Runs in paint on your engine.

[stevo as b4]

So I foolishly painted my new cylinder last week on that warm evening we had just as it was getting dark. I did 4-5coats of gloss black engine paint (should have been satin finish though) and I've got a couple of light runs on each side.
Its not noticeable from 3-4m away, only up close.

Should I rub down and re-paint the cylinder to try and get it flawless or just fit it and get on with riding my bike? Would anyone live with engine paint that wasn't a perfect job especially if the engine is on view? Opinions needed. Im having a step away from the bike and put the tools down moment, as I've applied one sticker just a fraction out of line, and I can't face going back in the shed since.

[Skudd]

Rub it down and start again. You know it's there and it will bug you for ever.
____________________
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[thx1138]

either that, or it's step 1 on your rat bike journey

[Riejufixing]

What bike and engine?

[Shaft]

Sounds like you need to brush up (ha ha, see what I did there ) on your painting technique.

Not enough flash time between coats and either too many coats, or too close with the paint nozzle.

Assuming you did it with rattle cans, leave a couple of weeks to harden fully, then gently rub back the runs - you might be lucky and flat them out, without the need to totally repaint.

A light dust coat will get the satin effect you were expecting.
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[thx1138]

[Ste]

pics or gtfo

[stevo as b4]

It admittedly was a case of rushing with poor preparation. That hot day last week seemed like ideal painting weather, and I had an hour or so of daylight left when I got in from work.

Regarding the satin, I meant that the original engine finish was a satin paint, but I did the cases in high temperature gloss. I wondered if it would look as good on the cylinder and head, but being rougher castings I think it's a mistake. Gloss shows up all the surface imperfections and so needs many more coats to get a decent finish I think.

I didn't leave enough flash time between coats I think, hence the runs forming. Its decent paint however and it has dried hard looks like black gloss powder coat except the runs.

I'll try just flatting the actual bits affected at the weekend, and then spraying a couple of light coats over the top with longer to dry between coats.

I think limited time and lots of wet/unsuitable weather for painting was the reason I rushed at it last week thinking it was the best chance I'd get. I can only paint stuff outside as I have no area indoors suitable for making into a makeshift paint booth, so it has to be a dry day without much wind.

Definitely want it to look good as I've just ordered new stainless steel Base nuts and head bolts to set it off. The problem with polished stainless steel fasteners I'm finding though is everytime you replace a manky bolt with shiny stainless, it just makes something else on the bike look shit.

All my fork yoke clamp bolts are plated OEM fasteners that are looking a bit corroded and I'm dreading trying to find the correct grade shiny bolts to replace them.

[Sister Sledge]

If you're struggling with manky nuts (and bolts) have you considered plating them yourself. There are some plating how to threads (bad joke!) here somewhere.

[u33db]

Google "gateros plating" for plating videos, they also supply the chemicals and plating equipment cheap too.

[stinkwheel]

You can't see it from the riding position.
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[Riejufixing]

[Shaft]

[Bikeless]

Your obviously not happy with it because your posting it, go do it again better, you'll be more satisfied in the long run,

[stevo as b4]

Cheers for the sense.
Yeah Its all on me, just piss poor preparation and painting in a rush in low ambient light caused a fuck up. Its a KMX as you say water-cooled cylinder with lots of nooks and crannies.

It was highcoat gloss black high temperature enamel I used, I like the paint, and the fact that it's tough and not damaged by oil or petrol.

As Shaft said, I need to rub back the high spots and runs and spray a couple of coats back on carefully. Im sure it'll come out fine, though I'd like to have done it the original satin black or silver if I started again, it would have been easier and a good contrast to the gloss casings.

Regards the corroded fasteners, I'm working around the bike changing a few at a time for stainless, but I see the negatives or the looking down on a bike that's covered in non original after market fasteners, especially as im using button and socket cap screws where possible. The fork pinch bolts will come out in the spring when I change to a refurbished set of 200 forks. That's something I'll look forward to as it's the final bit of spend this bike will see and I'm done then.

Regards these home plating kits, how good are they? Can you only do zinc or nickel plate finishes, and what's the most durable? All the plated bits on this bike have suffered since being done less than 4years ago. Is that green passivated finish a better durable option?

[Shaft]

[stevo as b4]

Well I sort of half followed your advice today, and stuck the cylinder in the oven for an hour at around 80degrees. I didn't have any paper higher than 400grit so I used a wet/dry scotchbrite pad instead.

The paint in the area of the runs came off quickly and down to the metal before I'd even really rubbed it.

After washing the cylinder and popping it back in the oven to dry, while my spray tin was sat on a hot radiator, I re-masked all the flanges, and gave it five more coats of enamel with 20-25min drying intervals.

After that I stuck it back in the oven for 25min to cure.

Its a semi success, in that I can't really see any runs, though the surface isn't perfectly even due to the varying levels of smooth and rough surfaces on the cylinder casting. But it's black and it's shiny and that'll do for me.

Ive packaged my cylinder head up after measuring the squish clearance, as it needs skimming now to get the clearance I'm looking for. I've got two heads to send off as im not sure the solder method of measuring squish is that perfect? Im going to get one skimmed more than the other, and then use my preferred blue tack blobs to do a final squish clearance check before deciding which head will go back on the engine. Of course this will need painting too so I've got all this fun to come again!

[Riejufixing]

[stevo as b4]

Thought that'd be obvious? I don't have a lathe or mill and though I know someone with a nice model making lathe it's not got a big enough swing for my head to fit.

I've got a couple of car engine reconditioning and competition/race engine building places not far from me, so I'm sure they'll be able to sort out a simple head skim for me.

[Riejufixing]

[stevo as b4]

Sorry pal but I do need an accurate way to machine an exact amount off my head face without any errors, as im trying to get clearances to within +/-0.1mm of a set value, and I don't want to affect the combustion chamber shape or profile.

You I assume are talking about rubbing a head on a piece of plate glass or wet/dry to clean up a mating face while taking off as little material as possible. That's not what I'm after.

I feel more confident with painting the head now with the same method as I used on the cylinder. Shaft is right that this engine enamel is different in the way it goes on and coverage to ordinary aerosol spray paint, I just needed some practice to get it to go on well and not too thickly.