Bush mechanic - a little Gravel Rash removed

[dave]

Hi Pterodactyl, beautiful job, congratulations. I have some scratches I would like to repair on my VFR800 engine case; can you please answer a few questions? First, what does "etch prime" mean? Is this some kind of a special primer? second, what brand of paint did you use? Thank you.

Hi Dave, thanks. Without seeing the case it's hard to give advice. As a rule it is best to paint the complete panel or part. This reduces the effect of any colour mismatch.

1. For an aluminium engine case (as in my pics above) first remove the scratches. If necessary start with a coarse grade wet and dry paper, or a file/emery wheel if it's really deep. Just be careful not to go so thin on the case that it's structurally degraded. Once you are back to shape, use decreasing grades of w/d paper down to about 400 grit, or even 1200 if you like, to get it as smooth as you can. Wash down with turps.

2. Mask off the area to be painted. Mask along joining seams or the edge of the piece if possible. Mask a big area as over-spray can travel huge distances. Throw covers over the rest of the bike. As you can see by my pics I just used painters masking tape and newspaper. Mine's as rough as guts but you get the idea.

3. What kind of paint? I used White Knight paints. It's Australian but I am sure you can source American products that are as good or better. On the side cover of the CB I used engine enamel, not hi temp enamel, as it doesn't get that hot. Colour aluminium. Have a look around the web site:

[url=http://www.whiteknightpaints.com.au/specialty-paints/high-temperature/engine-enamel]White Knight engine enamel

4. Before you go any further remember; PATIENCE IS THE KEY. Don't be in a hurry. It's counter productive.

5. Spraying with pressure pack paints is not difficult and for small areas is easier and cheaper than a spray gun and two pack paints etc. Read the directions on the can. If you have never painted before have a practice on another piece of material just to get used to the distance and rate of spray. First a misting spray then after a few seconds, nice parallel, slightly overlapping runs at the right distance, about 20cms from the piece. Keep the rate so that you don't get runs in the paint. If the pant runs then let it dry then rub it back.

6. Etch Primer is a paint that is designed to physically bond itself to the substrate to which it is applied. This is achieved by combining an acid with the paint so that the acid microscopically etches the surface of the substrate, thus forming a physical and chemical bond between the two. In most cases a colour will be added to the Etch Primer so that it can be seen. If you put enamel direct to metal it won't stick for long. With etch it sticks like the proverbial poop to a blanket.

7. I put one coat of etch then four coats of enamel (this will depend on the thickness and how your coats look). You may get some discolouration on the first and second coat of enamel but keep going, all will be well.

8. I used a gloss clear coat (two coats) to finish. I didn't bother with high temp, but high temp semi-gloss is available. Maybe even gloss, depending on the brand you choose. Don't be in a hurry to put the clear coat on. Give it three or four days, or longer, for the enamel to cure.

9. Let the whole shebang cure properly before polishing with something like "Mr Sheen"

10. Have a beer while looking at a thing of beauty.

Good luck and cheers.

Hi Dave, thanks. Without seeing the case it's hard to give advice. As a rule it is best to paint the complete panel or part. This reduces the effect of any colour mismatch.

1. For an aluminium engine case (as in my pics above) first remove the scratches. If necessary start with a coarse grade wet and dry paper, or a file/emery wheel if it's really deep. Just be careful not to go so thin on the case that it's structurally degraded. Once you are back to shape, use decreasing grades of w/d paper down to about 400 grit, or even 1200 if you like, to get it as smooth as you can. Wash down with turps.

2. Mask off the area to be painted. Mask along joining seams or the edge of the piece if possible. Mask a big area as over-spray can travel huge distances. Throw covers over the rest of the bike. As you can see by my pics I just used painters masking tape and newspaper. Mine's as rough as guts but you get the idea.

3. What kind of paint? I used White Knight paints. It's Australian but I am sure you can source American products that are as good or better. On the side cover of the CB I used engine enamel, not hi temp enamel, as it doesn't get that hot. Colour aluminium. Have a look around the web site:

[url=http://www.whiteknightpaints.com.au/specialty-paints/high-temperature/engine-enamel]White Knight engine enamel

4. Before you go any further remember; PATIENCE IS THE KEY. Don't be in a hurry. It's counter productive.

5. Spraying with pressure pack paints is not difficult and for small areas is easier and cheaper than a spray gun and two pack paints etc. Read the directions on the can. If you have never painted before have a practice on another piece of material just to get used to the distance and rate of spray. First a misting spray then after a few seconds, nice parallel, slightly overlapping runs at the right distance, about 20cms from the piece. Keep the rate so that you don't get runs in the paint. If the pant runs then let it dry then rub it back.

6. Etch Primer is a paint that is designed to physically bond itself to the substrate to which it is applied. This is achieved by combining an acid with the paint so that the acid microscopically etches the surface of the substrate, thus forming a physical and chemical bond between the two. In most cases a colour will be added to the Etch Primer so that it can be seen. If you put enamel direct to metal it won't stick for long. With etch it sticks like the proverbial poop to a blanket.

7. I put one coat of etch then four coats of enamel (this will depend on the thickness and how your coats look). You may get some discolouration on the first and second coat of enamel but keep going, all will be well.

8. I used a gloss clear coat (two coats) to finish. I didn't bother with high temp, but high temp semi-gloss is available. Maybe even gloss, depending on the brand you choose. Don't be in a hurry to put the clear coat on. Give it three or four days, or longer, for the enamel to cure.

9. Let the whole shebang cure properly before polishing with something like "Mr Sheen"

10. Have a beer while looking at a thing of beauty.

Good luck and cheers. Ho Pterodactyl - thank you very much. I'll google "etch primers" and see what I find.