c14 and a EQ6 - Page 2

Merlin66 (Ken) · #21 26-02-2011, 03:04 AM

Hmmmm
Well, you learn something new each day!
I never knew there was such a lump of metal in the back of my 12" Lx200.......

Tandum (Robin) · #22 26-02-2011, 03:37 AM

WoW it really does look like a 5Kg counter weight. I guess it is ...

Kal (Andrew) · #23 26-02-2011, 02:24 PM

How strange - I never knew there was a counterweight in the back of the meade SCT's either. I would have assumed that the mirror plus all accessories would add enough weight in the back. I have a C11 and I know when I balance it I have to put it almost all the way forward on the dovetail.

I assume this counterweight is only in the LX fork mounted systems, or is it in the OTA's that are purchased seperately as well?

renormalised (Carl) · #24 26-02-2011, 03:28 PM

I think we can safely assume that all Meade SCT's have this counterweight.

Merlin66 (Ken) · #25 26-02-2011, 04:53 PM

Could certainly answer the question as to why the 12" Lx is sooooo much heavier than the Celestron 11"

robz (Robert) · #26 26-02-2011, 05:32 PM

Quote:

Originally Posted by Kal

How strange - I never knew there was a counterweight in the back of the meade SCT's either. I would have assumed that the mirror plus all accessories would add enough weight in the back. I have a C11 and I know when I balance it I have to put it almost all the way forward on the dovetail.

I assume this counterweight is only in the LX fork mounted systems, or is it in the OTA's that are purchased seperately as well?

Hi Andrew.
Could this weight be more beneficial than detrimental?
By that I mean the position of the tube/dovetail and center of gravity?
Would be useful on G.E.M.'s possibly?

Merlin66 (Ken) · #27 26-02-2011, 06:08 PM

IMHO no not really - it just adds weight which is unecessary - the OTA as mentioned could be slid along the dovetail to achieve balance without this extra weight.
It just puts an extra load onto the mount....Hmmm

toc (Tim) · #28 26-02-2011, 06:33 PM

Quote:

Originally Posted by robz

Hi Andrew.
Could this weight be more beneficial than detrimental?
By that I mean the position of the tube/dovetail and center of gravity?
Would be useful on G.E.M.'s possibly?

Im no expert, but I dont see how. Surely most of the weight is going to be in the mirror anyway

Kal (Andrew) · #29 28-02-2011, 07:57 AM

I'd imagine a big counterweight in the back to be a big heat soak that will only lengthen any cool time of the mirror

Kal (Andrew) · #30 28-02-2011, 08:02 AM

Quote:

Originally Posted by robz

Hi Andrew.
Could this weight be more beneficial than detrimental?
By that I mean the position of the tube/dovetail and center of gravity?
Would be useful on G.E.M.'s possibly?

As I mentioned, I have a C11 (which doesn't have a counterweight as far as I know) and I already have to position the scope all the way forward on my GEM because there is so much weight at the back of the scope. If anything I'd need a counterweight at the very light front end of the scope. I'd imagine for a fork mounted sytem where you want the pivot point to be close to the back of the tube the counterweight could be of an advantage, which is why I queried whether this counterweight is only in the fork mounted LX OTA's or if it is in all Meade 12"/14" OTA's?

robz (Robert) · #31 28-02-2011, 05:48 PM

O.k, so what's the verdict then fellows?.
In the Meade 7 inch Mak article below, the writer states that some OTA's were made WITHOUT counterweights so we are left in the dark here a bit.

I am waiting on a 12 inch LX200 ACF OTA which is only a week or two away.
This will be one of the most recent batches to come out of the factory, so when I get it I'll know soon enough if the weight is in there.

Either way, the removal is way too risky and voids warranty. The process is madness unless you have an older tube model that cost a lot less than new

.

Andrew, it would make sense that your C11's weight is all in the back. The main mirror, holder and focussing mechanism etc. would weigh a lot more than a thin corrector plate and secondary mirror up at the front?

Merlin66 (Ken) · #32 28-02-2011, 05:54 PM

I think it's pretty definate that the 12" ( and probably the 10") do have the large cast iron interior counterweight. It makes some sense and a method of getting the OTA close to balance at the Dec axis.

GrampianStars (Rob) · #33 28-02-2011, 06:52 PM

Quote:

Originally Posted by renormalised

I think we can safely assume that all Meade SCT's have this counterweight.

Ahh! NO !
The 12" LX200 GPS doesn't. in fact is rather nose heavy.
I had to add a Peterson on axis rear cell counterweight from :- http://www.petersonengineering.com/sky/balance.htm
and even then the 2D ballance weights are at the extreme rear on the rail for correct ballance.

Shifting the OTA atachment.......... and lighten the scope.......

Merlin66 (Ken) · #34 28-02-2011, 07:03 PM

Rob,
Do you have a bare weight for the 12" GPS OTA??
How does that compare with the 17.2Kg of the 12" Lx Classic????

toc (Tim) · #35 28-02-2011, 07:03 PM

Quote:

Originally Posted by GrampianStars

Ahh! NO !
The 12" LX200 GPS doesn't. in fact is rather nose heavy.

Well the one linked to in this thread does, so I guess its a question of which ones do, and which ones do not. I certainly wont be taking mine apart (when it arrives in a few weeks time) anytime soon

renormalised (Carl) · #36 28-02-2011, 07:05 PM

It mustn't have been very well balanced to begin with....maybe they just didn't add one to your scope when they were making it. Or if that's the general condition of that size and make of Meade.

GrampianStars (Rob) · #37 28-02-2011, 07:45 PM

Quote:

Originally Posted by Merlin66

Rob,
Do you have a bare weight for the 12" GPS OTA??
How does that compare with the 17.2Kg of the 12" Lx Classic????

Aprox. 16.3Kg when last off the forks. Didn't see a weight in there, will do rebuild and add active cooling in a few months so will double check.
the link provided is a great reference for the LX-200 Classic
http://tech.groups.yahoo.com/group/s...A-disassembly/

robz (Robert) · #38 01-03-2011, 05:20 PM

Quote:

Originally Posted by Merlin66

Rob,
Do you have a bare weight for the 12" GPS OTA??
How does that compare with the 17.2Kg of the 12" Lx Classic????

Merlin, 16.4kg for the 12 inch LX200 ACF.
35 lbs from Meade Q&A on the intranet.

Merlin66 (Ken) · #39 01-03-2011, 05:38 PM

Hmmm
Only a 0.8Kg difference...doesn't sound like the weight of that lump of iron...more like the weight of my ADM guide bar...

robz (Robert) · #40 01-03-2011, 05:49 PM

Quote:

Originally Posted by Merlin66

Hmmm
Only a 0.8Kg difference...doesn't sound like the weight of that lump of iron...more like the weight of my ADM guide bar...

Copy that Merlin...............somethin' don't add up here does it?

You would think that a 12 inch SCT ''OTA only'' being marketed by a large well known company has already taken in to account that the OTA is in most cases than not, likely headed for a good quality G.E.M. and not a fork mount.........surely

.