Petterson Dec Clutch upgrade

[beren]

Had the opportunity tonite to install the Petterson clutch kit on the LX200 . This mod improves the holding ability of the standard declination lock , its a major weak point in the design of the scope which i first found out when i used it for the first time . In full lock you can still move the tube in standard mode and just doesnt feel secure unless you have counter weights which i did get to improve the situation .

The Petterson kit comes with complete instuctions , a cork gasket , a little bag of lithium grease and a allen key to take off the fork arm cover. The basic procedure after taking the cover is removing 2 gears and cleaning the factory grease and cleaning grease off the worm and worm gear . Had a little trouble removing the gear plus theres a fair amount of grease that makes things messy . After cleaning all that up the grease that comes with the kit needs to be applied then the cork gasket is inserted in between the reinstalled gears . After all that and the cover put back on the operation is finished .

Ok so does it work ? Sure does , even with all the counterweights down the back the tube hardly moves with the lock not engaged , moving it by hand nearly equals the same tension the original set up had . Engage the lock slightly and the tube is totally immovable well as much as i dared to push. One thing im worried about does this mean having counterweights become unneccessary or you still need them to ease pressure on the drives . If so its hard to judge the balance because the tube doesnt move practically out all with what i tested it with .

Well it looks like i will have peace of mind at last , should have done it earlier .

[Dave47tuc (David)]

Aragorn,
Now you have the clutch kit in, yeh and it does work very well.
I still suggest you and everyone who has a LX200 keep it balanced as best you can.

I have a heavy Astrozap dew sheild, but this is offset with the 2 inch diagonal and the big eyepieces. I still have a small counter weight on the back just to keep things balanced.

My wrorry is the plastic gears i don't wont to strain them unesessarly.

Another suggestion is your upper slew rate is set at 4 or 5. My scope does not slew at maximum, I'm not in that much of a hurry.

Best.

[beren]

Thanks for the reminder Dave , ive been meaning to adjust the max slew rate , ive followed threads over at the cloudy nights forums and the yahoo group about this issue and opinins are divided but its best to be cautious.
I noticed the dew sheild on your scope , im ordering the flexi type that are on special at astro-optical but the one youve got looks great.
checking the dec lock this morning i must say the tube is very stiff to move when unlocked but once locked everything seems to be A-ok . Dave do you have the focuser mod is that worth it and is it easier and harder to install.
Cheers

[Dave47tuc (David)]

Aragorn,
The Dec will now always feel a bit stiff, i suggest not to over tighten it.

I have the focuser kit installed. It helped with backlash but it does not fix any mirror shift. Some have the idea it does.
Not to hard to install, but i did have trouble. If you have no backlash problems leave it. It does work well.
It is a bit more fiddly than the clutch kit, but not much.

I also have the mounting plate, a great help, also the eyeopener. You need this with the big eyepieces.

My astrozap sheild works really well, its felt lined but heavy. It cost nearly $300 shipped to my door from the US.
It would be cheaper now the dollar is a bit higher.

Best.

[rumples riot]

Hi guys, great to have you guys here, especially for LX200 info and discussion. Where can I get these kits, as I would like to get bobs knobs and a few of the other mods. I think Bintel has this gear, but the store here in Adelaide is so Meade protective, they threatened to waiver my warrantee if I installed the mods. So I will do the mods myself but need some tips on where to get the gear.

Paul

[Dave47tuc (David)]

Hi Paul,
You will void any warranties if you change the scope in anyway.
I did it anyway, but thats me.

I got the clutch kit from Bintel, but the rest i got from Pete.

I also have Bobs knobs. I hardly ever change the collimation, but they work well. No more allen key.

If you have any problems or need advice I'm sure we will be glad to help.

Best.