Clear Over Base ON TOP of Celly?

[SpitfireIV]

Sprayed one of the front lower valances as seen in the below image, it's the top one with the darker color...

Again the finish came out quite nice with the 1.3 HVLP turbine. What I did was, two coats direct gloss and two coats clear, wet on wet. I think there's nothing really to be gained by applying the clear on top so I'll stick to two/three coats of direct gloss for the rest of the car, but I thought it'd be worth a try to see the effect.

Apart from some dust nibs and very soft orange peel the finish came out good off the gun....

Then after a flat and polish this handsome fella was plain to see in the reflection ....

Now the color difference between old and new is causing me a bit of a conundrum! What I was hoping to do was paint what could be seen on the outside of the car, door shut spray job. The original color was mixed by eye to a sample of the original color (Triumph color valencia blue #66). The paint supplier didn't have the code on the system for this color so got a pretty good match to the sample. The new color mixed in 2k direct gloss was on the system as a Triumph/Rover color number 66 Valencia blue so we can assume this is pretty close to the original but you can see an obvious difference between the two. So, I think it's a case of doors off and a bit of extra spraying around the insides of the doors, understand of boot lid etc, areas that I was hoping I'd get away with with perhaps a very slight color variance but not enough to really notice.


Apart from that the bonnet is being prepped. Spot epoxy primed, filled, flatted, epoxy primed and filled again before having an overall epoxy priming and.....flatting again. It's a big chunk of the car with a lot of flats and curves, I'm really looking forward to getting this in color but want to get it done right .....

 

[SpitfireIV]

And then it was white!

Couple of coats of epoxy primer applied this evening to the bonnet. Cleaned it up no end! Leave this sit for a few days (mostly because I haven't got the time to work on it!) before guide coating, flatting and reapplying epoxy where required....

 

[SpitfireIV]

Wet sanded the bonnet back with 400 grit which highlighted a few high spots in the form of cut throughs....

Spent time flatting with a flexible long and curved block. The bonnet is a big (and curvy) chunk of the car, I want it looking right!

Once I was happy with the wet sand it was washed, dried, panel wiped and epoxied again!

Getting ever closer to color! I cannot wait, if I can wrangle a day or so off next week from my boss (I work for myself ) and the weather gods align I'll get it colored!!

 

[ajlelectronics]

Once I was happy with the wet sand it was washed, dried, panel wiped and epoxied again!

It is not recommended to use water at any stage of preparation, all sanding should be done dry.

 

[SpitfireIV]

It is not recommended to use water at any stage of preparation, all sanding should be done dry.

Oh, bugger.

Why so? The bonnet is GRP so no fear of rust or such like. It was well cleaned after, dried and and degreased before being recoated. It sanded a lot better when wet.

 

[steveo3002]

some primers can soak up the water and cause blisters later on , i wasnt aware it mattered with epoxy

 

[ajlelectronics]

some primers can soak up the water and cause blisters later on , i wasnt aware it mattered with epoxy

In theory it doesn't but where you break through it does and also it helps to get into the right mindset for all prep. works.

 

[keithski122]

I'm old school and always wet sand, never had any problem apart from when I used a car cover outdoors but then again the problem could have been caused by painting in an open barn with no water seperator on the compressor or might just have been one of those things that happens with a cheap paint job.

 

[SpitfireIV]

Ok, so the bonnet had a subsequent flat back which highlighted a couple of areas that needed slight attention, these have been sorted and spot primed before the whole bonnet was given another quick once over with epoxy.

I'm hoping I can now start prepping for color. The epoxy laid on pretty smoothly with I suppose a very very fine texture, not dry, but not glassy smooth either. How smooth exactly is required before applying direct gloss? Am I right in thinking that the smoother I can get the epoxy the better the gloss coat will be? I'll hit it with 400 to knock off the heavy end and then scotchpad 600(?) I can't get any 500 locally.

 

[steveo3002]

guide coat and sand until smooth /guide coat gone

 

[barracuda816]

The gloss will only be as good as the primer under it. If it’s only a light texture I would be tempted to just hit it with 600 dry.

 

[ajlelectronics]

Direct gloss you can often get away with 400 for light colours, otherwise 5 or 600 would be the answer. 800 for metallics.

 

[SpitfireIV]

Progress has been slow. Free time hard to come by....

The bonnet required a tad more work, upon flatting with P400 and guide coat in prep for final P600 flatting it highlighted a couple of high spots that have required spot priming HOPEFULLY for the final time.

In the meantime I got some parts sprayed today, these are parts from the front, two of which I had previously sprayed as per my earlier post but I had used a method of clear over the 2k gloss, wet on wet, I wasn't overly happy with this method so stuck with the direct gloss. Thus the panels were flatted back for respray.

Very happy with how these panels turned out straight from the gun. Turbine sprayer , siphon fed 1.3 nozzle. A bit of dust in the finish given my less than ideal spray booth but they're nothing that a rub of 1500/2000 won't sort. Very soft to almost non existent orange peel. I applied a dust coat initially and then followed this with three wet coats, approx 30 mins between and when the previous coat had a slight tack. No discernable runs or sags

 

[steveo3002]

looks very good , theres bodyshops that turn out worse

cleary it seems to be working for you but , i wouldnt really recommend a first dust coat myself , its only a chance to introduce peel

 

[ajlelectronics]

looks very good , theres bodyshops that turn out worse

cleary it seems to be working for you but , i wouldnt really recommend a first dust coat myself , its only a chance to introduce peel

It shouldn't be. The 'dust coat' is a very light, thin application which helps with adhesion. Peel comes from over application of paint.

 

[steveo3002]

light coat , not dry /dusty

 

[SpitfireIV]

So I flatted back and polished up the lower valance today which raised perhaps a minor issue that I think I know where the issue lies but you might give me clarity before I undertake more major element's of the car. The piece pictured here is on the bottom of the car at the front so not really visible.

Anyway, I hit it with a bit of 1500, then 2000 and then onto the compound and polish. Came up really nice...

On closer inspection however I noticed some darker patches, only visible at certain angles, like such....

And....

OK, the one above it difficult to make out as its quite jagged.

To me these look like cut throughs to the layer below, is this possible? If so what might have caused this? Did I perhaps leave too long of a gap between the second and last coat so they didn't merge into each other? But why the difference in tone? The paint was the same, mixed to the correct ratio's etc.

I'd like to understand where I went wrong before I commit to larger, more visible areas

 

[ajlelectronics]

It's called "grinning". Various possibilities but the answer is as you thought, the substrate. Was the primer all one colour or were there spot repairs? Also can be caused by stopper shrinkage etc.

 

[SpitfireIV]

It's called "grinning". Various possibilities but the answer is as you thought, the substrate. Was the primer all one colour or were there spot repairs? Also can be caused by stopper shrinkage etc.

Yes the primer was uniform, a very light grey 2k epoxy so I don't think it's the original colour coming through as I would have had to cut through primer to get to that. No stopper used on this panel so I'm guessing it's simply a cut through of the top layer as I may have left too long of a window to apply the last coat.

 

[ajlelectronics]

Yes the primer was uniform, a very light grey 2k epoxy so I don't think it's the original colour coming through as I would have had to cut through primer to get to that. No stopper used on this panel so I'm guessing it's simply a cut through of the top layer as I may have left too long of a window to apply the last coat.

It ma be an adhesion issue, difficult to be certain without seeing it in person. Some looks like the gun spitting and other areas look like grinning. If you refinish it, it would be interesting to know what you find as you go down.