How to beat rust?

[thecaretaker]

I live near the sea and after a blustery winter, the nuts and bolts of my satellite dish have become very corroded. So, with the warmer weather coming (I hope) I think it is time to re-new my set-up.

The dish, a Aluminium Fraccaro is fine, so is the bracket which is still like new. I've been very please with the dish and it should last me years.

I know my TK brackets need replacing but I know where to buy a really solidly built galvanised set of those.

The main rust is on the motor bracket to the mast (threads and nuts rusted also more seriously the zig-zaggy bracket thing that squeezes the aluminium mast) and on the adjuster nuts on the side of the motor casing.

This is the second motor in almost as many years. Its a dark superior motor. The previous dark motor seized up with corrosion)

So, I'm looking for a new motor that comes with really good quality galvanised nuts, bolts and bracket.

Any suggestions?

Or can I source some good quality galvanised replacements? If so, from where?

I can't be the only person with this problem can I?

 

[Lazarus]

Prevention is another strategy - I treat all my fasteners with Kurust each year and when it's dried apply a thin coat of grease. Kurust also applied to motor bracketry.

Any that appear excessively corroded are loosened and re-tightened to keep the threads operable.

Takes only a few minutes.

Not sure how your previous motor seized up with corrosion ............... the internals are pretty well protected and there isn't a lot that can go wrong with the stub. Also,the very nature of the beast is that is it exercised frequently, so I'm not too clear what the root of your problem is, despite the inclement conditions.

 

[thecaretaker]

Hi Tivu

It was the black lash adjuster. When I replaced it, I opened it up and posted the pictures on here. It was basically a little allen key screw that wedged a block of metal against the side of the motor. The thread completely rusted and when I tried to turn it, it snapped off inside. There was so much play that I had to buy another.
Found it: _http://www.satellites.co.uk/forums/dish-setup-single-sat-multi-sat-motorised-systems/155557-super-dark-motor-method-backlash-adjustment.html

I'll take your advice about the Kurust. Seems a wise thing to do.

I'm thinking of replacing the aluminium mast too. Although it is a thick good quality aluminnum mast, it still deforms a bit when trying to tighten up the motor bracket. I find it a game getting it tight enough to stop any movement on it but not deforming it and putting the dish out of alighnment. I'm sure a good solid bit of scaffold tube would be more sturdy. My problem maybe I'm too much of a perfectionist.

 

[Lazarus]

Ah, I understand now: Sadly I didn't recall that other Thread, so thanks for the link.

And yes, ditch the aluminium mast. Far too light duty for motorised satellite use, even with T&Ks.

The clamps don't bind properly and leave gouge marks which will only get worse when you have wind loading stressing the system.

 

[sonnetpete]

You might want to consider a Clarke Tech HH390 diseq motor, which I upgraded to when I changed my dish last year. I'm impressed by the quality of it's clamps, brackets and motor body. Agree with Tivù though, a preventative rustproof treatment would be beneficial considering your location.

 

[smiffie]

Recently I refurbished a H to H motor which had been up for about 15 years, all the die cast components were fine, but all the bolts were rusted badly. I replaced all the nuts and bolts with stainless steel replacements and the V-bolts with stainless steel screwed rod formed into Vs. Not a cheap option, but it reduces the long term maintentance costs. There was not a problem with the pole as it is a 50mm diamater, thick wall galvanised steel scaffold pole - I don't use anything else nowadays. The 2" V-bolts gripping the pole were that rusty they had to be sawn off, these only seem be available as zinc plated so I covered the nuts with self-amalgamating tape. I've also done the same with any other steel components I suspect will corrode in the future, you see a similar approach when they cover exposed bolts on things like bridges and lamp posts where they use a type of tar soaked tape.

The last few Technomate Diseqc mounts I've fitted seem to already have stainless steel U-bolts/nuts, but they are let down by the painted mild steel pole mount.

 

[Vipersan]

I agree with Smiffie on this one ..
on my recent big dish refurb I replaced (where possible) all small nuts bolts and washers with marine grade stainless steel ..
The big nuts and bolts (Imperial threads) where treated to a good wire brushing ...a galvanised paint spray ...and finally a generous helping of copper grease..
prevention is better than cure I think.
rgds
VS

 

[smiffie]

a galvanised paint spray ...and finally a generous helping of copper grease..
prevention is better than cure I think.
rgds
VS

Does that paint work? The bloke in the local engineering suppliers showed it to me, he said they sell it to people who fit steel gates. They use it on site when they've had to make a cut in order to "encourage" a gate to fit, which would obviously expose the steel where the cut was made. Also does the copper grease wash off after a while, pretty sure I've tried that approach and reverted to self amalgamating tape.

As an aside, these gate manuafacturers' can sometimes be a good place to buy replacement "eye" bolts used to set the elevation on H to H and polar mounts. I actually had a friend fabricate a replacement for the one in the picture (Exhibit A). The stainless steel screwed rod was heated up and formed into a "V" in a vice, using the old bolt as a pattern (Exhibit :-

 

[Vipersan]

Hi Smiffie ..
The paint sorta works ..
Half the battle is using a good quality metal primer..
Its a poor mans version of galvanization ..and doesn't protect forever..
It does scratch ..and it does wear ..
Not a real substitute for proper galvanized plating..
The Copper grease is good and lasts a good while ...but reapplication is needed every few months to stay one step ahead of the weather..
In short ..non of these measures is as good as replacing exposed metal threads with stainless steel where possible...
rgds
VS

 

[thecaretaker]

Well, I've replaced my bits. The T&K brackets are proper hot dipped galvanised and with a life expectancy of 20 years+ (according to the site I bought them from) and came with 'v' bolts for the mast.

A mate at work found a nice 2ft scaffold pole. It is clean (after I got the lumps of pug off it) and I've got a really solid grip which doesn't deform as I tighten the nuts.

As you see, the original threads and bolts from the Fraccaro are still as good as new.

The new dark motor's bolts is a worry. I will get some heavy duty grease and see if coating it with that will help. Failing that, I shall take your advice and see if I can get stainless steel replacements.

But, it's up for now and the family can watch the telly again. Hopefully, only the motor threads and bolts to worry about.

Oh, the cap on the top is from my shaving cream spray can. It is to stop rain from pouring down the top of the scaffold pole. 'don't laugh'

 

[Lazarus]

That, Sir, is what we call a "proper job"!

 

[smiffie]

Well, I've replaced my bits. The T&K brackets are proper hot dipped galvanised and with a life expectancy of 20 years+ (according to the site I bought them from) and came with 'v' bolts for the mast.

A mate at work found a nice 2ft scaffold pole. It is clean (after I got the lumps of pug off it) and I've got a really solid grip which doesn't deform as I tighten the nuts.

As you see, the original threads and bolts from the Fraccaro are still as good as new.

The new dark motor's bolts is a worry. I will get some heavy duty grease and see if coating it with that will help. Failing that, I shall take your advice and see if I can get stainless steel replacements.

But, it's up for now and the family can watch the telly again. Hopefully, only the motor threads and bolts to worry about.

Oh, the cap on the top is from my shaving cream spray can. It is to stop rain from pouring down the top of the scaffold pole. 'don't laugh'

Yes, that's the right T&K to buy in my opinion, the 'V' bolts will almost certainly be zinc plated unfortunately. Now that you have the scaffold pole, it would be the T&K that will crush/distort if you overtighten. I'd be surprised if the "U" bolts on the Darkmotor are not Stainless steel, simple to check, see if a magnet sticks to them. Stainless steel nuts and bolts are usually stamped up with A2 or A3, I think A2 is the better quality. But then again, perhaps you are fed up with looking at it and probably just want to watch telly!

On a more serious note, how are you now going to control any rogue shaving foam?

 

[mouse3]

Use plastified paint,it s UV resistent ant last longer.Five years no problem.