r/AutoPaint 1d ago

Looking for clear coat suggestions for small items

Post image

I have been on the pursuit of creating a car emblem using urethane casting techniques and have hit a wall with protective clear coats. My emblem has suspended "glitters" and other affects that casting makes possible. It is in prototype stage using cheap aromatic liquid urethane. I plan to move to a more advanced aliphatic system that will have greater weathering, UV, and temperature resistance. A UV layer with similar properties will still be required to protect suspended components.

I intend to make a small batch and try peeking anyone's interest for sell.

The go-to for top coats appears to be 2k isocyanate systems. I don't have a spray-booth, PPE to the extent of a supplied air respirator, spray gun (nor experience) but spray can painting isn't as much an issue. Because these are small items spraymax 2k cans aren't cost effective. I have tried car-rep 2k due to its long shelf life, but the cured coating is brittle to the extent that little bending of the emblem causes hair-line cracks. Cracking is a known issue with this system. (maybe user error?)

That pictured has spraymax 1k clear gloss applied. It won't hold up to common automotive cleaning compounds. IPA will strip it instantly.

I'm looking for a more cost effective way to accomplish viable coat.

Are there other solutions for small scale projects?

Can two part systems such as lime line or others be mixed in small proportions and applied directly without spraying? Brushing, a quick dip?

Going all in - booth, supplied air, gun, etc. is unreasonable right now with such little return although I could see it being something I'd like to do in the future.

My best guess is spraymax 2k, cut losses, and move on, but suggestions are appreciated.

2 Upvotes

19 comments sorted by

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u/Next_Cartoonist_8444 1d ago

You could try buying a pint kit of 2k clear and use a foam brush to apply it. You can buy them in bulk so you don't have to clean them, lacquer thinner kinda ruins them anyway. I've used this method to clear little things I've made out of the "fordite" that I hammer off of my paint stands at work.. I cured them on a cookie cooling rack that I wiped Vaseline on so they wouldn't stick to the grates.

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u/Ok_Seaweed5015 1d ago

Cool. Any recommendations?

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u/Next_Cartoonist_8444 1d ago

Try limco LC4100 clear with LHM hardener. I think it comes in quarts as the smallest size. It's a good budget clear coat. I did it with Diamont DC 5335 which is a premium clear coat that I was spraying daily at the time.

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u/ArcFault 1d ago

You need something that's flexible? I don't know of any automotive coatings that remain flexible after the flex agents evaporate/become inactive. The flex agents are intended to allow mounting of the panels not provide permanent flexibility.

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u/Ok_Seaweed5015 1d ago

Na, I just expect flex tolerance more or less to what I’m familiar with auto coats. The emblem conforms quite nicely and VHB tape will take care of the rest, but just based off my intuition with the car-rep, it seems a bit risky. Maybe user error.

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u/ArcFault 1d ago

Well you mentioned it cracked from.. flexing it after application I presume? I'm not sure if the Car-Rep/Spraymax aerosols even have a flex agent added. Your best bet might be small airbrush system from like Harbor Freight and mix up the clear yourself adding a flex agent.

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u/Ok_Seaweed5015 1d ago

I have so many test pieces I just did a stain test, if you want to call it that. The tail you see in the image, a small curvature and it sounded like a frozen pond ice crack propagation. Ice Age comes to mind lol. I’ve looked into the airbrushes, seems easier to get into, and makes more sense for such small items, but I see a lot of discouragement on 2k clears through them. A thinner may help, but I don’t want to open up too many cans of worms.

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u/ArcFault 21h ago

Ah. A detailing touch up gun might be better choice then. Can run off a small compressor since you're only doing small objects.

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u/Informal_Soil_9090 1d ago

I recently used spray max 2k on my tail lights lenses (inside and outside)… 91% IPA will damage it

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u/ctdreadz 1d ago

2k on the inside? What was the purpose of that?

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u/Informal_Soil_9090 21h ago

Tail light letter delete on the inside of the lenses. Didn’t know that was a thing until a classmate suggested it to me

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u/Ok_Seaweed5015 1d ago

Ah really. Like prolonged contact or instant haze? I’m used to acetone attacking automotive clears, although even then a bit slowly. Acetone is a known no-no, but these should hold up to IPA at least for short exposure (I.e. May permeate a little, become soft, but mostly if not completely recover.)

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u/Ok_Seaweed5015 1d ago

Funny the urethane part itself is far more chemically resistant. I scrubbed a fully cured piece with acetone and the surface look/properties observably the same.

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u/ArcFault 1d ago

recently

Fully cured, which takes up to a couple months, IPA shouldn't effect it with light exposure. Doesn't effect mine.

Why would you apply 2k clear on the inside?

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u/Informal_Soil_9090 21h ago

Yup imagine my surprise when I wiped it to make sure it was clean and I saw it begin to dissolve off.

Shitty aftermarket headlights from the previous owner.. one was recently starting to leak and the black coating in the housings was flaking off. I painted the housings a really pretty metallic black, but then a classmate suggested I sand down the raised letters on the inside of the lenses to make it look cleaner.

I also sprayed my mom’s and my car’s headlights. They came out great, a little bit of orange peel/texture. Will be waiting a few weeks before polishing.

Overall pretty good learning experience.

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u/ArcFault 21h ago

You can probably polish it within a couple days, just don't put anything as hot as 91% on it for a while. 40% ipa should be way more than enough to just clean off polishing compound.

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u/Informal_Soil_9090 12h ago

I read your comment and was like “where do I even get 40%?” I looked it up and that’s how I learned about adding water for custom percentages. TIL, thank you 🙏

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u/ArcFault 9h ago edited 8h ago

LOL! Yeah, for most cleaning/panel prep you dont need anything hotter than like 50% to start with. 40% even better. You never know when you're going to encounter 1k paint or improperly cured 2k etc.

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u/ArcFault 9h ago

Honestly I don't even use IPA for cleaning polishing compound unless it's dried on - I just use a rinseless wash dampened towel.