Lubricating aluminium-on-aluminium bearing surfaces?

[Eric The Viking]

I've got a tower scaffold up at the moment, for painting. It's being moved a lot as you might expect, requiring a lot of levelling. There are huge castors, and levelling screws in the bottoms of the columns, with acme-type square threads and three-pronged levelling washers.

I did try lubricating them before I started, cleaning with WD40 and then using a bit of engine oil, but it's next-to useless. The fullly-erected tower is pretty heavy, and they're still jamming up, beyond my ability to twist them and lift and grab the bottom (to stop that rotating), all at the same time.

Any recommendations as to a good practical lubricant for the job?

I've got lithium grease, copper grease, vaseline, Liberon machine wax, engine oil, hypoid gear oil, 3-in-one, "teflon" bike chain spray, and even the dreaded WD40. I can get something else if necessary. I don't care if they're too slippery (can easily jam them), but right now they're almost immovable under load.

Help very much appreciated on this, before I pull a muscle!

Cheers,

E.

 

[MusicMan]

Aluminium on itself will always bind. Conventional oils and greases won't help a lot. It needs a solid barrier lubricant. So try the Teflon sprays. I'd even try powdered Teflon or nylon. Tricky.

Keith

 

[adidat]

I havole found the perfect producr for levelling scaff towers, framing hammer!

Adidat

 

[Eric The Viking]

Thanks chaps - pretty much what I thought.

This morning, I've actually been lifting one corner at a time with a trolley jack (thankfully it's on concrete presently, although that's far from level nor flat). That gives me enough slack to tweak it and then drop it down again to see if it worked.

I wrote "washers" earlier, but they're actually giant-sized wingnuts (with three prongs). The tower proper sits in a cup on the upper side. I'll see if I can contrive some sort of slippery washer (pair thereof) to go in the cup and maybe try copper grease on the actual threads - I appreciate it won't be very good, but I've probably nothing to lose.

 

[Rorschach]

A thrust bearing on each screw would probably work great if you could get them in a suitable size.

 

[Eric The Viking]

Quite agree. The internal diameter is about 2" so probably out of my league somewhat.

I have to dismantle the thing to do the next part of the house in a day or two. So I'll clean the threads thoroughly and have another look at what might be made more slippery -- safely!

 

[mbartlett99]

Ally is crap a this sort of thing as you've discovered. Firstly don't use any metal based lubes - especially copper, can get a nice little galvanic cell going. PTFE based lubes such as tefgel and loctite do one are a good bet - very sticky but clean off with acetone. Oils etc won't last long and WD40 isn't a lube in any case.

 

[AES]

Blimey EtV, you do come up with some problems sometimes!

Agree with everything said above, especially use of stuff with any other metallic compound in it, like copper grease.

IF you can get it, I'd suggest colloidal graphite - it's a sort of non-metallic "paste", the only use for which I know is for lubricating critical aero engine parts which aren't hot - e.g. the "fir tree roots" where fan blades slot into the fan hub. But I've no idea where you'd get any (and I have no contacts for such stuff now I'm retired) and even if you could get it I've no idea what name to ask for! And I bet it costs an absolute fortune too!

The nearest "domestic" thing to the above that I can think of that MAY work is that slightly sticky powdered graphite that comes in small plastic "puff" bottles, used for lubricating door locks, hinges, etc, especially for cars n vans. It should do the job for a while but I've no idea how long it will last. It's also VERY mucky if you get it on your hands, so it needs to be kept to the threaded areas as much as you possibly can, applying to one area with a gentle puff from the bottle and then spreading it around with a small soft paint brush (child's water colour set type).

At least it's pretty cheap stuff though, and it goes quite a long way - I don't know but I'd guess you'd find it in Halfords in UK (we don't have Halfords here but a more-or-less equivalent does have it here).

No guarantees, sorry, but it may be worth a try.

HTH

AES

 

[Eric The Viking]

Thanks - you guys are brilliant.

Snow notwithstanding, I need to break the scaffold down tomorrow probably (or Sunday, as the next section has quite different heights for the four legs.

I'll have a look at the threads when I do that, starting off with some careful cleaning. What do you think about something like talc or powdered chalk? I only ask because I have some. I've a funny feeling though, that either might actually make matters worse (these things also get wet when it rains as the design traps water running down the framework).

 

[AES]

Nothing wrong with using WD40 and a wire brush to clean the threads when stripping the tower down Eric. WD40 does disperse moisture.

But now I hear that it's likely to get wet with rainwater running down the poles (I've never looked at one of thos things closely) then I THINK I'd steer clear of any dry powder, chalk, or my suggested graphite stuff.

Any chance of rigging up some thick rubber bands - or those thick rubber seals from plastic rainwater goods - or even several layers of masking tape - to deflect as much rain water as possible off the threads? A bit like the cotton things the Victorians used around their piano legs to stop giving the ladies racy ideas!

AES

 

[Eric The Viking]

If you think I'm taking a piano up that thing...

But yes, that's a good idea, I think. I also need to block the tube at the top.

The threatened deluge this evening hasn't yet happened so I may get more done tomorrow - got a few hours work yet before I must move it.

Thanks.

E.

 

[AES]

Eric wrote: If you think I'm taking a piano up that thing...


Pure idleness

AES

 

[TFrench]

We only ever use a splash of WD on ours at work if its really stiff. Most stuff just attracts grit and makes things worse after it being knocked down and chucked around a van a few times. If you've got an assistant the easiest way to adjust it is for one to lift one end to take the pressure off and the other to work the screw. If the thread is a bit sticky a bit of persuasion with a steel toe cap normally does the trick.

 

[Phil Pascoe]

I havole found the perfect producr for levelling scaff towers, framing hammer!

Adidat

Didn't you mean to say "someone else's scaff towers"?