Are my tube rings mounted properly?

[ste7e]

Hi

I've just moved my SW 130P from an EQ2 mount to a HEQ5 mount.  I'm not sure that the tube rings are sitting right on the dovetail bar.  They just seem to sit on the outer rails - doesn't feel a secure mounting.

Is this as it should be?

 

[brantuk]

I've come across this before and thought it was a bit strange. I would much prefer a flat dovetail bar for the rings in your picture above. I've always thought the "ridged" dovetails were meant for mounting straight onto curved surfaces - ie the scope main tube. I guess so long as it's secure it's ok - but I'd always rather have the right tool for the job.

[ste7e]

Yeah, that's what I thought, too. 

[swag72]

Personally I'd be changing that dovetail for a flat one such as this ADM version https://www.firstlightoptics.com/dovetail-bars/adm-vixen-style-universal-dovetail-bars.html - That way the rings will be in contact across the dovetail.

[DaveS]

Agreed.

Your photo shows how they "should" look but it's not good engineering. I'd be swapping it for an ADM version pronto.

I'd also be swapping out the Skywatcher puck for an ADM one, also from FLO.

[iapa]

This is how my dovetail fits.

My guess is that these are designed to be attached directly to the tube - such as SCTs and the ilk which are often predrilled.

I will be moving the different dovetails for the 200mm at some point. It does seem to be perfectly secure tho.

[ste7e]

1 hour ago, swag72 said:

Personally I'd be changing that dovetail for a flat one such as this ADM version https://www.firstlightoptics.com/dovetail-bars/adm-vixen-style-universal-dovetail-bars.html - That way the rings will be in contact across the dovetail.

More money... don't you just love this hobby?!

[ste7e]

1 hour ago, DaveS said:

Agreed.

Your photo shows how they "should" look but it's not good engineering. I'd be swapping it for an ADM version pronto.

I'd also be swapping out the Skywatcher puck for an ADM one, also from FLO.

OK, I'm prepared to show my ignorance.  Which bit is the puck?

[Davey-T]

You can just file it flat.

Dave

[DaveS]

It's the bit on top of the dec axis that the dovetail goes into. The SW one is horrible and will dig gouges out of you dovetail.

This is what you want:

https://www.firstlightoptics.com/adm-replacement-saddles/adm-dual-saddle-upgrade-for-heq5-neq6-avx-zeq-ioptron.html

[ste7e]

7 minutes ago, DaveS said:

It's the bit on top of the dec axis that the dovetail goes into. The SW one is horrible and will dig gouges out of you dovetail.

This is what you want:

https://www.firstlightoptics.com/adm-replacement-saddles/adm-dual-saddle-upgrade-for-heq5-neq6-avx-zeq-ioptron.html

Right, I see.  Thanks for that.  The mechanism on that one looks much better as it grips all the way along.  I might have to wait a while for that though - my wallet is already bruised by the EQ2 -> HEQ5 upgrade

[LukeSkywatcher]

I noticed the same issue on monday when i mounted my little 70mm refractor onto my 8115 tripod. The scope itself doesnt have tube rings, just a base "foot" plate that screws onto any camera tripod via a quick release plate on the tripod. I'd never noticed it before and thought it looked very strange. It also caused a bit of a wobble which i have never noticed before either. 

[Starlight 1]

8 hours ago, ste7e said:

Hi

I've just moved my SW 130P from an EQ2 mount to a HEQ5 mount.  I'm not sure that the tube rings are sitting right on the dovetail bar.  They just seem to sit on the outer rails - doesn't feel a secure mounting.

Is this as it should be?

 

Each side of bolt you have 2 allan bolts  and with the center one  is the locking one when doing Cone error   so its why its not flat.

[Owmuchonomy]

I agree. When using the cone error adjustment the dovetail profile becomes redundant with the SW models. If you own an AZEQ6 like me it becomes an important factor for dual scope alignment.

[ste7e]

14 hours ago, Starlight 1 said:

Each side of bolt you have 2 allan bolts  and with the center one  is the locking one when doing Cone error   so its why its not flat.

Ahhhhhh... I see.  I just removed those allen bolts thinking they were for some other type of tube rings.  I haven't got around to looking at cone error yet - still feeling my way into this. 

Thank the stars for SGL!

[Sirius Starwatcher]

Glad you got it fixed Steve a final check to make now to prove its all in the right place,  if your eyes have stopped watering you know the tube rings are in the right place!

[ste7e]

Ouch

[RT65CB-SWL]

If you are 'worried' about the tube ring mount bolts coming loose, you could add a drop of 'thread-lock' liquid to the bolt threads. In fact I have applied it to the bolt threads that attach the dovetail bars on my C6 SLT and TV Ranger OTA's. No fear of them 'ever' coming loose!