JDW'S
"BODYWORK 101"
"I
wrote this article to show how to get excellent results in body work with
simple tools. It's intended to be a guide for the novice body worker trying to
save money, and covers only surface preparation prior to painting.
"Not everybody can afford the big air compressor and special tools associated with this kind of work for what may be a one time job. I'm into my third full restoration and sixth paint job, and still prefer to keep it simple.
"I hope this little piece will help someone because any day I can help
someone is a good day for both of us."
-JDW
- Lesson
1-
In the first picture, the door has been marked with a pencil to help locate
low areas while sanding. Aerosol paint a different color than the primer could
be lightly spritzed on as a guide coat, but at this stage lead pencil marks
work just as well and are quicker (& cheaper).
The sandpaper you see
on the right edge of the door is 180 grit dry production paper wrapped tightly on a ten inch piece of paint
stick. Sanding lightly, using long multi-directional strokes, will point out
high spots as well as low ones. ______________________ The right side of the vehicle had taken a moderate hit in this door, the door jam, and an area of about 18" behind the door. The repairs had been quick and sloppy with lots of "Bondo". So, the job began with removing excess body filler while the door was still installed so it and the area behind could be contoured and fitted at the same time. About 10" of door jam had to be re-fitted to the door with fiberglass reinforced body filler. Reworking a botched job is harder than doing it from scratch. ______________________
JDW's NOTE: When mixing body filler I never use more than half the recommended hardener; the same goes with fiberglass resin. It doesn't matter how little or how much hardener you use, the putty will cure to the same firmness and consistency when thoroughly mixed. Using only a little hardener gives you more time to work and conserves material that would otherwise begin curing before you're finished with it. ______________________ As the filler cures it goes through a heating period and is ready to sand when cool to the touch with the backs of your fingers. I mix filler on discarded snap-on coffee can and plastic ice cream container lids. They get trashed anyway and sometimes you can bend them and, the cured filer pops off so you can reuse them. Besides, they have two useful sides. ______________________ You can get a little better look at the stick sander in the below photo. The 180-grit sandpaper is wrapped tightly around the stick and as you use up a section you tear it off and begin working with the newly exposed paper. You can even sand with the edge of the stick which works real good along the insides of breaks like run the length of these doors. The little wire brush is for cleaning out the 180-paper which fills with residue real fast. Cleaning it every little bit makes it last 10 times longer.
______________________ Aerosol primers are OK for doing small areas and avoiding the mess of mixing for, shooting with, and cleaning up a spray gun. The Sherwin Williams GBP # 988 is the best self etching aerosol primer for bare metal I have ever found. Spray it in a well ventilated area and avoid breathing the fumes. It smells just like DuPont Vari-Prime which is referred to by many professional painters as "Yellow Death". It's hot stuff, so shoot a little, step back, watch which way the overspray drifts, and stay clear of it. You may well ask, "If you know so much about how these so called lethal materials smell; why ain't you dead?" Well, I don't know. Maybe the cigars and cigarettes I smoke protect me from it. Just don't take a chance with your health and stay out of the fumes. ______________________
Color coat painting; that's a whole 'nother story that I'll not get into because I learn every time I do it. That step is something you can do or you can't, there's no in between, and if you think you can't, take it to a pro. ======================
- Lesson 2-
So,
you thought 'jamming' was a group of musicians getting together and trying to
out play one another and having a good time.
Nope! Not when it comes to cars. 'Jambing' a car is somewhat different than 'jamming musicians', and if you call wearing your fingernails down into odd shapes, poking little holes in your fingers and hands, and generally working your fingers to the bone fun, you'll enjoy SANDING JAMB AREAS. Jamb areas are around door jambs, door edges, the bottom of the hood, the engine bay, and all the places that must be jambed-in (painted) before you shoot the overall color coat. It' a major portion of what that two or three grand you drop on a body shop goes for. Most of what you buy is "grunt" work. The actual color coat paint, hardener, reducer, and clear coat, (if you use a two stage system) costs maybe $400.00, depending on color and paint type, and the painter himself spends only about an hour with your car. Before that comes, however, all the grunt work. Well, boys and girls, that's after degreasing and scrubbing all that, sanding the original finish, and priming it to the point you see here. That puts it at no less than eighteen hours multiplied by the body shop rate because most under hood areas easier to work than this one. How much money can you save by doing it yourself? Go figure. Wait, there's more. About all you need for jamb sanding is a couple pieces of 3M # 7447 Scotchbrite pad, some 320 dry paper and maybe a piece of 180 dry paper. Scotchbrite pads seem handier if cut into 3 or 4 pieces.
The Scotch-brite alone works well on most surfaces, but when priming into many of these type areas they'll always be some blow out and stick to surfaces in a nearly dry state. You'll feel where they are as soon as the Scotchbrite hits them, they feel kind of like sandpaper. Grab the 320 give the area a couple of swipes, the nibs are gone, and go over it with the Scotchbrite to retain a uniform surface. If you happen onto a run, you can knock it off quick by finger sanding with the 180 then hit it with the other two. Keep an eye on your fingers when hand sanding, you may want to start off wearing a latex or nitril glove to save wear and tear on yourself. I once wore the skin on my fingers so thin I started bleeding right through it before I knew what was happening, put a latex glove on and kept going. Remember to spot prime any areas where you happen to sand through to metal, let it dry, and Scotchbrite it. The
next step is to wash everything with plain water and powerful stream from a hose
nozzle or pressure washer. This gets rid of all sanding dust, abrasives that
have worn off the sandpaper, and bugs; especially spiders. Those little devils
will take up residence in the tiniest places, so wash them out good, the
hardiest ones will run out onto your paint when you start spraying. I like to
wash everything the afternoon before I intend to paint, stand it up against
something and let it dry overnight. The next morning I'll turn the doors, hood,
etc 90 degrees just in case some water stayed in there somewhere and let
them set while I do my masking and prepare to paint.
______________________ ======================
- Lesson 3- Now, its on to painting the jambs. You can spend all the money you want on tools to paint with, but this is all you need. ______________________
______________________ ______________________ ______________________ Jambing is finished; and, it all turned out quite well. We're coming down to the wire now and one unattended flaw, anything unnoticed is going to stick out like a sore thumb in the finish coat. You've probably noticed by now that I'm a big fan of stick and block sanding. Block sanding is an absolute must at this stage. If you have a rubber sanding block throw it on the floor as hard as you can, see how far it bounces, and don't retrieve it. It'll pick out some flaws, but a hard plastic or wood block will find all of them. A hard block, in conjunction with a guide coat, will pick out every low spot, high spot, sandpaper scratch, pin hole, or paint run no matter how small it is. Rubber sanding blocks cost me 4 times more work than actually needed doing until I learned what works best. On anything except a high spot or pin hole try and see if it will block sand out. If you get into the bottom coat of paint, or metal, and the flaw remains you'll have to skim in some filler or spot putty. Spot putty is actually thick lacquer in a tube, like a toothpaste tube, and is used only for pin holes, sand scratches, and very shallow voids; otherwise use a finishing filler like the Putty-Cote mentioned before. 3M spot putty comes in a monster tube you couldn't use in a lifetime so find some Bondo brand in a smaller tube for about 1/4 the price; same stuff, thick lacquer.
Hey, did ya notice that cool door latch? It's polished and clear coated,
shines like a diamond in a goat's grommet. Pickey, pickey,
pickey.
______________________ I
once had a guy tell me, "I never block sand the final primer, I just palm
sand it. What's wrong with that?" Actually nothing is wrong with that if
you want your finish coat to look like a mirror...in a damned fun house. Block sand it!! Period.
Look
closely at the feather edge effect, (feathering), by this time you have at
least a coat of primer and a guide coat on there. Is the bare metal spot small
or large, like this -O- big around or this l---------l wide, or bigger? Are
the feather edges from metal to one coat to the next this l-l wide or
this l-------l wide? The wider the better on both counts. If you're at
minimums you'll have to tap the spot down, fill it, and start again. Otherwise
give it 4 or 5 coats of primer, aerosol is OK, guide coat it, and palm sand to
a finish.
Back to the knock down with the 240 wet paper. Like I said, 240 is too course for finish work. There's a good chance it will leave some sand scratch that will show in the finish coat so lets eliminate that possibility. Normally I'd have done this step with 400 wet sanding so the next step is to wet palm sand everything with 400. It's OK this time because I know it's flat before I start. Next is to dry it off and pet the whole thing with a 3M # 7447 Scotchbrite pad and we're done
Now
for "color hold-out". "Color hold out" is evenness of
color in the final finish. It's not a problem you have to contend with when
using dark colors or single stage, (no clear coat required), paints because
their pigments are not translucent. When you get into light colored two stage
paints, three stage pearl jobs, or new car paints it gets so critical that
DuPont has 5 shades of primer sealer to deal with this problem.
Even with that, professional painters have to "shoot a color card" which is six or eight different shaded strips on a special paper card, match a stripe to the car, mix the paint, shoot a sample, and check that before doing a panel repair on most any modern car. Occassionally, the paint on some cars can't be matched even when you have the VIN and alternate color paint code. Many cars have up to 6 alternates of one color number; and, sometimes the codes just don't jibe with the car. So, if you want a panel repair to actually match on your late model car take it only to a body shop that has a paint mixing station. Only the best ones do and their "shooters" are the ones who make the big bucks, because they deserve it. ======================
- Lesson 4- Funny thing about bugs in paint: They usually die quick and when you sand them off there's not enough of them left to see. The worst remnants I've ever seen was a small line about the size of 1/16" of an eyelash. I did have one hardy little bastard I stood and cussed for 5 minutes while he bulldozed a gnarly one inch 'J' in my new white fender. ______________________ ______________________
You
have entered a world of sight and sound, feel and smell, where even the
unreasonable seems reasonable. Where all human cogitative thought is
at risk, where finding nothing wrong makes you worry and wonder what you have missed.
You have entered...........The Compulsion Zone.
The
sandpaper is speaking to you in a barely audible yet husky voice that on a
rough surface fades to a whisper as it polishes the surface smooth. You feel
the resistance to movement fade as the surface "comes to you"
before you wash & dry it for another inspection.
A tiny flaw gets a quick skim of spot putty or a shot of primer and you wait, but time drags on so you go onto something else. Time for a test and you push a fingernail into the edge of the putty. Not ready. You smell the primer and the heady fumes are still strong. Still not ready. You run your hand over the surface and feel the smooth perfection of it, bend down and spy across the finish moving this way and that to play the light over it from different directions. Soon the primer or putty is ready to work, but a little differently this time. We're to the point that wet sanding with 400 paper seems heavy handed so we grab a worn out piece of dry 400 off the floor and fold it into thirds, worn side out. Then the stroking, petting, and hoping that this is the last time around for this last piece of a job that you have become part of, and that has absorbed every portion of your soul.
(Tony's Note: Damn! JDW's waxing
poetic. The fumes have finally gotten to him!)
______________________
______________________ At this stage you stand back, admire your work, and feel you're finished prepping; not quite. When you find one of these places, use a piece of dry, worn 400 paper and hand sand over it with an ever-so light touch. The paper will have a light drag to it's feel at the start and when you no longer feel that you run the damp cloth over it again. Repeat this, if necessary, until that surface matches the rest. Lightly stroke the area with the Scotchbrite, blow or wipe off the dust, and you are finished.
I
realize that I'm taking you through steps that others will say are
unnecessary. They may say they do it this way, or that; but, what I'm
putting down in this article are methods I've gleaned from watching a half
dozen different body men work and asking them questions about anything
I haven't seen done before. Any step that can produce a better job is never
wasted.
Oh, I advise not using Plasti-Kote # 391 anti rust primer. It's good stuff, with a lot of solids, but dries rather slow and clogs sandpaper quickly. The Krylon Rust Tough works well, but is rather dark. Both companies market a variety of primers of different colors and compositions. Rustoleum makes excellent paints, but they are not compatible with a lot of other brands/types until they have dried and cured out completely which takes a couple of days. Primers and paints of all kinds retain some of their solvents for a very long time and we'll have more about this near the end of the article. ______________________
Masking is an art within itself and it begins with good automotive grade
masking tape. My preferences are 3M and Clipper, in that order and when
masking to a clean line I always use new tape. Get your tape from an
automotive paint supplier and you can't go wrong on quality, they keep the
right stuff. Clipper and 3M masking tapes have always been light tan in
color, but 3Ms new green tape has become the one of choice and is slowly
replacing their tan across the board.
Don't be tempted to use tape sold by building supply companies nor cheap tape to mask a line in automotive painting. The adhesives in those tapes may not hold an edge against the solvents in automotive paints and bleed by creating a gagged line. Or the adhesives could be converted into a slimy mess or hardened to the point the tape is difficult to remove. Cheap tape is OK for sticking down loose edges of masking paper and such as that, but not for working directly on the finish area. The cheap stuff is used only to stick down loose edges of masking paper, the 3M tapes are used wherever you're making a line on the painted surface. It's OK to use cheap tape on a masking roll rig when covering outward from areas where you have already masked your line.
I masked the lines on the side of the truck with new 1/8" 3M Fine
Line then used roll masking paper with cheap tape to mask out from that
point. I used 1/8" Fine Line so I could mask that gold panel, which
included some tight curves, with one piece of tape. Six curves on each
side were too tight, the tape pulled to the insides of them and I had to
re-do those areas. I re-masked with 3/4" tape, drew in the curves
using a quarter, (an American coin with the value of 1/4 of a dollar), and
cut them with a razor blade. Since this cutting was being done on the
basecoat, cutting the paint wasn't a problem. The following clear coat
filled and sealed the cuts and they are totally non detectable.
Masking a straight line should be pretty simple, but gets less simple
when that line is 16' long. Stick the end of your tape down on the line
you want, unroll a span of tape about 2' long, and move the span down near
the surface. Do not pull the tape tight enough to stretch it, just enough
to get it straight. Sighting squarely on top of the tape to the line you
want lightly press the tape down with your finger in 3 or four
places. Sight the line, lift and reposition the tape if it isn't right,
but if you hit your line rub the tape down more firmly. Pull out a couple
more feet of tape, hold a finger on the previous strip about 6"
behind where you stopped, pull that area back up, re-sight, and stick it
down as before. I don't know about you, but if I don't lift that last
6" of a run I'll get a little rise or swag right at that point. If
you end up having to lift several feet of a line get some help. Have them
hold the end of the tape near the surface and you concentrate on getting
it on the line you want.
When masking a sweeping curve, like the lower panel on the side of an Austin Healey 100, keep about a 1' span of tape between the point that is stuck down and the roll. Get the tape to the line by moving the roll and stroke it down as you go. It takes good eye/hand coordination, but if you've got that it keeps getting easier all the way.
Masking raised letters, such as those on the tailgate in one of the photos
was done with 3/4" 3M green tape to make sure my cut edges didn't
bleed under. At that point the tailgate was copper on it's perimeter
and gold in the middle with the copper being masked. I began by masking
completely across the tops and bottoms of the letters at the edges of
their flat tops. That eliminated having to trim any letter on it's top or
bottom edges. Next the rest of the letters were masked in a manner as to
eliminate all the long line trimming possible and the tape was pushed down
over the curves of the raised portions.
Then I sharpened a pencil, not so much to make it sharp, but to expose a lot of lead. Using the side of the lead, I stroked the edges of the letters to create a line to follow, and cut the letters out with a razor blade. The rest of the gold was then masked, the dark color shot, everything unmasked, and the results are in the photo. The top curves of the gold on the tailgate and the gold in those tight curves near the backs of the doors, on the cab, were done much like the letters were.
When painting a car some paint will always blow into the cracks around the doors, so we must get ready for it by masking anywhere we don't want paint to go to go. Most of what blows into the cracks will be rather thin, but that doesn't matter because the area already has a good coat of paint. What we want to avoid is a garish line anywhere in the door jams or edges and having overspray all over the inside of the door.
When masking in tight areas, you just have to do the best you can. Stick one end of the paper down near the line you want, then stick the other end down, or you may have to work around a curve on the way. Working with a roll of tape in close areas is usually impractical so use as many short pieces as you have to in order to get the job done. You'll soon learn how to avoid making a crooked or jagged edge. It's not always possible to look straight down on the top of the tape while working a close line, but it's much easier to do when you can.
I besieged a masking Guru and he sayeth unto me, "Anywhere you don't want overspray to go has to be masked up good and tight.", so I doneth it from that day forward and life has been good. OK, its all over but the shouting, er, shooting.
At
this point the sanding and masking is all done. The whole vehicle has been
checked and rechecked and it's ready, just a couple more things and the
paint goes on.
First blow compressed air into all the cracks and sweep the entire prepared area with it. I'll go over the whole thing with a rag dampened with water and look for fly specks or any other water soluble contamination. Next comes the Prep-Sol, which is a preparatory solvent made by DuPont. There are several of these solvents under different names from different companies used to remove any oil based contaminates just before painting. The main culprits are: Skin oils from touching your skin or hair and then touching the primed surface, excess oil from aerosol primer from possibly forgetting to shake it up good before beginning to spray, and mysterious crap that just got there somehow. You soak a clean rag with the solvent, and wipe an area with a good wet; not quite a running coat. Let it set a few seconds and wipe it dry, or nearly so, with another clean dry rag. The Prep-Sol will bring any excess oils to the surface and the dry wipe removes them. The solvent should lie in a uniform flat wet coat and if you see any unusual separating or "funny" pattern you have found a heavily contaminated area. Keep wetting and drying that spot until the solvent lies as it should. Give the solvent a few minutes to dry out completely before spraying any paint.
A
word about rags while prepping for paint. They must be absolutely free of
any, even very slight undetectable, traces of oil, wax, silicone, Armor All,
or anything like these. Even rags that have been washed in the same batch
with a contaminated rag are taboo, they have to be cleaner than a cloth
table napkin. Most body shops don't even use cloth rags at this stage and
have opted for paper "wipes", usually lint free ones which
are pretty expensive as paper towels go.
The final step before you start shooting paint and done immediately
before, is to wipe the entire vehicle down with a tack cloth for
automotive painting. A tack cloth is just a small cloth impregnated with a
special tacky substance that makes it a super efficient dust cloth. None
of the "tacky stuff" will stick to the surface but the rag will
pick up all dust, cloth lint, or whatever is there.
Important
note: Be sure you have read and understand every detail in
the instructions of the paint you are using. The containers have
instructions on them, but ask your supplier for a detailed
instruction sheet or sheets.
======================
- Lesson 5-
There are some real fancy ways of mixing paint, but we're going to bring
it down to the basics which is all we really need. There are little
dippers with a hole in the bottom you put paint in and time how long it
takes to run out. There are painter's measuring cups with so many scales
and increments you can't figure out how to use them, and hard telling
what other methods. Then there are good old Folgers coffee cans,
clean 'em out good and let them dry completely.
Mixing ratios: The basecoat I'm using here is mixed
2 parts paint to 1 part reducer (thinner) so I measured a can from
the top of that bottom lip and put 3 marks one inch apart.
You can also mark a paint stick and have it standing in the container as your scale while you are mixing. If you want to mix less use a smaller can or substitute 1/4" or 1/2" for 1" per part as you measure the container. Sometimes you'll run across what looks like a screwy ratio in the instructions because they never use a fraction of a unit in the measuring process. For instance: Your paint requires reducer and hardener in the mix. The ratios given may be something like 6 parts paint, 2 parts reducer, 1 part hardener to 6 parts unreduced paint. They will never have anything like 3 parts paint, 1 part reducer, 1/2 part hardener to 3 parts unreduced paint. Now for that portion that says "1 part hardener to 6 parts unreduced paint". The way we are measuring it just means "1 part hardener", forget the "to 6 parts unreduced paint", our mix will come out right because of the method of mixing we are using. The can with 4 marks is marked incorrectly for what I'm doing and I discarded it, but you've got the idea about easy measuring.
You are quite likely to find some terms
you are unfamiliar with in the instructions, such as:
Pot life: Like Cheech may say to
Chong, "Man this Pot Life is great! Gimme another hit."
No, really, 'pot life' refers to how long the paint is usable. If it has
no hardener the instructions will likely say "Pot life
indefinite", which means you could seal it up in the can, mixed or
unmixed, and keep it as long as you wish. If the paint requires hardener
it will likely say something like, "Pot life 6 hours". In that
case you have 6 hours to use all the mixed paint or dump it out and
clean up the gun. Never pour even the tiniest amount of paint
with hardener added back into the container because it will activate all
the paint it comes in contact with, which is all of it in the can. Even
1/2 ounce of hardener will eventually activate an entire gallon of
paint.
Flash time, or time to flash: This
is the minimum amount of time you must wait before applying another coat
of paint. Longer is OK, even better; shorter is asking for runs or
curtains in the paint. I like to extend flash time by at least a third
then look at the paint and see if it looks right. If it doesn't, I'll
wait longer. Any place that still looks damp isn't ready.
Tape free: The minimum amount of
time you must wait before applying masking tape over the freshly painted
coat. This is important when masking out an area to create a two-tone
paint job. I like to at least double this time, then decide for myself
if it really is ready to tape. This is also a good indicator as to
minimum time before removing masking tape, but I treat this the same, at
least double the time, even wait a couple of hours longer.
Time to delivery: The time it
takes the finished paint job to cure to a state where it can be handled
or used safely; it is by no means fully cured at this stage. If you have
items such as trim and door handles to re-install I suggest waiting no
less than 3 days and I'll wait a week. You can work these items sooner
than that safely, but "I
prefer to wait 'till that paint is harder than the hammers of Hell."
Some every important terms that can spell disaster to all the work we've
done (and, you'll never see them in the instructions) are in the next
segments.
______________________
A paint system consists of all the matched components to go from
primer to finish and the containers in the photo are self explanatory.
The basecoat in this Sherwin Williams 4th Dimension system requires no hardener which is a big advantage. That being you have up to 7 days to apply the clear coat without first scuffing the base to make it stick. I didn't need that window, but had the temperature dropped or the humidity gotten too high for a period of days after the basecoat was on I may have. This is one of the "economy" paint systems, how economical depends on the colors you choose. It is quite easy to use, the instructions are simple, the times between each step of the job are reasonable, it lays out good, and works very well in the environment I was working in. There are other so called "low priced" paint systems, DuPont's Nason series being but one of them.
Economy versus expensive systems: The price of a paint system has
little or nothing to do with how well it works, quality of color,
fineness of finish, or durability. The biggest factor is speed of
usage in a controlled environment such as a paint booth. Speed is the
last priority on the list in an uncontrolled environment.
Body shops sell time, that is their bread and butter, the mark-up on materials is minimal by comparison. The big shops that have a mixing station and professionally designed and built paint booth have specialists in every area of body repair. The "mechanics" get the car first. They do the necessary frame tweaks, panel replacements, and repairs. Next a painter who may or may not be the finish shooter applies the primer, and sends it out to the prep boys. They sand the primer, where and if it needs it, and mask the vehicle in readiness for the finish coat(s). Some of the primers they use require no additional work before applying the finish coat. These guys are fast and efficient and do little masking with tape and paper like we have to. Door jambs are "masked" with an expensive round sponge tape that blocks air flow and doesn't create a line where it's used. Most of the body masking is done with a very thin plastic sheet that holds to the body by static cling and is taped along the line to be painted. Then, it goes into the paint booth and the main "shooter" who earns and average of $1,200.00 per week, so the company wants him turning out as many jobs as possible and thus the working speed and expense of the paint systems they use. When he's finished it goes back to the prep boys for final detailing of the finish, then to the body mechanics for installation of glass, trim, interior, just whatever that job requires to be finished. ______________________
But,
here's what can happen in a home carport. I think its just as
good as what I described above!
There are several factors that can contribute to making a finish coat a dismal failure. Up to this point you've learned how to avoid all of them other than blowing dust and bugs. Bugs will be there or they won't, its just the luck of the draw, but you know how to deal with them. If you noticed the floor in the pictures taken after sanding was finished, you've seen it is washed as clean as it can be made; this helps the dust situation.
Here are 3 more things that can ruin a
job and how to avoid them.
1) Your air hose: If the
air hose gets into your work it can wipe out a small area plumb down
into the primer and cost you a day in dry time and repairing the
damage. Any time you must shoot with the gun above chest high drape
the air hose over your shoulder, across your back, pull it snug with
the other hand, and hold it behind you. You will inadvertently turn
the same direction most of the time while going from side to side on
the car and this will cause the hose to start looping. When you see
this, disconnect the gun and straighten the hose. If you let it go and
a loop flops into your work I can guarantee you'll throw an
unmitigated cuss fit even if you have never uttered an obscenity in
your life. "You'll
be flopping around on the floor, kicking and screaming like a Wal-Mart
brat."
2) Solvent pop: This is the
result of painting over uncured primer and may not show up for weeks.
Our new paints are about as porous as plastic and that's zip, zero,
nada. Nothing gets past it without a lot of force. I won't paint
over a large primer coat that has cured for less than a week nor spot
primer any sooner than 24 hours. This usually doesn't cost any time
because my slow schedule doesn't allow painting any quicker than that.
Here's the scenario: You prime an area and have ants in your pants until you can finish sand it. The paint gun is standing by with the mixture in a can ready to stir, dump in and shoot. You knock out the job in record time and it looks great, the best you've ever done, and it looks great...for a few days, weeks, or even months. Then, one day, you're washing your car and you feel something strange underhand. You dry it off, look, and see nothing wrong. Wait a minute, what was that? You get down at a low angle, move around to shift the light and "What's that?" It's Solvent Pop: thousands of tiny pinpoint bubbles in your paint job. How did they get there? In your rush to get the color coat on you didn't let the solvents escape from the primer. In other words, you didn't let it cure. Those solvents were trapped by the paint, weeped out under it, and the first time the car sat out in the hot sun, the solvents changed to gas, expanded, and blew bubbles under the paint. It could be worse. It could actually lift big sections of paint in which case it would soon peel off.
3) Lift:
This is much akin to solvent pop, but now usually happens between the
basecoat and clear coat. You've seen it a hundred times on mid '80's
and later cars. There are two things that can cause it: clearcoating
before the basecoat has cured enough; and, clearcoating when the
basecoat has cured too much. In re-painting it can be avoided two
ways, wait a little longer for the basecoat to dry or scuff the
basecoat with a Scotchbrite pad before clearcoating. Read the
instructions on the paint to know when you are in the clearcoating
window. It can vary from a few hours up to a week.
Orange peel, dry spray, and
several other problems are the result of not following the
instructions for the paint. You don't just buy some paint and some
thinner, dump it together and shoot any more. Now-a-days you buy a
paint system and use it precisely as the instructions state.
______________________ Countless days of toil and drudgery faded into nothingness as the final coat of paint dried, shrunk, and cured, becoming smoother with very minute. Another Miller and another smoke. I hadn't relaxed like this in days. Why? Because today was the culmination of a labor of love which has been especially stressful. The success of my labors depending entirely on a discipline for which I had to constantly remind myself, "It doesn't have to be slick, just wet, it'll lay out later". I must have repeated that phrase to myself a thousand times doing this final round of painting today. But, today, there she was.
Miracle of miracles, there are no bugs in the paint. A few specs of
dust from the wind getting up while shooting, but the color sanding
will remove them in a jiffy. All conditions except the last two are
controllable by techniques outlined beforehand.
This is the most nearly perfect finish I have ever
put on a vehicle and I couldn't keep my eyes off it as it cured and
laid out.
Now, just a few tips:
1) The paint doesn't have to go on slick, just wet looking; it will 'lay out' (the surface will blend to a finish) later as it cures. 2) Just because a paint gun's instructions say it will hold a full quart doesn't mean you have to put a full quart in it. Fill it to within about 2" of the top so none can get out the cup vent and drip onto your finish coat. After a shot sharply upward or downward check the paint cup for runs down the side. If you see any it means your cup gasket is not sealing properly. Unless paint is simply running out, grab a rag and keep shooting, and start wiping the run off making sure not enough accumulates to drip onto your work. The next time you fill the gun, check the fit of the lid on a top cup gun or if you are using a bottom cup with a clamp type closure just turn the cup around 180 degrees and that may fix the problem. 3) When removing masking tape always wait well past the flash time, maybe 4 times longer, and try to pull the tape back over itself at a 45 degree or lower angle. That will cause the paint bridging from it to the finish to be cut instead of trying to lift.
All that's left now is color sanding, buffing, pin striping, and
undercoating. That is, other than installing the hundreds of
parts and components that have been overhauled, cleaned, painted,
lubricated, refurbished, made ready for use and stored in the
spare room of our basement for over a year.
She'll be a 1981 VW diesel pickup with the turbo-diesel engine and 5-speed tranny along with the dashboard and most of the interior and some exterior parts from an 1984 VW Jetta. There is also a little bit of VW GTI and Dodge Neon thrown into the mix also. She will be quite unique, nothing like her ever before, and never again. Thanks to Pete Cummins she already has a name. Pete christened her the "JETTUP": a Volkswagen pickup built with the heart of a Volkswagen Jetta. ______________________ When I jambed the hood with 2 coats of clear it was horizontal and came out slick as a button. While painting the tailgate I put 2 coats on the inside, 3 on the outside. The outside orange peeled, and the inside is "slicker than greased owl manure". The entire rest of the truck got only two coats of clear and is much smoother than either of these items; in fact I'm not going to sand or buff the dark color along the bottom, it doesn't need it at all.
Ready for this? I screwed up again! The peel on the hood was so
bad I decided to stick sand it with 600 grit wet paper to
knock it down quick, then hand sand with 1500, and buff it.
Big Mistake! That 600 put sand scratch in so deep neither 1500 nor buffing could fix that mess. You absolutely can not remove sand scratch with a buffer and finishing compound; it will only widen and deepen the scratch. I had to trash the rags I'd been using because they had 600 grit abrasive in them from wiping the hood down, wash the hood to make sure it was off of it, and spur the buffing pad to rid it of the "gravel" it had accumulated. Next I stick sanded with 1200 wet paper followed with 1500 hand sanding and buffed it again. Some 600 scratch was still there. Back on it with the 1500 followed by the buffer again and that got it passable.
What I should have done can be explained in pictures 1 and 2,
and is the way I did it on the tailgate. This is pertaining to
color sanding flawed or orange peeled surfaces. Wet stick sand
with no courser than 1200 paper to about the stage you see in
picture 1, notice there is still quite a bit of pitting
from the orange peel showing. Wash the area with plain
water to rid it of any 1200 grit left behind and wet hand sand
it with 1500 to the stage you see in picture 2. Any remaining
pits no larger than half the size of a pin head will be diminished
by the buffer to a state that they are hardly noticeable.
If, however you want a glass like show car finish every bit of
pit and every flaw must be sanded completely out before
buffing.
The hood buffed out pretty good, not perfection, but not half bad
for a carport wannabe body beater. There is an art to buffing.
As you use the buffer keep the following tips in mind and you'll
do OK. 3M # 0611 Imperial Micro-finishing compound and a wool
buffing pad can't be beat for this job. You don't need an
expensive buffer, if you never use one you'll never know the
little difference between them and cheap ones anyway. Most all of
them have 2 speeds, high for sanding, low for buffing.
Always buff at low speed, if you're on high speed and stay on one spot too long or make the wrong move things start happening real fast and you can ruin a job in the blink of an eye. Keep the buffer moving. We are removing paint with wet pumice and a fast moving pad. and the friction causes heat. Stay still too long and the heat will soften the paint, the pad will get hold of it and pull a chunk out; it's called "burning" the paint. Get on an edge wrong, the machine jerks in your hands and you have burned completely through the paint and into the primer before you know anything went wrong. So run the buffer on the low speed and give yourself that extra split second advantage.
Here's how to avoid problems while buffing:
1) wear old "trashed out" clothing. sometimes what that buffer slings on them simply won't wash out, ever. 2) shake up the compound and squirt some on the surface to be buffed, you'll catch on to how much pretty quick. 3) set the buff pad in the compound and smear it around a little, then start blipping the buffer switch and spreading the compound around the general area where you want it. 4) switch the buffer on low speed and start buffing somewhere away from any edges of the part you are working until you get the feel of the machine. Don't force the buffer into the work, it's own weight is all the pressure it needs or should have. Notice that when you hold the main handle up the front of the pad tries to pull it to your left, handle down and the heel pulls it right; secondary handle down and the buffer pushes toward you, up and it pulls away. Make careful note of the relationship of handle movement to buffer reaction and what part of the pad is doing the work. Now for the important part: When you approach an edge that is the "cut off" edge on your right hold the main handle up slightly, keep the right edge of the pad barely over and perpendicular to that edge with the toe edge of the pad spinning off the cut off edge. Never buff onto any edge, always buff off it. If that edge is sticking up like the fender bead on an MGB you'd use the same action except you'd keep the pad off that edge as much as possible. Letting the pad run across any sharp edge will buff all the paint off it in a twinkling. After some practice you'll be able to buff a complete tailgate, small trunk lid, or anything you can reach across without walking all around it. Just practice on a flat area using imaginary lines until you get the gist of it. Your buff pad should be at least very slightly damp, except for one instance explained later.
Now we are buffing right along and as the compound begins to dry
you'll notice it beginning to vanish and a shine emerges. When
this begins observe what is going on very carefully. Normally you
just keep buffing until the compound is gone and the shine is
there, but there is one warning sign to watch for. If you see a
swirl or even a partial one in any part of the buff, compound or
shine, stop immediately. Some drying, but damp, compound has
gathered in a "knot" on the pad and has to be spurred
off before proceeding. "Spurring the pad" is turning the
buffer pad side up, turning it on, and dragging a straight slot
screwdriver across the running pad.
The dried pumice and fur will fly so do it where you can make a big mess and it doesn't matter. In fact this is the best way to clean a wool buffing pad either when finished or before use. Washing them causes the wool to knot up on the ends and you have to spur them before use anyway. Don't worry about hurting the pad, I've used and spurred the same one for 15 years and It's still going strong, You should spur the pad any time the buffer sits idle for more than a couple of minutes.
This may be an exception to the damp pad rule above. I just
discovered this today, the light was getting bad and I'm not sure
it did all of what I think it did, but I think so. I really
believe it worked. When buffing at this stage, with this compound,
and this pad you'll usually get some light buffer swirl marks. Not
like the one I mentioned before, it will be wide, these will be
miniscule and uniform. There is a special fingered sponge pad and
super fine compound 3M calls 'Finesse It' to remove this natural
buffer swirl, but what I did today, by chance, just may remove
natural swirll too.
My pad was dry, but uniform and didn't need to be spurred when I used it on the tailgate for the last time and it seemed to remove the swirl so I tried it on the hood and it looked like worked there too. Maybe it did, I'll find out later. Something else that will hide swirl and eliminate surface haze is 3M # 05977 pink Fill 'n Glaze. This stuff has no wax, silicone, Teflon, or any "wonder drugs", is hand applied and buffed, works very easily, and very well. After buffing my tailgate had a surface haze in an area where in diffused light the color was subdued. I wiped on, wiped off some pink Fill 'n Glaze on about a three inch circle and it looked like it just lit up. It works well on any car finish.
When
choosing colors you'll usually have a definite color in mind, can get the
number, and just buy your paint system with solid information. In this case I
had three toning, paneling, and only general colors for building blocks.
A must when choosing paint is to take the color cards or chip book outdoors in
direct sunlight in order to see the true colors. The fluorescent lighting
in stores will change some colors beyond recognition, especially metallics.
Luck was with me when choosing these colors. The company, Sherwin Williams,
had their colors on "decks" of cards with which I fanned out some
choices, went outside, and chose these three. Being able to hold the three
colors next to each other was a big advantage.
______________________
Pin
striping is the next consideration and there are several points to bear in
mind.
First: You want to end up with accents, not distractions or a "hillbilly" motif. Second: The pin striping should create a tie-in with the interior of the vehicle. Third, and very important in this case: The tape must have the flexibility to conform with curves in the paint design. There are a dozen curves with the radius of a quarter in this job so the tape will have to be narrow, and I am currently researching tri-color designs only 1/8" wide. We'll get into pin striping later as Fall is coming on and I want an ambient temperature of at least 80F to lend flexibility to the tape before applying it. ======================
- Lesson 6-
I
don't know of a new car dealership that undercoats anymore. It's done
mostly by car owners with aerosol products. I have always preferred, used, and
have had excellent results by brushing on plastic roof sealing compound. The
word plastic has nothing to do with the composition of these products, it just
means the form of it can be changed during application. In other words, it's
spread-able. It is also quite messy and difficult to work into tight corners.
The first time I used this was on my new 1962 Studebaker Hawk, which is sitting on my carport, and none of it has ever cracked, chipped off, or failed in any way. Aerosol undercoats are fine and there are a lot of excellent ones on the market. However, even at the thinnest you can smear roof sealing compound on, you'll have three times the protection you can get with an aerosol product. It is unsurpassed in rock chip protection, sound deadening, and corrosion defense. When fully cured in 4 to 6 months, it can be painted.
You'll need a cheap 2" paint or chip brush, rubber gloves, and a
willingness to make a hell of a mess. Be prepared to trash the brush, a few
pair of gloves if they are thin latex, the clothing you wear, and maybe a
little of your hair. What can I say? You just dive in and smear the sealer
around until you get full coverage. Start in the hardest to reach areas
and work in to the easy part, go the other way and you'll end up with more
sealer on you than in the fender well.
Overkill? Maybe. I'm just pickey that way. But, here's the finished product; you decide. John
Dandy
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