Advice Needed Backlash in Super Jack Actuator

jenseneverest

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Hi all, bit of advise required please

I have an 18 month old Super Jack Actuator on a polar mount 1.2 CM dish. I have noticed some backlash in the ram itself. It is about 2 - 3 mm
BUT by the time that free play is transferred to the dish face i am able to move the dish east / west quite a few degrees....
As an example if i move from 28.2e to 7e i will have perfect signal, but if i then go to 22w and return to 7e i will have to peak the signal again.
Is there any adjustment on the Actuator itself to take up this backlash ?
I have a plan in my head to try overcome the issue using some stainless steel springs.....Obviously this is not an ideal solution !!
TIA
 

ozumo

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I have a similar issue. Approaching a satellite from one side seems to work - I used to always move to an east sat from the west, and vice versa. So moving from 28.2E to 7E I'd go to 5E first and then back to 7E. You'd most likely have to re-store all the positions in this manner. Now though I just peak the dish manually with the V-Box.
 

jenseneverest

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Thanks, it would appear to be a common problem from what i can find googling. I guess there is no adjustment and the wear i am seeing is within the actual gearing. I have also found that the ram has a nominal load rating of 400 pounds (to a max of 1200). The plan will now be to add some springs to take up this backlash. I have exactly the issue you describe above, adjusting the V-box has become tiresome, and my V-box is hidden away in a cupboard (normally) as they are ugly beasts lol.
Will add some pics if i have any success with this spring idea
 

ozumo

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Gas struts similar to those on on car boots may also work.
 

Channel Hopper

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From memory the play in the actuator normally starts when a bearing in the back near the gearbox starts to corrode away. It can be replaced, but you would need to find the same sized item and get the old one out beforehand, not easy after a few years of sitting in water.
 

Captain Jack

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Mostly jacks will have some sort of play in it, which unfortunately translates to a bigger effect at the dish end. Especially when fully extended...

It's much easier to throw it out than fix, given then they start rusting through at around the same time. (I am usually anti-throwaway but you can't polish this particular turd)
 
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