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Which 13" Dovetail Mounting Bar is stiffer?

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#1 clydet

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Posted 29 January 2010 - 11:40 PM

Celestron's or Orion's
Does anybody know which 13" Dovetail Mounting Bar is stiffer? :confused:

#2 BlueGrass

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Posted 30 January 2010 - 12:14 AM

Clyde,
Both are pretty stiff.. what is the basis for your question? Are you thinking about flexure? What is the OTA you're looking to mount?

#3 clydet

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Posted 30 January 2010 - 02:21 AM

Yes, about flexture.
The OTA is a Celestron C10N.
It's about 30 pounds.

#4 wormstar

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Posted 30 January 2010 - 07:22 AM

both Celestron bars I had (Losmandy and Vixen style) for a C9.25 were extruded Aluminum. An actual Losmandy bar is solid aluminum, Robin Casady and BT Tech both have nice machined bars too, but all are pricy compared to the 2 you questioned, but would be much stiffer.

#5 DaveJ

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Posted 30 January 2010 - 07:33 AM

We need to add ADM in this mix. Link
Beautifully machined dovetail bars and other associated equipment in both "D" and "V" sizes.

#6 wormstar

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Posted 30 January 2010 - 09:19 AM

Dave-you are right- the ADM bars are nice, My Tak FS60 is currently living on a short V style ADM bar, cheaper than the ones i listed above. The finish nice, but is flat not glossy anodized like the rest, not sure if this is typical of ADM

#7 mclewis1

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Posted 30 January 2010 - 09:35 AM

I agree about the solid Losmandy V and ADM V bars, they are the most robust I've seen or used. The extruded ones are IMHO more appropriate for lighter scopes (SCTs) or smaller scopes (guide scopes, etc.).

With a big and relatively heavy scope like a C10 I'd seriously consider Losmandy D plates if appropriate (if your mount can handle a D type saddle and you can manage the extra weight). The D plate is even stiffer than the V bars and it's wider surface makes mounting heavy rings even more secure.

With a big scope like the C10 a moving side plate saddle can also make a big difference in how easy it is to mount the scope. A moving side plate saddle allows you to tip in or side load the scope instead of having to slide the bar/plate in from the end of the saddle (which requires more accurate positioning of the scope to get it to slide properly).

#8 BlueGrass

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Posted 30 January 2010 - 10:40 AM

Clyde,

It really depends on what you want to spend. The Orion guidescope bar you asked about in your other post is solid aluminum though and pretty beefy. You may have to countersink the holes on the mount side to allow the bolt heads to sit flush. Good luck.

#9 clydet

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Posted 30 January 2010 - 01:08 PM

BlueGrass,
Do you think the 16.5" Orion guidescope bar would be stiffer than the Orion 13" dovetail mounting bar?

#10 BlueGrass

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Posted 30 January 2010 - 01:51 PM

Clyde,

Based on the pictures on the Orion website, they look to be manufactured out of the same extruded aluminum stock. Just cut and machined differently. I don't have an actual Orion dovetail so I can't be sure. The only advantage of using the guidescope bar is it's pre-drilled to mount rings at a number of various spacings. Good luck with your quest... :jump:






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