20" Skywatcher Stargate review

[sn1987a (Barry)]

28" setup 12 minutes

https://www.youtube.com/watch?v=tIPiotbD-ZA

[gaseous (Patrick)]

Nice setup Barry - really like the UTA connection. Bit agricultural, but so simple and effective! Like the George Smoot autograph inside the mirror cover too!

[Graeme Bluestar (Graeme)]

Aaron,
I don't think you will go too far wrong in purchasing one of these scopes - they are well priced. Purchased mine from Sirius Optics, happy to recommend them - good people & great service.

As has been pointed out in these forums, the best scope is the one you use the most. If you have nowhere to store in it assembled condition, you need to decide whether the effort involved in regular assembly will not become too much of a bother when you just want to spend an hour or two using it. For that reason I am starting to give serious consideration to building a permanent observatory for mine.

Patrick,
Will let you know what I figure out for the cooling fans, and will get some details on the cover bags I use for you.

Regards,
Graeme J.

[Joves (Aaron)]

Originally Posted by Graeme Bluestar

Aaron,
I don't think you will go too far wrong in purchasing one of these scopes - they are well priced. Purchased mine from Sirius Optics, happy to recommend them - good people & great service.

As has been pointed out in these forums, the best scope is the one you use the most. If you have nowhere to store in it assembled condition, you need to decide whether the effort involved in regular assembly will not become too much of a bother when you just want to spend an hour or two using it. For that reason I am starting to give serious consideration to building a permanent observatory for mine.

Patrick,
Will let you know what I figure out for the cooling fans, and will get some details on the cover bags I use for you.

Regards,
Graeme J.

Thanks Graeme.

I don’t foresee that it will see a whole heap of assembly/disassembly in the short term, as it will most likely see little use until the house we currently have being built is compete and I have a level garage/workshop to wheel it (assembled) in and out of.

Appreciate your advice and confirmed confidence in this particular scope! Thanks again.

Aaron

[FredinBroome (Fred)]

Thank you Graham for a wonderful review. It would be interesting to see if the 2018 - 2019 also had these failings. One would think that someone would have taken notice of the cosmetic details

[Graeme Bluestar (Graeme)]

Hi all,
A quick update on a couple of recent upgrades to my Stargate. I have now installed 3 x cooling fans behind the primary mirror - obtained from the local Jaycar agent:

3 x YX2523 80mm ball bearing fans @$24.95 each. (the more expensive Mag- Lev ones would probably be better) but I have not noticed any vibration issues so far with visual observing. The mirror cradle has provision for this size fan, with holes for the 4 attaching screws per fan already drilled and threaded. You will also need to obtain 12 s/steel cap screws for attachment.

3 x YX2511 safety grilles to suit @3.95 each.

You will also needed an applicable on/off switch - I am running 12V from a Powerpack through an LED toggle switch. Initially I was going to mount the switch and inlet cord socket near the main on/off switch located on the side box/cover panel. However after removing the cover to reveal all the moving gears, cabling etc. I decided to play it safe and fit them in a separate box externally. If you install this way be aware that you will need enough slack in the cabling from the control box to the fans to allow for altitude travel of the OTA. Also be careful the cabling does not entangle in the curved altitude rocker frame - I ran my cabling through it instead of over or under.

I found the control paddle cable to be barely long enough for normal use without using outstretched arms frequently. Searching my local area as to an off the shelf item proved fruitless, so $90.00 later I ended up with a custom made cable. Just be careful as to it's location when slewing the mount in the dark.

As has been mentioned earlier in this thread, the visual image does suffer from some coma. After weeks of keeping watch (unsuccessfully) on ISS for a used Parracorr I bit the bullet and ordered (and paid for) a new Skywatcher equivalent.

And woudn't you know it, a couple of days later a used Parracorr pops up for sale!

So now I have two that so far have only had a very quick test, with both showing a great improvement in image quality around the outer FOV.

Once I have a chance to give them more of a test drive I will put the results up here.

[gaseous (Patrick)]

Thanks Graeme, I've been eagerly awaiting a post from you regarding the cooling fans - would you please mind posting the specs of the relevant switch, cable connection, etc? I'm keen to do something identical to my scope. If you could put it in terms that the average 8 year old would understand, that would be greatly appreciated!


I'm only using a GSO coma corrector, but it makes a very significant improvement around the edge of field - I can only imagine that a new Paracorr is tidying your views up magnificently. Thanks again for your post.


Cheers,
Pat.

[Graeme Bluestar (Graeme)]

Pat,
Here are the Jaycar part numbers for the additional parts you will need -

ST0580 red LED illuminated toggle switch - $3.95
WQ7289 power input lead - with 12V cigarette lighter style plug - $7.95
PSO522 panel socket - for the other end of the above cable to plug into - $2.95
HB6015 Enclosure box - to mount the toggle switch & input cable panel socket - $4.95

Additional requirements are female crimp terminals to suit the above switch etc., a little bit of heatshrink tube, a couple of metres of twin core cable, some small black nylon zip ties and some solder splices - Narva #56380 ( I imagine Jaycar will have an equivalent for these)

I mounted the enclosure box with toggle switch and inlet plug on the scope side cover that carries the on/off mount drive switch/altitude lock wheel etc (at the opposite end to that switch). Be sure to leave enough power supply cable to the fans to allow mount travel from near horizontal to direct overhead. Use a little Velcro to attach it to the side cover just in case the cable does get entangled and tries to tear out of this box.

To mount the fans to the mirror cell see your local nut & bolt shop for the following-

12 x socket head cap screws M4 x 40mm long. Get them in 304 stainless steel if possible. Also 12 x M4 s/s flat washers to suit. This should cost you around $5.00 total.

Good Luck!!

[gaseous (Patrick)]

Originally Posted by Graeme Bluestar

Pat,
Here are the Jaycar part numbers for the additional parts you will need -

ST0580 red LED illuminated toggle switch - $3.95
WQ7289 power input lead - with 12V cigarette lighter style plug - $7.95
PSO522 panel socket - for the other end of the above cable to plug into - $2.95
HB6015 Enclosure box - to mount the toggle switch & input cable panel socket - $4.95

Additional requirements are female crimp terminals to suit the above switch etc., a little bit of heatshrink tube, a couple of metres of twin core cable, some small black nylon zip ties and some solder splices - Narva #56380 ( I imagine Jaycar will have an equivalent for these)

I mounted the enclosure box with toggle switch and inlet plug on the scope side cover that carries the on/off mount drive switch/altitude lock wheel etc (at the opposite end to that switch). Be sure to leave enough power supply cable to the fans to allow mount travel from near horizontal to direct overhead. Use a little Velcro to attach it to the side cover just in case the cable does get entangled and tries to tear out of this box.

To mount the fans to the mirror cell see your local nut & bolt shop for the following-

12 x socket head cap screws M4 x 40mm long. Get them in 304 stainless steel if possible. Also 12 x M4 s/s flat washers to suit. This should cost you around $5.00 total.

Good Luck!!

Brilliant, thanks Graeme!

[gaseous (Patrick)]

"Poor design of the counterweight attachment system – the single long bolt threaded straight into a thin cast area of the PMA base is probably not up to the job, especially if additional equipment/weight is fitted to the top end. I will be re-designing this setup in the future."


Graeme, you were spot on regarding this. My threaded slot for the hole has lost its thread, I assume due to the extra wear and tear from additional counterweights, and no amount of thread tape will allow the bolt to screw in. I have completely screwed through this hole with a 10mm bit, and have utilised a long threaded bolt to create a new fixing for the counterweights. I also had to increase the central holes in the supplied SW weights to suit the slightly wider bolt, but it feels a lot more secure now.

[david booth (david)]

ive heard bad things also there not up to the quality of sdm which you should be able to get second hand sdm 20 for the same money

[Joves (Aaron)]

Have you been happy with the optics, Patrick?

[gaseous (Patrick)]

Yes Aaron, very much so. The mirror takes a little while to reach ambient temperature, but the views are great and generally limited by the seeing conditions, not the quality of the mirror itself. I've made a list of personal gripes/complaints about the overall build quality and possible improvements of the scope, but once it's set up and humming along, the views are spectacular.

[Joves (Aaron)]

That’s great to hear, thanks Patrick.

I have one arriving imminently. Will be interesting to see if any improvements have been made. I’m imagining not, so this thread will be very helpful for some DIY fixes.