With the filling and sanding complete, three minor things (I hoped) remained to address the rusty cowls: Finish up minor filler work on some remaining blemishes, clean the cowls down thoroughly and prime them.

Remember, it’s not my intent to get a thorough primer finish at this point ready for a topcoat. It’s more to cover and protect the work to date until such time as I’m ready to paint the entire scoot. Dent filling and rust removal is something I need to do anyway so I consider this groundwork. That said I did use this opportunity as a test run to aim for an even primer coat.

I learned some important lessons very quickly:

First. Automotive filler requires two parts to harden. The paste itself and a small “dab” of hardener thoroughly mixed in. This time I was a little over generous with the hardener and the filler only remained workable for less than three minutes. It became a rush to add it to the cowls before it hardened. If in doubt, use less of the smaller tube than you think.

Hanging the cowls after sanding but before cleaning.

Second. Run; don’t walk away from Bright Beauty Sandable Primer. It was handed to me as the default primer at Danken Auto Parts and it is absolutely useless. The majority of the primer dripped down the can rather than spray from the nozzle. The primer that did spray sprayed erratically and inconsistently. Because of all the wasted primer, one can didn’t even cover a cowl. Before I proceed I’m going to see what else is out there in a primer rattle can. Roughly speaking I put on three coats, with a 15 minute wait between coats. This is better documented elsewhere, but the trick is to keep a consistent distant from your target and begin and end spraying away from the panel.

After three "coats" of Bright Beauty Primer, the battery-side cowl still needs more.

Third. Just because you’ve finished priming doesn’t mean you’ve finished prepping for a color topcoat. The consistent gray of the primer allowed me to see areas that still needed either a touch more filler, or more careful sanding down to a smoother surface. Fortunately the primer is of course still sand-able. Clearly this is the stage to get everything right before a color topcoat. I can see this taking at least two, probably three stages of priming and sanding to get to that flawless substrate needed for a spotless paint job.

The procedure? After filling and dry and wet-sanding down to a smooth finish, the final stage before priming is a thorough cleaning. Again using JPM’s guide I thoroughly washed the cowls down with soapy water and used Comet powder cleaner with the green side of a dish sponge to do a final abrasive pass over the panels.

Next, a rinse with water, and thorough drying with paper towels before a tack cloth wipe over to get the last of any dust and other particles off. I was much more vigilant with the outside of the cowls than those parts that face into the engine and battery. I rigged up two coat hangers from the basement ceiling to hang the cowls on to prime, and found it easier to hang them before towel drying and tacking to keep them as dust free as possible. I used the basement hatch to provide indirect ventilation.

After primer. Before primer.

Next? Well clearly I need to try a different primer. A brand name I’ve heard of for a start. With that in hand, I hope to finish an even coat of primer on both cowls. Identify and correct any missed sanding or filling and then spot prime again, repeating as necessary until I’ve gotten a satisfactory primed finish. The cowls will then be reassembled and put back on the bike.

Work accomplished:

• Finished filler on both cowls.
• Cleaned both cowls thoroughly.
• Mostly primed the battery-side cowl.
• Started primer on the engine-side cowl.

Materials used:

• Filler
• Filler spreader
• Soap, water and Comet powder cleaner
• Paper towels
• Tack cloth
• Bright Beauty Sandable primer (caveat emptor)

Lessons learned:

• With the filler, keep the ratio of paste to hardener correct.
• Spend more time shaking spray primer than spraying it.
• The first primer coat doesn’t mean you’re done with corrective work.

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