
Edmund's mount questions...
Started by
Raven911
, Nov 18 2006 06:39 PM
5 replies to this topic
#1
Posted 18 November 2006 - 06:39 PM
I have an old Edmund's EQ mount that I know very little about. It is one of the larger ones made for the 8" F8 scopes. It is rather huge, and has 1 1/2" shafts. Does anyone on this forum know anything about this mount? What is it's capacity?
It has a small RA tracking motor and worm gear drive, but I cannot figure out how to use it properly. It appears to clutch in and out with a small removable cylinder lock. However, it appears fixed to the shaft and not adjustable except to clutch it in and out at a fixed position. Is there something I have to loosen to be able to spin it on the shaft to set it?
It has a small RA tracking motor and worm gear drive, but I cannot figure out how to use it properly. It appears to clutch in and out with a small removable cylinder lock. However, it appears fixed to the shaft and not adjustable except to clutch it in and out at a fixed position. Is there something I have to loosen to be able to spin it on the shaft to set it?
#2
Posted 20 November 2006 - 07:33 AM
Post photo's of the mount and you will likely get more reply's...
#3
Posted 24 November 2006 - 01:43 PM
I have the Edmund 6" version, 1" shafts, bought back in 1970. I can pass on some maintenance experience I've had if you're interested. That is one tough mount - it easily carries my 6" f/10 refractor. The clock drive is a little small for my liking, 3" gear, but I spent almost a whole weekend lapping the worm to the gear in my drill press with red rouge and 3 and 1 oil, and it actually tracks pretty well.
Agree - post a picture with closeups. A word is always less than a millipicture.
Mike
Agree - post a picture with closeups. A word is always less than a millipicture.

Mike
#5
Posted 26 November 2006 - 11:14 PM
Sweet! Looks just like mine, except bigger. Good to see you still have your setting circles - mine have long since fractured and vanished.
My RA drive has a small lever that pivots between pins on the drive and allows coarse manual east-west adjustment. Might have looked good on paper to some non-practical ME weenie at Edmund at one time, but it's basically a stupid idea, terribly machined, and a constant source of RA slop. The little drive tracks at the right rate but is just too small for a mount that size. I shimmed the slop out of the lever and was able to do some nice astrophotography with it. But it just can't handle any sizable telescope load unless the balance is perfect and there's no wind.
As far as the mount weight capacity, you've got a nice, massive equatorial mount that can easily carry a 10" scope. But your clock drive will likely be the limiting factor on weight capacity, not mount structure. You might want to talk to Byers or Mathis for a new RA drive that will fit the shaft.
Questions answered, or at least discussed?
Anytime you want to dump that mount, think of me, I love those old Edmund mounts
Mike
My RA drive has a small lever that pivots between pins on the drive and allows coarse manual east-west adjustment. Might have looked good on paper to some non-practical ME weenie at Edmund at one time, but it's basically a stupid idea, terribly machined, and a constant source of RA slop. The little drive tracks at the right rate but is just too small for a mount that size. I shimmed the slop out of the lever and was able to do some nice astrophotography with it. But it just can't handle any sizable telescope load unless the balance is perfect and there's no wind.
As far as the mount weight capacity, you've got a nice, massive equatorial mount that can easily carry a 10" scope. But your clock drive will likely be the limiting factor on weight capacity, not mount structure. You might want to talk to Byers or Mathis for a new RA drive that will fit the shaft.
Questions answered, or at least discussed?
Anytime you want to dump that mount, think of me, I love those old Edmund mounts

Mike
#6
Posted 27 November 2006 - 09:06 AM
I don't know if I will be dumping it soon. I just need to find a more or less permanent spot for it. I use the scope on it for planetary imaging, and would like to get the drive operational.
I can't say I have ever seen any other mounts like it before. I have seen lots of fork mounts and smaller Edmund GEMS, but never any this big.
I can't say I have ever seen any other mounts like it before. I have seen lots of fork mounts and smaller Edmund GEMS, but never any this big.