TS Optics / GSO 2" diagonal thumbscrew disaster

[Louis D]

12 hours ago, badhex said:

Whatever they are made of now is a very lightweight, silver-white non-magnetic metal, possibly aluminium. 

Generally pot metal is majority zinc.  That's what we're dealing with here.  Metals alloyed with it can include lead, tin, aluminium, and copper.  There is no standard for it.  In all cases, it has a low melting point and a porous, brittle structure.  Based on the images below of a broken SkyTee-2 mount, they're also cast from pot metal:

I'm sticking with mounts machined from solid billets of aluminum like my DSV-1 and DSV-2B mounts for my scopes.

[Zeta Reticulan]

It seems like it's pot luck with pot metal. 

[badhex]

Agreed. Definitely low quality, although I'm sure I saw somewhere some thumbscrews labelled as GSO and claiming to be aluminium. Perhaps when I've got the replacements, I'll get a torch to one of these and see how easily it melts! 😂

[ED Splitter]

I wonder how many eyepiece holders are shipped with cheap screws. Just think much money is dangling off them. 
Eek. 

[Zeta Reticulan]

46 minutes ago, ED Splitter said:

I wonder how many eyepiece holders are shipped with cheap screws. Just think much money is dangling off them. 
Eek. 

This has always concerned me. I've never had any problems with GSO thumbscrews, although the only GSO diagonals I own are resin-bodied Amicis. 

There are an awful lot of thumbscrews on my GSO focusers though. 

Edited August 2, 2022 by Zeta Reticulan

[SthBohemia]

On 30/07/2022 at 00:49, badhex said:

Definitely low quality,

Through interest grabbed a magnet and tested all thumb screws on astro gear,  all are steel! As I have not purchased anything for at least 2 decades +++ I assume PRICES have increased while QUALITY has declined. Bit of a sad indictment to the manufacturers.

...and after reading the story ^^ I won't be purchasing anything for the next 2 decades++ (Paul Rini and Gary Russell EP's being the exception)

[Mandy D]

Low quality metal parts are becoming more of a problem. I saw a 3 jaw lathe chuck advertised on Amazon, "made from high quality zinc alloy"! You honestly could not make this stuff up!

[Ags]

1 hour ago, Mandy D said:

"made from high quality zinc alloy"

I would have fallen for that line 😆 Good thing I am a programmer not a lathe operator. Although it is usually my type up in head office that buys the "three jaw lathe chucks" (what???) for the unfortunate lathe operators?

[badhex]

It blows my mind that the optical quality and general engineering quality of GSO stuff is very high, and then they save a couple of cents on... screws?

I get that it all adds up, but still. 

[Zeta Reticulan]

46 minutes ago, badhex said:

It blows my mind that the optical quality and general engineering quality of GSO stuff is very high, and then they save a couple of cents on... screws?

I get that it all adds up, but still. 

It wasn't always the way with GSO though. Many moons ago a lot of their stuff was often regarded as a bit cheap and dodgy. Although this isn't really the case now, some of their products are still a bit suspect. 

Case in point: the 3x ED Barlow.

The build quality is pretty decent. However, the element itself suffers badly from chromatic aberration. It's really not suitable for astronomy. I'm not the only person to notice this either, so it's unlikely to be a QC issue. Regarding the thumbscrews, I have no idea where GSO source them from. They are quite distinctive. A few years ago they started to replace their original thumbscrews with the larger 'aluminium' ones. At least I assumed they were aluminium. If they are in fact pot metal I should imagine it was an economic decision. It's a very real possibility the pandemic has disrupted supply lines. 

I've noticed that many SvBony thumbscrews are un-chromed bare brass, as are the spigots on new Vixen mounts. 

A year ago I bought this GSO 20mm Plossl.

Basically my OCD cut in and I wanted to complete the set. I had all of the others. It's a great 20mm Plossl. It's also silver and has an odd eyeguard. GSO made the Celestron Omni Plossls at one time. I wonder if they used an old stock Omni housing for my unusual silver 20mm Plossl? 

Edited August 2, 2022 by Zeta Reticulan

[Louis D]

I bought my used GSO CC over 6 years ago, so it is likely close to a decade old.  It had the pot metal screws that jammed and then sheared off in one of the holes.  I would surmise that the use of these screws greatly predates the pandemic.

[Zeta Reticulan]

Probably.

This is a 31.7mm GSO Amici. I bought it new seven or eight years ago . It has one of the old smaller thumbscrews. It doesn't look like pot metal. It's only comparatively recently GSO have been equipping these Amicis with the larger thumbscrews. I should imagine it was an economic decision.

[SthBohemia]

8 hours ago, Mandy D said:

3 jaw lathe chuck advertised on Amazon, "made from high quality zinc alloy"!

Obviously a special manufactured by, "Mickey Mouse Components Inc". I miss out on seeing the 'hilarious deals' from Amazon as I wouldn't touch the company with a barge pole! As for Asian manufactured lathe components... 😞 

Pity Myford don't make GEM's, the only downside would be the 85Kg weight (for an equivalent of say a SW EQ6)!

[badhex]

5 hours ago, Louis D said:

I bought my used GSO CC over 6 years ago, so it is likely close to a decade old.  It had the pot metal screws that jammed and then sheared off in one of the holes.  I would surmise that the use of these screws greatly predates the pandemic.

My GSO 2" Barlow was purchased over seven years ago (and which I've never had issues with but is not used that often) has the same screws as the diagonal, I think. I would have to compare them side by side to be sure. 

[badhex]

Agenda Astro sell spare GSO screws and lists the material as "Material: Varies based on available stock" 

So, could be anything. 

[Zeta Reticulan]

13 minutes ago, badhex said:

My GSO 2" Barlow was purchased over seven years ago (and which I've never had issues with but is not used that often) has the same screws as the diagonal, I think. I would have to compare them side by side to be sure. 

This Barlow?

The screws look the same.

[Zeta Reticulan]

5 minutes ago, badhex said:

Agenda Astro sell spare GSO screws and lists the material as "Material: Varies based on available stock" 

So, could be anything. 

I think that says it all. Like I said earlier; pot luck lol.

[SthBohemia]

9 hours ago, Zeta Reticulan said:

OK Zeta, after ascertaining you to be both a salesman and a spy, do I now add you as an intrepid collector of astro gear? I have never seen, known or heard of someone with such a huge range of eyepieces, diagonals, barlows etc etc etc as yourself!

Would you please be so kind as to confirm that you are either setting up an exhibit or a museum of astro gear within your Zeta Reticulan spacecraft?

[Zeta Reticulan]

5 hours ago, SthBohemia said:

OK Zeta, after ascertaining you to be both a salesman and a spy, do I now add you as an intrepid collector of astro gear? I have never seen, known or heard of someone with such a huge range of eyepieces, diagonals, barlows etc etc etc as yourself!

Would you please be so kind as to confirm that you are either setting up an exhibit or a museum of astro gear within your Zeta Reticulan spacecraft?

We come in (eye) piece ...

 

[SthBohemia]

4 minutes ago, Zeta Reticulan said:

We come in (eye) piece ...

🙂 🙂 🙂 Gotta admit it- You are GOOD 🙂 

Loved the video....

[Zeta Reticulan]

I wouldn't say I had that many diagonals.

[badhex]

7 hours ago, Zeta Reticulan said:

This Barlow?

The screws look the same.

Yes, same one. I suspect that they are the same, certainly the same form/shape. I feel like the diagonal ones are more of silver-white than explicitly silver. My diagonal is packed away in my travel kit so need to check.

[Zeta Reticulan]

57 minutes ago, badhex said:

Yes, same one. I suspect that they are the same, certainly the same form/shape. I feel like the diagonal ones are more of silver-white than explicitly silver. My diagonal is packed away in my travel kit so need to check.

I've never had a GSO thumbscrew fail, but I did change the GSO screw I'd put on my Synta 2" dielectric back to another non-GSO screw. I quite liked the new GSO screws, until I read this thread. 🤯

[SthBohemia]

1 hour ago, badhex said:

his Barlow?

Why do members astro bits and pieces look so shiny and new, and mine resemble something one of the cats dragged in? A scope even has some hardened fibreglass resin I accidentallyl spilt on it 🙂  Maybe I am simply grubby?

[teoria_del_big_bang]

57 minutes ago, SthBohemia said:

Why do members astro bits and pieces look so shiny and new, and mine resemble something one of the cats dragged in? A scope even has some hardened fibreglass resin I accidentallyl spilt on it 🙂  Maybe I am simply grubby?

We just Photoshop the images, way of the world these days 🤣

Steve