Painting an i3's Roof

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If I can find someone to paint our roof, I will relay your cotton cord method so that the edge of the paint would be under the rubber seal. Maybe professional painters already know how to do this, but I certainly didn't. Thanks for posting this!

I wonder whether paint shops who paint Corvette fiberglass bodies would know how to paint the i3's CFRP roof correctly. Different fiber but maybe a similar clear top coat.
 
The traditional way that a rubber gasket or seal is pulled back to allow paint to continue under the demarcation of the rubber and the paint surface is to use cotton cord. A.125 or eighth inch cord is stuffed under the flexible rubber edge so as to hold the rubber up. Then mask. Then when done,a razor knife and care is slowly used to pull the cord out. Cars used to use rubber to seal glass, this way glass not removed but paint is sealed under the rubber. If u simply paint up to the rubber leaving an exposed edge, that will fail.
I'm not near the i3 now, but as I recall, the rubber-flap/seal geometry is such that if it's raised to clear the CFRP that it's intended to seal against, it comes perilously close to being in the plane that will be sanded during prep of the roof - so one might find it's been damaged/sculpted as a result. I like to get stuff amply clear of an area to be painted to avoid nasty surprises like that.

But the cord-stuffing method seems like it would work very well for many applications. Nothing turns me off about a 'restored' classic like 'ring around the gasket.' Even the most precise masking doesn't give clean results without using something like the trick you're describing.
 
Fiberglass is not carbon fiber. The body shop I used repairs some high end cars with carbon fiber parts. The owner (son of the original owner) has done all the painting there for 30 years.

I did not get all the details but:
- “Carbon fiber is it’s own animal”
- A sealing coat is needed, then a day to dry before painting. Do not touch the paint for a month (wash, wax, etc) to allow for the sealing coat to completely evaporate through the paint.
 
Fiberglass is not carbon fiber. The body shop I used repairs some high end cars with carbon fiber parts. The owner (son of the original owner) has done all the painting there for 30 years.
The fiber doesn't matter; the clear coat over the fiber does. The i3 roof might have a different clear coat than over the carbon fiber in the passenger cabin and that's on typical fiberglass. The visible CFRP door sills look different from the roof.
I did not get all the details but:
- “Carbon fiber is it’s own animal”
- A sealing coat is needed, then a day to dry before painting. Do not touch the paint for a month (wash, wax, etc) to allow for the sealing coat to completely evaporate through the paint.
You're lucky to find a local paint shop that knows what it's doing. I haven't been able to find a local paint shop that has any CFRP experience or that wants to learn how to paint CFRP correctly. That's why I'm considering branching out to shops with fiberglass painting experience which might not be ideal. I'll ask our BMW dealer whether BMW doesn't approve painting CFRP roofs which is the excuse that their certified body shops used to refuse to paint the roof of our i3. These shops might be blowing me off because they're too busy or want only larger jobs.
 
The fiber doesn't matter; the clear coat over the fiber does. The i3 roof might have a different clear coat than over the carbon fiber in the passenger cabin and that's on typical fiberglass. The visible CFRP door sills look different from the roof.

You're lucky to find a local paint shop that knows what it's doing. I haven't been able to find a local paint shop that has any CFRP experience or that wants to learn how to paint CFRP correctly. That's why I'm considering branching out to shops with fiberglass painting experience which might not be ideal. I'll ask our BMW dealer whether BMW doesn't approve painting CFRP roofs which is the excuse that their certified body shops used to refuse to paint the roof of our i3. These shops might be blowing me off because they're too busy or want only larger jobs.
Art, I'd try (if they still exist) the Corvette quonset-hut shop down in Kakaako, if they still exist - can't quite recall their name. But any auto paint shop should have experience painting/blending FRP body accessories like fender-flares, whale-tails. It's not exotic. Another angle would be to start with paint suppliers for automotive lines, eg Hi-Line, Tropical Auto, Sherwin-Williams (airport area is the automotive supply location). Tell them about your project and ask them what shops come to mind for that type of work.

Pretty sure they'd be amused to hear how there's all this concern over painting CFRP, FRP, etc.
 
Art, I'd try (if they still exist) the Corvette quonset-hut shop down in Kakaako, if they still exist - can't quite recall their name.
That would be Chuck's Corvette Clinic which I was considering when I thought about contacting body shops that paint fiberglass. I drove by their quonset hut recently and they still appear to be in business. However, their Website doesn't appear to have been updated recently. Their phone number is still working although without any voicemail.
Another angle would be to start with paint suppliers for automotive lines, eg Hi-Line, Tropical Auto, Sherwin-Williams (airport area is the automotive supply location). Tell them about your project and ask them what shops come to mind for that type of work.
Good suggestion! Thanks!

Hope your relocation to Hilo is going well and that Hurricane Hone isn't flooding your home.
 
That would be Chuck's Corvette Clinic which I was considering when I thought about contacting body shops that paint fiberglass. I drove by their quonset hut recently and they still appear to be in business. However, their Website doesn't appear to have been updated recently. Their phone number is still working although without any voicemail.

Good suggestion! Thanks!

Hope your relocation to Hilo is going well and that Hurricane Hone isn't flooding your home.
We had a quite spectacular adventure in our first (and only) attempt at making the Crossing to Costco in the i3. The big mistake was my agreeing to add a side-trip to Hapuna Beach, all without any supplementary charging other than REx...that kind of thing has probably been chronicled elsewhere here, though.

The formerly-subtle blister atop my roof has been tortured by alternating sun/rain in recent months such that it's now looking like an elephant's skin, so I'm going to have to do something for it. Good news is I've got the garage there. Bad news is pretty much no tools - a big air compressor being the most obvious missing element. I'll figure something out. Might have to actually (gasp...gulp) find a shop to do it.
 
We had a quite spectacular adventure in our first (and only) attempt at making the Crossing to Costco in the i3. The big mistake was my agreeing to add a side-trip to Hapuna Beach, all without any supplementary charging other than REx...that kind of thing has probably been chronicled elsewhere here, though.
The round-trip journey between Hilo and Kailua-Kona is long enough with enough gain in elevation to challenge even a 120 Ah i3 BEV without charging en route.
The formerly-subtle blister atop my roof has been tortured by alternating sun/rain in recent months such that it's now looking like an elephant's skin, so I'm going to have to do something for it. Good news is I've got the garage there. Bad news is pretty much no tools - a big air compressor being the most obvious missing element. I'll figure something out. Might have to actually (gasp...gulp) find a shop to do it.
When it's degraded badly enough, the clear coat could be peeled off the underlying carbon fiber cloth without many tools. The challenge is then what to cover the CF with to protect it. I've seen a couple of i3's with black painted CF roofs. Paint doesn't seem to provide much protection for the CF cloth and results in a rough finish. A surfboard repairer would have the right stuff for a good clear coat, I would think.
 
Art, I'd try (if they still exist) the Corvette quonset-hut shop down in Kakaako, if they still exist - can't quite recall their name.
I stopped by Chuck's Corvette Clinic yesterday after finally getting my Hawaiʻi safety inspection at BMW of Honolulu after importing our i3 into Hawaiʻi from California in early July. Driving our i3 on Hawaiʻi's roads is now legal! Woohoo!

Chuck is probably about my age. He's been working on Corvettes and custom cars of all kinds in his WWII quonset hut for ~45 years. We bonded over stories of our past Corvette ownerships. However, despite his shop's name, he now drives a custom Ford Ranchero hotrod with a 428 Cobra-jet engine.

Chuck climbed up on the door sill of our i3 to get a better look at its roof. With his long Corvette painting experience (nice, professional paint booth in his shop), he saw no problem painting it Galvanic Gold Metallic (paint code C4Y to him). However, after confirming with me that our i3 is an EV, Chuck's local wife and business partner informed him that they don't work on EV's! Neither Chuck nor I could understand why he painting the roof of our EV would be any different from painting the roof of a BMW M car with a CFRP roof. He told me that he would talk to his wife after I left and would call me later. After less than 10 minutes, I received a call informing me of the cost and telling me that I would be called during the second week of September to schedule the paint job. I'm cautiously optimistic that this will actually happen and that the result will be nice. This really shouldn't have been this difficult. Photos will be posted of the successful painting.
 
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I stopped by Chuck's Corvette Clinic yesterday after finally getting my Hawaiʻi safety inspection at BMW of Honolulu after importing our i3 into Hawaiʻi from California in early July. Driving our i3 on Hawaiʻi's roads is now legal! Woohoo!

Chuck is probably about my age. He's been working on Corvettes and custom cars of all kinds in his WWII quonset hut for ~45 years. We bonded over stories of our past Corvette ownerships. However, despite his shop's name, he now drives a custom Ford Ranchero hotrod with a 428 Cobra-jet engine.

Chuck climbed up on the door sill of our i3 to get a better look at its roof. With his long Corvette painting experience (nice, professional paint booth in his shop), he saw no problem painting it Galvanic Gold Metallic (paint code C4Y to him). However, after confirming with me that our i3 is an EV, Chuck's local wife and business partner informed him that they don't work on EV's! Neither Chuck not I could understand why he painting the roof of our EV would be any different from painting the roof of a BMW M car with a CFRP roof. He told me that he would talk to his wife after I left and would call me later. After less than 10 minutes, I received a call informing me of the cost and telling me that I would be called during the second week of September to schedule the paint job. I'm cautiously optimistic that this will actually happen and that the result will be nice. This really shouldn't have been this difficult. Photos will be posted of the successful painting.
I LOLd at this great story!
 
I stopped by Chuck's Corvette Clinic yesterday after finally getting my Hawaiʻi safety inspection at BMW of Honolulu after importing our i3 into Hawaiʻi from California in early July. Driving our i3 on Hawaiʻi's roads is now legal! Woohoo!

Chuck is probably about my age. He's been working on Corvettes and custom cars of all kinds in his WWII quonset hut for ~45 years. We bonded over stories of our past Corvette ownerships. However, despite his shop's name, he now drives a custom Ford Ranchero hotrod with a 428 Cobra-jet engine.

Chuck climbed up on the door sill of our i3 to get a better look at its roof. With his long Corvette painting experience (nice, professional paint booth in his shop), he saw no problem painting it Galvanic Gold Metallic (paint code C4Y to him). However, after confirming with me that our i3 is an EV, Chuck's local wife and business partner informed him that they don't work on EV's! Neither Chuck nor I could understand why he painting the roof of our EV would be any different from painting the roof of a BMW M car with a CFRP roof. He told me that he would talk to his wife after I left and would call me later. After less than 10 minutes, I received a call informing me of the cost and telling me that I would be called during the second week of September to schedule the paint job. I'm cautiously optimistic that this will actually happen and that the result will be nice. This really shouldn't have been this difficult. Photos will be posted of the successful painting.
One can infer all KINDS of things about 'the wife' from this...eg that she's a hard-core bureaucrat, who says that their rules of incorporation prohibit any and all work on EVs?

In my shameful other driving existence - a ratty but vital 1997 Dodge diesel dually (with a DUMP bed, is the point there) - I needed a shop to change the pinion oil seal, something generic to all differential-equipped cars. I called at least eight shops in town. A frequent response was "oh, no, sorry, we don't work on DIESELS." It became a DIY project as a result, involving copious swearing.
 

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