Guide to Painting a motorcycle panel

[polecat]

So you want to paint your bike ? here is how to paint on a budget and without specialist equipment.

Stage 1 :Checking your panel

Assuming you are painting a plastic (ABS) panel first inspect the panel for any damage, if you discover a crack in it do not panic as you can easily repair it using the Plastic welding technique used in many body shops.

Dig out your old soldering iron and either find a piece of similar ABS from a broken panel or you can buy ABS sticks from vehicle automotive suppliers.

If you are using a broken panel as “welding rods” Then cut a strip about twice as wide as the thickness of the and about 5-7cm long.

Heat up your soldering iron then holding the crack together press the tip or the iron into the ABS about half way in across the crack forming a Stitch then continue to stitch the crack along its entire length so it looks something like Frankenstein’s neck ?(if you still don’t know what a stitch looks like ask your nan)

Once “stitched” turn the panel over and where the crack was cut a slot into the crack about half the depth of the panel( slot will be about 3mm wide) and only do this for one quarter the length of the crack (the stiches will hold on the other end )

Now heat your “rod” with the soldering iron until it starts to melt and then feed it into the slot, you can work the iron pushing the melting rod into the slot but careful not to push it through the other side (its actually quiet tough stuff)

Let the panel cool for a minute then cut a slot into the furthest quarter of the crack and once again work your melting rod into the slot then repeat the process until the whole crack is welded.

Once you have completed the run across that side of the crack turn it over and do the same on the reverse of the panel.

This process Welds both sides of the crack together and can be stronger than the original.

Once cooled you can instantly rasp or sand off the excess ABS until flat then you are ready for painting .

Get hold of an old panel and practice before doing this on your Expensive fairings but after a few goes you will be amazed how easy this is !

"Cut and shut"....If you become really comfortable you can actually weld two broken panels to make one whole one (providing they have opposing damage of course)

Think also about broken lugs, cutting lugs from broken panels and welding them on or even making new ones from ABS offcuts……With the price of plastic panels it can be well worth the effort.

[polecat]

Stage 2 : Metal parts inspection

Metal parts inspection

For Metal panels such as metal mudguards and more relevant Fuel tanks you need to check for dings, dents and rust.

Fuel tanks can get quiet rusty underneath so first decision you will have to make with metals is either strip down to bare metal or paint over the original scheme.

Back to basics

Remove tank, empty fuel from tank then remove filler cap assembly, fuel tap, and fuel gauge assembly (if not comfortable doing this then you can mask it in a small polythene bag and masking tape)

Protect the entrances to the tank with “bungs” you can make from cloth or newspaper and masking tape ect.

Beware of fuel vapours that may remain in the tank and take precautions !!

Use a good quality paint remover and paste it onto the tank with a 1”brush then place kitchen paper over the paint remover, soaking it (this prevents the paint remover drying to quickly and becoming ineffective)

Leave a good couple of hours then scrape the soggy paper mess from the tank and repeat if nessasary.

Once the tank is more metal than mess clean it off with a damp rag (use gloves cos it burns)

You can now run a 120 grit wet and dry over the tank in a back and forth motion to remove any excess paint and shine up that metal, taking care to ensure you get the paint off underneath as well.

If you have rust on your tank beyond light surface then coat the whole tank in phosphoric acid and leave overnight (placed in a tray to avoid acid on your carpet)

When your tank is shiney silver and you have washed off the acid with a damp cloth feel all over your tank with your fingertips looking (feeling) for any bumps or dents and if none and you are not ready to paint then give the tank a coat of WD40 or ACF50 on a rag as it start to form rust in a matter of minutes!

If you find a dent

What goes in must come out, so if you have a dent the metal will have come out at some point as the metal went in, usualy this is found on the outer edge of the dent (known as a high spot) Do not try to fill the dent without removing this.

Using a flat hammer head or flat wide file slap the outer ridge of the dent gently and repeatedly, feeling often with your fingers until the high spots decrease (do not just whack it)

Once satisfied that the dent only goes inwards then sand the dent area with an 80 grit wet and dry to score the inside of the bowl of the dent and the fresh sand marks will highlight the shape of the dent area.

Use a cloth and wipe the dent with degreaser and then mix some fine automotive filler and using a plastic card spread it over the dent area keeping the shape of the tank not the dent.

Spread the filler a good few inches larger than the dent as this will help with profiling when it sets.

Leave to set overnight and then using a sanding block and wet and dry (without water) start to sand along the planes of the tank without focusing on the dent.

The size of grit at this point will determine how much you take off so I would start with 80 grit and as the filler reduces switch to 120 grit

As you reduce the filler area it will leave normal metal tank below until the dent area becomes flush with the contours of the tank (Do not rush this process)

Keep feeling with your fingertips to make sure you are not too proud or starting to recess into the dent and you will be able to tell when you are nearly flush again (at this point I would go to 240 grit)

Once you are satisfied with the shape you can give the dent area a quick blast of primer to use as a guide to how it will look under paint and if it needs further sanding….. repeat as required and if you sanded to far then you can reapply a little filler.

Edited November 8, 2011 by polecat

[polecat]

Stage 3 : Make a spray bay

Before any painting you need to make yourself a Spray area which could be a shed or outhouse or even a homemade tent in the garden.

There is nothing worse than doing a lovely paint job to have a swarm of flies land in the wet paint.

Some ideas I have used are a large cardboard box with wire hangers inside, line the inside of your shed in plastic dust sheeting (about £3 from a DIY shop)

If you are really keen Make your own extractor with an old fan and some cardboard boxes for ducting ?

If you have Nowhere to spray then you can even make a cheap polythene tent from 2”x1” and dust sheets.

Once you have your area the best thing to Spray on is a sturdy table or workmate with a turntable on it to turn your panel as you spray (in case you don’t have all round access to the spray area )

The main thing is you have confidence the item can be sprayed all the way around and it will not fall off half way through, into a floor full of feathers.

You will need Good lighting and temperature no less than 14 degrees c

If it is raining then forget it and get on with something else !!

Humidity is worse than cold when painting so wait until you have a couple of days without rain for best results

Ready for Paint

Once Satisfied that your area is ready and the panel is all in order you need to give it a degrease all over, I find White spirit quiet good for this purpose.

Spraying

Give the panel a sanding all over with “Dry” wet and Dry paper around 240 grit

Keep the Sanding back and forth (not circles) before degrease.

Place the panel on your Sturdy table or workbench inside your “booth”

Before painting the panel with paint, run through in your mind how you are going to spray the panel in order to cover all of it, get your plan firmly in your head before squirting paint !

Shake can well !!

If the panel is metal then I would use a Zinc primer first and following my rehearsal pattern start spraying the panel by depressing the button on the can from right to left when I get to the far end release button now left to right pressing button following the line of shine from my first sweep and overlapping slightly so there is no Dry area between the two passes then down a bit press button and sweep back right to left ect (shake can when you get a chance during the coat)

I cannot emphasise enough the importance of planning, especially if you are doing something complicated like a tank.

Leave the paint to dry about 30mins to 1 hour depending on the temperature.

(Follow the coating times on the tin as they vary quite a bit from different manufacturers)

Once the first coat is dry Spray the second coat but this time turn the panel 180 degrees in case you had a “blind spot” on the first coat.

I use 3 undercoats zinc (for metals) red oxide, white ,grey reason being once the panel has become red I then spray white then finally grey, (If your base requires white undercoat then just change the order) this helps you see you are getting maximum coverage and not missing any facets.

I do not generally rub down between undercoats but if you made a mistake or got a Run, then Rub down a little with a wet and dry as required.

Once you have done your third coat and it has dried check it for any blemishes or sags, if you are happy with the way it looks run your fingers over it and see how it feels.

If you are still happy with the finish then take some 1200 – 1500 grit and lightly Dry rub the panel to remove any overspray that may have settled and leave to dry overnight.

Your panel is now ready for top coats

Edited November 11, 2011 by polecat

[polecat]

Stage 4 : Choosing a top coat

Two pack is far too dangerous in my view to be Spraying at home in a shed so will discount this as a choice.

Cellulose is now becoming prohibited because of the health implications for home use so is rare to find in spray cans now.

So what does that leave?

The favourite now appears to be either acrylic base and laquer or enamel

Enamel is was always oil based and acrylic water based

Its horses for courses but doing some research I have found that most home spray cans seem to be acrylic and nearly all the undercoat and primers also

You can paint oil onto acrylic but not the other way around.

So if you like most people, choose the easy option of acrylic then your choice does not end there!

Do you want a solid colour or do you want metallic or pearlescent?

If you choose a solid colour you may still require a lacquer coat as most car manufacturers do nowadays, so you may as well do a metallic

Go into Halfrauds or somewhere and have a look at the range from HOLTS car paints, you will be surprised at the array !

Once you choose your colour you will then need a compatible lacquer and if you are painting a fuel tank then some fuel resistant lacquer for final coat (around £6.99 from Halfords)

On top of all this you need 1200 grit wet and dry to sand your lacquer between coats, some rubbing compound and cloths and some good quality wax .

If you Mess up a bit during coating you can cut out a lot of the problem s using rubbing compound but if you have serious Orange peel effect, then there is also something called “leveller” which will make the paint fluid again and level it out (like a kind of solvent) but I would personally Rub down and recoat.

Edited November 12, 2011 by polecat

[polecat]

Stage 5 : Painting top coats Edited November 12, 2011 by polecat

[polecat]

Stage 6 : What can go wrong and how to put it right