# Forum Home Renovation Metalwork & Welding  Clean cut gal before cold gal?

## r3nov8or

I cut some new gal RHS today and would like to paint the cuts with cold gal. The steel is still greasy (probably applied for it's ocean trip from China), so what's the easiest / best way to clean the grease off before painting?

----------


## Gaza

Thinners   
Sent from my iPhone using Tapatalk

----------


## r3nov8or

> Thinners   
> Sent from my iPhone using Tapatalk

  Thanks Gaza.  
(Probably the only chemical I don't have on hand right now. Off to the green shed again  :Smilie:  )

----------


## Gaza

Actual cheaper to go to super cheap   
Sent from my iPhone using Tapatalk

----------


## r3nov8or

Ok! About 100m apart at my local

----------


## Marc

Yes, lacquer thinner is the best if you want to spray cold gal.
Before you do, make sure you dull the edges with a file.  :2thumbsup:

----------


## r3nov8or

Is there much difference between 'general purpose' and enamel type thinners and lacquer thinners? Is there one that shouldn't be used for this job?

----------


## Marc

Check the cold gal you will use, it should tell you which thinner to use. 
Since you are using it to clean the oil off the steel and not to dilute the paint, I don't think it really matters much. By the time you are painting the thinner will have evaporated. You could use soap and hot water of a pressure cleaner for argument sake ... not that I recommend you do ...  :Smilie:

----------


## r3nov8or

Thanks Marc

----------


## Random Username

The difference between all the general purpose/lacquer thinners is in the aggressiveness and flash-off time of the solvents, and you'll really only notice the difference when spraypainting with car-type paints. GP thinners are the more aggressive solvent mixes (as they have to cope with a range of binders), dropping down to your lacquer thinners and high-gloss lacquer thinners.  
The high gloss thinners are a slower evaporating mix to give the paint more time to self-level after hitting the surface... with slower meaning 'more towards the five minute end of the three-to-five minute flash off time'. 
Wax and grease remover/prepsol is a handier option as its not quite as stinky and a little less likely to ruin plastic based surfaces (like, y'know, if you just happen to have a galvanised plastic pipe or somthin'...)

----------


## phild01

> The high gloss thinners are a slower evaporating mix to give the paint more time to self-level after hitting the surface... with slower meaning 'more towards the five minute end of the three-to-five minute flash off time'.

  Wish I had known that long ago with my car painting projects.

----------


## r3nov8or

I found various options in Diggers range (went to Bunnings after all), with varying amounts of Hydrocarbon Liquid, 65% - 100%. As my need was specially for cleaning, I went with the 100% which is branded Enamel Thinner and states in uses "Removing wax and *grease* prior to spraying". It was also the cheapest. Judging by a very dirty rag after cleaning it did a great job and was dry in 'seconds'. 
The ~35% of contents of the others looks like it is varying amounts of Acetone and Ethanol.

----------


## Marc

Remember to file the sharp edges down before you paint.

----------


## r3nov8or

> Remember to file the sharp edges down before you paint.

  Thanks Marc, yes, used a flap disc for most of it, filed hard to reach places.  
I find it's always best to use electricity whenever possible  :Smilie:

----------

