6.19. Paint

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6.19.01 Motorcycle Repaint Project

This is the first in a series of special projects being done for the GS Resources. It is hoped that this project and others will help you to maintain that prized Suzuki GS, keep it looking in tip-top shape and do it as cheaply as possible.

So, you've had you're bike for 10+ years and the paint job is starting to look a little ratty? Do scratches, dents and peeling topcoat have you down? First, let me say that a motorcycle repaint job is not exceeding difficult. You can get a heck of a nice job done, somewhat inexpensively, just by using spray cans and doing a lot of the work by hand. The key to a great paint job is in carefully prep work, using quality materials and taking your time. There is a bit of a technique to all this, though it isn't that difficult. If you are unsure about starting out directly with your bike pieces, you may want to pick up a piece of scrap metal and practice on that, particularly the paint spraying. This is a low cost project. Notice that I did not say cheap! Materials for this type of project can cost upwards of a $100 but considering that a typical gas tank paint job around here runs $500+, it isn't bad. For that $500 you could buy all the materials, paint all the pieces on your bike and still have lots of money left over for beer.

I've omitted the use of air compressors, buffing wheels, paint guns and the like. Even though I may have all these tools, I wanted to approach this project as a hands-on project. In fact, I repainted my bike following the steps listed here, just to make sure it could be done. This is the economy route. While you may laugh at the thought of using acrylic lacquer spray paint cans, let me assure you that you can do almost as well a job with a spray can as you can with an air compressor and paint gun. You just end up doing a bit more hand work in order to achieve similar results. If money is limited, then this is the way to go.

Did I mention that this involves a lot of hand work? If you don't feel that ambitious, feel free to substitute power tools for hand tools wherever it makes sense. For example, you wouldn't want to go using a bench grinder to take the paint off of your gas tank. You also wouldn't want to do any sanding with gasoline in the tank! Be safe and be sure to read the directions for any of the materials that you are using BEFORE you use them. That grinder may take just a little too much material off too quickly. So choose your tools and methods wisely. If you follow these procedures, you'll have a paint job that anyone would be proud of.

In order to understand everything involved in doing this type of project I'd suggest that you read this article completely before starting. While not extremely difficult, it may still present too big a challenge in terms of time or money. If you don't feel comfortably about this, don't do it. Also, since a lot of the work with plastic pieces involves hand sanding, you may want to find an easier way to remove the paint if you have a bike with a ton of plastic parts. My bike doesn't have a whole lot of plastic when compared to the newer rides but it still involved quite a bit of hand sanding.


Materials Needed

I should state beforehand that I list specific products below. These are simply the products that I have found to be satisfactory for the intended job. While you are free to substitute for other products, the products that I have listed below work well. If you plan on substituting primers and paints make sure that they are compatible with one another. Most paints recommend using a primer from the same company.

The quantities listed below are for a 1981 GS1100. Because later models contain more painted parts, more materials may be needed for your particular motorcycle. You should ensure that you have enough paint and primer to be able to do things continuously, without having to make a trip to the store, especially once the painting and clear coating process is started.

  • (4) 6 oz. cans of Plasti-Kote Automotive Acrylic Lacquer in the color of your choice
  • (4) 6 oz. cans of Plasti-Kote Automotive Acrylic Lacquer Clear TopCoat
  • (2) 6 oz. cans of Plasti-Kote #632, #634, #635 or #636 Automotive Primer
  • (1) pack of 2000 Grit 3M Automotive Wet/Dry Sandpaper
  • (1) pack of 1500 Grit 3M Automotive Wet/Dry Sandpaper
  • (1) pack of 1000 Grit 3M Automotive Wet/Dry Sandpaper
  • (1) pack of 400 Grit 3M Automotive Wet/Dry Sandpaper
  • (1) 3M Perfect-It II Paste Rubbing Compound - Fine Cut, Part #051131, #39002
  • (1) 3M Perfect-It Swirl Mark Remover, Part # 051131, #39009
  • (1) 3M One-Step Finish Restorer/Wax or Meguiar's Gold Class Polish/Wax
  • (1) can of Savogran Heavy Duty SuperStrip paint stripper
  • (1) package of painting tack cloths
  • (1) can of WD40
  • (1) can of lacquer thinner
  • (1) roll of duct tape
  • (1) sharp utility knife
  • (1) roll of 3M Automotive Masking Tape - it has sharp edges and leaves no gum behind
  • (1) 5 gallon bucket for wet sanding parts and a garden hose that can trickle water
  • (1) pair of heavy rubber gloves made for stripping paint
  • (2) 1 1/2" cheap natural bristle paint brushes for stripping paint
  • Bondo body filler for any dents which need to be filled
  • Plastic body filler spreaders
  • Body putty for filling in minor dings and imperfections in the body filler
  • rags (shop rags will do fine)
  • an electric drill with a fine wire wheel attachment for removing rust
  • tools to remove parts from motorcycle
  • a camera, preferably a Polaroid - or digital
  • a scrap piece of 2' x 2' plywood for setting the gas tank on while paint stripping
  • newspapers, wire and anything else needed to secure parts and protect areas while painting
  • a trigger assembly for mounting on spray cans (Your fingers will appreciate it!)
  • a clean space to paint which is well lit and has adequate ventilation
  • if ventilation isn't adequate you may want to purchase a mask that filters out primer and paint fumes. The fumes are harmful.

Most of these materials can be purchased from a full-blown auto parts store like Pep Boys or AutoZone.


Remove parts to be painted

First, get out the Polaroid or digital camera and take pictures of all the pieces that you will be painting. Place a ruler along side the part if you need accurate measurements. Besides being a good source of reference for pin-stripe placement later, it makes good fodder for before and after comparisons. On my motorcycle, the parts removed to be painted consisted of the front fender, headlight housing, gas tank, 2 side covers and the tail piece. Once all the pieces are removed, you will want to remove any parts attached to them, in order to get it down to just the bare piece that needs to be painted. This usually means removing the petcock assembly and fuel gauge from the gas tank and removing all parts from the tail piece. On the side covers, you may have emblems attached using double-sided foam. Squirt WD-40 on the foam, allow a couple of minutes for it to soften up, keeping it continuously wet and pry off using a piece of wood. Avoid prying using metal objects in order to avoid gouging the plastic.


Gas tank preparation

Drain all fuel into a suitable container. Remove the petcock assembly and the fuel gauge from the gas tank, taking care not to bend the sending unit arm. Typically there are a couple of rubber gaskets which are located where the gauge mounts to the tank, so remove these also. Shake out any remaining fuel into a suitable container and set the tank outdoors and allow it to air out for several days. Let it air out until you no longer can smell heavy gasoline fumes. Some people run a hose connected to an air compressor into the tank and let it run for a few hours to hasten this process. Take the duct tape and cover all openings to the gas tank. Use a utility with a new blade to neatly trim the tape. You also want to protect any surfaces where a rubber gasket contacts the gas tank. These areas would be in the filler neck area, the petcock assembly and where the fuel gauge mounts to the tank. This is to prevent stripper and water from entering the tank and to keep these areas paint free.

Gasoline is extremely flammable! Do any gas tank work outdoors until the tank is completely aired out.


Take some more pictures

Examine all surfaces carefully looking for any dings and dents. You need not be concerned about chips in the paint. When dings or dents are found, take a picture of the damaged area. When the pictures are developed, mark the location of the damage on the photo.

The reason for doing this is because once the paint is stripped from pieces like a gas tank, it is extremely difficult to located shallow dents and dings. By recording these locations ahead of time, it will help later in locating these spots. If you are a good artist, you may also want to draw on paper instead of taking pictures.


Paint Removal

This is typically the worst part of the whole job, but by doing this carefully and doing it well, this determines how well the final outcome will be. All remnants of the original paint must be removed!

This is to avoid incompatibilities between the original paint and the new paint you will be applying. This point can not be overemphasized! If you don't remove all the old paint I guarantee it will show in your new paint job!

While I did operations like sanding and buffing by hand, you might be able to save some muscle pain by using a power or air tool. Feel free to substitute tools for hand effort as long as you are sure that it will not damage the part nor harm you. And don't get too aggressive especially with plastic parts. While 50 grit sandpaper takes paint off real quick, you may also destroy the plastic also.

When wet sanding it is important to use plenty of water to avoid clogging up the sandpaper and wearing it out quickly. Keep the area being sanded continuously wet. A garden hose set to a slow drip works quite well. Make sure you have plenty of sandpaper so that it can be replaced as it gets worn out. Sanding parts in a 5 gallon bucket filled with water works good too.

Avoid the use of electrical tools when attempting to wet sand your motorcycle parts. Water is a conductor of electricity and you may seriously hurt/kill yourself if the tool and electricity come in contact with one another.

Plastic Parts Paint Removal

Removing paint from the plastic pieces is the worst part because you can not use paint stripper to remove the paint. Most plastic pieces will melt if any paint strippers are used. Because this is the worst part of this project, you may want to go to your local automotive parts store to see if they carry any products which will safely remove paint without damaging the pieces.

If you do not find a safe method to remove the paint then the only way to remove all the paint is by wet sanding by hand. Fill the 5 gallon bucket with water and wet sand the part using the 400 grit sandpaper to remove all the paint. This will take a lot of time and elbow grease. Change the sandpaper when it gets worn. Rub hard enough to remove the clear coat and paint but don't rub hard enough to create deep scratches in the plastic! When a decal is encountered, simply sand through it.

Once all the paint is sanded off, wet sand the part using a light touch in order to remove any sandpaper scratches. It is not necessary to get a mirror finish but you want to make sure that you do not have any deep scratches. Deep scratches will show in the new paint job particularly with the metal flake paints.

Metal Parts Paint Removal

Removing paint from the metal parts is the easy and fun to watch. That's because the factory clearcoat is pretty tough and the paint stripper really attacks it.

Simply put on the rubber gloves, apply the paint stripper somewhat thick with your cheap paint brush, wait 15 minutes, and rinse it off. When applying the stripper, brush it on going in one direction, once. Do not continually play with it as the solvents will be released prematurely, reducing the effectiveness of the stripper.

Try to avoid getting the stripper on any of the duct tape you applied to block openings. If the paint isn't completely removed with one coat of stripper, apply another. Rinse completely and then promptly dry using a disposable rag in order to prevent the part from rusting. A slight haze of rust can be expected, but will cause no harm.

The Savogran Heavy Duty paint stripper I recommend is some tough stuff. I believe that I had a urethane type clear coat on my gas tank that other strippers would not budge. This stuff will eat through any paint or clearcoat that you put it on. Paint strippers are extremely toxic, caustic and are possibly flammable. Most strippers can not be made non-toxic. Wear adequate hand protection, use in a location of adequate ventilation and ensure that you have lots of water on hand. If any stripper gets on bare skin, wash the affected area immediately with plenty of fresh water. It will burn the skin particularly Savogran Heavy Duty SuperStrip recommended here!

Dent Repair

Now that the paint is removed, chances are that you'll need to repair the dings and dents in your gas tank. Refer to the pictures you took previously. Lightly dry sand the dented area first to help the fillers to stick using the 400 grit sandpaper. If a dent or ding is shallow (less that 1/32 of an inch) use the body putty to fill it, otherwise, use the Bondo body filler. Apply it using a plastic body filler spreader trying to be as neat as possible, but working quickly trying not to play with it too much.. If you're a slob with the Bondo, you'll spend a lot of extra time sanding it smooth.

Once the filler or putty is completely dried, wet sand the area using 400 grit wet/dry sandpaper. Use your fingertips to determine whether it is smooth enough and is following the correct contours. If slight imperfections are detected in the body filler use the body putty to fill them in. Repeat this process until the repair is perfect.

Once all repairs are made, remove any heavy rust using your electric drill with the fine wire brush attachment. When all heavy rust is removed and repairs completed, lightly dry sand all the metal pieces using the 1000 grit sandpaper. This will remove any surface rust which may have appeared by wet sanding..

Painting

Before doing any priming or painting make sure that you read the directions on the spray can. They may have instructions that vary slightly than I have described here, especially in regards to time between coats etc..

I should state that because spray cans are being used and because of a lack of familiarity with painting, you may get some runs. They are almost unavoidable to a certain extent though the wish is that they appear where no one will see them. ;-)

If runs appear in the primer coat, just wet sand the run once the three coats have been applied and are dry. The same goes for runs in the clear coat. If a run appears in the paint coat you may just want to leave it alone until it dries. You may be able blot some of the paint while it is wet if it's a huge run, but I tend to just leave them. The hope is that the clear coat layer will help round out some of it and I will be able to even it up by sanding the clear coat when the spraying is all done and dry.

My experience though has found that a majority of runs happens when spraying the clear coat. Now it's not that I get THAT many runs, but my average is 2 per paint job with cans. As I said earlier, this can be fixed through sanding later so it's usually no big deal.

Applying the Primer Coat

The tedious work is done for the meantime and now it's time for some fun. Lay out the newspapers to protect the floor the area you'll be painting in. The area should be as clean as possible, it should have good lighting, the humidity should be low (below 50% relative humidity), the temperature around 70 degrees F. and plenty of ventilation. Make sure there is no flames around. Lacquer paint does not like to be sprayed when humidity it high and/or it's too cool. Refer to the instructions on the spray cans for specifics.

I tend to like spraying the pieces when hung from wires. I used 12 gauge electrical wire and shape these into a J-shape. This way the parts can be easily positioned and removed from the hooks if necessary. Attach the spray trigger to the primer spray can. You want to spray using light coats to avoid getting runs. What you're trying to achieve is thin, wet looking coats.

Shake the can well before starting to spray and shake the can every 30 seconds during the spraying. This ensures that the contents of the can stay thoroughly mixed. Shoot a couple of shots on a newspaper to make sure that the nozzle is clear. Spray the parts using straight arm movements, overlapping the passes, holding the can approximately 10 to 12 inches from the piece. Be sure to apply sufficient primer to all ridges, seams and welding joints on the piece. Apply 3 coats and allow to dry.

Chances are that the primer coat won't be mirror smooth. Take 1500 grit sandpaper and lightly wet sand the part in order to get it as smooth as possible. If you end up wearing through the primer coat, reprime the piece again. Avoid spot priming - respray the whole piece, followed by a light wet sanding until the piece is smooth. Allow the pieces to dry completely then wipe pieces completely with a clean rag or painting tack cloth.

Applying the Paint Coat

Now that the pieces are primed, you are ready to paint. My philosophy about painting is make sure that you have enough paint to get the parts painted completely in one session (this includes clear coating). Most of the coats need to follow one another in fairly rapid succession so you want to make sure that you have enough time and paint to get it done in one session. If you are unsure, then paint one or two pieces instead of attempting to paint all of them at once. You can also buy 10 cans of paint and return what you don't use. Which ever you choose...

Read the directions to find out what amount of time is recommended between coats. For Plasti-Kote paint they recommend 5 minutes between coats. I typically like to spray 3 coats of paint and 4 coats of clear coat, per piece.

Spray the 1st coat using the same spray methods that you used with the primer. The trick is spraying the paint so that it looks wet and not hazy and keeping the coat thin so that it doesn't run. Make wide sweeps with the can and do not hold the can in one spot. If it still looks hazy, make another wide sweep until the paint looks wet. Spray the part completely, wait the recommended amount of time and respray. Do this until 3 coats are on the piece. As I said earlier, now we continue non-stop to the clear coat section...

Applying the Clear Coat

The pieces must now be given time to get tacky but not completely dry. For Plasti-Kote paints they recommend 1 hour between the paint coat and the applying of the clear coat. Wait the recommended amount of time and spray a light mist coat completely over the piece. Let this sit for 5 minutes and then follow with a regular coat of clear. As I stated earlier that this is typically the easiest coat to put runs into, so you want to make sure that you don't go too slow with your sweeps.

Spray the piece completely, wait 5 minutes and give it another coat. Apply a total 4 coats of clear coat since this is the coat that gives the paint the appearance of depth. Once all coats are applied, allow the piece to dry thoroughly . Because acrylic lacquer paints are extremely sensitive to temperature and humidity you want to make sure that you wait at least a week before rubbing out the pieces. The pieces should be hard to the touch before proceeding onward.

Making 'em Pretty

Now you're probably looking at the piece and you see a couple of cloudy spots and the surface isn't exactly a mirror, right? Well, I didn't steer you wrong. It's now time to invest a bit more elbow grease in order to turn these parts into beauties.

The abrasiveness of the materials that you will be using is as follows.

  • Sandpaper
  • Rubbing Compound
  • Swirl Mark Remover
  • Finishing Wax

Wet sanding again?

If you were careful you should have just slight surface roughness and if you are really good, no runs. Drag out your garden hose and a junk piece of plywood to set the piece on and wet sand all the pieces using 2000 grit wet/dry sandpaper. Pay particular attention that you don't oversand enough to go through the clear coat and/or paint! This is easy to do on pieces that have ridges or edges in them. And don't forget to use a constant stream of water on the piece when sanding. The new lacquer will quickly clog the sandpaper if you don't.

Earlier I mentioned the dreaded word "run". If you find them you should use a 1000 grit to level out the run with the surrounding area. Don't get too aggressive! Use the least amount of aggressiveness necessary, in order to smooth out the surface. When it is level with the surrounding area, switch to a 1500 grit to smooth out the spot even further. Finish off the sanding with the 2000 grit and once done, the piece should feel "as smooth as a baby's behind".

At this point, what looked "not bad" before should look like a cloudy piece of junk. This is intentional. A dull haze, in this case, is one step short of being a mirror finish. You should see no sandpaper marks or surface imperfections once the 2000 grit step has been performed. If you do, go back and do more 2000 grit sanding or if needed, use 1000 grit, followed by 1500 grit and finish again with the 2000 grit.

Rubbing it out

Get a clean, soft shop rag and the 3M Rubbing Compound and start rubbing. The reason I recommend the 3M Rubbing Compound is that it contains no petroleum products or waxes. This is not the standard rubbing compound that you see in short, round containers. This is specially created for smoothing out clearcoats, not remove bugs. Regular rubbing compound contains petroleum also.

If you find that you have to touch up the paint before the wax is applied later, you won't have to strip the piece first before touching up the paint. Not that you'd have to touch up the paint, right?

Start rubbing the paint with the compound trying to rub in one direction only. The reason for this is that you are trying to avoid the creation of circular swirl marks. Circular swirls are the worst because they can be seen from any angle. If you go only in one direction, you'll won't see them unless you are visually lined up in the direction of rubbing. Keep this in mind when you rubbing the piece and trying to determine the direction to rub in.. At this point you should start seeing the gloss that we are trying to achieve. The more you rub the better it will look but you don't want to go too far. The idea with the rubbing compound is to smooth out the surface and as a by product of that, you restore the gloss. Rubbing compound will not remove swill marks (micro-scratches) nor will it protect the finish. That is what the Swirl Mark remover and the wax/polish is meant to remove.

So rub all the pieces, smoothing all the surfaces and restoring the gloss. You don't want to see any scratches, other than light swirl marks, when you are done with the rubbing compound. You can set a bright incandescent light set next to the piece at an angle in order to give you a good idea of how good a job you are doing.

Avoid breathing the dust created when using the rubbing compound. The silica that it contains is a possible carcinogen. Wear a paper mask if you find that you are creating dust.

The Final Step

Depending on how good a job you did with the rubbing compound you may, or may not, have to use swirl mark remover and/or the wax. You may or may not choose to use wax, although I recommend it in order to protect the finish.. An additional reason for using either the 3M Finish Restorer or the Meguiar's Gold Class Polish/Wax is that besides being a protective barrier they also have the ability to remove fine scratches because they also polish. These fine scratches tend to reduce the gloss of the finish besides just making things look unattractive.

The reason that you might want to use the swirl mark remover is that this product has a bit more abrasive for removing swirl marks (micro-scratches). If you do a good job with the rubbing compound, you probably won't have to use this product. I mention it just in case you find that you need something a bit more aggressive than Finishing Wax but not as aggressive as rubbing compound. Try to avoid creating new swirl marks (after all, you're trying to remove them in this step), by maintaining the rubbing in the same direction as you used when using the rubbing compound. Also, be sure to use soft rags and don't be afraid to replace dirty rags with new ones. The use of dirty rags could make a mirror finish elusive at best.

The Finale

If everything worked according to plan, you should have some great looking bike pieces. As you can see, this involves quite a bit of hand work but it should give you a paint job that you can be proud of. Here are a couple of pictures showing you that it is possible to get a finish that you can admire. Trust me, it shinier than it appears in these photos. �� - By Frank Perreault


6.19.02 Paint Removal - Clear Coat

Easy-off oven cleaner - Seems to work great. Cannot leave it on too long or it will etch the aluminum.


BIX paint and varnish stripper - Used this myself. Will not hurt the alum from what I have seen. May take two applications. Neutralizes with water, which makes it easy to work with.


Aircraft Stripper - This is an aerosol spray on stripper. A few said they tried it and it worked well. I checked it out at AutoZone. They sell the Aircraft and another type called Auto Strip that is about a buck cheaper. Both by the same company. I looked at the labels, and they appeared to be the same stuff. Bought the Auto Strip. Must be used outside because fumes are pretty bad. Spray on application is much easier than brushing on. One coat, sit for 15 minutes and hit it with a brass brush. Clear coat gone. Will probably use this on any future stripping in the spring. Neutralizes with water


Lacquer Thinner - Another non-list rider said he strips with lacquer thinner. I would think that is a lot of work because it evaporates so quickly. Probably better for small spots that you might miss with stripper.


Don't forget bead blasting for things that will not get polished. I decided to go with an industrial look for my tracker and bead blasted one of sets of fork tube sliders I have. I think they look better with the satin blasted finish than they do polished.


Rob

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