Re: [RCX400] Re: Focus/Collimation Problems
- Thanks DocI'm sure that Scott Roberts is relieved at you message, BUT it amazes me that Meade does not provide an e-mail address where one can send one's technical queries. A toll free number does not help international owners. Can anyone assist with an e-mail address that follows the correct chain.RegardsJohn
- About a decade ago I measured the compliance of the LX200 classic fork. The compliance was the same for both the 12" and the 10" scopes since all of the compliance is in the bearing/cone assembly and they are the same. The value was 1 1/2 10E-5 meters/Newton. I have estimated the compliance for the new RCX base from the weight (mass) and resonant frequency. It is in the range of 4 to 8 X 10E-6 meters/Newton. That is, the compliance is about half what it was. This means the mount is about twice as stiff. These are very approximate numbers, but definitely indicate that the center bolt has a significant effect on the stiffness (inverse compliance) of the structure.There is no significant compliance in the Super or Mitty wedges. It is no more than 10% of the total compliance of the mount if that much.While I did one time break the base of an LX200 classic, I do not think that would be possible with the RCX base when used with the center bolt. Well, perhaps if you had it polar aligned at the equator and sat on it. (VBG)Doc G----- Original Message -----From: Mark de RegtSent: Friday, November 04, 2005 12:52 PMSubject: RE: [RCX400] Re: Focus/Collimation Problems> Correct! Sorry if this wasn't clear. AstroEngineering (UK)
> insist (and I mean **insist**) that the central bolt is not
> required for stability. I am still not convinced that they
> are correct, but try telling that to AE..... In their design
> the tilt plate is levered up in the centre using a threaded
> rod. It would have to be done differently if decided to do
> what everybody else does.
It may not be required for stability, in the sense that adding the
honking center bolt may not make the rig any more stable.
But it is required for safety. Even in northern latitudes, the
telescope is tilted over a good bit, and it really is held onto the
wedge only with the top bolt if you use only the three outer bolts (the
lower ones would tear out in a heartbeat if the top one gave out). The
RCX400 is heavy, and it has a lot of weight very far from the base.
That's a huge amount of leverage. Ask AstorEngineering (UK) if they
promise to buy you a new RCX400 when your existing one does a face
Mark de Regt
Redmond, Washington, USA