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Painting questions answered

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Ok, I'm seeing many questions being asked that I've answered before, so I thought I'd try to put them all into one post that can be pinned, tutorial'd or whatever so I don't have to keep searching again LOL!!!!

First, the pro's and con's of paints that I have used.

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In my time of spraying, whether guitars, cars, motorcycles, rc aircraft, or whatever, I have used.......

Component Poly Urethane (PPG, DuPont, RM, etc)

Nitro based laquer

water borne laquer

Enamel

Latex

other acrylic finishes (Createx etc)

Component Epoxy (Endura, Imron)

Now, I have NOT sprayed Poly Ester as I mentioned above, why? for the simple reason that it is harder for me to get, more expensive, and more toxic than all the above mentioned paints except the component epoxy paints.

So, let me give you my pro's and con's with each type of paint.

Component Poly Urethanes:

Pro's: Exceptional flow and levelling,

Very consistent spraying

Very deep finish look when polished

Easy to sand and polish

Full cure in 12 to 24 hours and rock hard

Durable

very good pot life

Con's: Expensive (approximately $100 to $200 a gallon depending on brand)

Toxic, you need better than good ventilation and a very good

respirator.

somewhat time consuming to spray as you wait about 25 minute

between coats (not an issue when doing 6 or so bodies though as by

the time you are done the last, the first is ready to spray again)

Nitro Based Laquer:

Pro's: Inexpensive

Can be sprayed with inexpensive guns or aerosol cans

Very easy to sand and polish

Very deep look when polished

Allows the best movement in wood for acoustic instruments (this also

comes along with a con though)

Con's: VERY long cure time, about 3 weeks before polishing

Continues to shrink almost indefinitely

Requires very good ventilation and mask

Cracks over time (mostly due to wood movement and continued

shrinkage)

Not the most durable

Water borne laquer:

Pro's: Inexpensive

Reasonably non toxic

Water clean up

Easy to polish

Can be sprayed with inexpensive equipment or aerosol

Con's: Does not have the depth of Nitro or Poly's

Not as durable

Takes FOREVER to cure hard (I know this from a neck where brian

refinished a headstock, shipped to me to straighten the neck, and a

good 12 weeks from when he painted it it was still soft enough for

the bubble wrap to leave impressions)

Always seemed to look cloudy to me, never totally clear.

Enamel:

Pro's: Inexpensive

that's really all I can come up with

Con's: seems to remain rubbery for a very long time

Doesnt' really polish well

Long term oxidization and cracking develops

aw hell, just don't use Enamel IMO

Latex:

Pro's: Cheap

Non toxic

sandable

Con's: can be used as a base coat color system, but no clear is available to

my knowledge, must still be cleared with Poly Urethane.

Adhesion can be an issue, this is paint mostly meant for a porous

surface, not the smooth sealed finish of a guitar body.

Acrylic finishes (Createx):

Pro's: Non Toxic

Inexpensive

Water clean up

Easy to spray with airbrush or spray gun

Con's: Clear is not that durable

Paint dries on the tip of the gun very quickly causing clogs

Clear never seems to look "crystal clear"

Adhesion becomes an issue if you do not use proper reducers (water

based does not mean thinned with water, Createx can only be

thinned 20% with water before adhesion becomes a major issue)

Component Epoxy Paints:

Pro's: Extremely durable

Less expensive than Poly Urethanes

Great depth when polished (however see con's below)

Con's: EXTREMELY TOXIC (Imron is the paint equivalent of sour gas, up here

you have to carry certification to spray it, I have certification, and I

still don't spray it) REQUIRES fresh air system/full paint suit/spray

booth

Extremely durable means extremely hard, sanding and polishing is

very difficult

Does not flow as easily as Poly Urethanes.

Basically, the long and short of it is, I've gone to Poly Urethane because of their ease of application, and finished quality. There are many shops still using Poly Urethane, G&L, Fender, GMW Guitar works, etc.

Poly Ester may be becoming industry standard, but it's not what you have to use to attain a professional finish.

Many companies still swear by laquer's.

As with all paints there is a learning curve. The first 5 or so bodies I sprayed with Poly Urethane I had huge runs in because I was still spraying like it was laquer.

The bottom line remains that:

Any paint will work, the end result is up to you though. What I spray, what VH sprays, what anyone sprays, can end up looking like complete crap as well. Professionals use the product that will give THEM the best finish and what is the most accessable to them. There are probably many shops that would still be spraying Nitro laquer except that it is illegal in many states and not available.

A professional finish is based on your application, sanding, and polishing. Not necessarily the product you use. Some products are better than others, there is no denying that. However, the best product used poorly is still worse than the worst product used properly.

Some things to consider:

1. what kind of spray equipment do you have accessable or are you willing to invest in? If you don't have a compressor and spray gun, and aren't wanting to buy them, then the component paints are out.

2. Where are you going to spray it? if your answer is in your basement or garage, I wouldn't recommend component paints either, unless you are prepared to set up a filtered positive pressure spray area.

3. How much do you want to spend on the finish? If you don't want to spend $100, it will be tough to do in component paints, however, one thing to consider. 1 coat of Poly Urethane is equivalent to 2.5 coats of Nitro based Laquer BEFORE shrinking. 10 coats of Poly will be a thicker deeper finish than 30 coats of Nitro after polishing and shrinking.

4. How much sanding and polishing do you want to do? Poly Urethanes will flow out like glass, to the point that if you have a dust free environment you will not need to touch them. Laquers generally always will have some texture to them until they have been sanded out. However, Poly will flow so well, that you can end up with runs in it very easily as well.

5. What is your climate like? If you are in a climate that is very humid, or not consistent, you may not want to spray laquer. High Humidity will cause Laquer to "blush" or cloud. To high a temp (above 75) will cause it to cure on the outer surface to quickly, to low a temp (below 65) will cause an uneven improper cure. This isn't a huge deal, but what it means is more sanding in the end, however, the to fast a cure will lead to cracking. Component paints are MUCH more forgiving in this Realm. On the PPG paints, they say temperature range for spraying is between 40 and 85. Personally, I spray everything at 70 degrees. Humidity can still be an issue for Poly's, but nowhere near as much. What you may see is tiny bubbles in the surface of the poly, this is actually water mist in the paint that rises to the surface as it cures. However, it needs to be VERY humid for that to happen.

7. Assuming you do have spray guns and a compressor, ask yourself this:

a) How big is your spray gun tip? For Poly Urethane, I like 1.4mm. It is a high build paint, and loves to flow. For Laquer, I prefer a slightly smaller tip with less air pressure. If you are spraying with a small gun such as an airbrush, Poly will be tough to spray as you will have to thin it an incredible amount, then runs are more likely.

Do you have proper water traps in your lines? If no, then the same applies to Poly and Laquer as above. I don't recommend spraying with water in your lines anyway, but the Poly will be more capable.

c) Is your compressor big enough to continually keep up a constant air pressure on your gun? I spray at 40psi, when I bought my big gun for Poly's, my original compressor could not fill the tank fast enough for me to spray. Be sure you are getting consistent pressure.

I hope this helps, I guess my true answer is, there is no BEST finish product, only best application.

For me, Poly Urethane is the BEST product because:

- it is easily accesable

- Flows out perfectly

- easy to sand

- looks wonderful when finished

- gives me consistent results on a regular basis.

Doesnt' mean it's the best period, but its' what works for me

Jeremy

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next, some spray gun info and application...

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I've owned HVLP's, gravity feed, syphon feed, airbrushes, you name it LOL!!!!.

My recommendation, is get a small automotive gravity feed gun, something with a 32oz pot is nice. Reason for gravity feed? you use ALL the paint, you don't have to throw away a little bit. With the cost of some paints, you don't want to be tossing anything.

As for a small gun, I recommend the Paasche H series airbrush, they will still do a fairly wide pass with the #5 tip (about 1.5") and can do down to less than 1/16" pass with the #1 tip if you are **** about your paint consistency.

As for the big gun, the big trick is to make sure your compressor will keep up with it, when I upgraded the gun, I didn't have a big enough compressor with my regular one, thankfully I had a second larger one that I am using now.

Look to spend around $125 for an average gravity feed gun, and about $90 to $100 for the airbrush.

I don't recommend ebay for this stuff, you don't want a gun that someone has used, and didn't clean properly. Some of the 2 part paints will not clean out once they've cured. I don't like buying someone else's headache.

The other thing you MUST consider if you don't already have one, is buying a carbon filter respirator.

Laquers are bad, you want a respirator for them, Poly Urethanes are deadly, you HAVE To use a respirator for them. I use a full suit, and generally a fresh air respirator system. You can respray a guitar if you screw up, but you can't rebuild your health once you damage it with that stuff.

Also, if you are going to be spraying laquers or poly urethanes, check your local codes to make sure you aren't breaking any laws spraying in a garage or something. Laquer is fine up here, but I know it is illegal to buy laquer in quite a few states, Poly's are easily bought, but most places require it to be sprayed in a proper filtered booth. Chances are you would never get caught, but all it takes is one upset neighbor with a dead cat

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benefits of a bigger gun

First of all, the larger pot allows you to make sure you don't run out of paint, nothing sucks worse than having to mix a new batch of paint halfway through a job. Plus, if you ever want to do an acoustic, or a neck thru guitar, you will be spread very thin with 4oz. If you are spraying nitro (I hate nitro, and it's probably illegal in Arizona which is why you can't get it, I know it's illegal in Minnesota) you don't want to run out, you don't want to have a coat flash before you get the next on.

The other huge bonus to the 32oz cup, is, I usually mix 12oz and do 2 bodies at once, I lay my bodies flat when I spray, and flip them from front to back. No matter how you do it, you will inevetabley have to tilt the gun forwards at some point, with the larger cup, you can have it half full, and still tip a long way before the paint gets to the top of the cup and gets the lid all sticky.

Also, those little guns are fine, and as Brian told me last night, you can afford to throw them away, but, really, 8 of those little guns, and you've paid for a big one. The big one offers you more versatility. Eventually, I'm sure you'll find more than a guitar you want to spray hehehe.

As for HVLP, they are primarily for industrial use it seems. A couple friends in autobody here bought them for cars, and promplty sold them, they spray the paint on thick, without overspray, but the paint just doesnt' lay out as nice, and requires alot more polishing.

Most companies are using Poly Urethane's now. It's a 2 part automotive clear, it's expensive, about $200 a gallon, but it's worth the money, you'll get about a dozen guitars out of that amount. you can buy less, but it's cheaper to buy a gallon

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Basically there is no secret to a factory finish, just lots of patience, practice and elbow grease.

First step is to make a trip to www.stewmac.com and buy the product Micro Mesh.

Second step is to decide on your clear coat, I use Poly Urethane 2 part automotive clears. (PPG, DuPont, RM etc)

Now, Step 3 is patience, you need to spray and sand. I Spray a few coats (even coverage) on the body, waiting about 30 minutes in between coats, these coats are important to get on fairly thick, or in the next step you'll take off color finish on the corners. So spray them on thick, then let them cure for 24 hours. Start with 600 Grit sandpaper wet with water, DON'T ADD SOAP like some people say. Unless you use only Ivory bar soap, it has no oil in it, anything with an oil in it, you will not get a good finish in the next steps. So, take your sandpaper (block it with a hard block) and sand the body with the 600 until it is totally flat, no runs, no bumps, nothing. There will be little tiny scratches everywhere, thousands of them. Next, take 800 grit and repeat the process. If you had the clear spray out nice, this should only take about 2 hours. If you've got runs, and lots of bumps, more like 4 probably. Careful on all the edges or you'll end up right through your color coat.

Step 4, ok, now your arm is sooooo sore, you won't wanna spray another coat, to bad, we want to get the next coats on withing 36 hours of spraying the first ones. So, I generally spray 3 more "wet" coats on at this point. Then, guess what, you do it all over again, starting with the 600 grit, only this time, after we finish with the 800, we jump to the micromesh, start with the 2400, 3200, 3600 and then 4000. Each time being sure not to change grits until you've taken out all the scratches from the last grit. at 4000, it will be looking pretty good, but not factory. So.........

Step 5, now we spray again, I do 2 coats at this point, only sprayed on a little thinner. Careful, we don't want runs at this stage. You can start with the 2400, and work your way to the 4000 again after these 2 coats.

Step 6, now we've done all our spraying and sanded to 4000 again. Then go after it with the 6000, 8000, and 12,000 grit, you'll want to push hard with the 8000, and 12000, this is more like burnishing than sanding. MAKE SURE ALL THE SCRATCHES FROM PREVIOUS GRITS ARE OUT!!!!!!!! if they aren't, all you'll do is magnify the scratches with the polished coats.

Step 7, ok, last step (hmmmm, and 7? LOL) while you were ordering from stew mac, you can order some swirl remover, I like to apply it with the foam buffing pad you can buy and chuck in your dril. . once you've got it all polished with the swirl remover, leave it sit another 3 or 4 days, then, put your guitar back togehter, and enjoy it.

The process is the same with laquer only you'll end up spraying about 25 coats of laquer, and you want to wait a good 2 weeks before you do your final sanding and polishing, laquer shrinks forever.

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Your post really answered a lot of questions for me.

Edited by Sethmetal

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Oh yeah, what type of paint is in the rattlecans at home depot? I'm using a clear coat rattlecan ....I hope it's not poly.

-Seth

Edited by Sethmetal

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Oh yeah, what type of paint is in the rattlecans at home depot? I'm using a clear coat rattlecan and I've been spraying without a respirator....I hope it's not poly.

-Seth

There are poly urethanes in a rattle can, but not the 2 part types obviously. If it's in a can, it's safer than the 2 part stuff. You can get the 2 part at an automotive paint supplier.

There can be many types of paint found in a rattle can, laquer, single part poly, enamel, latex, the list goes on and on.

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i am finishing my guitar very simply with a black and white design. there are no curves or anything flashy, just straight lines. i have no equipment but at a push could probably get a hold of some. i was just thinking of using car paint in a can. has anyone ever used it? do you have to cut it back between coats? do you then have to laquer over the top? cheers

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nice work as usual jer(whether it's tuts, guitars, bikes, planes....lol) :D

is it posible to paint tuners,tunomatic bridge and a stop tailpiece? Has anyone done this before and how has it turned out?

you'd probably be better off making a new topic for this

hey im redoing my bass is it a bad ideal to use spray paint and then go over with clear coat

no, that's the general idea with refinishing... could you elaborate?

you might want to make a seperate topic too B)

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Jeremy, thank you SO much for putting your wisdom and experience up here. I read the whole thing.

I don't see myself doing much finishing any time soon, but it sure does give me a HUGE appreciation for the time and energy you have invested in researching and practicing your art... your craft. The fact that you're sharing your knowledge makes it all the more incredible, and that shared knowledge will hopefully help some of us avoid some costly and/or frustrating trial and error.

BTW, people, wear a mask when spraying ANYTHING. That stuff goes in your lungs and never comes out.

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i was just going to buy a tin of black satin paint.... i take it thats a no no.

all my bought guitars have this amazing deadly flat surface with zero imperfections, its almost like they are made of plastic. ive varnished and painted a few things in my time but have never reached that level of excellence..... what gives?

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i was just going to buy a tin of black satin paint.... i take it thats a no no.

all my bought guitars have this amazing deadly flat surface with zero imperfections, its almost like they are made of plastic. ive varnished and painted a few things in my time but have never reached that level of excellence..... what gives?

Read this.

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hi, im making my first guitar, and am using zebrano wood. i'd like to do a translucent red finish as similar as possible in colour to the Gibson Cherry Red. Im in :D so might not be able to get hold of all the products you recomend as flamable materials can often not be delivered by air, and some are not available over here, but basically what would you recomend?

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I just painted a guitar with products from my local auto paint supplier with great results - I will post pictures and a step by step after it's all rubbed out and assembled. It the mean time here are a few thoughts that may be helpful:

Find a supplier with helpful salespeople that will spend some time helping you choose the right product, and explaining how to use them. The guy I talked to had painted guitars before.

Paint products that are available in one region may not be available in another, because of local environmental laws, so it is tough to recommend specific products. Im in an urban CA city, and the VOC laws are pretty tough here. Different (more volatile) products are available just by going out of town.

A good (expensive) pro quality clear coat will spray better, dry quicker, rub out better, look better, and be more durable than a cheaper alternative (like a spray can or a bargain clear coat)

When using auto body primer to level the wood, seal the wood first to prevent the primer from soaking in (I used conversion varnish)

Spray in an area that is as free as possible from dust, and curious passers by as possible. (The booth I used was clean, but a shop employee walked into the booth the check out the guitar, and dropped some of his cigarette ash on the still wet clear coat - GRRRR!)

Think safety - Breathing the fumes can case injury or death, so get a good canister mask and use a properly ventilated booth. You don't want to get this stuff on your skin - particularly the catalyzer.

Some people will have you believe that you cannot buy automotive paint in small quantities - this is not the case with the supplier I bought from. They will mix your color to order on the spot in pints - just look through the car color catalogs and pick your color!

I ended up using acrylic paints - a metallic color coat, and a 2-part (conversion) clear coat. The result is stunning, but it was pricey - about $150 for a pint of color, and a quart of clear and the reducer and catalyzer that are required).

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im just a kid who wants to repaint my les paul. it came kinda beatup and id like to do it myself. Whats cheap? what do u recomend for a non toxic cheap clear coat and spray? id b eeeeeternaly grateful to annnnny1 who will help me out. :D shud i make a new topic of this? :D

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[quote]shud i make a new topic of this? [/quote]

You should search the forum and do some reading.

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painting question:

im using nitro cellulose rattle can, black gloss.

after about 8 light coats the guitar was looking great, no depth, but still great! but then after that the coats were coming out with bubbles in a localised area of the body. after sanding them down and respraying the pitting left behind filled up no probs and left no sign of bubbles.... only to have bubbles appear in other areas. the endless cycle began!

ive tried to keep the spray area as clean as possible. could this be caused by contamination? i sanded and prepared this particular area (the front) alot better than the rest of the guitar and wiped it all down with white spirits before spraying.

whats causing the bubbles???

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Maybe the body was still damp from when you sprayed the nitro, and it is evaporating and this is the bubbles rising and pushing the nitro.

This is the 1st time I hear about this, then I have never wiped the body unless it's realy necesary, and I will use naphta, and let it dry completely.

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Your aerosol can has probably almost run out of paint... and is spraying more aerosol than paint onto your guitar, creating the bubbles. I suggest buying another can and not using it more than halfway. :D

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