 - 09:48 PM.

  • JagZilla likes this

#1510 keel59

keel59

    Lift Off

  • -----
  • Posts: 4
  • Joined: 28 Apr 2020
  • Loc: San Marcos, TX

Posted 18 October 2020 - 12:35 PM

Thanks keel59. I purchased the dobson dream 8 from astro gadgets like 7 days ago and received an email yesterday that it shipped. Now its just the waiting game. Hopefully it arrives in a timely manner and I get some clear days to use it as its been cloudy and rainy alot here lately. I do have a question for you though. Did you have to download sky safari pro or did it work on the regular version?

I downloaded Sky Safari Plus. The free version doesn't provide telescope support.


  • Gevin likes this

#1511 Gevin

Gevin

    Lift Off

  • -----
  • Posts: 12
  • Joined: 03 Oct 2020

Posted 18 October 2020 - 07:10 PM

I downloaded Sky Safari Plus. The free version doesn't provide telescope support.





Thanks..I didnt figure it did. Figured I would download the sky safari pro. Its only 20 bucks so not to bad. Getting so anxious waiting on them to arrive. Still hung up in customs

#1512 graffias79

graffias79

    Viking 1

  • -----
  • Posts: 629
  • Joined: 01 Oct 2010
  • Loc: Madison, WI

Posted 23 October 2020 - 03:12 PM

Gevin,

 

I read those same things about the collimator, so when my Z10 arrived last week, I made a simple jig out of 4 wood screws and a scrap piece of 2x4. I checked it at a distance of 15ft (the arbitrary distance that my tool chest just happened to be from my garage door), and it was dead accurate. It could be that GSO has tightened their quality control in the years since those collimator reviews were written on this thread. I'll be interested to read if your test results are similar to mine.

I got my Z10 in January of 2011 and when I checked the collimation on my laser collimator it was dead accurate as well.  In fact, it still is spot on (pardon the pun)



#1513 CTerry

CTerry

    Lift Off

  • -----
  • Posts: 8
  • Joined: 05 Oct 2020

Posted 27 October 2020 - 12:50 PM

This is an amazing thread. I have a Z8 and i love it. its nice to see all the neat things people have done to their scopes.  I think we should start another thread thats all about how tos for dobs.  less random chatter and more pics and instructions.  that would be sweet to have.



#1514 keel59

keel59

    Lift Off

  • -----
  • Posts: 4
  • Joined: 28 Apr 2020
  • Loc: San Marcos, TX

Posted 31 October 2020 - 10:29 AM

I got my Z10 in January of 2011 and when I checked the collimation on my laser collimator it was dead accurate as well.  In fact, it still is spot on (pardon the pun)

My Zhumell laser was was also accurate. But the problem I have is the collimator is a loose fit in the focuser tube. So when I insert it and rotate it in the focuser the dot moves around the center mark on the main mirror. Collimating with the laser never agrees with collimation using my Cheshire. I recently tried user the laser with a Barlow lens and it works a little better.



#1515 Chucky

Chucky

    Apollo

  • *****
  • Posts: 1,162
  • Joined: 16 Apr 2010

Posted 31 October 2020 - 04:52 PM

(( I insert it and rotate it in the focuser the dot moves around the center mark on the main mirror. ))

Unacceptable.  Poor registration. 


Edited by Chucky, 31 October 2020 - 04:53 PM.


#1516 Edward Swaim

Edward Swaim

    Vostok 1

  • -----
  • Posts: 102
  • Joined: 29 Oct 2010
  • Loc: Little Rock, Arkansas

Posted 02 November 2020 - 07:17 PM

Just put a new GSO mirror in mine. The original mirror had craters in it from the secondary falling onto it during shipping from the auction-site seller. That mirror worked fine for several years. A recoat was starting to dim, so I put a shiny new mirror in it. 

 

Other modifications: base from recycled cabinet doors, azimuth circle illuminated by LED strip light, eyepiece holders, casters, a Rod Nabholz Wixey bracket, speaker-magnet counterweight, green laser finder, repositioned finder bracket, and lots of stickers. 

 

There's a little swing-out table for a tablet to run Sky Safari. 

 

It lives on the deck in a Rubbermaid storage box with an appliance bulb to try to keep moisture down.

Attached Thumbnails

  • Telescope.jpg

Edited by Edward Swaim, 02 November 2020 - 07:19 PM.

  • Solar storm, sunrag and JagZilla like this

#1517 JagZilla

JagZilla

    Lift Off

  • -----
  • Posts: 4
  • Joined: 15 Sep 2020
  • Loc: Central Mississippi

Posted 03 November 2020 - 11:06 PM

Just put a new GSO mirror in mine. The original mirror had craters in it from the secondary falling onto it during shipping from the auction-site seller. That mirror worked fine for several years. A recoat was starting to dim, so I put a shiny new mirror in it. 

 

Other modifications: base from recycled cabinet doors, azimuth circle illuminated by LED strip light, eyepiece holders, casters, a Rod Nabholz Wixey bracket, speaker-magnet counterweight, green laser finder, repositioned finder bracket, and lots of stickers. 

 

There's a little swing-out table for a tablet to run Sky Safari. 

 

It lives on the deck in a Rubbermaid storage box with an appliance bulb to try to keep moisture down.

That's a nice rig. Do the cabinet doors make for a lighter base than the stock press-board? Where did you get all those stickers? I would love to get a bunch like those for my grand kids to put all over the OTA.



#1518 Edward Swaim

Edward Swaim

    Vostok 1

  • -----
  • Posts: 102
  • Joined: 29 Oct 2010
  • Loc: Little Rock, Arkansas

Posted 11 November 2020 - 02:56 PM

Scott,

 

I used the cabinet doors, because they are $2 each at my local Habitat for Humanity ReStore, and I liked the look. I never had a stock base, so I don't know the weight comparison. It is quite heavy!

 

Any sticker I find--dollar store, special events, stores, Happy Meals, I put on the telescope. Back when we could have public outreach sessions, kids loved them. 

 

Ed



#1519 jessebear

jessebear

    Vostok 1

  • *****
  • Posts: 188
  • Joined: 01 Oct 2019
  • Loc: Grand Junction, CO

Posted 15 November 2020 - 11:36 PM

I guess it's a 'mod'! Poncet platform in the works. Electronics are mostly here and the extrusion should be in next week. Now to find time to print. I think I'll be removing my EZ Push-To system to use this though since I might need the azimuth lock knob again. I don't use the EZ Push-To anyway.

 

 tHABRIY.png

 

I made a separate thread but maybe should have just asked here. Anyone move the primary mirror on a Z10/AD10 for DSLR focus? It seems like 2" is plenty for the Z12/AD12. I've shaved off 11mm on the focuser side and I'm hoping to move the mirror as little as possible.



#1520 CowTipton

CowTipton

    Sputnik

  • -----
  • Posts: 39
  • Joined: 27 Jul 2020
  • Loc: NW Chicago Suburbs

Posted 16 November 2020 - 05:01 PM

I have an AD8.  It came with the laser collimater.

So far it seems to be working just fine and my viewing has been pretty good.

But of course who can be satisfied with that?

 

Question:

 

Can you check the laser's collimation by aligning your secondary (red dot in the target O at the center of the primary) and then rotating the laser in the focuser?

If it's off you should see the red dot moving in a circular pattern on the primary, and if it's aligned the dot should stay in place, no?

 

Why can't the focuser and secondary be your jig?


  • Cames likes this

#1521 Waynosworld

Waynosworld

    Mariner 2

  • *****
  • Posts: 269
  • Joined: 22 Oct 2020

Posted 16 November 2020 - 08:32 PM

That is how I check mine now, the first time I made a jig and my cheapo laser was collimated just fine.

 

I have an AD8.  It came with the laser collimater.

So far it seems to be working just fine and my viewing has been pretty good.

But of course who can be satisfied with that?

 

Question:

 

Can you check the laser's collimation by aligning your secondary (red dot in the target O at the center of the primary) and then rotating the laser in the focuser?

If it's off you should see the red dot moving in a circular pattern on the primary, and if it's aligned the dot should stay in place, no?

 

Why can't the focuser and secondary be your jig?



#1522 jessebear

jessebear

    Vostok 1

  • *****
  • Posts: 188
  • Joined: 01 Oct 2019
  • Loc: Grand Junction, CO

Posted 16 November 2020 - 11:48 PM

That's not a bad way to quickly check the collimation but I'd find it awkward to adjust the laser's collimation with it mounted in the focuser. Making a jig also lets you check the collimation over a much longer distance and increase its accuracy.

I 3D printed a jig and checked it across my garage against a piece of paper on the wall where I'd marked how far off center each of the 3 adjustment points were. A small refractor trained on the laser spot helped to really see what I was doing over a large distance and I could make small adjustments at a time while rotating the collimator in the jig.
  • wrvond likes this

#1523 CowTipton

CowTipton

    Sputnik

  • -----
  • Posts: 39
  • Joined: 27 Jul 2020
  • Loc: NW Chicago Suburbs

Posted 17 November 2020 - 09:29 PM

So yea I tried it this afternoon and there’s just too much play between the collimator and the focuser.  I can center the dot with the thumbscrews snugged but once loosened the dot moves out of the ring.  I always do snug my eyepieces so I guess that’s close enough.

 

Quick question that I didn’t see answered as I’ve perused this thread:

 

Does anyone know what drill size hole is needed for the milk jug washers to fit around the center screw holding the secondary?

I’d like to try it without removing the secondary mirror altogether by cutting a slit across one radius of the washers.

For an AD8 (same as Z8 I assume)



#1524 Waynosworld

Waynosworld

    Mariner 2

  • *****
  • Posts: 269
  • Joined: 22 Oct 2020

Posted 17 November 2020 - 10:36 PM

When I spin my laser in the focus mechanism hole I put my finger lightly on the end of the laser to keep it flush in the hole while spinning it, but the first time I used a jig to see if the laser was collimated, I used almost a 20' gap between the laser and the paper target and it was perfectly collimated.

 

 

So yea I tried it this afternoon and there’s just too much play between the collimator and the focuser.  I can center the dot with the thumbscrews snugged but once loosened the dot moves out of the ring.  I always do snug my eyepieces so I guess that’s close enough.

 

Quick question that I didn’t see answered as I’ve perused this thread:

 

Does anyone know what drill size hole is needed for the milk jug washers to fit around the center screw holding the secondary?

I’d like to try it without removing the secondary mirror altogether by cutting a slit across one radius of the washers.

For an AD8 (same as Z8 I assume)


  • CowTipton likes this

#1525 Crankyanken

Crankyanken

    Lift Off

  • -----
  • Posts: 13
  • Joined: 26 Oct 2020
  • Loc: 36°48'08.5"N 108°09'24.3"W

Posted 18 November 2020 - 12:54 PM

When I spin my laser in the focus mechanism hole I put my finger lightly on the end of the laser to keep it flush in the hole while spinning it, but the first time I used a jig to see if the laser was collimated, I used almost a 20' gap between the laser and the paper target and it was perfectly collimated.

I ended up using the scope itself to collimate the laser, since I could see the circle it was creating (aperture stop, barlowed), I was able to make the necessary adjustments to the grub screws.  I removed the barlow and the laser was dead center with the adapter installed.  I also put a piece of scotch tape around the insertion end of the laser which really helped pick up some of the slop.  Collimation of the primary was a snap after that.


Edited by Crankyanken, 18 November 2020 - 12:56 PM.

  • CowTipton likes this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics