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Dovetail plates and saddles advice for Mach 1?

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#1 Doug D.

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Posted 27 March 2009 - 09:02 AM

I'm trying to "dress" my soon to arrive Mach 1 and also streamline/reduce the nightmare of different plates and saddles I've accumulated to mount different scopes on different mounts over the years. One of my plans is to now "standardize" things a bit by going with 13.5" Losmandy plates for my 105 and 140 (and retiring my DOVE08).

I realize an 8" saddle (such as the one AP sells) will handle the 13.5" and give me room to slide things back and forth for balance. However, I want to eliminate the possibility of flexure as much as possible (esp. with the 140 beast) and a 12" Robin Casady seems like it might be ideal in this regard (AP makes an 8 & 16 but no 12). I'll certainly have room to slide the OTA within the rings and it looks like the Casady plate can also be mounted off-center to help with balance if necessary.

So - any thoughts? Would I be making a mistake going with a 12" saddle or am I just making too much of this? Hard to imagine that a 13.5" plate is going to flex much in an 8" saddle.

BTW, I already own 3 8" Casady saddles (used in a tandem bar arrangement) so I don't plan to buy another 8" in any event so I guess I could always swap out the 12" saddle for some set-ups. My impression is that the Casady saddles are a little nicer and beefier than APs - would anyone disagree with that claim?

#2 LLEEGE

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Posted 27 March 2009 - 09:40 AM

I have been using my 140 with the 8" AP saddle.

#3 RAKing

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Posted 27 March 2009 - 09:51 AM

Doug,

I have a 12 inch Casady saddle and it's a great piece of gear. It can be offset, if needed.

I cannot imagine you needing anything longer than an 8 inch for your scope. A 13 inch dovetail is going to have little overhang and I just don't see a 140 causing that to flex.

But if you want to swap for one of your 8 inchers, let me know. :lol:

My .02,

Ron

#4 Doug D.

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Posted 28 March 2009 - 06:28 PM

Thanks Luke and Ron - I will get the mount with the AP 8" saddle and use it with the 13.5" plates.

Ron, I might take you up on that offer to trade the 8 Casady for your 12, but I'll try living with the 8 for a while and see what I think.... BTW, which part of cloudsville VA do you live in? I'm in cloudsville/c'ville and man, hasn't that been the truth for the past couple of weeks !!??

#5 DeanS

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Posted 28 March 2009 - 08:34 PM

12" cassady on both my Mach1 and 1200. I like that they are both tilt in aswell.

#6 RAKing

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Posted 29 March 2009 - 07:39 AM

Doug,

I'm up in Gainesville. This month started off great, but has been terrible since. I feel sorry for the Messier Marathon guys in my club. This is the second year in a row they have been defeated by weather. :(

I have downsized my scopes and could get by with the 8 incher, but I prefer the Casady saddle over anything else and will keep it for now. :cool:

Ron

#7 Doug D.

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Posted 29 March 2009 - 09:05 AM

12" cassady on both my Mach1 and 1200. I like that they are both tilt in aswell.


I've not seen an AP saddle for Losmandy D series - I assume it is tilt in as well, no? My DOVE8 is tilt in for sliding bars. Or maybe "drop in" is a better description.

#8 mnaf

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Posted 30 March 2009 - 11:39 AM

I'll chime in, although it appears you've made your decision. I was faced with the same question - what saddle to use on the arriving Mach1. I'm starting from scratch w/o exisitng plates so I chose AP's new DOVELM162. With a 13.5" plate there's not much if any sliding room for balance, however, the saddle offers a varitey of mounting positions to compensate. It's remarkably light - I think lighter than the 14" DMM I plan to use for short f/l scopes! It might even work with a 7" plate with one clamp tightened (with a hex). I plan to use it with a 24" plate for a reflector, too.

I was worried about flex as well - a call to the great folks at AP convinced me that the 16" saddle was best for my reflector and a 14" DMM with Los. clamps should work well for refractors.
And..it's a really beautiful piece of work! :)

My 2 cents...

P.S. It's tilt-in as well and it uses wide blocks to clamp the plates as opposed to the 8"'s pins. I'm not familiar w/ Cassidy saddles...

#9 LLEEGE

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Posted 30 March 2009 - 11:44 AM

The AP 8" is a tip in.

#10 NHRob

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Posted 30 March 2009 - 01:33 PM

Hmmm ... similar question for me ... I have a TEC140 coming, to mount on an altaz. I could go either the AP Dove8 direction or a Cassidy saddle. Is there any difference in rigidity/stability?

Thanks,
Rob

#11 Doug D.

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Posted 30 March 2009 - 05:34 PM

I have 3 Casady 8" saddles, they are very nice and certainly up to AP standards. I must confess though, I'm not as thrilled with the idea of the brass pins (as opposed to a clamp) on the AP version. I do have a DOVE8 for the 7" AP sliding bar which uses an "angled" brass pin and I must admit it works just fine.

The individual clamps on the Casady dovetail have 2 steel guide pins each, captive knobs and are "springed" - all nice touches, IMO.

The Casady 8" is more expensive than the AP version.

#12 Tom and Beth

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Posted 30 March 2009 - 08:55 PM

If this helps, I have the AP 8 inch on my AP600, all of which handles my TEC 140 with no problems, and I've piggybacked a TV76. The pins work very well, and the tip in feature is smooth and effortless.

The only difference is that I'm using the TEC 12 inch plates (Losmandy compatable).

Tom






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