Underbody Painting
 

Guys,

Amanda and I are doing final detailed cleaning on the underside of the car today in preparation for painting. Here is our plan, please advise if I am doing a step wrong as I want this to hold up and not get caught with any "Oh Sh%t's"

1. Finish clean up to bare metal (all bare metal will be gone over with 50 grit paper to rough it up)
2. Wipe entire underside with water using 3M scourring pads
3. Wipe entire underside with Phosphric acid (let site about 10 minutes keeping area wet to help remove any microscopic rust)
4. Wipe down with water again using 3M pads
5. Wipe down with PPG DX30 wax/degreaser
6. Spray two coats of Omni AU MP176 Etch Primer (PPG Product) Mix a 3 to 1 ratio of MP176 primer to primer catalyst MP177
7. Spray one coat of PPG DP90 Mix 2 to 1 primer and catalyst
8. Seam seal all seams using 3M Ultra Pro seam sealer
9. Spray two coats of PPG DP90 (this is going to be the final topcoat as Amanda likes the color and the paint store said it would be fine as a top coat, true?)
10. Have a bunch of beers and give each other high five's (Beer is only for me :) )


How does this sound to everyone? We hope to finish clean up today and paint first thing tomorrow. I was going to originally spray Eastwood products but they will no longer ship HazMat to Alaska, so I am screwed there. Luckly I have a couple PPG paint stores here.

Thanks,

Bill

I can't help with advice on the prep work, but I can confirm that DP90 all by itself as a topcoat is pretty durable. When I restored my '66 F**d pickup almost a decade ago, the frame was sprayed with DP90 and it still looks as good as the day it was painted. Of course, it doesn't see a lot of bad weather or winter use, but that's probably the case with your car as well.

BWAHAHAHAHAHAA!!!!!!!!!!!!

You don't know where Bill and Amanda LIVE, do you? That's the only kind of weather they HAVE!!!

I'm sure the car will be driven a LOT during the 72-hour-long Alaskan summer. ;)


Chris

I do know where they live; I've been following (and enjoying) the progress on their car for quite a while. And, living in Minnesota I know a thing or two about bad weather...on average, it's colder here in January than it is in Anchorage.

The DP Stuart sprayed 10 years ago was a lot better than the DPLF that is now available. DP was great stuff, but I've had parts show some rust after more than 10 years of indoor storage. I would top coat it with a urethane. You've put so much work into the car so why cut corners hear? There are some "under hood" colors for late model cars that you might use.

John

I'd skip step 5 on pesonal expeience. It sounds like your clean enough and wouldn't want to contaminate the metal with anything that might prevent the etch from being able to react.

Leave out steps 4 and 6.

Regarding step 4 why would you want to put water on a fresh surface that all of the rust has just been killed on? If you are going to wipe it with water and then immediately wipe it with a degreaser/cleaner I suppose it won't hurt anything but I'd leave the water out of it.

On number 6 phosphoric and etch primer are a no no because they are incompatable and you will get lifting later. You can verify this with your PPG supplier. Just shoot it with DP90. Actually you etched it when you put the phosphoric on it so you don't need the etch aspect of the etch primer even if they were compatable.

You need to be very careful about combining metal etchers and etch primer. I missed that the first time I looked at your post. I would use one or the other.

If you use the phosphoric acid, do small areas so you can neutralize and dry before moving on. I use a thoroughly damp rag to neatralize and then follow up with a dry lint free paper towel. Definitely use a good degreaser.

John

Thanks for the info guys. I do not like the idea at all of adding water into the equation. Water and bare metal to me just does not make sense as it would start to flash rust right away I would think.

I really dont like the idea of spraying it down with phosphoric either as it says to keep the area wet for a minimum of 10 minutes to help remove microscopic rust then clean off with water. If we took out steps 2, 3, 4 and 5 would we be okay? My only concern would be that we did not get all the microscopic rust out, will that be a concern of spraying over some rust? Will the rust spread over time?

I will have to investigate Hammered's idea of urethane as I never thought of that and do not know if there will be any compatibility issues. I like the idea though, just dont know how much time I have between the DP primer and then spraying urethane as I do not want to have to "scuff" the paint if it is sitting to long and it is going to take a good day just to seam seal everything. I would like to be able to get this done in two days once step one is complete which will be today.

Thanks for the advice guys. I just dont want to screw up Amanda's car because I sprayed something wrong or in the wrong order.

Bill

I would definitely leave the phosphoric in, as that will convert any microscopic rust to iron oxide, and then clean it with a degreaser to get anything off that will keep the primer from sticking, and then immediately shoot it with epoxy.
As Stuart said you will then have a finish that will outlast you unless you go to the beach a lot.

Using the phosphoric is no big deal. Lay plastic drop cloth on your concrete floor, put old clothes on, put rubber or latex gloves on and goggles, and spray and wipe. I do it on just about everything metal I make or refinish. It kills the rust. It's good stuff.

61-63, Thanks. So am I to understand now do not use any water at all. Use the phosphoric but NOT the Omni etch primer? The car is now in bare metal with some minor clean up in the corners to get some road grim off, but that will only take another couple hours to do. Everything has been gone over with 25-50 grit sanding disks, so the metal is really scratched up. So now that it is roughed up good I am understanding to do the following:

Spray and wipe off wax/degreaser
Spray and wipe off the phosphoric (just spray, let sit and wipe off, no water)
ensure the underside is completly dry
spray two coats of DP90
seam seal
spray one coat of DP90 over the seam sealer and entire underside again
Drink beer...

Thank you for your advise and that of everyone. I would just hate to screw up Amanda's car for my lack of knowledge on painting.

Bill

You got it.

You COULD wipe it down with the cleaner/degreaser again after the phosphoric and I usually do, but it is not required if you got it good and clean before the phosphoric.

That underside will be there from now on.

The DPLF 90 has a 7 day wet-on-wet period although I wouldn't push it this far. I disagree on leaving the 90 on there by itself. I had numerous parts in long-term indoor, but unconditioned storage that were sand blasted and coated with the old DP40 and some top coated with Delstar/Delthane. The Delstar parts looked like new more that 15 years later but the DP'd parts had light rust poking through in a few places.

Do your phosphoric in roughly 2' x 2' sections and you'll be okay. Use a wet rag to neutralize, dry off with an old chamois or paper towels and then blow out the seams before going on to the next section.

John

Guys, Thanks for the great advise and for "holding my hand" on this one. I now have my plan of attack. Just need to get the phosphoric acid then jump in.

John, I like the urethane idea. I take it I can get it at my local PPG dealer. Is there anything I need to look out for or know before I spray it besides the 7 day window on the DP primer and the safety aspect of wearing masks etc? I dont want to have to scuff up the primer as that is a pain in the rear end. I figure I can spray the degreaser/acid/degreaser/two coats of primer/seam seal/one coat of primer then the urethane in three days.

Again, thank you guys for the help and great advise. I know this will help others.

Bill

Post some pictures when you finish.

Bill,

I like to lay the epoxy on fairly wet and usually do two coats unless I need to cut in around things, then I'll do two coats after cutting in. I would still use the DPLF 90 because any missed spots (like inside cavities) will still look presentable after urethane. Seam sealer can usually be top coated within a couple of hours so that shouldn't slow you up. Further, the DP can be top coated within a few hours (read the P sheet) if you only spray one coat (your third coat). I like the 401 hardner because it gives you a little more pot life and is supposed to adhere better, but you need to give it 30 minutes before you spray and it requires longer waits before it can be top coated.

Look at the chip books for late model cars and you'll see some semi-flat blacks called "underhood" colors. I have not used these so ask the rep about them. You typically can't flatten urethanes because they are designed to gloss out so well so these look like a good way to go IMO.

What I would do after the phosphoric:

Day 1, afternoon: shoot 2 coats DP90
Day 2, morning: seam seal (the epoxy will not be so tender at this point), scuff off any nibs or annoyances in DP
Day 2, afternoon: shoot 1 coat DP90 to cover sealer (sealer must be top coatable in this period of time)
Day 3, morning: shoot top coat
Day 3, afternon: drink beer and admire underneath of car.

John

I used Nason two part urethane with PPG flattener and had a hard time getting the flattener right. I ended up scuffing the whole bottom again and recoated with Eastwoods Chassis Black. It turned out great (about 60% gloss). I am not quite sure what their paint is though, it smells like acrylic enamel but they say it has epoxy in it also. How can there be epoxy in enamel or is it a hardener that they add??

Unless you put hardner in the Eastwood paint, it's plain acrylic enamel or lacquer. PPG makes a 50% flat clear (DCU2060) that you can glossen up from there by adding regular clear. That's how I did it which is very expensive. I believe the alternative is to use the underhood paints that I mention in an earlier post. I would go urethane before spraying straight enamel or lacquer.

I lived in Alaska mostly Wasilla for 25 years and they do get nice weather in the summer not real hot just nice. I visted in 03 and it wsas in the 80's on the Kenia and in Anchorage. Fairbanks (went to elementry school there) can occasionaly get in the 90's in the summer but brutal in the winter. Make sure you share the beer with your help. I love Alaska!!!

Eastwood
 

Hammered -- This is off of Eastwoods site, It states it is a modified epoxy, whatever that means.

Not glossy, not dull, just right! Authentic 60-70% gloss looks great on suspension parts and frame. Available in Qts. (covers 40 sq. ft.) and Aerosol (covers 8 sq. ft.). Proper for all makes and models. Tough modified epoxy formulation resists chips, corrosion and temperatures up to 300&186; F; covers fast, up to four times the coverage of similar size Aerosol; average car uses just 3 to 5 cans for entire chassis! (Available in quarts, sprayable only) Works great over bare metal or Eastwood Rust Encapsulator. NOT RECOMMENDED for use over SINGLE STAGE SELF-ETCHING PRIMERS. Buy 3 or more and save

Goatman,

I don't know what a "modified epoxy" is. Generally, there are one and two component epoxies whether you're talking about an adhesive, sealant or coating. One part epoxies usually require elevated temperatures or UV to properly cure.

Nevertheless, you will not get nearly the performance of a good 2K (two component) system with an ambient cure single component coating.

John

Bill you are way too anal. Just skip to step 10.:D

FWIW I've been experimenting with the Eastwood's Chassis black and Extreme Chassis black. I've sprayed over RE and sprayed it straight on bare metal. I also have the primer that they sell but haven't tried it yet.

The regular Chassis black is not that impressive, it just seems kind of soft, it scratches and gouges too easily for my taste.

The Extreme Chassis black seems noticeably harder and more durable. It's more expensive, but when you're only talking about 3-5 spray cans or one big pour can I think it is worth it.

Also - they sell the Extreme Chassis black in 'Satin' and 'High Gloss'. I bought the Satin version, and it's actually pretty danged glossy, about like regular Chassis Black. The High Gloss must be like black ice. :)


Chris

Thanks guys. Shawn, Step 10 is the most important step of them all, how could you think otherwise? :)

Here are a few pictures of the current state of the underside. With some small detailed cleaning in the corners we will be ready to prep-paint-seal-paint this weekend then place the shell back on the frame before the snow hits.

Bill

Bill,

That looks great! Another product you may want to consider is PPG Roadguard. It's a flexible coating that you spray over the DP and then topcoat with urethane. It doesn't go far, so I only used it in my wheel wells. It should reduce the amount of stone chips.

You'll need a conventional gun or a really big tip for your HVLP to spray it.

Looks great Bill;)

Man you got that nice and clean. It ought to look really good when you finish.

Painting
 

OK..1st off...underside looks kick ass!

No mention of Rass-O-Nil or Picklex?

After stripping parts of my car that I will leave bare metal, I coat with any phosphoric acid product. (Just for the derusting and phosphate coating aspect, I have even used concrete cleaner!) I use none of the wash w/ water products. Seems to strange for my education level..

All these guys are right. Do not use etching primers over acid prepped surfaces. PPG calls their etching primer something like Pre Wash (???)

When ready to paint, I will use PPG product to clean metal. Then I use Picklex, Wipe on, wait a min, wipe off. Repeat. Make sure surface is completely dry. I then shoot heavy coat PPG DP90 using HVLP gun. Almost 2 yrs in the most humid garage in all of North Carolina, and no rust showing!.

The underside looks great! Nice job!

Update
 

Just an update to what we have done this weekend. With a starting point of the pictures above what we have done so far is to degrease the entire underside using PPG DX330. Once that was done we used Duponts Kwik Prep 224S then we degreased again with PPG DX 330. After we ensured it was all dry we sprayed two coats of PPG DP90. The attached pictures show just the two coats of primer as it sits now.

Tomorrow we will seam seal it all up with 3M's Ultra Pro seam sealer. Once that is done we will then spray one more good coat of DP90. After the final coat of primer we will then spray with a PPG urethane as a topcoat.

Can someone tell me the mixture for the urethane and reducer to achieve about a 20-30% gloss on the urethane?

Thanks,

Bill

Geez Bill, I have to be honest with you - that looks terrible. You could really use some more practice.

I'll tell you what, I'll do you a favor. You can come down here and practice on mine. No charge.

:bounce:


Chris

Chris,

As long as beer is involved, I am up for the challenge to trying to do better. Send plane ticket and I will see if I can screw yours up as well.

:)

Bill:

If they'd let you stuff your compressor and gun in with your luggage, I'd actually take you up on that. :)

You guys are my motivation to try to stay up to speed on my own car - you are consistently one step ahead of me so far. In fact your chassis turned out so nice I decided to have mine sandblasted as well, officially putting the wire wheel on the shelf for the moment.

Are you going to paint the entire car yourself as well? What color are you guys going with?


Chris

Bill,

That looks great! Did you take a look at the Underhood urethanes I mentioned? They go under the PPG series DBI or DIU. The reducer will not affect the gloss level. Further, you will have little success flattening one of PPG's conventional urethanes.

John

Chris,
Thanks. We are going to paint the car ourselves yes. We are doing everything to this car except rebuilt the rear end (already done), rebuilt the TH400 and the short block 400. No way would I attempt the tranny. I would like to build the block ourselves as Amanda disassembled it before we took it in to get cleaned and fluxed. I just dont know anything about building engines, I do have Jim Hand's book and have read it but dont feel comforatable building it because this will be Amannda's daily driver in the summer and her safety is more important to me then "learning" how to build an engine at this point. I want to and she is begging me for us to build it, just no knowledge level in this area. But hell, we have no knowledge level on anything we have dont thus far, we just jumped in.

John,

The paint store here does not have what you mentioned in stock. However, we did buy today the DCC9300 along with DCX61 hardener and DT870 reducer. Will this be fine for what we are doing? We will be ready to spray this tomorrow night as we are just now finishing up on the seam sealer. I hope to spray the last coat of epoxy and then the urethane tomorrow night with a hour or so in between the two. I have a feeling that this is going to be way to glossy, what do you think? We are going to spray this for the firewall and cowl area as well.

Thanks for the help and advice again.....

Bill

Hey, as far as I am concerned, extra glossy = easier to clean mud, oil and tar off of it later. :)


Chris

Bill,

I think Chris has the right attitude. It will work just fine, but will be high gloss. If you don't like the gloss, you can spend more money and top coat it with DCU2060 Flex-n-Flat Clear. That's what I did and you come back to about the same finish as the DP90. The plain gloss will be more durable and easier to clean however.

I'm looking forward to seeing the final product which ever way you go.

John

John,

Thanks. I just sprayed it........ I will take a picture in a hour or two after the fog clears out and I can see through the mist. WE ARE DONE!!!!!!!!!!!!!!! with the underside that is...

The car looks great Bill!
I'm looking forward to seeing it in person at Norwalk in '06.
You and Amanda are doing a fantastic job.
Jeff

Bill:

What compressor and gun are you using right now??


Chris

Done.........
 

Well.... We are done with the underside. Attached are a few pictures, keep in mind this is still wet. What we did was sprayed one good coat of primer ontop of the 3M seam sealer (that stuff is great....) We let the primer sit for a few minutes then we sprayed two coats of the Black urethane as you can see in the pictures. We did not spray the urethane in the wheel wells as tomorrow night I am doing to spray in a coat of rubberized coating in the well area. Once this is done, we will then prep-prime-seal-prime-urethane the firewall and cowl area then the body goes back on the frame this weekend. I want to thank as always everyones advice on helping us out as we dont know what we are doing, but not affraid to try.

Jeff, If both of us do not see you in Norwalk next year, I will definnetly be there as I already have my kitchen pass for it.

Chris, I used two guns. One is a gravity feed HVLP by Wall Wick with a 1.5 nozzel. The other gun I used is an el-cheapo from Home Depot, I used this one to get into the tight areas etc. It is a conventional gun I paid $29 for. I bought a year ago a Husky (Home Depot) 60 Gal, 11SCFM, 7hp, 240 volt, 2 stage compressor. It works great with all out air tools and sprayers.

Bill

:beerchug: :clap2: :hail: Dang Bill that looks great!!!!!!!!!

Bill,

It must feel awful good to have this done and looking so good. Are you going to spray the DX54 Roadguard in the wheel wells? It may not spray through your HVLP so you should do a test shoot first.

John

Shawn, Thanks. How have you been these days? How is the car coming?

John, Thanks. It is a great feeling to finally see progress. I bought a few months ago and sprayed tonight Eastwoods rubberized undercoating. Man, what a mess. The HVLP did not work and neither did the undercoating jun. So I sprayed as best that I could and rubbed it in with my hands to smooth it out. Not the preiest thing, but worked. Looks okay, but I am happy with it. Just did the rear wheel wells. Tomorrow I plan on doing the steps for the firewall/cowl area and Sunday place the body back on the frame if I can figure out how I am going to do that safely :) Thanks for all the help...

Bill

Well Bill I finally got back to my rear window channel. And I may be the proud owner of a 68 le mans in the morning.Will post pics when I can.;)