Maintaining the paintwork
and the aluminum.
Repairing fairings; maintaining plastic visors;
windshields, repairing luggage.
©
copyright, 2012, R. Fleischer
alcorr.htm-44
See also article #75
How
to drill plastics:
It's true that Lexan, and some polycarbonates in general, are
relatively easy to drill, as opposed to such as Lucite Acrylic,
etc.
Some of the secrets to drilling and avoiding sudden grabbing and cracks from the
drill bit on plastics are:
1. Hand sharpen the drill for very little angle to the cutting edges
with reference to 90° to the shank. Do this so the drill will not try to take a huge bite.....OR, purchase specialty drill bits. NOTE!...Truly proper
"plastics" drill bits have a sharp point of very small diameter, in a
steep triangle shape, that does not travel down the drill shank hardly at all,
and just past that point is the rest of the drilling area, that makes the final hole size,
and THAT portion has hardly
much of an angle downwards at all....perhaps more like 120 degrees or so (90
degrees would be referenced to the shank). This means that the drill has a
very tiny 'tit' to start the hole or align the drill to an existing tiny
hole...and then the end of the drill that does the cutting is very broad....it
almost acts like a spot-face or end mill...with a bit more angle.
I have very successfully used small centering drill bits,
the type used by machinists, to drill holes and even countersink
them at the same time, in plastics.
2. One of the big secrets is to drill a very small pilot hole first.
The second secret is to use a drill bit with maybe 120 degrees or
so for the primary cutting area, as described above.
3. Use a SLOW drill speed, and don't use much pressure. Drill a
small amount, then stop. Repeat. NEVER allow the drill or material
being drilled to get hot. Do NOT try to drill the material fast.
4. Larger holes, 3/8 up: consider the use of a spot-face type of
tool...which has a small drill bit at the center, and 90 degree cutting
surfaces. That is, this looks like a milling tool, with a center
drill in it.
5. When you drill plastics, you usually want the hole to
last forever, and not encourage cracks! In some situations, a small countersinking, often done with a hand
tool, on the two sides of the drilled surface, will 'break' the sharp edges.
DO NOT do this edge breaking with a common larger drill bit...you WILL leave
microscopic weak areas. There is a plastics type of burr tool
for this, but you don't really need it. What you want to end up with is a very
smooth hole with just barely SMOOTHED edges...no sharp microscopic nicks!
The strength of the area to avoid cracks...and FUTURE cracks!....
is greatly enhanced by doing all this carefully. I
have actually shaped a wooden dowel...or even a pencil...and used
a tiny piece of 360 grit sandpaper, by hand, to remove these
hard-to-see nicks after drilling. This
results in a vastly better hole, which resists cracks. Years ago,
when such was available, I used the abrasive typewriter-eraser-pencils, shaped
for small holes, for a finishing polish.
Hints!! for
cleaning windshields, face shields, etc:
Don't use paper
towels. They WILL scratch plastics. Don't use Windex!
Use nothing
with ammonia in it! Some chemicals will cloud plastics, and
start doing it suddenly, after seeming to be fine. NEVER clean or polish
plastics you are going to look through in a circular motion....the swirl marks
will drive you nuts when riding into a setting sun. SOME folks,
including ME, use
vertical movements on the outside, horizontal on the inside....so they can see what you
are doing; others use just one or the other on both sides. Use a
water dampened cloth over the plastic to soften bugs before removal...even if it
takes overnight. Many products are available to clean and then
polish/wax plastics. SEE MY CHEMICALS ARTICLE FOR MY
RECOMMENDATIONS!
click! Don't use coarse
products, don't use petroleum products. If the plastic is scratched badly,
the process to remove the deep scratches is VERY laborious. Removal
of sticky emblems are USUALLY best done with slight heat from a hair dryer (be
careful!), and peeling them off SLOWLY as you apply the heat to the edge you are
gently pulling on. Residues are tricky to remove without injuring
the plastic. I usually use alcohol on a rag, and only briefly. The
old motorcyclist's standby for windshields, to fill in exceptionally fine
scratches, and to leave a bit of protection on the surface, is Johnson's Pledge.
It works OK, but is not necessarily safe for all plastics, and for sure is only
for the finest scratches. SOME plastics will be damaged by such as
Rain-X, so be cautious. An old trick is to use a
cloth dampened with common household vinegar, to help condition
the plastic; and helps considerably with bugs removal chemically.
Some have used WD40 for bug removal.
NOTE!....many plastic windshields have a very thin bonded plastic
layer on the outside. This layer can get damaged over time,
and when it does, often from use of wrong chemicals on the
windshield, you will see large areas where it has disappeared.
The edges are very pronounced.
Paintwork:
To protect the paintwork, one simply does a very thorough washing with any
good auto-parts store concentrated soap in the bucket. Dish
detergents are rather harsh, and I do not recommend them unless you have a
super grungy bike, then you want to first use something like Gunk or Kerosene (I
have added detergents to the kerosene at times), etc...and then wash with
detergents, etc. Please do not use petroleum
products on the paintwork, unless you have no choice. Try
auto-parts stores liquid soap and water first, then kitchen
detergents if you have to. Once properly cleaned and washed, a REGULAR
coating of wax on the paintwork; and also treating the seat and any
fairing, rubber bits, etc. with the appropriate stuff;...all
are needed,,,,....all
are time consuming...but will then last a long time between regular mild
auto-parts store type of soap
washings. That type of soap does not remove waxes like
the kitchen detergents do.
Don't wash the bike when it is hot from riding.
*****Be CAREFUL not to get
water into the transmission and driveshaft....no strong water sprays at the
speedometer cable junction hollow bolt, located at the right rear of the transmission.
Be SURE that rubber boot over the speedometer cable is in good condition, and I highly recommend one
clean the top area of the boot and the cable and then seal with black RTV the junction of the
speedometer cable as it goes into the boot at the top of the boot.
Some use grease inside the boot. Some do both.
That boot tends to deteriorate from sunlight. A coating of
Armor-all, or something that protects from UV rays, on the boot,
AFTER you seal the top and it has dried, is a GOOD idea.
Be sure to grease and oil the necessary items on the bike after washing and
drying. Do NOT forget to oil the barrel ends of the throttle cables at
the carburetor levers....and at the control levers.....
After EVERY wash job!!!
The aluminum:
UNfortunately, there are no good practical chemical methods of cleaning BADLY corroded bike aluminum. Even lightly discolorations are hard to properly remove. One of the problems is the type of alloy used on the cases. The exposure to salt air really makes a mess of the cases, cylinders, heads.....etc. Frankly, the spray stuff for magnesium wheels, or any other wheel cleaner....I've tested plenty of them years ago and reported on them....are not very effective...UNLESS the wheels already look nice.
The etching-type of wheel cleaners, screen door cleaners, etc., will help with the process of cleaning off aluminum and magnesium corrosion, but never let the stuff dry on the bike...always flush before it dries.
Brake dust on the cast wheels can
be difficult to remove. The best method I know of is
not some magnesium
wheel cleaner spray from the auto-parts store, but a mixture
of common household baking soda and dish detergent....and then add a
FEW drops
of water. This thick mixture works fine with old toothbrushes.
VERY THICK syrup consistency is correct. Wash
off VERY thoroughly when you are done. In between serious cleaning of
that sort, you might consider an old coffee-pot type of kitchen brush, many auto-parts stores stock various types of long roundish brushes too, especially
for use on wheels, used with
your normal washing mixture.
Some folks DO use magnesium wheel cleaners from the auto-parts
stores and aluminum cleaners from hardware stores. There
are two basic types, one a silicate, one an acid. SOME
work better than others, but do not allow ANY of them to DRY on the wheels!
Keep in mind that the brake pad dust is cleanable with the
mild and faintly abrasive
soda-detergent-water mixture, but using strong cleaners on
the wheels does not work well, in particular if the wheels
are COATED.
I have found that these commercial chemical wheel cleaners often DO help, some, once the wheels are cleaned with detergent and water and maybe the soda mixture first....if the bike is washed relatively often. The BMW snowflakes have a clear coating which gets chipped at the rim, due to not being careful with metal tools ...that is...not using a bit of plastic or some-such, to protect the rim when doing tire changes....ETC. Once the coating is disturbed, the wheel is more vulnerable. The coating can be touched up....most folks seem to just keep the cleaning process going. Use of Simple Green WILL help some, either full strength or diluted 50%, but do not let it stay in contact for very long, and keep it wet. It is OK to leave it in contact far longer than the commercial magnesium cleaners and aluminum cleaners. AVOID using etching cleaners on clear-coated wheels.
The barrels, cases, covers, etc., are a big problem in salt air. How you deal with this is a matter of how much labor you are willing to provide. Aluminum is not the same as iron, when it comes to oxidation versus rusting. There are also several types of aluminum in use on the Airheads. Aluminum tends to be somewhat self-protecting once the surface looks awful enough. To clean it up really nicely, you need abrasive methods. This means you will use such things as:
1. 3M, Scotchbrite, or similar, abrasive pads. The best are the industrial pads,1/4" or so thick, about 6" square pads, etc. Both the kitchen and the industrial types are available as more abrasive and less abrasive. The kitchen types that are blue are generally much less effective than the green pads.
2. BRASS, as well as aluminum, scouring pads. These are available everyplace as rolled-up/tied-up puffs of kitchen pot scrubbing things. A supermarket item. Brass scouring pads are quite effective, safe too. I use BRASS gun-cleaning brushes to get into the cylinder and cylinder head fins areas.
I recommend AGAINST any type of 'steel wool'....which tend to leave teeny bits of steel in the aluminum....which RUST!
3. Simichrompoli, or other compounds...(takes a tremendous
amount of labor for these)....does polish aluminum alloys....but you CAN end up with highly
polished aluminum, if that is what you are after.
Some types of aluminum staining is removable with this type
of stuff.
4.
In some areas, you can use power tools...with brushes and abrasive compounds
and 3M pad pieces....all sorts of inventive ways of doing things.
You can use brass brushes of the type used for cleaning gun
barrels. I also use stainless steel brushes. I
have quite a collection of various types and shapes of metal
brushes, and I am NOT a fanatic about maintaining a bike to
showroom condition....because I do NOT, NOT EVER. BUT,
I know what works for that.
Common supermarket-sold kitchen and laundry abrasive pads have blue or green
abrasive on one side, the coarser, green, have particles in the plastic
abrasive material, and work fine on aluminum.
5.
Whatever methods you use, you will probably spend a lot of time at it, perhaps
some every week, until you get the effect you want,
particularly if your bike is already
badly corroded. Then comes the problem of
how to maintain it all. If you do a regular cleaning with
perhaps a modest grit 3M pad during the regular washing, that does fairly
well. Some folks purchase some 'chrome' or 'aluminum'
paint...and use some of that paint onto one of the 3M pads, to work the paint
into the surface,
after very thorough cleaning and drying of course, and then carefully wipe the surface to
leave only some paint in
the pores. This really does work well, but changes the color a
bit (there are various colors in these 'aluminum' or 'chrome'
paint products)....more than a bit if you are overgenerous with the paint and not removing
enough from the surface. The paint really WILL reduce the salt air
corrosion by a big bunch... if used AFTER the surface is
properly cleaned up. The use of such paints also makes for easier cleaning of
the bike when washing it.
It is impractical, and results will be very irregular, to use such
things as anodization and other treatments for aluminum, on our airheads.
It is a matter of the alloys.
6. I want to WARN you about 'sandblasting' with glass beads or sand or commercial hard blasting media. This is quite often done during a top end job. The grit gets into everyplace, even imbedding in the surfaces of the aluminum...and gets everywhere's even when masked off. You never seem to be able to get it all out of important places. It may then get into the cylinder, rings, pistons....and your oil supply. Likely OK media: Walnut shells are a bit iffy; soda and CO2 are good. Frozen Carbon Dioxide is probably the very safest.
Luggage Painting and LUGGAGE Crack Repair:
You can sand the luggage and
repaint it. Common rattle-cans of truck bed liner
paint work well, and may be available in more than basic
black. When the luggage has cracks or has
other damage you need to repair (new hard bags are VERY
pricey!), ONE secret is to go to the hardware store and get a
can of ABS pipe cement; black is certainly available. If the repair requires filling in areas,
then
you can get white or black ABS sticks from SOME hobby stores (see URL below
for other ideas), and dissolve shavings or shavings from some old ABS pipe, in
such as Methylene Chloride....nasty stuff, so keep it off your body and do the
work outside so you don't get exposed much to breathing in the
fumes. If you need to fill areas, use that dissolved ABS material,
dissolved to the point it is quite thick....it will dry very quickly after you
force it into holes, fill wide cracks, even add sections. You can
use aluminum foil or some plastic films, temporarily, to provide backing.
Here is a hyperlink to an article with more details:
http://www.webbikeworld.com/Motorcycle-technical-articles/repairing-abs-bags.htm
THINK before doing something!!!
Repairing Fairings, a PRACTICAL
method:
If
you are careful, you can do a job that looks and acts like a real professional
job. What I am showing here is a practical method, that works well.
Note that my method is 'time-consuming' only in that you
must do repeated applications (explained later herein), each of which only takes
a FEW minutes....but you must let the application cure overnight. Thus my
method requires a few minutes every day. MINUTES...not hours!
The INITIAL prep work labor will vary a lot, depending on the damage.
It is important to understand a few things first. BMW
fairings are NOT molded plastic, they are NOT fiberglass either. BMW
fairings are made from resins, that have a filler ingredient that I THINK is
primarily TALC. I recommend against a quick and dirty hasty
job with 5 minute epoxies. It is not necessary for me to get into the type
of plastic resins that BMW uses, and other technical minutiae, because it is NOT
pertinent here.
This is the my basic method for repair:
1. Remove any hardware that is in the repair area that would interfere
with a good repair job. CLEAN the damaged area with acetone.
2. Sand the damaged area on the OUTSIDE. Just how wide and long is
up to your repainting efforts. Some will want to only do touchup painting
with a fine brush, so their method will be to sand the crack into a V form, and
not sand much outside the crack V; others will do a bit wider for slightly
better adhesion. BOTH will work.
3. Sand the OUTSIDE until all the paint is removed from the crack, AND, at
least slightly outside the crack (at least 1/16"). Just how much
sanding and width will vary with the damage. In most instances, the paint
has cracked in a jagged pattern at the broken edge, and you want THAT sanded to
a nice edge. End up with the last sanding being done with 100 or 120 grit
sandpaper.
4. On the INSIDE of the fairing (typically painted BMW black) sand much
more vigorously and MUCH wider. You want a large sanded area.
I also recommend doingk the initial sanding with 50 grit and ending with 80
grit. Hard to give a rule of thumb for this, but perhaps at least an inch or
more in width. Get ALL black paint off the area you will be dealing with
by sanding.
5. You can, depending on what the crack looks like, sand a slight V on the
INSIDE.
NOTE that in some instances you may NOT want to sand a V,
or hardly any, on the OUTSIDE, but make the larger V on the inside.
This is done when you want MINIMAL exterior touch-up painting, such as with a
very tiny thin brush on the outside, with touchup lacquer.
6. I use 50 grit and 80 grit sandpaper for the most part, ending
with 100 grit, nothing finer than 120. I like the INSIDE of the fairing
done with 50 and 80.
7. CLEAN all surfaces with ACETONE. Do NOT use your wife's finger
nail polish remover acetone, as some contains oils.
8. If any parts need to be clamped or otherwise held in position, you
should do that as best you can. It is actually possible to use a
strong duct-tape on the outside or inside, while you repair the opposite
surface! I prefer to place the tape on the OUTside and repair the INSIDE
first, as the inside repair will be the much larger and stronger repair.
9. In some instances you may be installing a clip or threaded post, etc.,
into the material, then epoxying it in place. For any specific
instance, consider when you will do this, it is NOT always the first thing.
Sometimes it is the last thing before the touchup painting. Do NOT
get epoxy into threads. If you do, clean it out immediately as best
you can, and be prepared to tap the item to do finish cleaning, after the epoxy
fully hardens. YOU CAN epoxy threaded fasteners, etc., into the
fairing, quite successfully too. Many of the round-type threaded fasteners
that BMW casts into the fairings have rough outer surfaces, which bond well to
epoxy. I tend to plug the inward side of the insert, so epoxy does not get
pushed into it, as you push the fastener into the epoxied area. WAX will
do OK for this. You can also fill the tube fastener with Vaseline...be SURE the
outside is NOT contaminated!
10. BE SURE you are totally ready to do the final steps...you MUST
have clean bare sanded surfaces.
11. Use ONLY marine grade two-part EPOXY. It MUST BE EPOXY,
not any other type of material. Do not skimp, get the proper materials.
12. You can do the inside or outside first.
13. Large cracked areas MUST be backed-up by use of fiberglass cloth and
in some instances you will need a filler like fiberglass mesh or gauze or
matting. I do almost all my fairing repairs with just fiberglass
cloth/matt, it is easier to work with.
14. Cut the fiberglass cloth to roughly the size needed. I start
with a smaller piece, and use a stiff 'acid brush' to work the freshly mixed
epoxy into the fiberglass and work it into the V groove. Be
sure to use the brush properly, work the epoxy into and through the fiberglass
cloth, and brush out any air bubbles.
Let it dry and harden overnight. It is up to you as to the speed of the
hardening of the mixture (the hardener percentage determines the speed). I
have used 10 minute and 15 minute mixtures, and I still let them fully cure
overnight.
15. The next day, SAND the work you just did. Be thorough.
16. Clean with acetone.
17. You are now ready for the next cloth and epoxy application.
Build up the OUTSIDE to a bit higher than the original finish, so you can sand
to the exact level of the finish. You may be doing several applications
and overnight hardenings, until you get an outside that can be sanded down and
look good. Usually I find that if the V is on the outside, I use
LITTLE fiberglass cloth or matt.
18. The inside can be MUCH cruder, and MUCH larger patch sizes of the
fiberglass SHOULD BE used. This is where the major strength of the repair
is made. Remember that you must allow overnight hardening and fully
curing; remember to sand, remember to use acetone.
Built up the inside repair area to several layers thicker than you might think
you want. You need strength, and a wide area.
19. The final inside fairing cleanup can be rough sanding of sharp edges,
acetone cleaning, and then spray can black painting.
20. I wait a full week for a 100.00% cure of the epoxy on the outside,
then I prepare and paint with a very fine brush. If you do it carefully,
it can be hardly noticeable.
It is up to you whether or not to put a clear coating over your outside work.
Notes:
marine grade epoxy and hardener are typically sold in pints as the smallest
container. You are unlikely to be using very much of it. Keep the
cap on tightly and in a COOL PLACE when you are done with your work. DO
NOT leave the cap off during your work. Measure the amounts of each part
you need into one small container, and mix well, using swirls and figure eight
motions. I use almost any type of plastic teeny cup from grocery items that I
have first cleaned and dried. I collect them for this type of repair!
You can also purchase tiny mixing cups from your marine epoxy vendor.
You can use the left-over epoxy mixtures for any number of other jobs.
Epoxies are often mixed by either volume or weight. Be sure you get
instructions for a small amount of mixture, before you leave the store.
Acid brushes are available at almost any hardware store. These are thin rolled metal tubes, with a small brush on the end. CUT the brush down by maybe a third, so the brush is a bit stiffer. These are cheap, throwaway items. Harbor Freight sells them in packages of 100, cheaply. You likely will need a dozen or more anyway. These brushes are also useful for your spline lubrications jobs, etc.
Revisions:
01/28/2004: finally resurrected and uploaded as #44
08/13/2006: edit, revise, add information on plastics, etc.
02/19/2007: add luggage section, and expand a bit in 08/07.
11/29/2009: Clean up entire article some
07/20/2010: Some cleaning-up; minor clarifications, add
copyright notice and proper Google coding, etc.
05/09/2011: Slight updating and cleaning-up.
01/16/2012: Greatly expand fairing section.
© copyright, 2012, R. Fleischer