Advice Needed Shortening jack actuator help

[Captain Jack]

Hi,

In order to progress with my Gibby project, I need to shorten the 18" jack to use it for declination control. So... I chopped it in half and am now stuck.



The inner tube (A) with the spherical joint had a threaded end (C) originally but that's now in the bin. Without the thread, I cannot get the worm drive "nut" ( inside the tube. How do I make the thread? The "nut" is made of plastic, which explains the play in it, and already has some threads stripped. Alternatively, how can I fix it inside the tube? Can I just bash it in with some epoxy and hope it's strong enough to hold it? Wouldn't mind replacing this with a metal equivalent...

Also, the plastic sleeve (D) that sits between the inner and outer tube is knackered. Can I get replacements for these anywhere?

Cheers
CJ

 

[Archived-1]

I think you should have cut the other end off from memory,

 

[Vipersan]

Not sure I'd ever trust a shortened actuator ..
Perhaps you should just splash out on a 10" Jaeger
http://www.primesat.eu/satellite_dish_actuators_motors.php

or is that still too long ?
rgds
VS

 

[Archived-1]

Take a look here CJ.

http://www.satellites.co.uk/forums/threads/adding-declination-control-fibo-90.147280/

 

[Captain Jack]

Vs, I already have a 10 inch one but I fear it might not be strong enough.

Saw that, Martin, but doesn't really help

 

[Vipersan]

Vs, I already have a 10 inch one but I fear it might not be strong enough.

Saw that, Martin, but doesn't really help

No need to brag about your 10 incher CJ ..
;)
Well fwiw I shift Christinas elevation with a 12 inch superjack with no issues so can't see why it wouldn't be strong enough..?

 

[Captain Jack]

You do? Hmm.. and is the jack pulling the dish or pushing it? IOW, is the jack at the top or bottom of the dish?

 

[Vipersan]

Well I guess my situation is different to yours ..
Being a PF the bulk of the weight is closer to the top of the pole ..IE the pivot point ..but still Christina's is a heavy girl ..
Here is a quick pic ..so you can see how flimsy the elevation jack is ..
rgds
VS

 

[Archived-1]

Quick hi-jack sorry CJ, VS would you mind posting a few pictures at different angles of your mount please, I am starting work modding the az/el mount in the next few days and I like the look of your mount .

 

[Vipersan]

Quick hi-jack sorry CJ, VS would you mind posting a few pictures at different angles of your mount please, I am starting work modding the az/el mount in the next few days and I like the look of your mount .

No probs Martin..but will be tomorrow now as I'm just about to dunk myself in the bath I just ran ..
;)

Do keep in mind I dont change the declination ..as this would present soooo many problems..
I actually change the Elevation ..which works just as well...if not better for me.

 

[Captain Jack]

Vs, so if that bolt holding the end of the jack snaps, the dish with crash pivoting down?

 

[Vipersan]

Vs, so if that bolt holding the end of the jack snaps, the dish with crash pivoting down?

Indeed it would CJ ..but in 20 plus years this has never happened ....

 

[Archived-1]

You could adapt some sort of a safety strap to it just in case, to stop any damage if the worst did happen .

 

[RimaNTSS]

Sorry, but I do not understand idea of shortening of actuator To get maximum precision and strength is needed to use actuator as long as possible. I would say, option A is much better than options B and C.
Safety strap, made for example of INOX chain is good idea. Anyway you need it not only for safety but also to be able to remove and change actuator.

 

[Captain Jack]

Rimant, I agreed with you but there's very little room for the actuator. Thinking about it now, I might change the design a bit.... Shame the 18" jack is ruined now

 

[Clabs]

CJ - if you don't mind - how did you get that plastic nut (part b) out? Does it just unscrew and is it LH or RH thread? I ask because I have been v e r y slowly refurbing a CM 1.2 and 18" actuator and I wanted to get that nut out to push some lithium grease in there. Mine seems locked solid so I have left it be for now.

Sorry for the hijack.

Cheers, Mark

 

[Captain Jack]

Mark, it unscrews anticlockwise, just like a normal nut. It's in quite tight... I think it was size 23 spanner.

 

[Archived-1]

CJ I did come across a 6.5: jack with a 600lb pay load on a US site last night, I can get you a link if it is any use to you ?.

 

[Vipersan]

More Hijack ..appologies..
For Martin ..
Any other angles needed blease specify.
rgds
VS

 

[Archived-1]

Thank you VS, very much appreciated . I will start a new thread when I get all the materials.