![7550pic[1].jpg](https://i.imgur.com/XEkhaet.jpg "7550pic[1].jpg")
So I've got a powerhead motor that sits right next to a giant vat of saltwater for its life, and the housing isn't sealed against moisture. So inevitably salt and water are going to get in. What is the best anti seize/galling compound for screws facing salt and high humidity? I've heard good things about ptfe greases and moly disulfide, though the moly seems very overkill for this low temperature application.
tl;dr: best anti-seize compound for small screws?
On a related note, how can I extract a seized and slightly stripped 3mm screw?
I'm looking at the #1 grabit which says it works on screws down to 3mm. Will it be able to get out a seized screw? I can't take a torch to it as it would demagnetize the magnet the screw is holding on and quite possibly damage the motor directly beneath.
marine non-metallic is the stuff, it's not the best anti-seize or anti-galling compound but it's the most resistant to warm salty water.
ez-outs are for times when the head is reamed out but the thread is free to turn, if you could only reach down in there and grab it. using one on a seized screw will snap the ez-out off in the hole and then you're ker-fucked. a left hand drill is what you want.
>>913477
Well fuck. Drilling it out would damage the mating threads, right? Because this is in the motor shaft, and I doubt I could rethread it.
>>913517
Also on that note, where the hell in the states am I going to find a 1-2mm left hand drill bit locally? God this is such a shit situation.
>I've heard good things about ptfe greases and moly disulfide
Yeah, they are great to reduce friction, but that's not what you want.
What you want is 90% technical vaseline heated and mixed with 10% bee wax. This stuff is a legend in Germany and used by the military for a century or so. We may have had 99 problems in our wars, but corrosion ain't one of them. Nowadays, it is very popular amongst offroad and classic car enthusiasts. Google "Mike Sanders", that's the same stuff.
Bump on the screw extraction via drilling.
Will I damage the mating threads?
>>914285
Start with small diameters and then open up to 2.5mm for an M3 thread. Then use a thread-cutting tap to finish your work.
If you really care about preventing corrosion in such an environment then your best bet is to get marine grade stainless screws of the same size and thread pitch.
Anything else you do will only be a short term measure and will need some sort of maintenance plan. Although marine grade stainless does still corrode it fairs far better than galvanized steel with a coating of most things.
>>913441
Nowadays I use dielectric grease for this, even though it's made for ensuring a proper seal in my RF connectors. This dielectric grease comes with many names, as I've used quite a few of them, so these may or may not be brand names:
111 Grease
Molykote
But what we used offshore (as in, on a ship) for true industrial strength antiseize is copper paste: Spritz some onto the bolts/nuts/screws, and you have something that handles sea water spray (and even wash) pretty well. The water temperatures was all the way from below 0C to ~25C
>>915023
Is it really necessary to walk through smaller diameters? 2.5mm is already pretty small.
