Is this a silly idea?

[MG1]

...and if not would it be expensive?

I've been thinking a little bit about how my scope attaches and alternatives the the altair astro clamp I have at the moment.

But then I noticed that our setup is pretty much always the same and I can get balance with the dovetail and tube rings pretty much centred, so I thought what if I did this and simply have a 15mm Ali plate bolted directly to the Altair puck?

The rings could then attach direct, or maybe have an adjustable stainless steel plate that could be tweaked with the orange thumbscrews to adjust for Cone Error?

Would it work? and if so, any suggestions of how I might go about getting it made...just the plate and the stainless inserts needed as I have the rings and the puck.

...or maybe it's a stupid idea?!?!

ps...go easy regarding the lack of engineering details...no education in that department!

[datman]

Hi

Not sure why you are doing this, is it just to avoid balancing the scope end to end and have an adjustment for cone error?

Which Altair Astro system do you have and also what sort of telescope are you trying to set up?

[MG1]

Hi, currently we have a Altair Heavy Duty Saddle bolted to the compatible puck into which is clamped a 12" WO diagonal. The scope rings are attached to the diagonal.

A while back we we running a dual side by side rig, but now we've gone for an OAG we are looking to shed some weight and have minimal connections.

Scope is the 132 in sig. Which is fairly heavy all in with field flattener, filter wheel and DSLR.

The existing rings (simplified in the drawing) give enough lateral movement for balancing scope front to back so there seems little point in the saddle.

I wasn't really satisfied that a couple of grub screws wouldn't introduce another flex point so figured this might be more robust.

But like I said....may just be a silly idea.

I found a place online that sells offcuts and they seem to have some 15mm Al in approx right dims for about £15, so now I just need to find a machinist in Bristol I guess.

[datman]

Hi

Well the idea is only as silly as you think it is! I've made numerous bits and pieces that suit me but others may not see an point in making them.

From a machinist's point of view the work on the plate is not very difficult. So if you are paying someone it all depends on their hourly rate!

Need to make sure the recess doesn't take too much metal away.

[MG1]

Cheers, I was thinking a 15mm plate reduced to 10mm? ADM Los plates are 12.7mm thick so I reckon that should be okay, Then 4mm for the stainless plates.

Was looking here for materials: Sheet Metal Store UK, Ireland, Scotland

& here: Aluminium Plate - Cut to Order - Aluminium Supplier | Aluminium Stock | Aluminium Warehouse

[datman]

Hi

Well I don't think I can help with comments about what you are trying to do but here is another source of metal (I have not used them so this is not a recommendation) but prices look ok.

I think I'd find a machine shop first, they may have what you need to hand.

[Merlin66]

Help me understand....

What's the benefits of your suggestion v's say a Losmandy dovetail/ puck and fixed tube rings????

[MG1]

The only real difference is the adjustability for cone error.

I believe some people drill and tap for a couple of grub screws either end of a losmandy dovetail, I'm just adding a stainless plate that the screws can push against. Mainly because I can see them cutting into the bottom of the tube rings.

And I don't need the losmandy profile because the plate is attached directly to a puck rather than being clamped in a mounting saddle. This should make it lighter.

I'm not saying its without its disadvantages though. It's less flexible than a saddle mount, couldn't easily take other minting options etc, but I don't need that as I'm one tube OAGing for the foreseeable future.

Plus unless machining is really expensive, this could be quite cheap. Whereas a quality losmandy plate is around £50 plus will still need drilling and tapping for cone error screws.

What I'm looking for is a way to adjust for cone error that provides a more stable end situation than aluminium tube rings being clamped down against steel grub screws.... This is just mk i so am happy for suggestions.

Thanks though...hope that clarifies a little.

[Merlin66]

OK for cone error correction I can see some merit......