Paint Stripper to Clean truss

[johnnypalmer]

Hi Guys,

 

I have already done and search and people dont seem to think cleaning truss is possible - but I have heard that paint stripper can work.

 

Any idea which one works? How do you go about cleaning it?

 

We just bought about 60metres, which for us is a lot of kit and obviously want it looking really good.

 

thanks in advance

[zonino]

depends what your trying to clean off it!

[mac.calder]

If you are hoping to get back that nice shiny look ... not going to happen. Aluminium oxidises rapidly - the dull grey being Aluminium Oxide - so the only way you could get it shiny would be to remove the outer layer of oxident, and coat in a lacker of some sort in seconds, although I think you would be better off leaving the truss the dull grey as it acts as a form of protection.

 

If you are just trying to get off sticky stuff, then shellite (NFI what it is called over in the UK) and elbow grease. Paint, use your stripper.

 

See if you can get an intern... that is the sort of tedious job that you unload onto them. Damn tedious work and bad on the back. Think about living with it if it is not too bad... or cover it with another permanant stain... ie stage black matt paint.

[Andrew C]

Someone with a better memory of their chemistry might want to confirm that is is not a good idea to use caustic soda, or other alkaline solutions on ali.

[Simon Lewis]

Someone with a better memory of their chemistry might want to confirm that is is not a good idea to use caustic soda, or other alkaline solutions on ali.

<{POST_SNAPBACK}>

 

Pure aluminium will dissolve in sodium hydroxide:

 

2Al(s) + 2NaOH(aq) + 6H2O = 2Na+(aq) + 2[Al(OH)4]- + 3H2(g)

 

however, the aluminium oxide layer found on truss can also be dissolved by sodium hydroxide:

 

Al2O3 + 2 NaOH + 3 H2O = 2 Na+ + 2 [Al(OH)4]-

 

(sorry I can't do super/subscript).

 

 

Many paint strippers used to have a methylene chloride component. However, this is potentially carcinogenic, poisonous and narcotic.

 

Neither the solvent or alkali based product is pleasant to use indoors on large surfaces, and both would require a COSHH assesment, PPE etc., etc.

 

I suspect you need to either get used to the present finish, or buy truss with a chrome type finish....

[Jivemaster]

Truss can be painted to conceal blemishes as the polished/brushed finish is wonderful while perfect, but.........

 

Is the truss of UK manufacture, if so sending it back to the manufacturers for cleaning and INSPECTION is an option. You of course have bought the responsibility for the inspection regime along with the truss. There must be a good way of stripping the paint as the welds all have to be inspected and can't be inspected through the paint.

[jagardner1984]

Could you (preparing to have head bitten off) use a wire brush?

 

Unless you know exactly what you are doing, do you want to be applying very strong chemicals to rated equipment ???

[timmath]

If it has been painted with emulsion paint, try pressure washing it.

 

Tim

[Chris Higgs]

Painting trusses is a problem. The Standards are to be reviewed to reflect this.

As has been stated, paint covers defects, and mechanical or chemical cleaning is not recommended unless you have selected the paint with a view to cleaning it off to start with.

Pressure washing may work if the paint is water soluble.

Do not bead or sand blast it or use any powered tools without the OK from the manufacturer.

Many of the manufacturers will tell you not to paint trusses.

HTH

(By the way, being picky; was this truss bought second hand, painted? If so, were you able to inspect it carefully before parting with the dosh? Also in order to discharge your duties as an employer/self employed person, to inspect it and make a report of inspection before putting it to first use....)

[Jivemaster]

You really do need to talk to the manufacturers, assuming you can find them! Organic paint strippers are all noxious chemicals from a breathing viewpoint, inorganoc strippers may well start to corrode the tube faster than you think.

 

The truss when new will most likely be chemically cleaned of all the weld flux and splatter, and perhaps electro-polished, Then it should have been inspected, and certified OK. Really this is where you should be looking. Paint is used to cover blemishes in apearance and may cover weld and tube damage too.

 

Try the manufacturers for a brush on, spray off stripper that you can use in a reasonable COSHH regime, and dispose down the drain.

[Nick Evans]

When all else fails, the aviation industry has been stripping paint from aluminium structures for many many years. You may find a small aircraft refinisher can strip your paint, but it may cost less to replace the truss.