Mineral spirits Vs traditional thinner?

[NCJim]

When should I use mineral spirits over traditional thinner? I just invested is some really good brushes and was told to use ONLY mineral spirits for cleaning the brushes. Is that true?

 

[Mike Davis]

I have some $40-$60 brushes that I bought in the 70s, they are like new minus a few hairs.

i always clean them in mineral spirits (paint thinner) or turpentine then rub some clean oil into the bristles. The oil keeps any varnish you missed from hardening.

I have a different set of brushes for water based paints. Those brushes get a hot soapy wash with dish washing liquid and some of the soap gets left in the brush. When I need to use them the soap gets rinsed out and they are ready to use.

Never use the oil brushes with water and never use the water brushes with oil.

If you are using a brushing lacquer then you must clean with lacquer thinner.

I have used vinyl ink to paint with and had to use the vinyl thinner to clean that.

So, basically use the thinner that goes with the paint you are using. And anything oil or petroleum based should be followed with an oil soak to keep the bristles soft.

 

[Jeff]

When should I use mineral spirits over traditional thinner?

What's the difference in your opinion? Maybe labeled as "Paint Thinner" or a different one could be "Spirits of Turpentine".

Just curious.

 

[tarheelz]

What's the difference in your opinion? Maybe labeled as "Paint Thinner" or a different one could be "Spirits of Turpentine".

Just curious.

I have heard that the only meaningful difference between mineral spirits and paint thinner is price.

Turpentine is a different animal.

 

[ehpoole]

I have heard that the only meaningful difference between mineral spirits and paint thinner is price.

Turpentine is a different animal.

My understanding is that the difference is in the level of purification each has been through to remove undesired byproducts and volatiles.

 

[danmart77]

When should I use mineral spirits over traditional thinner? I just invested is some really good brushes and was told to use ONLY mineral spirits for cleaning the brushes. Is that true?

Jim
I use brushes for just about all of my finishing. I don't have a spray booth so the brush is the method for most of my finish work. As others have said, a cloth rag is better for some finish applications.

I think Mike Davis hit all the big points very well. I think Mike is the first person to mention finishing up the cleaning of oil based brushes with a light oil coat. To clarify a little further- After cleaning my natural bristle brush with paint thinner I dip my brush in thinned out linseed oil. I thin with turpentine and wipe it down pretty well. After a week the brush will feel a little sticky but not hard. Before use, I soak and clean in MS or turp. Ready to go again. Why the fuss? Some of these brushes are very expensive and you want to keep them in top shape.

To add one more brush to the specialty mix I would insist on a dedicated shellac brush. This brush gets a different cleaning schedule. Because shellac is "reactivated" with denatured alcohol, I don't clean is entirely. I can leave some shellac on the hairs and its OK. Before use, I soak it in DNA and shake it out. I always get DNA up to the ferrule of the brush to prevent finish build up high on the hairs. This has worked for me.

I NEVER use my varnish brush with shellac finishes. The oil on the hairs effects the flow of the shellac which is very thin.

So I have 3 brush categories: natural bristle oil, natural bristle shellac, synthetic bristles for water based paints.


Traditional thinners. I'm not sure what you are referring to with traditional thinners. To clean oil based varnishes you can use mineral spirits, turpentine, naptha as a start. I keep these around for their different dry time characteristics when thinning varnish mixes. They are also good cleaners. It seems like the MS is the cheapest so I use it most of the time. If you clean with MS and pour it in a jar the impurities will fall to the bottom of the jar. I then pour off the clear MS on top in a clean jar and reuse it over and over. The crud on the bottom can be scraped out and left to dry out on a piece of glass before disposal.

Jeff asked: MS(paint thinner) vs turpentine. Not being a chemist as I know he is, I'll touch on the empirical differences while using the 2 solvents and leave the ingredient differences to another person.

MS dries faster than the turpentine as a rule. Turpentine has a strong smell that some folks do not like. For cleaning I don't see much difference really. If I see a gallon of turpentine that's cheaper than the MS, guess what? Turp.

Lastly, these solvents I have highlighted as extremely volatile liquids. Be extremely careful of where you store rags and materials to prevent a fire.

later

 

[danmart77]

I have heard that the only meaningful difference between mineral spirits and paint thinner is price.

Turpentine is a different animal.

You won't have any trouble telling the difference between the two when you take a wiff. The lingering smell of the turp could be a meaningful difference for a couple days in your shop.

My mother used turp for her art work during my childhood years and it has a nostalgic effect on me for some reason. I kinda like the smell so that's a consideration.

Looking around the paint store, I've noticed odorless MS on the shelves for a higher price. I can see their use if I was revarnishing a handrail in a house and the customer didn't like the strong odor lingering in a room.

I know that varnish doesn't set up completely when the solvent evaporates. I get that. I use the smell of the solvent and its dry time to decide on my second coating.

Believe me when I say the turpentine will leave a lingering smell in a house that you might want to avoid given you have choices on that one that are-- meaningful

 

[Pop Golden]

I think Mike is the first person to mention finishing up the cleaning of oil based brushes with a light oil coat. To clarify a little further- After cleaning my natural bristle brush with paint thinner I dip my brush in thinned out linseed oil. I thin with turpentine and wipe it down pretty well. After a week the brush will feel a little sticky but not hard. Before use, I soak and clean in MS or turp. Ready to go again. Why the fuss? Some of these brushes are very expensive and you want to keep them in top shape.

Dan, What's the ratio? Never heard of this before, but it sounds like a great idea. I do most of my finishing with shellac and like your method with that brush. NOW. Would that method work with my HVLP guns? The thought has crossed my mind. What do you think? I only blow down shellac.

PS: I love the smell of turpentine. I remember school shop and that smell.

Pop

 

[danmart77]

[FONT=&quot]Dan, What's the ratio? Never heard of this before, but it sounds like a great idea. I do most of my finishing with [/FONT][FONT=&quot]shellac and like your method with that brush. NOW. Would that method work with my HVLP guns? The thought has crossed my mind. What do you think? I only blow down shellac. [/FONT][FONT=&quot]

PS: I love the smell of [/FONT][FONT=&quot]turpentine. I remember school shop and that smell.

Pop

What's the ratio? Depends on what oil and what solvent I'm using at the time and truthfully what looks about right will be fine -- its not rocket science. As a rule I like to keep my turpentine for fresh mixing with my varnishes and oil pigments.

A good rule of thumb is 1 part oil and 2 parts turp or MS works for me. When you get down to it, you just want the bristles to be slippery and you want to have something on the bristle that you can remove when you want to use the brush. I always have linseed oil around so that's what I use. I would imagine there are other oils that would work as well or better but I'm pretty satisfied with linseed. One other oil I keep around for my hands and other things is Mineral Oil. The clear stuff you can find at the drug store. I use this stuff for everything. If my son complains about not having much luck on the throne, a couple tablespoons of Mineral Oil and he's in business again.

You can cut this with Mineral Spirits and keep your oil brush ready.

Pop I don't do a ton of spraying but the spraying I do on wood I do with shellac. I came out of the 60's spraying lacquer on cars with a Binks 7 and who knows what is in my blood stream. The US Air Force said I was Ok for flight duties so I guess it didn't hit the big parts. At 64, I don't go near lacquer without a booth.

Shellac is sooooo easy to maintain and clean I would just soak my tips in alcohol and call it a day. Its that easy.

A useful tip: In the hot weather I like to put a few drops of turpentine in my shellac mix to help slow the dry time(flash) when spraying. It really is nice when I am shooting shellac in this hot weather. Note: this will not solve the blushing on humid days here in the Tar Heel State. You just have to wait.

Hope this answers your questions. A bit long but maybe it will help??

Dan[/FONT]

 

[Mike Davis]

Mineral oil never drys out...


dont tell anybody, but I use 30wt non-detergent.

 

[Danny Batchelor]

Never saw a wt indicator on mineral oil. Maybe I live too far south.

 

[Mike Davis]

Observant...

motor oil is cheap, doesn't dry out, desolves wet oil base paint and varnish, and is usually close at hand.

 

[danmart77]

Mineral oil never drys out...


dont tell anybody, but I use 30wt non-detergent.

Its funny you bring that up Mike I've known some others that use kerosene to store oil brushes. I guess its about the same when it comes to clean up for painting.

That reminds me of the tight wads back on the coast of Maine. They would thin down their used motor oil that they saved in a barrel and paint their cedar shakes or clapboards to keep the wood in shape for the rough winters. Don't know of too many insurance companies that would endorse that but it sure worked while it lasted.

Back to painting. A quick rub down of the hands with MO before painting or varnishing will make cleaning you hands a breeze.

 

[Pop Golden]

hanks Dan. Thanks too for all the other input. There's a lot of info. in this thread. That's what I love about NCWW it's knowledge base is Hugh and the members are always ready to pitch in to help. Is this not a great bunch or what? :eusa_danc

Pop