Gun wash cheap solutions?

[brightspark]

i had half a gallon of of industrial paint stripper in a metal can . went to get it and the bottom was rusty and starting to leak caught it just in time as it was up on the shelf . that would be bonny going all over the place

 

[Jelly_Sheffield]

I use it just to get the large amount of paint out of the gun & cup, and follow
with carb cleaner immediately, long before any paint has cured/kicked/cross linked/poloramized.

Fair, and if you have a process that works for you that's great.

As far as "exhibits a higher flammability risk" We are dealing with paints with strong solvents in them along with all the cleaning chemicals to begin with, precautions
are the rule here anyways. I don't see gun wash & paint thinners being any less
flammable than petrol/gasoline.

The flashpoint of E10 Petrol is -47°C, the vapour pressure at room temperature is considerable*, and the vapours are heavier than air.

*Edit: There's a potentially important transatlantic difference here, the maximum Reid Vapour Pressure for petrol sold in the UK (100kPa, 14.5psig) is almost double what's allowable under EPA regulations in the US (7.8psig)... So our petrol gives off vapours much more readily than your gasoline does.

The flashpoints of common gunwash products are generally in the -20°C to 7°C region, the vapour pressure is generally (IME) lower (although difficult to quantify as it will vary from batch to batch), and most (but not all) of the common solvents involved have densities lighter than air when in vapour form.

You're absolutely right that taking sensible precautions is crucial either way, and they are both potentially dangerous if you don't take good care, but between the two, petrol does have higher risk factors.

 

[Jelly_Sheffield]

same here . i lost a gallon and didnt even smell it in garage

One of the companies a previous employer of mine supplied solvents to lost ten 40ft shipping containers worth of gunwash after the cans rusted through whilst held up in customs at a port in Africa.

Luckily for us someone in technical sales had explicitly warned them not to package the grade they purchased (which could have substantial water content because it was cheap as chips) in the disposable tinplate (3A1 type) jerrycans for export or long term storage... Internally lacquered drums or plastic containers only, but you can't tell some people.

 

[Johnnybravo]

One of the companies a previous employer of mine supplied solvents to lost ten 40ft shipping containers worth of gunwash after the cans rusted through whilst held up in customs at a port in Africa.

Luckily for us someone in technical sales had explicitly warned them not to package the grade they purchased (which could have substantial water content because it was cheap as chips) in the disposable tinplate (3A1 type) jerrycans for export or long term storage... Internally lacquered drums or plastic containers only, but you can't tell some people.

That’s a bit of a cache 22 situation… don’t know who is more deserving of the Darwin Award, the customer for wanting it delivered like that or the company for being stupid enough to agree having told the customer of the potential issue before hand

 

[GRW]

For cleaning stuff (& I know nothing much about paint either) - can someone enlighten an Ignoramus of the difference and applications for
White Spirit v Cellulose Thinners v Gunwash v Brake & Clutch Cleaner?

(Like many I’ll use Brake Cleaner to degrease & cleaning engine parts & associated stuff, & I think you can use White Spirit & Thinners for (Surprise!) Thinning paints (presumably thinnerd just for cellulose-based paints & white spirit for paint?).

I'm thinking one of these days - it's going to be handy to know!

 

[Jelly_Sheffield]

That’s a bit of a cache 22 situation… don’t know who is more deserving of the Darwin Award, the customer for wanting it delivered like that or the company for being stupid enough to agree having told the customer of the potential issue before hand

We supplied our customer with various materials in 27,000L ISO-Tanks, for them to process in their blending and filling plant.

When they said they wanted the cheapest possible gunwash to go straight to their fill plant for an export contract, our tech sales lady saw the issue coming mile off and explicitly warned them not to fill it into thin steel containers, or to buy a higher grade of material with a guaranteed lower water content.

They did neither of those things, rolled the dice on it surviving transit, lost it all in transit, and lost a **** tonne of additional money refunding the customer, and paying cleanup costs to the port, all of which they threatened to sue us for...

Until we pointed out that they literally did the one thing they were warned not to, and it went wrong exactly as they were fore-warned.

A few months later the directors [of our foolhardy customer] sold the business to one of our competitors for peanuts, to avoid going into liquidation.

Despite not being on the bonus scheme, the tech sales lady got a hefty bonus the following April "for her excellent judgement in anticipating client needs".

 

[Jelly_Sheffield]

For cleaning stuff (& I know nothing much about paint either) - can someone enlighten an Ignoramus of the difference and applications for
White Spirit v Cellulose Thinners v Gunwash v Brake & Clutch Cleaner?

(Like many I’ll use Brake Cleaner to degrease & cleaning engine parts & associated stuff, & I think you can use White Spirit & Thinners for (Surprise!) Thinning paints (presumably thinnerd just for cellulose-based paints & white spirit for paint?).

I'm thinking one of these days - it's going to be handy to know!

In broad brush strokes:

White Spirit is typically Hydrotreated Naphtha.

Effectively a very clean version of the same distillation fraction as diesel and Jet A1, it's a good degreaser for initial cleaning (but can still leave some residue), and can clean solvent based paints when they're still fully wet, but like petrol, won't necessarily be able to clean paints that are beginning to cure.

It's generally not suited to use as a thinner due to slow evaporation times, specialised higher grades are available for thinning oil based paints, but that's not the stuff you'd buy off the shelf.



Cellulose Thinners is typically a mixture of non-polar aromatic solvents like xylenes, and polar solvents like Acetone, Ethanol, and various esters and ketones.

It's generally formulated to match the solvent used in a particular brand or grade of 1K paint, and is made by blending technical grade solvents of reasonably high purity to ensure it's consistent in use.



Gunwash is a much looser mix of solvents that can be pretty variable, generally biased towards the non-polar ones for dissolving power.

It's only intended for cleaning, and can't be relied upon for degreasing in critical applications as it may have residual amounts of non-volatile hydrocarbons. As it often contains residual water, it's not suited for use as a thinner.



Brake and Clutch Cleaner is typically a mix of polar and non-polar solvents, mixed in proportions that will maintain a very low boiling point. Typically in the UK it will have hexane, ethyl acetate, isopropyl alcohol, and acetone. Older formulations used chlorinated solvents, but those are long gone now.

It has excellent cleaning and degreasing power, but is designed to evaporate very quickly leaving no residue, making it better suited to cleaning surfaces than flushing equipment.

Totally unsuitable as a thinner because it's explicitly intended to flash off as quickly as possible.

 

[nickk]

Interesting thread,my current 25L standard thinner is a year old,it’s not the same product as the previous bought in 2023,just won’t clean brushes as thoroughly,I always buy from Elmbridge my regular paint supply company,when I complained they told me I’d had to have done that within 6 months.

 

[GRW]

In broad brush strokes:

White Spirit is typically Hydrotreated Naphtha.

Effectively a very clean version of the same distillation fraction as diesel and Jet A1, it's a good degreaser for initial cleaning (but can still leave some residue), and can clean solvent based paints when they're still fully wet, but like petrol, won't necessarily be able to clean paints that are beginning to cure.

It's generally not suited to use as a thinner due to slow evaporation times, specialised higher grades are available for thinning oil based paints, but that's not the stuff you'd buy off the shelf.



Cellulose Thinners is typically a mixture of non-polar aromatic solvents like xylenes, and polar solvents like Acetone, Ethanol, and various esters and ketones.

It's generally formulated to match the solvent used in a particular brand or grade of 1K paint, and is made by blending technical grade solvents of reasonably high purity to ensure it's consistent in use.



Gunwash is a much looser mix of solvents that can be pretty variable, generally biased towards the non-polar ones for dissolving power.

It's only intended for cleaning, and can't be relied upon for degreasing in critical applications as it may have residual amounts of non-volatile hydrocarbons. As it often contains residual water, it's not suited for use as a thinner.



Brake and Clutch Cleaner is typically a mix of polar and non-polar solvents, mixed in proportions that will maintain a very low boiling point. Typically in the UK it will have hexane, ethyl acetate, isopropyl alcohol, and acetone. Older formulations used chlorinated solvents, but those are long gone now.

It has excellent cleaning and degreasing power, but is designed to evaporate very quickly leaving no residue, making it better suited to cleaning surfaces than flushing equipment.

Totally unsuitable as a thinner because it's explicitly intended to flash off as quickly as possible.

Thank you for the detailed explanation - much appreciated!

 

[steveo3002]

Interesting thread,my current 25L standard thinner is a year old,it’s not the same product as the previous bought in 2023,just won’t clean brushes as thoroughly,I always buy from Elmbridge my regular paint supply company,when I complained they told me I’d had to have done that within 6 months.

mine seems a weaker version of what i used to have , had a 25ltr can that decanted down into smaller ones that lasted me years , seems to evaporate fast too

guessing like anything its been cost cutting and got less good stuff now , still cleans but you can tell its worse

 

[julianf]

The stuff I buy is different every time. Same print on the tin, same supplier, variable mix inside.

I assumed it was just recovered solvent hence the variation.

I use, maybe, 10 ltrs a month, or somthing like that. Maybe 10 ltrs every couple of months?

I use it for gun wash, but also pre cleaning parts before silk screen printing / cleaning printing tools, and spraying though the mesh at the end of screen recovery to remove any residual 2k inks.