CR4 - The Engineer's Place for News and Discussion®

Previous in Forum: Hydro Pneumatic Cylinders   Next in Forum: Heater Tubes
Close

Comments Format:






Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







28 comments
Anonymous Poster #1

How To Dissolve Paint From Spray Guns ?

06/06/2012 7:40 AM

Can anyone advise of an aggressive type of solvent or otherwise to use to dissolve hardened enamel paint ( not 2 pack ) , after an employee forgot to clean out an airless spray gun

the paint was left in the pump and spray gun for a week and is rock hard.

pump and spray gun worth about $ 2400


is there anything better / faster / more effective than prepsol ?

Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
9
Guru
United States - Member - Member Engineering Fields - Electrical Engineering - Electrical Construction

Join Date: Apr 2010
Location: Mid Western USA - The Corn Belt
Posts: 1447
Good Answers: 58
#1

Re: how to dissolve paint from spray guns ?

06/06/2012 8:32 AM

Had this happen to me also - Take the gun apart, valve(s), trigger and remove any plastic/rubber parts and soak the metal parts in acetone.

Do not soak plastic/rubber parts in the acetone. Apply acetone to a rag and wipe these parts down by hand or replace them.

As far as the pump, you will most likely have to take it apart if the paint is "rock hard" as you stated. Soak all the parts until the paint softens up and clean the remaining paint off by hand with an acetone soaked rag.

When you reassemble the pump remember to replace the gaskets with new ones, same for the gun.

You my have to let the parts soak for a couple, three days. When you soak, completely cover the parts and check the acetone level frequently as acetone evaporates quite readily.

Do not use any metal objects in the tiny circuits to unclog them, you will damage the metering (calibration) of the openings.

Use compressed air to help clean tiny openings and orifices. WEAR SAFETY GOGGLES.

If the hose is clogged also, probably easier just to replace it.

This may or may not work for you but it did work for me.

I would have the DA "employee" do the disassembly/cleaning/reassembly but that's just me.

Hope this works for you - Good Luck!

__________________
The first 5 days after a weekend are always the hardest................................
Reply Good Answer (Score 9)
Guru
Hobbies - Fishing - New Member Hobbies - Target Shooting - New Member

Join Date: Apr 2009
Location: USA, Florida
Posts: 1184
Good Answers: 107
#2
In reply to #1

Re: how to dissolve paint from spray guns ?

06/06/2012 8:35 AM

Good Advice !

__________________
An obstacle is something you see when you take your eyes off the goal.
Reply
Guru
United States - Member - Member Engineering Fields - Electrical Engineering - Electrical Construction

Join Date: Apr 2010
Location: Mid Western USA - The Corn Belt
Posts: 1447
Good Answers: 58
#5
In reply to #2

Re: how to dissolve paint from spray guns ?

06/06/2012 8:51 AM

Thanks WJ

__________________
The first 5 days after a weekend are always the hardest................................
Reply Off Topic (Score 5)
Guru
Hobbies - Automotive Performance - New Member Popular Science - Weaponology - New Member

Join Date: Oct 2008
Location: Want to be: 34° 34' 21.60" N, 92° 55' 42.28" W Really am in Arizona
Posts: 29255
Good Answers: 1095
#6
In reply to #5

Re: how to dissolve paint from spray guns ?

06/06/2012 1:12 PM

Very good advice.

Now, we're you cleaning the rig because you forgot, or did you have DA employee who did it?

__________________
Luck comes and goes. Skill is forever.
Reply Off Topic (Score 5)
Guru
United States - Member - Member Engineering Fields - Electrical Engineering - Electrical Construction

Join Date: Apr 2010
Location: Mid Western USA - The Corn Belt
Posts: 1447
Good Answers: 58
#7
In reply to #6

Re: how to dissolve paint from spray guns ?

06/06/2012 1:32 PM

Hey Thanks Lyn.

The DA employee was my then 12 year old son.

You know the routine - "Mike, did you clean the spraygun thoroughly, inside, outside, everything" - "Uhhhh, ya Dad".

In reality, he washed out the paint trough, rinsed off the outside of the pump/trough assembly, hose and gun but never ran the unit to rinse the innards.

My bad, I should have checked myself

Discovered the error almost a month later when I went to use the rig again.

Had Mike do the dissasembly/cleaning/reassembly himself but oversaw the operation this time.

It all worked out in the end

__________________
The first 5 days after a weekend are always the hardest................................
Reply Off Topic (Score 5)
Guru
Hobbies - Automotive Performance - New Member Popular Science - Weaponology - New Member

Join Date: Oct 2008
Location: Want to be: 34° 34' 21.60" N, 92° 55' 42.28" W Really am in Arizona
Posts: 29255
Good Answers: 1095
#8
In reply to #7

Re: how to dissolve paint from spray guns ?

06/06/2012 1:36 PM

Lesson learned by both father and son.

__________________
Luck comes and goes. Skill is forever.
Reply Off Topic (Score 5)
Anonymous Poster #2
#4
In reply to #1

Re: how to dissolve paint from spray guns ?

06/06/2012 8:44 AM

Hey when did you post this? I was first in this thread!

Never mind. I think burning wasnt a good idea but is faster right?

Work is too much distraction when looking at CR4. Should not have worked then ...

Have a good day!

Reply Off Topic (Score 5)
Anonymous Poster #2
#3

Re: how to disolve paint from spray guns ?

06/06/2012 8:39 AM

Make the employee pay for the gun and buy a new one.

Then burn the paint in the gun off and have one for home use.

2400,- bucks? Training for the employee would be advisable!

Reply Off Topic (Score 5)
2
Guru
Hobbies - HAM Radio - New Member United Kingdom - Big Ben - New Member Fans of Old Computers - Altair 8800 - New Member Canada - Member - New Member

Join Date: Jun 2006
Location: Toronto
Posts: 3576
Good Answers: 95
#9

Re: How To Dissolve Paint From Spray Guns ?

06/06/2012 11:09 PM

An even better penetrating solvent is methylene chloride. Buy enough to immerse the sprayer - if you can immerse it. Any coils, switches, plastic seals, etc will be ruined by methylene chloride (as well as by acetone).

A third material is lacquer thinner, not as good as acetone or MC.

Both Acetone and lacquer thinner are very flammable = outdoors, no smoking.

MC is also toxic, = outdoors

__________________
Per Ardua Ad Astra
Reply Good Answer (Score 2)
Commentator

Join Date: Sep 2011
Location: Rhode Island
Posts: 56
Good Answers: 1
#21
In reply to #9

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 7:21 AM

Is there a trade name for Methylene Chloride?

Reply
Guru
Hobbies - HAM Radio - New Member United Kingdom - Big Ben - New Member Fans of Old Computers - Altair 8800 - New Member Canada - Member - New Member

Join Date: Jun 2006
Location: Toronto
Posts: 3576
Good Answers: 95
#22
In reply to #21

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 7:38 AM

Any trade name for Methylene Chloride will be for a compound containing it, such ass paint stripper, which also has wax in it to form a shell to reduce evaporation because Methylene Chloride is very volatile and strippers are painted on.

In terms of effectiveness, Methylene Chloride is best, it does not burn at all, but is a little toxic. Carbon Tetra chloride is also good, also does not burn, chlorform is also good but makes you sleep.

All the others, Acetone, Methyl Ethyl Ketone (MWK) Methyl Isobutyl Ketone (MIBK) lacquer thinners are very flammable, but less toxic.

So none can be used in your garage, basement or anywhere indoors for toxicity or flammability reasons. Once or twice a year some moron in the Toronto metro area uses one of the flammable ones to strip paint or glue etc, and you read about the low pressure explosion, whoomph type, which lifts off the roof and pushes out the walls, and often as not kills the moron, and the house turns into a pile of rubble, often on fire.

__________________
Per Ardua Ad Astra
Reply
Commentator

Join Date: Sep 2011
Location: Rhode Island
Posts: 56
Good Answers: 1
#25
In reply to #22

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 7:56 AM

Thanks for the input Aurizon,

Oddly enough I've used and still use a number of the products you mentioned.

I have been on a mission with no end trying to find a solvent that is user friendly with a tri-fold purpose. 1 to clean the epoxy based floor 2 to remove the diggers made by electric hand truck wheels and the toughest 3 remove the colored styrene streaks made by the hand trucks that get embedded into the floor. We use to use this stuff called blackout but it was making the cleaning staff do just that LOL Since i have taken this position i have tried to go green but you know how that goes.

Again thanks for your response

Reply Off Topic (Score 5)
Guru
Hobbies - HAM Radio - New Member United Kingdom - Big Ben - New Member Fans of Old Computers - Altair 8800 - New Member Canada - Member - New Member

Join Date: Jun 2006
Location: Toronto
Posts: 3576
Good Answers: 95
#27
In reply to #25

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 8:18 AM

For fork lift or other heavy traffic you need a heavily filled 2 part zero solvent epoxy paint. Companies make them for this specific application. Under weight, the load is carried by the high filler load. With low filled 'paints' the basic epoxy carries the weight, and it is mobile under load, like toothpaste = not good enough.

I am not sure how you can prevent transfer, unless you make the surface a little waxy, to impede this transfer and prevent it from being smeared into the floor.

__________________
Per Ardua Ad Astra
Reply
Guru
Engineering Fields - Manufacturing Engineering - Hobbies - Musician - Engineering Fields - Mechanical Engineering - Popular Science - Weaponology -

Join Date: Jun 2007
Location: Eden
Posts: 1127
Good Answers: 32
#28
In reply to #25

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 8:49 AM

Okay, well... based on your tri-fold list, the d-Limonene would be the green route in this case. Industrial concentrations are often used wherever acetone or mineral spirits would normally be used. It does strip paint , as well as tar, asphalt, grease and it is used as a floor cleaner. It does dissolve urethane and styrofoam. Although it can't be considered non-toxic, relative to the others that have been discussed, its toxicity is minimal. Smells a heck of a lot better, too. Its effectiveness is often overlooked, for that very reason. By some, it's reasoned that something that smells good can't possibly be very powerful. Might be worth looking into.

Reply
Guru
United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain - possibly to become "South Scotland" or "Non-Caledonia" from September 2016. Kettle's on.
Posts: 22847
Good Answers: 591
#23
In reply to #21

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 7:50 AM

"Polystrippa" (usual disclaimer).

__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
Reply
Commentator

Join Date: Sep 2011
Location: Rhode Island
Posts: 56
Good Answers: 1
#26
In reply to #23

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 8:09 AM

I'm on it! thanks bud

Reply
Power-User

Join Date: May 2007
Location: Ronan, Montana
Posts: 171
Good Answers: 10
#10

Re: How To Dissolve Paint From Spray Guns ?

06/06/2012 11:18 PM

I had an old friend who used to clean automotive spray guns in carburator cleaner. This included ones that had set for weeks. I remember them as coming out super clean and working perfectly. I don't remember how much he took them apart but I'm fairly sure he disassemnled them as much as possible. He would put hem in a bucket of carb cleaner and let them soak.

__________________
"don't be so open minded that your brain falls out" unknown
Reply
Associate

Join Date: Nov 2007
Posts: 48
Good Answers: 1
#11

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 1:50 AM

Does prepsol contain Methyl Ethyl Ketone? If it doesn't try to find something that does and don't let it evaporate...Clint

__________________
Clintb3252
Reply Score 1 for Good Answer
Guru
Engineering Fields - Manufacturing Engineering - Hobbies - Musician - Engineering Fields - Mechanical Engineering - Popular Science - Weaponology -

Join Date: Jun 2007
Location: Eden
Posts: 1127
Good Answers: 32
#17
In reply to #11

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 8:48 AM

I agree. MEK would do the trick very well. BUT be very careful of those fumes. This is bad stuff. EXTREMELY flammable. The fumes are heavier than air and can collect in any confined pockets. The vapors can even run along the ground, and to an ignition source. Make sure there is no possibility of any sparks or flames. It may be more risk than it's worth.

Concentrated d-Limonene is a much safer alternative.

Reply
Guru
Engineering Fields - Nuclear Engineering - New Member

Join Date: Sep 2009
Location: Louisville, OH
Posts: 749
Good Answers: 15
#18
In reply to #11

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 8:52 AM

The Prepsol I know (a DuPont product?) is for cleaning before painting, and is useless for cleaning hardened paint.

__________________
Lehman57
Reply Score 1 for Good Answer
Guru
Engineering Fields - Manufacturing Engineering - Hobbies - Musician - Engineering Fields - Mechanical Engineering - Popular Science - Weaponology -

Join Date: Jun 2007
Location: Eden
Posts: 1127
Good Answers: 32
#19
In reply to #18

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 8:54 AM

Yeah, I was agreeing with the MEK, not the prepsol.

Reply
Guru

Join Date: Aug 2010
Location: Melbourne, Australia
Posts: 599
Good Answers: 20
#12

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 4:55 AM

Most paint/hardware stores sell a 'brush reviver' which dissolves the paint out of the bristles after it has been allowed to go completely hard.

I would try that

Reply
Power-User

Join Date: Aug 2007
Location: London England.
Posts: 366
Good Answers: 3
#13

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 5:03 AM

Cellulose paint thinner,fill up the paint tank immerse the gun in the tank & leave for a few days,keep trying to break-up the hardened paint and remove any loose paint, keep working the trigger to see if it moves,if it dose strip the gun and again immerse in the tank, if the paint has dried in the hose you can probably kiss that good bye,The ideal way to clean these units is to empty the paint reservoir, stand a can of cleaner in the tank & put the gun in the can and pull the trigger this will circulate, dissolve & thin out the paint then put clean gun cleaner in the tank & circulate again, once you're sure the pipes are clean then strip the gun & clean all the individual parts. I have guns that are 15-20 years old and they look new, as for the employee who left it with paint in make them clean it in their own time.

Bazzer

__________________
When I die I'd like to go peacefully in my sleep like my dad,not shouting and screaming like his passengers.
Reply
Guru

Join Date: Jun 2009
Location: Ontario Canada
Posts: 636
Good Answers: 21
#14

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 7:45 AM

If the acetone does not work get hold of some good quality paint stripper material from most hardware stores and soak the parts in it. These come with different solvents such as MEK, so read the MSDS sheets and use all precautions in handling. most gaskets and soft parts will have to be replaced any way. It can be a daunting task but I have saved some valuable paint equipment using these techniques. It will take some time but in between working on the gun you may get some satisfaction in flogging the employee. ( bad joke)

__________________
The fine line between cuddling and holding one down to prevent escape must be learned
Reply
Anonymous Poster #1
#15
In reply to #14

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 8:00 AM

seriously i think flogging the employee should provide some good all round aerobic exercise for myself.

as a side benefit there is a flow on affect with other employees who become remarkably more punctual and efficient in their work as a result . must be purely coincidence .

.

.

.

.

.

.

.

.

not to be taken as anything but humour people . we do not condone flogging of anyone with any object or tool ( unless said object meets OHS requirements for your state )

Reply Off Topic (Score 5)
2
Guru

Join Date: Dec 2009
Location: Kansas, USA
Posts: 587
Good Answers: 53
#16

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 8:34 AM

KJK/USA it sounds like you handled this well in helping it to be a learning experience for you and your son. John Maxwell says, "experience without reflection is opportunity for learning lost".

My son, who is now 22, was over in China last year for about 7 months. He worked with a camp ministry and ended up doing a lot of fixing, from landscaping, irrigation, hanging doors, etc., and as we were Skypping one morning he said "hey daddy, thanks for all those times you took me to work with you and taught me how to do lots of fixing."

It takes time to do the teaching but if we don't take that time to teach our kids and people at work, we end up doing it all and that just compounds our lives. Plus, we are helping to develope the next generation of citizens to be capable, independent and interdependent as they work with other people.

Our job as dads is not necessarily to teach our kids, and those who we are responsible for at work or in business, how to fix something although that is important, it is to help them learn how to think and approach problems. The technical side has to be there as well but the thinking process is highly critical.

The worst thing that can happen when bad things happen is to pay the price for the lesson but never learn anything from the event.

__________________
One of the greatest discoveries a man makes, one of his great surprises, is to find he can do what he was afraid he couldn't do. Ford, Henry
Reply Good Answer (Score 2)
Guru
Engineering Fields - Nuclear Engineering - New Member

Join Date: Sep 2009
Location: Louisville, OH
Posts: 749
Good Answers: 15
#20
In reply to #16

Re: How To Dissolve Paint From Spray Guns ?

06/07/2012 8:57 AM

Thanks. Good stuff!

__________________
Lehman57
Reply Off Topic (Score 5)
Guru
United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain - possibly to become "South Scotland" or "Non-Caledonia" from September 2016. Kettle's on.
Posts: 22847
Good Answers: 591
#24

Re: How To Dissolve Paint From Spray Guns ?

06/11/2012 7:54 AM

Once a suitable cleaning procedure has been established there are two paperwork tasks to do to bottom-out this item:

  1. Write-up the cleaning procedure into a training package, carry out the training and keep a record of the names of the individuals that have been trained.
  2. Write-up the paint spraying procedure into a training package, carry out the training and keep a record of the names of the individuals that have been trained.

Because it's not so much the intrinsic value of the spraying equipment that is important. It is the value of the use of that equipment within the facility that is important!

__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
Reply
Reply to Forum Thread 28 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Copy to Clipboard

Users who posted comments:

Anonymous Poster (3); aurizon (3); Bazzer Englander (1); Clintb32 (1); facilitiesmgr (1); KJK/USA (3); Lauruz (3); Lehman57 (2); lyn (2); Out of Box Experience (3); PWSlack (2); Randyl (1); roy hammy (1); WAWAUS (1); WJMFIRE (1)

Previous in Forum: Hydro Pneumatic Cylinders   Next in Forum: Heater Tubes

Advertisement