Re: AP1100, Berlebach Planet, mounting CP4

Woody Schlom

I just remove the RAPAS after PA.  Cables want to hang up on it anyway.


On July 28, 2021 8:08:13 PM "ap@..." <ap@...> wrote:

This is an old topic but now that I know how it works, I thought I would put some closure to it.

I got the AP1100, and it worked, first try, out of the box - no issues at all.  Ethernet connection, drivers worked, NINA connected to it, all good.  Now that's indoors as weather is not good but of three prior mounts this was by FAR the simplest to get working out of the boxes.


The mating with the Planet was not so easy.  If you look at the photo on the first posting in this thread, it has the Berlebach custom AP1100 base.  It fits perfectly, in terms of the circular base, and all the holes line up, but... 

The screws from AP are WAY too short, or more precisely the thickness of the Berlebach base must be at a lot thicker, the screws will not even reach the holes. Trip to the hardware store mostly fixed it (had to get hex head not socket, but have some socket heads on order). 

This thickness also throws off the CP4 mount, especially since a screw hole hits exactly in the middle of the CP4 mount.  Basically you can't get the mount plate close enough to the mount base as the tripod base is too thick.  Leaving the screw (one of 6) out lets you mount it but it still is not flat -- I've got longer screws on order and some plastic spacers. 

But bottom line -- the custom Berlebach base is massively heavy duty and well built, but causes some (fixable) issues when you go to put it together.  Berlebach could fix that with a couple dollars worth of hardware accompanying the base.  It almost seems like they never actually tried it.


The really good news is that the AP1100 is quite a bit larger than my MyT and positioned differently, and so I ended up with quite a bit more leg clearance -- my guess is I could go about an hour past transit without a leg crash.

The other aspect of this news is this: on the MyT I had more leg clearance with the counterweight between two legs, not over a leg.  It also was closer to the center of the tripod, and this did not cause an issue while loading counterweights.  On the AP1100 I can't mount it that way, it hangs out too far, when loading counterweights I think it would tip over (it's fine with it over the North leg).  But this became moot because the same over-hang also provided a lot more clearance, so there was no need to mount it backwards -- plenty of room in the standard configuration.  Lots of room.

Still got a lot to do, but it's going to work fine, with a bit of accomodation. 

Oh... one more issue not tripod related (below) 

There was one surprise -- my refractor doesn't clear the RAPAS over quite a bit of its rotation angle.  When balanced the OAG lands directly over it.  Sideways it's fine, but either camera down, or certainly filterwheel down, it's a problem.

I'm going to get taller standoffs for the rings to raise it up.  I may also decide to put front weights on the dovetail so I can slide the OTA further back, but that just brings back some of the leg crash issues, so I think raising the OTA will at least solve the camera direction.  I can live with keeping the filter wheel not down, there's still about 270 degrees of rotation that won't hit.  I guess back weights and sliding forward is possible also, but no good place to mount those.

Anyway.... while some integration pains, I can't tell you how pleased I am that it all just came together and worked as soon as I fired up the software.

C11 sizing tomorrow, but I think that one is easier, as it is naturally taller. 

Now if only there was some clear skies. 


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