A question on the weight capacity regarding mounts.

[Vanilla]

I suppose what brought this to my mind is: A friend of mine has a ZEQ25 with 2" steel tripod legs. He has about 48 lbs or 21.77 Kilograms on the mount (Vixen type). He's had this setup for months and it works flawlessly and tracks great.

I asked him about all that weight and he said: "Look, the main bearing on this thing would probably hold 100 pounds easily plus I have it perfectly balanced so there's no severe drag on the gears"

I'm a little confused...is he right or is he looking for a major failure in the coming months/years ??

PS: I was going to get an ioptron mount that holds 35 pounds but why should I spend a lot more cash if I don't need to..

[oldpink]

my mount is overloaded for its AP Spec but works well
having a good balance helps a lot but you can only push it so far
think it was Olly that posted a pic of a HEQ6 with at least 30kg of counterbalance weights on it

think the moral is the better the balance the more you can push it (within reason) past the specified limit

[ronin]

I suppose what brought this to my mind is: A friend of mine has a ZEQ25 with 2" steel tripod legs. He has about 48 lbs or 21.77 Kilograms on the mount (Vixen type). He's had this setup for months and it works flawlessly and tracks great.

I asked him about all that weight and he said: "Look, the main bearing on this thing would probably hold 100 pounds easily plus I have it perfectly balanced so there's no severe drag on the gears"

I'm a little confused...is he right or is he looking for a major failure in the coming months/years ??

PS: I was going to get an ioptron mount that holds 35 pounds but why should I spend a lot more cash if I don't need to..

If it didn't track well would he actually admit that he has overloaded it?

The other question is would it be more accurate if he reduced the load?

The main bearing probably can take a hell of a lot, whether or not the drive chain and motors can is a different question.

Also a perfect balance is not actually what is considered best, means the scope can "rock" a bit. It should be slightly off balance so the scope weight maintains slight weight in one direction.

[Lonestar70]

With the greatest of respect to you and your friend... I would say he is heading for an early failure of his motor drive system... and possibly a warranty failure should he need to make a claim. (gross overload)  

The load capacity of the main bearings has little to do with how much a mount can actually carry in operation.

The ZEQ25 is rated at 27lb max capacity... for astrophotography I would suggest a max of 15 - 16lb.

Overloading it with 48lb (however well balanced) will put a great strain on the motors, motor drivers and drive train in both starting and stopping this amount of weight (inertia).

Add in the fact, as stated by Ronin, that the mount should be slightly imbalanced to ensure a steady load on the gear train, then this will add additional strain. 

If your scope etc is greater than 15 - 16lb all up weight then go for the larger mount.

Hope this helps.

Best regards.

Sandy.

[Vanilla]

Great answers!...I learned a lot. Thanks!

[laser_jock99]

It would be hard to damage the motors/gears if the mount is well balanced- they are not under any particular strain by virtue of the balance. What will instantly damage the drivetrain  is bringing the whole caboodle to a sudden halt during a fast slew (this could be easliy done by pressing 'cancel' on the handset or pulling the power lead out etc). The mechanical inertia of the counterweights and scope will strip the teeth off the worm & wheel if you're not careful. For this reason alone I wouldn't overload a mount that is still in warranty because it will be quite clear to vendor what has happened and the warranty will be void.

However, if you have an older mount to play with then by all means experiment with load capacity- they can actually take quite a lot.

My old EQ6 has been running without complaint for more than 2 years with 70kg (total load) on it -don't try this at home kids....

[Merlin66]

I use a C11 plus all the usual gear on an NEQ6pro mount... three cameras, spectroscope, electronic finder etc. etc.

I figure around 18Kg or so.

Needs five counterweights (25Kg) to get "good" balance.

Certainly the shorter SCT scope helps, but it's been giving great service for the past five years - no issues, no drama.

[Kirscovitch]

It would be hard to damage the motors/gears if the mount is well balanced- they are not under any particular strain by virtue of the balance. What will instantly damage the drivetrain  is bringing the whole caboodle to a sudden halt during a fast slew (this could be easliy done by pressing 'cancel' on the handset or pulling the power lead out etc). The mechanical inertia of the counterweights and scope will strip the teeth off the worm & wheel if you're not careful. For this reason alone I wouldn't overload a mount that is still in warranty because it will be quite clear to vendor what has happened and the warranty will be void.

However, if you have an older mount to play with then by all means experiment with load capacity- they can actually take quite a lot.

My old EQ6 has been running without complaint for more than 2 years with 70kg (total load) on it -don't try this at home kids....

HOLY COUNTERWEIGHTS! 

[ollypenrice]

I don't remember imaging a heavily overloaded mount but I think Laser Jock has the record! But if it works...

My experience of the iEQ45 is that the weak link is the spring loading of the worms into mesh with the wheel. I found that over time this spring loading seems to weaken. What the mount I've used does not like is a physically long OTA. So this is not a mount I would want to overload.

Olly

[oldpink]

yeah sorry Olly it was Laser Jockey that posted it

[Owmuchonomy]

It would be hard to damage the motors/gears if the mount is well balanced- they are not under any particular strain by virtue of the balance. What will instantly damage the drivetrain  is bringing the whole caboodle to a sudden halt during a fast slew (this could be easliy done by pressing 'cancel' on the handset or pulling the power lead out etc). The mechanical inertia of the counterweights and scope will strip the teeth off the worm & wheel if you're not careful. For this reason alone I wouldn't overload a mount that is still in warranty because it will be quite clear to vendor what has happened and the warranty will be void.

However, if you have an older mount to play with then by all means experiment with load capacity- they can actually take quite a lot.

My old EQ6 has been running without complaint for more than 2 years with 70kg (total load) on it -don't try this at home kids....

Anti theft device in operation....;-)