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Discussion Starter · #1 · (Edited)
My MK2 didn't look too bad from a few feet away but it's got a lot of small dents and scratches. The roof was developing some surface rust and there are some other spots here and there. After speaking with every body/paint shop in the area and against my better judgement, I decided to try the repairs, bodywork, and paint by myself. I found a perfect hood at the JY and some replacement doors on CL that were in better shape than mine, not perfect though. All the work is being done outside and for the most part, on a gravel driveway :thumbdown:

Last weekend I finally sprayed the first two coats of epoxy after 80+ hours of sanding, etc. Here are some progress pics.

Before work started:





Initially I didn't think I was going to use an epoxy primer so I started body work on bare metal. Not against the rules and lots of guys still do it, but considering that the car is exposed to the elements being worked on outside, I wish I would have waited to do body work until after the epoxy is sprayed only because I've needed to scuff the surface rust every few days. Not a huge deal.

Used 80 grit down to metal, applied filler and block sanded, filler and sanded, then applied glazing putty to fill in the bondo 'pores', then sanded flat again:









Found some rust around one of the rear window. Used a por-15 like product and decided to treat the whole window. I'm just going to leave it on there and paint over it in hopes it prevents those rust-prone spots from being a problem in the future.







Then I decided to shave my rear emblems and window wiper. Without the ability to weld, this is how I chose to do it, I used the pop-out plugs of a conduit junction box and metal adhesive to secure them to the back of the panel, then used filler/glaze on the front. I welcome your trolling this thread about how I'm doing it the 'ghetto' way.







My 30 gal air compressor was waaaaaay too small to power the DA so I bought an electric one at Home Depot. Worked great. Then realized that if some of it was going down to bare metal, might as well take it all down for continuity. This was when I realized I'll end up spray epoxy as well as urethane primer.





The hood alone took me at least 6 hours with the DA to get it down to metal!











I've gotten to know the guys at a body shop literally right down the street from my house, brought them coffee and donuts and picking their brain about what I'm doing right, what's next, etc. Put parts of it back together and drove it down the street to get their opinions on my progress.





And then after taking it all down to metal with the DA, I went over it all by hand still with 80 to get it even smoother and try to leave as little OG sealer as possible. The hood looked like a freshly honed cylinder! Then, because it's been outside, I continued to sand/scuff every part over the next couple of week as I masked and got it ready for epoxy.

















Then, I sprayed for the first time! Made some seriously classic new guy mistakes that I'm now correcting, but all in all, it turned out well. After so many hours of researching every aspect of this project, I decided to use SPI epoxy, urethane, and clear coat. For primers I'm using the Harbor Freight hvlp gun. For $16 it's almost cheaper to just throw them out after each stage instead of clean them, that epoxy is sticky as hell! 1 coat was approximately 1.5 qts of sprayable product. For the first spray I wanted to do it without any type of diy-booth or fans just to see what I'm up against. Got quite a few dust nibs and such but not too bad. Wrapped the threads to my gun's paint cup with teflon tape that ultimately made it out the tip of my gun and into the paint :p Also had the fluid adjust turned so far out that on my first spray, the spring popped it off and it just started dumping paint all over the hood from the tip :facepalm: hmmm... I know there was something else I did that just seemed so stupid, can't remember. Anyway, here it is after blocking again, scuffing, wax and grease remover, tack rag, then epoxy primer:

















That was a week ago and today I started blocking it out again but with 120. It sands a lot better than what I expected, I could have used 220 or even higher. Blocking is easy with the primer because of how glossy it is you don't need any type of guide coat. Once it's all blocked, I'll scuff it all again, W&G, tack, another coat of epoxy, then 3 coats of urethane primer and do it all over again! Hoping to get that sprayed next weekend. There were also some spots that I didn't mask particularly well and left some metal exposed. I bought some rope and shimmed it underneath the weatherstripping to pull it away from the panels so that paint can get underneath, also pulled the windshield molding so that'll be a lot better.
 

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Nice job so far. I have just a few points to mention.

- You should have pulled the windshield. I can guarantee you have similar rust issues around the windshield frame that you had around the quarter windows. I think there's also a good change of rust around the rear windshield frame too. There aren't that hard to pull. The rear windshield and seal isn't too hard to reinstall, but you would need a new windshield as the old bonded windshield will break when you remove it, so I get it if you're on a tight budget.

- You made a good choice of using SPI products. I'm guessing you'll use their build primer as well. I would use a light color of build primer (no need for sealer) over the red epoxy if you are going with a red (or other bright color) single stage or red basecoat. A light color of primer underneath really makes reds more vibrant.

- Doing your filler on bare metal is better than doing it over a layer of epoxy. Some disagree. Dolphin glaze, which sticks to everything, is a good product to use if you find any low spots or other imperfections in your epoxy layer.

- Aircraft remover is A LOT easier and faster to get all the old paint off. You also keep more of the factory zinc electroplating, which will help resist surface rust on the bare metal, versus a DA where it will bite through the zinc layer really fast if you aren't careful.

- You'll probably be ok with the solid backing/filler technique you used to fill the holes in the sheet metal. I do something similar with welding holes, using anything from steel backings to pennies duct-taped in place as backings.
 

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Discussion Starter · #3 ·
Thanks man, I appreciate the input:

- The windshield was replaced a year ago or so and dude who did it told me that there was a little rust in one spot that he sanded and treated but overall was in good shape. I've since decided to remove the exterior windshield weatherstripping so that I can get more surface sprayed and I'll just leave the windshield in and spray around it. It does make sense to remove the hatch glass but I don't have any helpers and I'm concerned with how difficult it will be to put back in. I'll research a little about that. I used some 12 gauge wire I had lying around under the molding so was able to get good coverage underneath. Also, yesterday I decided to remove the hatch so it'll make spraying the rear a lot easier.

- Yes I'm going to use their regular build primer in yellow/buff but Barry recommended to reduce the epoxy and spray a sealer coat on top of the urethane. Apparently it soaks up color and lets more moisture in than epoxy so I'm planning on spraying one coat of sealer, red. I've debated shooting a few coats of white before my base but I think with yellow 2k and red epoxy, I'll get a pretty vibrant red base.

- Cool, I have read a lot of different opinions about where to do filler. I was trying to use as little as possible so every filler spot I ended up with rings of bare metal and with the car just sitting outside I ended up having to scuff the surface rust fairly regularly. Which is fine, but every time I did that, it would un-feather the edge of the filler and with the gloss of the epoxy, I can see kind of a 'crater' where I did body work. It's really not relevant because of all the blocking I'm going to do, but... you know, I'm trying for 'best' at every step.

- I did tons of research on how to strip the metal and aircraft stripper definitely seemed like the easiest route with the best results. Initially I didn't think it was all going down to metal but this whole project has snowballed at almost every step. In the end I decided to continue just sanding it 'old school' if for anything, for the experience. And it was a PITA!

- I'll tell you, that metal adhesive is SERIOUS stuff, those plugs aren't going anywhere...

Thanks for the input and suggestions, keep them coming!
 

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Thanks man, I appreciate the input:

- The windshield was replaced a year ago or so and dude who did it told me that there was a little rust in one spot that he sanded and treated but overall was in good shape. I've since decided to remove the exterior windshield weatherstripping so that I can get more surface sprayed and I'll just leave the windshield in and spray around it. It does make sense to remove the hatch glass but I don't have any helpers and I'm concerned with how difficult it will be to put back in. I'll research a little about that. I used some 12 gauge wire I had lying around under the molding so was able to get good coverage underneath. Also, yesterday I decided to remove the hatch so it'll make spraying the rear a lot easier.
Good call on removing the hatch for that reason. In a pinch, you can push the hatch glass out yourself by setting the outside of the hatch against a wall or something, putting down some pillows or something to cushion the impact of the glass, and pushing on the backside of the glass with both feet. The glass comes out easier than you might think. The same "rope" technique for putting the quarter windows back in will also work for the hatch glass.

- Cool, I have read a lot of different opinions about where to do filler. I was trying to use as little as possible so every filler spot I ended up with rings of bare metal and with the car just sitting outside I ended up having to scuff the surface rust fairly regularly. Which is fine, but every time I did that, it would un-feather the edge of the filler and with the gloss of the epoxy, I can see kind of a 'crater' where I did body work. It's really not relevant because of all the blocking I'm going to do, but... you know, I'm trying for 'best' at every step.
Another thing with 2-part filler is you need to be careful to use enough hardener, or else the filled spot will shrink back and show a low spot once you spray paint on it. I'm not saying that's what happened, but definitely keep that in mind if you use more filler before you spray your primer sealer.
 

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Discussion Starter · #5 ·
Considering how quickly the filler would set up, I'm fairly confident that my mix was sufficient, but that's a good thing to look out for. Plus after sanding it all down today I actually don't think I need to apply any more filler, particularly since I'm planning on blocking it down at least two more times before I apply color :thumbup:

It rained last night and this morning, which was a helpful reminder of how lucky I've been over the past few weeks as I think this was the first rainy day since I started! Unreal...
Between today and yesterday, I spent about 10 hours blocking it all down which gives me a good estimate of how much time to expect when I do it again in the future. I'll be taking a little more care so probably 12 hours is more accurate. After sanding, I went over it all again with a scuff pad. Made some block sanders which worked great.







A pic of one of those 'craters' I was talking about. Actually blocked out fairly well.




This pic is after blocking but before scuffing










And this is what's left of the small covering that I hand my doors and hood under. I might try to use it as a stand for them during paint, we'll see. But for now I'm back to storing them in my living room.
 

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I like your homemade durablocks, I've never tried that one :thumbup:

I have some painting stands I made out of PVC and PVC elbows and couplers. If something is too heavy to go on a clothesline improvised out of rope, I use the PVC stands. It looks like your paint project is going to turn out well, and I respect anyone who embarks on something like this. Properly painting a car yourself is a ton of time, work, and a real learning curve.
 

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Discussion Starter · #7 ·
I like your homemade durablocks, I've never tried that one :thumbup:

I have some painting stands I made out of PVC and PVC elbows and couplers. If something is too heavy to go on a clothesline improvised out of rope, I use the PVC stands. It looks like your paint project is going to turn out well, and I respect anyone who embarks on something like this. Properly painting a car yourself is a ton of time, work, and a real learning curve.
Cheers :beer: Every step of the way I'm trying to ask myself 'is this a corner a professional would cut?' and prevent having completed the project but still saying 'I really should have spent the extra $$$ and time and done that part right.' This was supposed to be a 2 week project while I was on vacation, ha! I'm glad I didn't know how much time and work it would take, if I had, I might not have started...

I was thinking pvc would be a good way to make those stands too, I might still do that.

I've got a question, I'm going to ultimately paint my jambs but they don't need any serious work/blocking, should I still epoxy/urethane them or should I mask around them until I spray a sealer? I'm trying to avoid as many hard edges as I can which would be created at least a little if I just mask them. If I spray them with the primers, how concerned should I be about their thickness if I don't sand them down as much as the rest of the car? (2 coats epoxy, probably 5 coats of urethane before sealer)
 

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Cheers :beer: Every step of the way I'm trying to ask myself 'is this a corner a professional would cut?' and prevent having completed the project but still saying 'I really should have spent the extra $$$ and time and done that part right.' This was supposed to be a 2 week project while I was on vacation, ha! I'm glad I didn't know how much time and work it would take, if I had, I might not have started...

I was thinking pvc would be a good way to make those stands too, I might still do that.

I've got a question, I'm going to ultimately paint my jambs but they don't need any serious work/blocking, should I still epoxy/urethane them or should I mask around them until I spray a sealer? I'm trying to avoid as many hard edges as I can which would be created at least a little if I just mask them. If I spray them with the primers, how concerned should I be about their thickness if I don't sand them down as much as the rest of the car? (2 coats epoxy, probably 5 coats of urethane before sealer)
Hi, I'm a (former) auto body and paint guy, and I'm here to help you on this journey!:wave:

First and foremost, you have obviously done some research, and you're doing a lot of things right! Excellent!

Some key points are:

The metal patching may not last too long... due to vibration from driving, it may develop hairline cracks around the outline of your metal plug. No amount of filler or primer can really prevent this. It looks like you did a pretty good job of prepping the surfaces though. Time will tell.

The craters you are seeing are what we call "a55holes", because they kind of look like them. Those are showing you where your body work may not have been feather edged enough, and will be visible in your paint.. Don't fret, we can save this! I'll get into that a little later.

Use guide coat!!! Do this. Serious. All this work, and not using guide coat is bad juju. It really does help show you anything you missed. Seriously, use guide coat!:sly:


The epoxy primer is really only needed on bare metal, no need to use it when re coating with your surface building primer. If anything, mix a little and spray a light coat on any bare metal exposed when blocking, let it flash, and apply your primer surface.


No need to spray any kind of primer in your jambs. Sand out any imperfections, and seal them at the same time you seal the rest of the car during the spray process. They are not a highly visible surface, and unless your going for a full blown concourse winning restoration, it is a waste of time, and materials. Look up back masking. This will help you keep a soft edge so you don't have lines in your jambs. You can also use jamb foam, which is made specifically for keeping soft edges.

You're using really aggressive grit for your block sanding. 80 grit scratches are difficult to remove. You have to step your grits a hundred at a time. We can save this though. Here is how you should be priming. Anywhere you did body filler, you start spraying primer right on those spots about 6 inches out in every direction. Put it on these areas heavy. Next coat, do the same, but 12 inches out from the same areas. Next coat, prime the whole panel, and repeat once. Using such aggressive grits, is taking most of the primer right back off. You want to leave a lot of it on to fill the imperfections. Next time you block, use 320 grit. If you get a couple nice wet coats of primer on, and use guide coat, you will be able to see any sand scratches, pits etc. You most definitely will need to prime one more time. Last block job should be done with 400, and do it wet. Add a drop of automotive soap to your 5 gallon bucket to help keep things moving smooth.

There is no need to scuff as well as block so long as the surface has been sanded.

Also, your sealer happens when you do the final painting. It should be only one coat, and fairly light right before your base/clear goes on. Same if it is single stage paint. Just enough to make sure your color turns out uniform.

I hope this doesn't come off as critical. You are doing a great job. If there is anything else you have questions about let me know!
 

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Discussion Starter · #11 ·
^^^ Thanks for this, I'm all about hearing from autobody/paint guys that I'm doing it right!

I'll keep an eye out and finger crossed for those metal plugs to stay solid. Your reasoning is primarily why I don't think I'll try to shave my rear body lines above the bumper by filling them with bondo. Any thoughts about this though?

Yeah, those a55holes definitely are, but completely my fault. I had filler on those spots and flattened them out perfectly, but after sitting outside for a few weeks and having to scuff the edges, I didn't put another layer on and then block before spraying :thumbdown:. Those are one of the reasons I blocked the epoxy so heavily.

I've got guide coat and I will definitely use it when I spray urethane, but the epoxy is sooo glossy, I didn't need it!

I've got enough epoxy left to mix for at least another two coats so I'm just going to spray the whole car again for a continuous surface. I'm trying to limit as many 'edges' as possible, feathered or not, because it seems that those could be possible areas to peel over time.

Thanks for that about the door jambs, that's what I was thinking/hoping, that I wouldn't have to spray them. I've been back-masking but not doing quite right apparently (one of the FNG mistakes I made) so I'll work on how to do that properly for the jambs for rest of the primer phase. And by the way, FNG stands for f****ng new guy.

The SPI tech sheet said to prep the surface with 80 before spraying epoxy and I had a lot of body guys tell me the same thing, that it's too coarse but seriously, that epoxy filled them super well! Only one scratch came through and that was because I accidentally scored through some filler with the edge of my block. But I definitely agree that 120 was too strong for blocking, I was just so surprised at how well it sanded! I'm planning on using either 220 or higher for the next blocking but I probably will use 320 and then definitely at least 400 before color.

Scuffing after sanding is mainly just to feather panel edges and give texture to the low spots that I left behind so that the next spray will stick to them. It's kind of a nice way to get zen with it too!

Yeah, I'm planning on spraying the sealer after all blocking and primer is finished. Barry at SPI was saying the urethane primer should have a sealer on top of it to keep moisture and color from being absorbed by the urethane. And spraying another coat of red before spraying red doesn't seem like a bad thing either!

Not critical at all, very appreciative of any/all information I can get! My only question left is about what brand of basecoat to use but seeing as how that's probably the most over asked question on every forum I've read, I'm debating whether I want to turn this thread into one of those :D But I'm leaning towards using Wanda paint, it's about $400/gal for LY3D compared to $1200 for PPG DBC (no way!) or $250 for Omni (I don't think so either). I've gotten quotes for pretty much every other company offered near me and they all hover around either $250 for the budget line or $1200 for the high end. $400/gal seems like it may just be Goldielocks' porridge. And the SPI/Wanda combination has great reviews.
 

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Discussion Starter · #12 ·
Well it's been another day of learning from my mistakes. Sprayed 2 more coats of epoxy but sprayed the first coat too wet and got a lot of runs, I think I was too confident and didn't pay enough attention. Then sprayed urethane. I spoke with Barry @ SPI and he suggested the following timeline for Seattle weather 75+/- degs: 9am spray 2 coats of epoxy, wait 4 hours and then spray urethane. This way the epoxy cures to the urethane and there's chemical adhesion as well as physical with enough time before it gets humid out (as the sun goes down). I used a different HF gun for the urethane because it had a 2.0 tip instead of a 1.4. This gun was a siphon feed and I struggled with it. Had to learn to position the stem so that it feeds off the bottom when tilted and adjusting fluid level/fan didn't seem to make much difference. Also made the mistake of mixing more urethane than I needed per coat, it sets up really quickly so I essentially lost about 1/3 of my product because it was too thick to spray and it plugged up my gun. So... the moral of the story is only mix what you can fill in your cup, remix when you refill. I did that for the subsequent coats and it went so much smoother. In the end, I got some parts coated 3 times with urethane but most of it just twice. I'm going to wait until the weekend and then start blocking, will definitely need guide coat for the urethane. I anticipate needing to spray at least 3 more coats after I block it and I might even do it again after that! Then sealer/color/clear.

Alright, pics or it didn't happen:



The worst of the runs:










Urethane in Buff/Yellow:






















And the piece I've been most concerned with getting just right. Nailed it.
 

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Discussion Starter · #13 ·
Started blocking the urethane. It sands sooo well. I think that's another advantage of having sanded the whole car down to metal, it helps me appreciate how much easier everything else is to sand! But blocking with 400, I was concerned with it being too smooth because I'll be spraying more primer over it. After a bit of research, sounds like I should be hitting it with 220+/- to straighten it out and then my last blocking should be 400+ before sealer. So for sanding this first 'run' of urethane, I'll use 220. I'm still going to use guide coat but the layer of epoxy under the urethane will be my bottoming out point. Then my subsequent sprays of urethane I'll block with the intention of getting a consistent layer over the whole car. But for now, I'll block just to get rid of all the imperfections mainly from my epoxy coat underneath and low spots. Quite a lot of runs!





 

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Discussion Starter · #14 ·
More sanding. Blocked it all down with 220, exposed the poor spray job I did with the epoxy, but it's smooth again now. I'm waiting for more urethane to get shipped so I'm stalled for another week or so, I might mask it off again just to give me something to do. My plan is to spray the low spots a couple of times with the urethane, then spray the whole care with another 3 coats, block it out fairly heavily with 220 again. Depending on how many low spots I have (if any, fingers crossed), I'll spray another 2 coats of urethane and block it with 400. Pics in its current state:













Pic of guide coat before blocking










 

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It looks to be like you're having some trouble with consistent spraying in terms of even coverage and material thickness. That's evident by the runs in the epoxy layer you have pictured. Have you tried dialing back the feed knob on your primer gun, and practicing using a consistent speed, distance, and spraying motion?

You're also spraying, or plan to spray, a lot of primer surfacer. I get that the first few coats of surfacer seemed to have been to compensate for the uneven epoxy layer, and a lot of surfacer material has been removed now, but I'd advise you not to spray too much additional surfacer. You don't want too thick of a total primer build, because then you're wasting material and potentially (and counter-intuitively) might be risking durabilty. I wouldn't go hog wild with the clearcoat either, because even though a thick clearcoat layer is great for durability, it can be hard to spray clearcoat thick without introducing striping or having foreign contaminates that will be impossible to remove if sprayed over with multiple additional coats of clear. You might be surprised how many dust nibs and the like can show up in a base/clear job that you sprayed in a booth that you thought was squeaky clean.

Also, don't depend on surfacer to fill low spots unless the low spots are literally only like 1-2 mils deep. Deeper low spots in your epoxy/surfacer layers is exactly what a 2-part finishing glaze, such as Dolphin glaze, is designed to fill. Because you will be spraying a sealer layer, the finishing glaze will not affect your basecoat or clear. I would highly consider not spraying more than 1-2 coats (or 2-3 mils) more surfacer, just so you have a consistent substrate, and instead use finishing glaze if you need to fill low spots over 1-2 mils deep.

I'm a fan of Matrix basecoats and clears, from a cost:quality and ease-of-use standpoint. I've never read much about Wanda, but $400 for a gallon of their basecoat sounds tempting if it does indeed play nice with quality clearcoats from other makers. Yeah, basecoat can be really expensive and there are much better values than the top-of-the-line names like PPG or Glasurit, which are at the same time much higher quality than the Omnis and Nasons.

In terms of your plans for basecoat and clear, are you building a DIY booth or are you getting hooked up with a professional booth?
 

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Discussion Starter · #16 · (Edited)
Thanks, that's helpful info about not spraying too much primer. I have 'euro glaze' that I used on top of bondo, is that the same as dolphin glaze? And can I apply the glaze over primer or would I need to sand it back down to the epoxy coat before laying it on?

Definitely was inconsistent with the last spray. The first few coats of epoxy I sprayed really well but wasn't very focused the second time around...

As far as a booth goes, I've debated asking the guys down the street if I can use/rent their booth for color/clear, but I've made it this far on my own and I'm more inclined to keep going to see how good I can get it. If I do, then I might try to make my own booth. I'd lay plastic on the ground under my car cover and enclose both sides with plastic, then hang two fans on either end, one pulling in filtered air and one pulling out vapors, etc. What do you think?

*Edit: after doing some research, it looks like a 2k glazing putty can be used on top of a 2k urethane primer without issues. However, the last post of this thread makes a good point, that if the low spots aren't too low, it may be better to just fill them with primer. I'll give them a feel tomorrow and make that call, I believe all of my low spots are fairly shallow.
 

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Thanks, that's helpful info about not spraying too much primer. I have 'euro glaze' that I used on top of bondo, is that the same as dolphin glaze? And can I apply the glaze over primer or would I need to sand it back down to the epoxy coat before laying it on?

Definitely was inconsistent with the last spray. The first few coats of epoxy I sprayed really well but wasn't very focused the second time around...

As far as a booth goes, I've debated asking the guys down the street if I can use/rent their booth for color/clear, but I've made it this far on my own and I'm more inclined to keep going to see how good I can get it. If I do, then I might try to make my own booth. I'd lay plastic on the ground under my car cover and enclose both sides with plastic, then hang two fans on either end, one pulling in filtered air and one pulling out vapors, etc. What do you think?

*Edit: after doing some research, it looks like a 2k glazing putty can be used on top of a 2k urethane primer without issues. However, the last post of this thread makes a good point, that if the low spots aren't too low, it may be better to just fill them with primer. I'll give them a feel tomorrow and make that call, I believe all of my low spots are fairly shallow.
Are you talking about Evercoat's product when you say "euro glaze?" If the packaging says something like "polyester glazing putty," and its catalyzed by a hardener, that product would be comparable U-pol's dolphin glaze. As a hint, when the instructions or tech sheet says that a product sticks to "OEM finishes," that pretty much means it will stick fine to properly cured 2k epoxy or surfacer primers. The dolphin glaze sticks to everything, from plastics, to aluminum, to bare steel, to e-coated steel, to primed surfaces, and even to wood; its good stuff. Whenever in doubt, its simple to just test a tiny area and see how the product sticks before you commit to filling more spots.

Yeah, if the low spots aren't too low, as in only 1-3 mils like I mentioned, by all means you can fill them with surfacer. You kind of have to use judgement there as you can't really measure that depth. I go feel. After I think I'm done sanding primer I feel up the surface. If I can feel the scratch or low spot with a fingernail or fingertip, it gets finishing glaze. If its something that you can't feel, but can barely see in good natural light - like tiny pin holes, small waves, sanding scratches, its probably only a few mils deep and more surfacer will fill it. That's simplifying things and is where judgement and experience comes in to play. That's another reason why its good to do your prep with good sunlight, as there are some imperfections that you just won't see under garage fluorescents or LED lights.

I built a simple positive-pressure, free-standing DIY booth, with just one big whole-house fan (rated up to 2500 CFM) pushing air in and exhausting through some filter material on the opposite side. You don't really need an exhaust fan if you have a sufficiently powerful fan for the booth's volume, but some people might disagree. Others put a lot of thought and effort in to building complex down-draft DIY booths, with ducting and cage fans that are guaranteed not to spark at startup, but you really can get away with a simple positive pressure DIY booth. Mine is basically two 10x10x8 foot modular sections that can be joined together for something like a whole car, or I can use just one 10x10x8 section for painting parts. It works great and can be broken down for storage. The only drawback is that it takes a while to put up the structure and all the plastic sheeting. If you have permission to put a booth up in a garage, or carport, you can get away with a lot less framing material.

For tips on a DIY booth, I'd say use at least 3-mil plastic sheeting so it will be unlikely to rip. Be sure to engineer some sort of zipper for the door, because taping the entrance up each time you get in and out is a huge pain. PVC or electrical conduit are economical materials for the frame, but not confidence inspiring if you get any wind over 10 MPH or so. Here's the best picture I took of my version 1.0 booth, in 10x10x8 foot mode, during a motorcycle-parts painting session. I have since upgraded to using lumber for the frame and a wider entrance with a zipper to allow driving a car in and sealing the entrance easily.

 

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Discussion Starter · #18 ·
Cool, thanks for all of this. Yes, it does say polyester finishing putty and a pdf about it can be found here. Looks to be very similar to dolphin glaze, I'll probably use it on the primer in at least a few spots. Not sure how I missed it but there's a fairly large dent still in the bottom of the passender's door, only noticed it from one of the photos oddly enough.

That's a cool booth and I think I will do something fairly similar to it. My car cover has fabric ends that I removed for more space but I'll probably put the front one back on (with the zipper) and maybe use thick plastic for the back so that I can cut a space in it for a fan, if I can get away with one fan like you do, sounds good to me. Was yours mounted up high? Or low? Does it even matter?!

The weather has turned recently around here and I'm starting to wonder if I'm about to miss my window to spray at proper temps. We'll see how the next few weeks go and I might just need to plan ahead and be prepared for projected warm weather days. I also snagged an engine hoist from a buddy that needed it out of his garage which may very well have sealed my fate to remove my engine and clean/paint/tuck my engine bay. It is kind of a mess under the hood. Problem is that I don't have any space for storage except my living room so unless I get another car cover, it might be better to finish the exterior paint and reassembly before going too crazy...
 

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That's a cool booth and I think I will do something fairly similar to it. My car cover has fabric ends that I removed for more space but I'll probably put the front one back on (with the zipper) and maybe use thick plastic for the back so that I can cut a space in it for a fan, if I can get away with one fan like you do, sounds good to me. Was yours mounted up high? Or low? Does it even matter?!

The weather has turned recently around here and I'm starting to wonder if I'm about to miss my window to spray at proper temps. We'll see how the next few weeks go and I might just need to plan ahead and be prepared for projected warm weather days. I also snagged an engine hoist from a buddy that needed it out of his garage which may very well have sealed my fate to remove my engine and clean/paint/tuck my engine bay. It is kind of a mess under the hood. Problem is that I don't have any space for storage except my living room so unless I get another car cover, it might be better to finish the exterior paint and reassembly before going too crazy...
I have the fan mounted up high for my booth. The problem with putting the fan low is that overspray particles, dust, and other trash tends to settle on the floor and with the fan down low, the airflow will swirl all of that trash around worse than usual. I guess that brings me to the next point: be sure to clean the floor and walls of your booth before you start spraying. Even just walking around in there can kick up a surprising amount of contaminants. Keep your painting suit and other PPE clean. Have a good particle and moisture filter for your gun's air supply. Use fresh masking on the car if the paint you sprayed before has had a chance to dry. It really is a special kind of frustration when you do everything else right and some conspicuous junk lands in your still-tacky basecoat or first coat of clear, because you overlooked some cleanliness detail. You probably will get at least some contaminates anyway - even big-money pro booths do, especially in clear coat which can stay tacky for an hour or more - but clearcoat contaminents can be wetsanded out pretty easily (or at least made virtually unnoticeable) as long as they aren't totally encapsulated by more clear coat.

I also have my air filters up high on the exhaust side. I've never tried putting the exhaust down low, but doing so should help with forcing more overspray particles out of the boothspace instead of those particles settling on the walls or the floor.
 
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