Degreasing Bare Wood

[Achilles]

I'm varnishing part of the saloon, have sanded back to bare wood and intend to use Epifanes Rapidclear because it doesn't require sanding between coats. Epifanes recommend the bare wood is degreased before varnishing and sell proprietary degreasers, but do I need this, can't I just use something like meths or white spirit?

Thanks

 

[ccscott49]

Meths would be better as it dissolves grease, acetone would do also, but a word of warning, watch the fumes from both, inflamable and toxic.

 

[Chrusty1]

Not always, meths is missible in water, so doesn't always do a good job of cutting grease, Acetone or cellulose cleaning thinners will do a better job, but if using a lot best get a bio mask if working inside.

 

[misty56]

Depends on the amount of grease we're talking about. White spirit will help get rid of heavy deposits but it will leave a light oily film which has to be got rid of with a more volatile solvent.

Nitro-cellulose (celly) thinners or acetone is what I'd use. (Celly thinners is basically just acetone and toluene.)

I use cellulose thinners, usually, 'cos it's cheap and easy to get, though it depends what's in the shed.

Please read the MSDS-- these are aggressive, highly flammable solvents. (Read that last bit again.) If you have any history of asthma, intolerance of solvent vapour or exzema DO NOT USE THEM.

You need to wet the surface and soak it back up before it dries, otherwise nothing has been achieved. Do a small area at a time and ensure plenty of ventilation. Use cotton rag that does not fluff and turn it frequently. DO NOT EVER throw the used rags into a bin or pile-- this stuff can spontaneously combust.

You want to make sure absolutely every trace has evaporated before applying paint

As well as being a great degreaser, celly thinners is great paint stripper, will melt thermoplastics and damage gelcoat. Use with great care.

NB-- celly thinners comes in two grades-- you don't need the topcoat type for this (It just has less water in and costs twice as much.). Celly thinners is very hydrophilic so keep the can well stoppered, or it will eventually rust through the bottom.

 

[Grajan]

using alternative Solvents to degrease can cause more problems than you would imagine due to them lifting and then respreading contaminates
the manufacturers product will chemically breakdown any contamination allowing it to be wiped off and transferred to the cloth with any degreasant residue that has been absorbed into the timber being compatable with the initial coats of varnish / paint
very often the problems dont arise until after all the coatings have been applied and a restrip is the only way to resolve the problem!

 

[Achilles]

Thanks everyone for your excellent advice.