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Redcat 51 + EFW Woes

William Optics Redcat 51 Equatorial Mount Troubleshooting
12 replies•253 views
David Ebbecke avatar
David Ebbecke avatar
Does anyone have a setup recommendation for the Redcat 51 + EFW that won't interfere with the tripod/pier extension/azimuth knobs?  I've already bashed into twice now.  Thankfully the AM5 detected the obstruction and stopped slewing before shearing it right off.  I've started using the hand controller to manually slew just to avoid future collisions.  Any help would be greatly appreciated.  BTW, I'm at 55mm back focus with the above setup.  I swap the camera+EFW with my C8, hence the presence of the OAG.
andrea tasselli avatar
andrea tasselli avatar
You need riser block(s) between the mount plate and the scope holder ring.
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Richard avatar
Richard avatar
I'm really surprised that you are balanced in declination with this setup, it looks quite back heavy!

Though it might not be best practice, I find that mounting the filterwheel in the orientation shown in my picture below reduces any obstructions/impacts during slews. No matter the target, I try to keep the rotation this way to avoid any other balancing issues or impacts after meridian flip.

I just noticed that you are using an OAG, which means you are trading one obstruction with another if you follow my suggestion. @andrea tasselli offers a good solution with riser blocks!

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David Ebbecke avatar
David Ebbecke avatar
Thanks Richard.  I'm actually NOT balance in declination which makes for a difficult time with PA.  I looked into riser blocks but wasn't able to locate any for the RC51.  Thanks for the solution!  Regarding the EFW, I would keep it in the position that your illustration shows, but when framing a target, the whole system rotates with the CAA.
David Ebbecke avatar
David Ebbecke avatar
Suggestions for riser blocks that will work with the RC51?  Thanks!
andrea tasselli avatar
andrea tasselli avatar
Frank Szabo avatar
Frank Szabo avatar
If i can just insert that the strainwave mounts do not need to be balanced. Meaning:  not need to balanced in the DEC or RA. They don't care unless it's absolutely grossly overweight on one side with a very large scope like an 8" Celestron.  A Redcat 51 is absolutely nothing to an AM5 mount. 

Beside that point I would try to rotate that filter wheel to a different position, and possibly also use a longer dovetail bar. 

Here is a setup I saw somewhere else
https://www.instagram.com/agenaastro/p/CvFYmOtuBeY/?img_index=1
David Ebbecke avatar
David Ebbecke avatar
Frank Szabo:
If i can just insert that the strainwave mounts do not need to be balanced.

Beside that point I would try to rotate that filter wheel to a different position, and possibly also use a longer dovetail bar. 

Here is a setup I saw somewhere else
https://www.instagram.com/agenaastro/p/CvFYmOtuBeY/?img_index=1

Thanks for the reply, Frank.   Stating I was out of balance in DEC wasn't accurate.  The DEC adjustment on the lags for a lack of a better way to phrase is due to the improper weight distribution.  When more centered on the mount, the adjustment functions w/o the lag.  The longer dovetail didn't seem to solve the problem for me.  I don't know how to maintain the filter wheel in an ideal position if needing to rotate the system for target framing.
David Ebbecke avatar
David Ebbecke avatar
Tony Gondola avatar
Tony Gondola avatar
Don't forget about wood as a material. I have my guide scope mounted on a wood platform and it works fine. You could easily make a riser that way.  Seal it with a few coats of poly and you're on your way.
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Kay Ogetay avatar
Kay Ogetay avatar
I personally never needed such an update, but you may do especially if you use the rotator. I second the riser block. I'm not rotating mine, and the weight balance isn't an issue with the AM5. The EFW is just positioned in a way that it never hits the knobs. If you don't need the rotator, then this might just solve your problem.
Alex Nicholas avatar
Alex Nicholas avatar
You don't need a 'riser block for a Redcat 51" you need a 2x2x2 inch block of aluminum offcut, with holes drilled in it in the right spots, and bolts that are 2" longer than your current bolts to connect the scope/dovetail through the blocks.

People get really carried away with having something that is purpose built for the task they are trying to achieve, when in a lot of cases, a small block of aluminium with some holes drilled in it will do perfectly fine.
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Brian Puhl avatar
Brian Puhl avatar
Turn your filter wheel 180 degrees.

Also that scope is sitting wayy too far back in the saddle.