Does this spider and secondary look right?

[RobertI]

I recently purchased a used 130P OTA (from a SkyProdigy) and trying to collimate the damn thing. Decided to take the spider cell off to check everything. Now I’ve never really examined a spider and secondary like this as my existing Newts as collimate perfectly, so two questions: Firsty do the spider vanes look right? They seem lop sided or possibly back to front or something. I can’t see how the centre ‘hub’ could ever be parallel with the tube when the vanes are like this. Secondly is it normal for the secondary to be mounted to one side in this way (last picture)? Any thoughts appreciated. 
 

[RobertI]

In fact I’ve remounted secondary and you can see it’s not parallel to the tube ….

 

Edited July 7 by RobertI

[ONIKKINEN]

Looks like the vane on the left is upside down, the flatter edge is to the bottom instead of the top as in the right. If its not glued in you could unscrew it and remount it the right way up and that would fix it, at least just by looking at the pictures.

It can still be collimated like this, since you have adjustment available on all axis of the secondary with the adjustment screws. More of a chore though, so i would fix the vane first.

Edited July 7 by ONIKKINEN

[RobertI]

Thanks for the reply, unfortunately they can’t be turned around as the screws are to one side, so the vane would end up being offset (see photo). I have the strangest feeling that a previous owner actually ‘refigured’ two of the vanes in order to mount them back to front. What on earth is going on! 

 

Edited July 7 by RobertI

[ONIKKINEN]

31 minutes ago, RobertI said:

Thanks for the reply, unfortunately they can’t be turned around as the screws are to one side, so the vane would end up being offset (see photo). I have the strangest feeling that a previous owner actually ‘refigured’ two of the vanes in order to mount them back to front. What on earth is going on! 

 

Yeah, that wouldn't work like this, definitely would create more issues than solve. I doubt you can bend the part that the screws go through 180 degrees without it breaking either.

I also wonder how it ended like this, just seems wrong. Manufacturing mistake perhaps?

One option is to replace the spider if you cant figure out how to fix it, TS sells spiders of all shapes and sizes, for example here: https://www.teleskop-express.de/en/telescope-accessories-5/telescope-diy-improvement-299/telescope-making-mechanical-parts-64?next_page=4

Edited July 7 by ONIKKINEN

[RobertI]

22 minutes ago, ONIKKINEN said:

Yeah, that wouldn't work like this, definitely would create more issues than solve. I doubt you can bend the part that the screws go through 180 degrees without it breaking either.

I also wonder how it ended like this, just seems wrong. Manufacturing mistake perhaps?

One option is to replace the spider if you cant figure out how to fix it, TS sells spiders of all shapes and sizes, for example here: https://www.teleskop-express.de/en/telescope-accessories-5/telescope-diy-improvement-299/telescope-making-mechanical-parts-64?next_page=4

Thanks @ONIKKINEN, that’s a useful link. Annoyingly they have budget spiders for 4.5” and 6” Newts only, neither of which will quite fit. They have the more expensive spiders in the right size but will end up costing twice as much as the scope itself so not really worthwhile. I think bending the flange to the correct side might be the only option. It was only a spur of the moment purchase anyway, I thought it would be nice for my old SkyProdigy mount to be reunited with a nice red SkyProdigy OTA 😕

[Second Time Around]

I'd be very surprised if  Beacon Hill Telescopes can't help you.  Go to http://beaconhilltelescopes.org.uk/pricelist.html for an old price list or for contact details go to http://beaconhilltelescopes.org.uk/contact.html

They do custom work as well.

Edited July 7 by Second Time Around

[RobertI]

52 minutes ago, Second Time Around said:

I'd be very surprised if  Beacon Hill Telescopes can't help you.  Go to http://beaconhilltelescopes.org.uk/pricelist.html for an old price list or for contact details go to http://beaconhilltelescopes.org.uk/contact.html

They do custom work as well.

Thank you, their prices seem very reasonable actually. Probably worth dropping them a line, although I do now wonder what else might be wrong with the scope! 😖 It was only £70 used, so not really worth throwing much more money at it. I was hoping it might be a nice G&G scope which is a tad better than the Heritage with its R&P focusser, closed tube and ability to take 2” eyepieces. 

[Second Time Around]

Note that Beacon Hill ask on their website not to email unless urgent but to telephone them.

[Astrobits]

I believe that Barry Watts ( Beacon Hill Telescopes ) has effectively retired but might be able to help if you phone. Note that the price list on his web site is dated 2010, 14 years ago.

Nigel

[Second Time Around]

I spoke to him this morning - he's still going strong and working at 82.  It's just the website that hasn't been updated.

[Astrobits]

That's great to know.  

Nigel 

[RobertI]

Just to complete this thread, I ended up bending two of the vane flanges by 180 degrees using a vice, pliers and a wooden mallet! All four vanes now line up nicely. The scope is now collimated and ready for a night’s observing. 

[Second Time Around]

Barry at Beacon Hill Telescopes has just made me a secondary support for my 10 inch.  I'm very pleased indeed with it.

I had it made with 4 knurled screws as this makes it easier to adjust than using 3.

Edited August 20 by Second Time Around

[PeterStudz]

1 hour ago, Second Time Around said:

Barry at Beacon Hill Telescopes has just made me a secondary support for my 10 inch.  I'm very pleased indeed with it.

I had it make with 4 knurled screws as this makes it easier to adjust than using 3.

This is interesting and good to know! I wasn’t even sure that Beacon Hill are still active.

[woldsman]

If you need a part, I think I still have a spider taken off a 130 pds that might fit your scope. If you'd like to have it, PM me with your address. 

It's back home - I can look for it at the weekend. 

 

[RobertI]

1 hour ago, woldsman said:

If you need a part, I think I still have a spider taken off a 130 pds that might fit your scope. If you'd like to have it, PM me with your address. 

It's back home - I can look for it at the weekend. 

 

That’s really very kind of you - I will PM you.  

[RobertI]

Further question on this scope. It’s possible to remove the 1.25” fitting to reveal a supposedly 2” fitting - but it’s not 2” - I tried putting my 2” Panaview in and there’s a gap of several mm. It seems to be 56.9mm diameter. Any idea of what fitting this is and how I would convert it to 2”?

[RobertI]

17 hours ago, RobertI said:

Further question on this scope. It’s possible to remove the 1.25” fitting to reveal a supposedly 2” fitting - but it’s not 2” - I tried putting my 2” Panaview in and there’s a gap of several mm. It seems to be 56.9mm diameter. Any idea of what fitting this is and how I would convert it to 2”?

Ah, it appears I need one of these…. http://skywatcher.com/product/2-eyepiece-holder-for-dob-57mm/  Not sure how well 2” eyepieces will work anyway, but it would be nice to try….

Edited August 27 by RobertI

[RobertI]

I have now received the replacement spider from a 130PDS as donated by the very generous @woldsman , who also dispatched it at his own cost - what an amazing gesture! Thank you @woldsman.   It appears to fit fine so I shall post a pic when fitted. I’m now thinking that I might as well flock the inside of the tube while I’m at it. Oh, and I need to reposition the secondary mirror centrally on its holder (see original post above). I’m now determined to make this a high performing scope! 
 

Edited August 27 by RobertI

[CraigT82]

1 hour ago, RobertI said:

I have now received the replacement spider from a 130PDS as donated by the very generous @woldsman , who also dispatched it at his own cost - what an amazing gesture! Thank you @woldsman.   It appears to fit fine so I shall post a pic when fitted. I’m now thinking that I might as well flock the inside of the tube while I’m at it. Oh, and I need to reposition the secondary mirror centrally on its holder (see original post above). I’m now determined to make this a high performing scope! 
 

That is a very nice gesture and score +1 for the SGL community ✔️

The secondary mirror is supposed to be like that though, it's called offset and the faster the scope the large the required offset. The measured offset is the distance in blue in this image, it can be calculated pretty easily...

 

https://skyandtelescope.org/astronomy-equipment/offsetting-your-secondary-mirror/

 

 

 

 

[RobertI]

55 minutes ago, CraigT82 said:

That is a very nice gesture and score +1 for the SGL community ✔️

The secondary mirror is supposed to be like that though, it's called offset and the faster the scope the large the required offset. The measured offset is the distance in blue in this image, it can be calculated pretty easily...

 

https://skyandtelescope.org/astronomy-equipment/offsetting-your-secondary-mirror/

 

 

 

 

Thanks for the info, that’s just what I was after. I recalled something about offset, but assumed in this case it was another “defect” of the scope. I read the article, but it hasn’t really clicked yet, I’ll try and get my head around it. 

[woldsman]

8 hours ago, RobertI said:

I have now received the replacement spider from a 130PDS as donated by the very generous @woldsman , who also dispatched it at his own cost - what an amazing gesture! Thank you @woldsman.   It appears to fit fine so I shall post a pic when fitted. I’m now thinking that I might as well flock the inside of the tube while I’m at it. Oh, and I need to reposition the secondary mirror centrally on its holder (see original post above). I’m now determined to make this a high performing scope! 
 

Glad it arrived safely & hope it does the job. We agreed you’d put a fiver in the RNLI collection box - a great charity that saves lives along the East Coast (close to me) & the rest of the UK. Plus folks on this site have helped me out several times.

Edited August 27 by woldsman

[RobertI]

57 minutes ago, woldsman said:

We agreed you’d put a fiver in the RNLI collection box - a great charity that saves lives along the East Coast (close to me) & the rest of the UK. Plus folks on this site have helped me out several times.

Donation made as agreed - actually much easier to do via their website in the end. Thanks again, it was really your donation, not mine. As you say, a great charity and often under appreciated emergency service. My mother’s side of the family has a long history with the lifeboat, her uncle and grandfather both being coxswains of the Walton and Frinton lifeboat and various other family members being lifeboat crew over the years. Makes me feel rather ashamed at how much of a landlubber I am!

[RobertI]

I’ve now fitted the new spider, blackened the edges of the secondary while I was at it, collimated and finally reunited the scope with a SkyProdigy mount. Might be clear tonight so looking forward to having a little session.