Best way to prep body for paint piece meal...

[prezucha]

Hello,

Our new 510 is painted flat black over the original red.  I do not know if it's only primer or base coat.  It's a crappy job and peeling in places I'm sure due to not good prep work.  Just hiding things...  My question is I want to paint it this summer but want to start prep work now.  I will only be able to do a panel at a time.  I've tested one fender with wet sanding with 220 and the black comes off pretty easy.  I think I could probably use 80 grit to make it faster. I expect to do lots of bondo work but we are not expecting a showroom job as we are relatively new to bodywork and painting.  Just want to try and do best we can.  There is exposed bare metal now where I wet sanded.  Is it reasonable to use a rattle can of primer (maybe Eastwood product - epoxy primer??) and do one panel at a time.  If I use epoxy primer I can then afterwards do bodywork if I understand correctly. Thanks!  Paul

 

Finally figured out photo insert.  Next comment...  P.S.  If the whole car looked like this I might keep it like that! :)

[prezucha]

 

Here is a photo.  I assume two colors of bondo, and black is remaining paint/primer...

[Alchemist]

prezucha,

 

You will need to strip the car down to the bare substrate (metal) because, as you stated, you don't know about the foundation.  Do a panel at a time, metal prep the bare metal, wash it clean and "ALWAYS" wear clean latex gloves when you are preparing the part for paint.  It's just like surgery.  If you want a good, long lasting paint job, everything must be kept clean and kept in a fairly clean environment.

 

 I started learning how to paint in 1967 and had been in the automotive restoration industry for over 30 years doing a plethora of ground up restorations, primarily as a painter, but later also doing bodywork, fabrication and finally as a design engineer on prototypes. 

 

I just wanted to share a little background about myself with you please, so you don't think I'm blowing vapor out my sphincter.

 

 

Thanks!

 

Ernie

[INDY510]

gloss clearcoat that, and call it good .... :cool: .... . maybe leave the doors black, it looks cool with the red wheels and red patina

[DanielC]

This is the most important thing you need to do, and know.  Get the data sheets for the products you use.  Read and understand them.

Buying paint on line is OK, but sometimes a local paint store can be a huge help.

 

I would suggest using an epoxy 2 part primer on the properly cleaned metal.  Most rattlecans are not two part.  If you have to rattlecan, plan on going back to bare metal, before you apply the 2 part epoxy.

 

This I have found.  Rust under body filler, applied to bare metal.  This is what I believe happens when you apply body filler to bare metal.

Almost all body fillers are polyester based.  Polyester resins absorb water from the air, even in low humidity.  And we all know what happens when water is on bare metal, it rusts.

 

I use PPG DPLF epoxy primer.  This primer can be applied to metal cleaned with metal prep.  Not all epoxy primers can.  Read the data sheets for the products you use.  I have also heard a lot of good things about SPI epoxies.  It needs to be pretty warm, to use, minimum temperature of 70 degrees.  I probably will not see those temperatures in Oregon for a few months.

[prezucha]

Thanks Ernie, Indy510 (it does look cool like that!), and DanielC!  I've seen Eastwood has a 2 part epoxy primer in a can.  You somehow pop something that allows them to mix.  I think pretty expensive though.  I do have a spray gun and small compressor.  In my mind I think it's too much trouble to set up just to paint one panel or two but in reality it doesn't take that long.  So I will take the body down as far as I need to to get to a solid base and spray with an epoxy primer.  I do have a shop near here where I have purchased paint before.  They do provide good help knowledge-wise.  Once the epoxy primer is on I can then do body work on top of it, correct?  I do not have a garage when the car can sit out of weather.  I do have a car port but other cars are taking that space up.  If weather decent I could pull one of those out...  Thanks!

[TENDRIL]

 

clearcoat this

[prezucha]

Tendril, it does look cool!  Do all those different colors mean there are thousands of dents on that fender?  How to duplicate this on the whole car ?  :) 

 

It feels relatively smooth with only a few small bumps here and there...

[Alchemist]

prezucha,

 

Since you are in Alameda, if I may suggest you visit Finishmasters Inc., located at 2303 Martin Luther King Jr Way, Oakland, CA  510.836.1364. They're an automotive paint supply distributor carrying the PPG, Dupont paint systems.  Along with other automotive refinishing products.    Ask a knowledgeable counterperson questions and pick up brochures on products suggested or products you might consider using for your project car.  It is advisable to educate yourself as much as possible, looking into products and procedures recommended by anyone.  

 

If you were to continue sanding your car in the same methodology you addressed your fender, you'll most likely to get some semblance of uniformity.

 

FYI - If you do decide to clearcoat the paint material left on the car, you must determine what type of paint it is, e.g., nitro/acrylic lacquer, sythetic/acrylic enamel, urethane, catalyzed, etc., .  

 

The purpose behind determining the type of paint currently on the car is topcoat compatibility.  You cannot just apply any clearcoat, whether non-catlalyzed or catalyzed,  and expect it to work.  It would be great if we could readily do that!  

 

If there is incompatibility, when you hit the painted foundation with a wet coat of clear, you could possibly be in trouble from lifting/wrinkling of the remaining paint.  Then you just wasted money and product and now have to spend more money on stripper/sandpaper etc., to remove "all the paint".  But then again, it could be a finish you might like?!

 

Again, I suggest you learn as much as you can about different products you might consider using.  But initially, find out what type of paint is already on the car.  The people at Finishmasters should be able to assist you in determining what's on it.    

 

Hope this helps - Good luck!

 

Ernie

[Alchemist]

If you used a rigid sanding block, then those are "low spots".

 

Do all those different colors mean there are thousands of dents on that fender?  

 

 

If you use a gloss clearcoat, or any gloss finish paint, it will emphasize all the imperfections of a panel.  You can hide imperfections to a point with the type of paint sheen.  There are different levels of paint sheen - or glossiness - to use when painting.  

 

You have "GLOSS" as I just mentioned, or should you apply a non-reflective "FLAT" paint, an "EGGSHELL or MATTE" finish with a bit of sheen, a "SATIN' or "low luster" with a higher sheen, or a "SEMIGLOSS" paint that has a glossier appearance?

 

I would not recommend a FLAT finish on a car because the flattening agent is so coarse that any wax or unwanted residue is almost impossible to remove without marring the finish, causing one to have to repaint the panel.  I discovered this back in the 70's when I painted my 510's hood flat black and some bird left it's droppings on it.  That "sh!t" don't come off - LOL!!  I repainted the hood again in flat black only to think that if I waxed it, it would offer better protection - WRONG!  The wax would not come off because it was embedded between the flattening agent and I had to scrub really hard to try and get the wax off.  I finally found that a "Matte" finish will give you that same look without the hassle.  

 

Ernie

[prezucha]

Ernie, thanks so much for your input!  I was kind of kidding about leaving the colors and clear coating as someone suggested too.  I think in jest.  I plan to paint the car a solid color, whatever my son wants.  So I think I will block sand the car down to at least what the fender looks like, use an epoxy primer to cover all exposed metal, do body work to the best of my/our ability, prime again with a primer filler, then paint.  We do not expect the paint job or bodywork to be anywhere near perfect.  We just hope it comes out decent.  And thanks for the tip about Finishmasters. I'll take a ride over there to meet them.  Where are you located Ernie?  Cheers!  Paul

[Alchemist]

 

 I was kind of kidding about leaving the colors and clear coating as someone suggested too.  I think in jest. 

 

Ratsun guys are rather unique in their tastes, so one never knows!

 

Used to be in Daly City but moved up to Vallejo for now!  

 

One of our members BustaNut has tentative plans to host another northbay BBQ in San Anselmo April 26th but hasn't been confirmed yet.  Keep a lookout in the "Events" forum for confirmation.  The initial BBQ had a nice turnout and my wife and I enjoyed meeting all that attended.

 

Ernie

[prezucha]

Hi Ernie,

Could I pick your brain for a second?  I have several cars that have need of some body work and paint.  Chips, dings, etc.  I cannot afford the time or money to do a good job now but I want to do something to both make the cars look a bit better but also just to stop rust, etc.  I want to do small, direct repairs without painting whole panels.  That would turn out to painting the whole car.  I have wet sanded one area today on the fender well down to bare metal.  It's about 1/2" wide by 6" long.  I tried to feather from the bare metal to the paint but the thickness of the paint leaves a "ridge line".  I'm not too concerned about having the "repair" invisible but want to do what's best.  I did buy factory color paint in a spray can and in liquid.  Do I mask off the area leaving say 1" around it and using a rattle can primer hit the bare spot feathering out the primer?  And then do the same with the base coat and clear?  Again, I'm not looking for a permanent fix but would like it to look decent and better protect the body.  Thanks in advance for any advice.  If you prefer to do this off-forum, I would be totally up for that.  And if you don't want me asking, please tell me!  Paul

[Alchemist]

Hi Paul,

 

Off forum please.  I do not want to be reprimanded for wasting bandwidth.

 

Thank you for the consideration.

 

Ernie

[Alchemist]

Hi Paul,

 

I sent you a message.  After you sign in, if you take note of the icons to the left of your handle at the top right hand corner of the website, you'll see an envelope which should show you the number of messages you received in your inbox.

 

Ernie

[Alchemist]

Hey Paul,

 

I just logged on just now and got your message .  Didn't receive any other messages you mentioned.  I gave you my contact info in my pm to you.

 

Thanks.

 

Ernie

[Alchemist]

Seems like we're having communication difficulties so I'll post a video I found on YouTube regarding one method of "featheredging" bodywork.  This might help you to get moving along Paul!

 

This method can also be applied to multiple layers of paint.  The theory is the more paint layers of paint, the wider the area you must "featheredge" in order to have a smooth transition from the original panel to the of paint.

 

If you go to YouTube and type in the search bar "featheredge bodywork",  you will find more bodywork/paint related videos .

 

 

Just a word of caution here.

 

The tech in the video is running his DA (dual action) sander at a high rpm, the higher the rpm the faster you need to move - as you see he's doing - otherwise you'll cut down the material faster than you'd like and you will end up having to apply filler to build the area up back to where you can get a level panel.  You'll notice the tech doesn't readily "feel" the repair area.  

 

I like to run the tool at a lower rpm and move a little slower.  I would recommend you stop and check your work every few seconds to see how the panel feels.  I "highly advise" that you wear clean latex gloves when working with bare metal.  You note the tech in the video does not!  Even though you will degrease the area prior to applying primer, I prefer to keep the panel as surgically clean as possible. Once I've started repair I never touch a panel with my bare hands!

 

Here's another video on featheredging:

 

 

 

Hope this helps.

 

Ernie

[Alchemist]

Here's a video "primer" (pun intended LOL!) on common sand paper grits.    Please remember that this video is about this particular shop's most common sandpaper grits!!!  I prefer to use #180 and #220 instead of their #150 and #240 grit - and yes there is a difference when it comes to priming and sand scratch swelling/shrinkage when it dries!  Which is why these grits are made available.  Again, this is my preference coming from my experience.

 

From my experience, sandpaper grits are also determined by the topcoat materials you will be applying.  Some factors dictate sandpaper grits, whether it be aerosol can or air compressor supported spray gun applied, the different types of lacquer, enamel or urethane (solvent base or waterbase).  

 

Hope this helps!

 

Ernie

 

[Alchemist]

Here's a good informational video on priming mistakes.

 

 

 

Thank you.

 

Ernie

[Alchemist]

Here's another good video describing the difference between Epoxy Primer and Self Etching primer.

 

Take note, he does not mention, which I will tell you that Self Etching primer (SEP)  is not to be applied as a coating that you can expect to spray on the car or panel, then wait for a week to months before topcoating.  I've seen some Ratsun projects where the car was sprayed with self-etching primer and exposed to the environment, used to go to car shows, meets etc.,   

 

SEP is porous and will allow moisture thru to the bare metal which eventually will start corrosion.   Do not use fiberglass!   I've seen people apply self-etching primer on fiber-glassed parts.  SEP has acid in it's formulation and you would not want to have to go thru the repair - basically having to replace the part because you cannot remove the acid contamination once it has leeched itself into the fabric.  What happens is the topcoat will blister when the ambient temperature gets warm enough for the acid to start raising.  Then you need to repair the area only to have it blister again and again.

 

Just a word of caution!

 

 

Epoxy primers (2K) are better suited for exposure to the environment.

 

The person in the video mentions something called "1K and 2K" primers.  What he is referring to as a "1K" primer is a "one part" non catalyzed primer.  In general, Spray can primer is usually referred to as a "1K" primer.

 

"2K" primers are "2 part" meaning "primer + hardener" or a catalyzed primer.  This type of primer has a formulated mixture and must be sprayed from a spraygun.

 

Hope this helps.

 

Enjoy the video - 

 

[yellowdatsun]

Hi Ernie,

Could I pick your brain for a second?  I have several cars that have need of some body work and paint.  Chips, dings, etc.  I cannot afford the time or money to do a good job now but I want to do something to both make the cars look a bit better but also just to stop rust, etc.  I want to do small, direct repairs without painting whole panels.  That would turn out to painting the whole car.  I have wet sanded one area today on the fender well down to bare metal.  It's about 1/2" wide by 6" long.  I tried to feather from the bare metal to the paint but the thickness of the paint leaves a "ridge line".  I'm not too concerned about having the "repair" invisible but want to do what's best.  I did buy factory color paint in a spray can and in liquid.  Do I mask off the area leaving say 1" around it and using a rattle can primer hit the bare spot feathering out the primer?  And then do the same with the base coat and clear?  Again, I'm not looking for a permanent fix but would like it to look decent and better protect the body.  Thanks in advance for any advice.  If you prefer to do this off-forum, I would be totally up for that.  And if you don't want me asking, please tell me!  Paul

 

I paint my own cars. I hate it, but I still do it. The reason you're getting those ridges is due to the different layers and as a result, different materials. Paint sticks to different materials in different ways, which is why you get the ridges. You'll find that a "Sealer primer" is your best friend when doing paint work. It creates a boundary layer between what it underneath, and the new paint on top. This stuff works wonders.

 

Second, you don't need an epoxy primer. Does it work, yes, but it's not mandatory. Regular old self etching primers work fine. Or if you are doing small spots just use the sealer primer. No need to go overboard. I use the sealer primer wherever I can because it works so well.

 

Third, spray can paints, while convenient, suck. They don't have the correct hardeners in them, and therefore never set up right. Been there, done that, and regretted it. Because they don't harden properly, any top coats can come out really bad. Your best bet is to just buy a small amount, or mix a small amount for a spray gun. The Harbor Freight guns work just fine. That's what I used on my last 510 and everyone thought the paint was amazing.

 

Fourth, when doing small dings, it is sometimes easiest to paint the whole panel. Whether it be a fender, door, or whatever. If you do just paint a spot, it can be really hard to get everything to match, and the sanding and buffing required to make it work is tough.

[prezucha]

Thanks YellowDatsun!  Great tips!  Love to see your car!  Paul

[MantisX620]

Very informative post! Ive concluded that I hate bodywork but will forgo because I want my truck to look nice.

[yellowdatsun]

This was done using a Harbor Freight gun, in my 1 car garage. Keep in mind the paint was never buffed, that's just how nice it laid down by itself.

 

 

 

[freetheoranges]

Yellow, what brand of paint did you go with for that?