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Old 07-14-2016, 10:29 AM
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Water bumps in clear coat

With the help of you guys I stripped my trans am to metal and painted.
I used lots of Spi epoxy to block sand and then DuPont (4 coats I think) and Spi clear ( three coats I think)
I guess I got confused with when to wet sand the orange Peel with not waxing for a few months. So the car sat for maybe two years collecting dust while I built the engine. I knew at the time of painting that a big water droplet came out of the gun and landed on the roof. I believe it was during the second or third coat of clear. It didn't bother me as the screaming chicken decal would cover it up.

Now that I am ready to clean and wax and maybe wetsand I am noticing lots of other very tiny bumps. You can catch your nail on them. They are maybe a foot apart on most of the car. Mostly side panels as we started the coat on roof then hood then sides.
I am pretty sure it is tiny water particles. I used two wall mount Chinese filters and never had this issue with the primer but it was only a couple coats at a time. I guess the four coats of base and three clear without draining the filter between overcame what the filters could handle.

So now I would love to hear your opinion if this is going to cause a long term problem with the paint, sanding down to base and re spraying is not an option as the paint booth I built is long removed.
The nubs really don't bother me that much as it was my first paint job and I am really proud of it regardless. It is also a driver that will get a few rock chips ect.

I am trying to decide if I should wetsand the clear and risk opening up these little air bubbles and having wax fill them making them look worse like white dots, or should I just do a fine polish and wax?

I have a Mikita rotary and maguires solo and #4

Last night on the bottom rear quarter I took a razor and scraped across the top and this is what I got





I gave a 30 sec or so wet sand with 2000 grit








Then a bit more




Then hit it with a medium foam pad and maguires solo



What are your thoughts?
Am I going to screw things up worse or should I keep going?

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Old 07-14-2016, 07:40 PM
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Before sanding those, you could fill them with clear on a small art or touch-up brush. Several applications with plenty of dry time between and after.... then carefully sand off the clearcoat dots until flush. Then try again with the sanding and buffing process.
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Old 07-14-2016, 07:52 PM
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That's a good idea, so treat it similar to a rock chip.
I have a small bottle of paintscratch.com clear. If it works do you think it makes a difference if I use this or should I mix up a bit of leftover Spi clear and use a toothpick.
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Old 07-14-2016, 07:59 PM
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If you have left over clear (but with fresh catalyst) thats best. If you use lacquer clear it may just melt out of the hole when you buff. It would probably look OK, you could try it and see. But yeah, pretty much treat as a rock chip but luckily the color coat is still there. Filling the holes with clear works better like the next day lol. You've really got nothing to lose, so give it a shot. Just don't thin out your clear too much when you sand off the bumps.
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Old 07-16-2016, 10:52 AM
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I decided to wet sand the whole car and now it appears there are only a few that need filling, the laquer seems to level it fine but those few holes appear or at least I will assume are deep maybe to the base. I don't want to risk going through the clear just to get a couple spots out so I just left them level.
The other 30 or so nibs appear to be trash and have the same circular look once we sanded but are coming out just past the orange Peel level.

Maybe I should start another post but while I'm here maybe I can go over my procedure for your criticism.

I have a
-Chicago pneumatic air sander with 2.5mm throw
-Cheap Titan vaper rotary with 7.5" majors pads (they look like rebranded lake country pads)
Maguires #4 I was using on the glass
Solo #86 compound

Only a little experience with the tools
4 coats base 3 med/heavy coats Spi UV clear
Started with 2000 grit 3M hand sanding and it would take down the orange Peel after a while then tried the rotary with med and heavy pads with not a great success.
Next I tried hand sanding with 2000 then 2500 and it went a little better but a lot of work.
Now I am taking off 60% of the OP with 1000 grit 3M wood block. (No 1500 in town)
2000 I work a bit longer on a foam block
Curvy areas get 2500 foam block by hand
Flatter areas get 3000 trizact on my 6" air sander. Wow that stuff is amazing!

The 3000 makes buffing a lot easier.
I am using a white 7.5" med pad damp then spun dry and a bit of product rubbed in then three dots on the pad with the solo 86 2.5 speed pretty slow rpm first pass then I back off on pressure and make maybe 4-6 passes in a 2'x2' area.
I apply product three times doing this.

I'm really happy with it so far from three feet away it looks great.
With 2000 watts of halogen and a flashlight I can see a few light scratches and a few pigtails and a light haze mostly in corners.

I am thinking once the whip car is to this point I could either wax and just drive it or I could buy a DA and maybe maguires 205 with white or soft pads and continue.

Thoughts?

I'll post pics once the wife pulls me away from the car later today. ?
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Old 07-16-2016, 11:15 AM
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I'm not fit to critique your process, not having used SPI clear before. Sounds like you're happy with how its turning out, though.
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Old 07-16-2016, 12:38 PM
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The trunk with 3000 and buffed on one side



I think these are holograms I read about, from moving too fast?



The curves on the rear quarter were a bit more tricky and still have light scratches/ buff marks



Rear quarter still has pig tails I guess I should do another round with the rotary or should I just wait until I get a good DA and different polish/ compound better pads?

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Old 07-16-2016, 06:09 PM
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In my limited experience with polyurethane clear, it is much harder to polish than urethane. Bear that in mind, if it ain't cutting like warm butter.

Second picture looks like the polish isn't quite used up yet. Or theres still polish on the panel.

Third pic looks like you're just not quite finished polishing, thats all.

Fourth pic prompts me to ask- Are you using a soft interface pad with the Trizact? Hand sanding that spot might be best, if those pigtails are not from a clod on the abrasive. A wool pad and some Super Duty compound would probably take care of those if you're into wool.

Theres a LOT of opinions about this stuff but nobody else is speaking up so theres mine! I have buffed plenty but am not fanatical about it, I use whats there and make it happen. Looks like a slick 'bird
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Old 07-16-2016, 06:40 PM
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I appreciate the help

I couldn't find an interface pad in this small town, and west coast Canada seems like it's hard to find pro body paint supplies regardless, easier to buy from Amazon but I was impatient.
The 3M video says it isn't required and the ammo/nyc with the maguires guys on YouTube video says you should use one but I went ahead anyway.

The trunk had quite a few of those pig tails, is this from not using the interface pad? They mostly buffed out.

Maybe I just need to do a better job keeping things clean

Good to know I wasn't buffing long enough, I guess I'm just afraid it will go dry and start to get hot so I'm being a bit shy, but maybe this is why I need to use compound so many times, I will try to go a little longer.

Your tips are a great help, I really appreciate it.
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Old 07-16-2016, 07:15 PM
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Happy to assist

That interface pad IS real important, IMO. 6" DA sanders also can have more or less agressive orbital patterns and that plays a significant part. Cheaper units are generally rattly hogs while high-end DAs buzz softly, y'know?

I see they just use water with the Trizact pads now, and that theres coarser grits in the soft discs than what I was aware of. When I did my GP (in 02), there was also a mild grit paste that was used with the 3000. Made a giant difference but I don't see it in the lineup anymore. It was kinda like blend prep paste, like is used with scuff pads.

Cleaning- Definitely be sure to clean ALL residue from the previous step before proceeding. The paint almost needs to be washed with soapy water between steps. Keep in mind what builds up in those foam buffing pads, and on the Trizact discs. They are expensive but they go fast on big jobs.

Speed and duration... In my experience with modern polishes, I have found that the very last bit of buffing for swirls can be most effectively done at scary high buffer speed. The stuff works off heat, not necessarily just grit like old times. Melting and smearing is really whats going on at the surface in the final phase, rather than milling. Picture that as you go.

The key is to use each dab of compound or polish ALL the way up before slinging another. The foam pads will dang near start to squeak right about the time you're done. Speed up at your own risk, but be advised that polishes can't do what they are supposed to unless they are used fully. In other words, I think guys that wipe off a polish haze when done haven't quite stayed on it long enough.

Compounding 3 times before even putting it in sunlight to look for sandscratches has been my normal. I'd say you're having a fairly normal experience and have some good stuff to work with. Its just damn hard work and its scary. The rule of always using the least agressive method remains king. You're buffing tough paint, and doing alright. Enjoy the hands-on learning!
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Old 07-16-2016, 08:26 PM
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That's great feedback, and you hit a lot of points I have somehow missed in all my reading/searching.
I'm looking forward to trying your suggestions and will get back with pics.
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Old 07-17-2016, 07:09 PM
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As junk mentioned, when using trizac use the soft foamy pad for two reasons, 1 less chance of sanding through sharp edges, and 2 helps keep the curley Qs at bay. Then when you start buffing up the shine, use up all the product prior to applying more, as the shine comes up, you'll find you're increasing the speed, and lowering the pressure, untill you're running wide open, with light pressure, and moving very slowly over the surface.
I've been known to finish up with the buffer running as fast as it will, and a spray bottle of water, just a spritz once in a while, and progressing slowly over the surface. I've been accused of trying to burn it. But actually I'm trying to burnish it. It works for me, anyway.
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Old 07-18-2016, 02:08 AM
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I put these tips to work tonight. Sanded the hood and front quarters last night/ this morning. I still don't have an interface pad but pre cleaned the surface twice with a new cloth and 20% iso water mix and got in the habit of spraying down the trizact often to clean it. Practically zero pig tails now.
I am using a third less product after prepping the pad carefully. And I'm way less shy with the rotary. I used to keep it at 2.5-3 for speed and now I go to 3 until the product is spread then four then the final passes on five progressively getting lighter. I cut the hood into six sections but overlapped them a lot on my first round and I am getting as good of results after my first round than the three I previously had to do.
My new pad is already way more worn looking than the old one and has a slight brown tinge that looks like burning. It feels dry after each section But still lets a ton of product out when I washed it.
The panel is also warm to the touch now as before it was still a bit cold.

I haven't had a chance to see under sunlight as its raining every day. After the one round I can only see light scratches if I wipe it with iso but I'll look closer tomorrow.
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Old 07-18-2016, 06:07 PM
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Pulled it out in the sun and from three feet away everything is great.
Standing with the sun in my face and my nose pressed to the panels I can see 1000 and 2000 grit cross hatching.

The hood and front quarter and door where I kept the rpms up and followed your advice look a lot better then the trunk and roof.

At this point I'm happy but am wondering if I can see those 1000 grit scratches should I

- not be so picky and continue with polish?
- just try buffing them out with the med pad?
- go back and hit it with a new trizact 3000 pad until the scratches are gone and then easily buff those 3000 scratches out?
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Old 07-18-2016, 06:19 PM
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I couldn't get any pics to show the scratches but overall the car looks great

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