Topic: How to paint with Urethane based products.

[manjisann]

I'm starting this thread to try and share the tips and tricks I have learned and the mistakes I have made and hopefully you can avoid. I've got a build thread that covers the motorcycle itself, this will deal mainly with the body work and painting side of it.

Before I started out to learn how to use urethane paint and do body work I did a ton of reading. I spent 5 months or so reading and dreaming. I read a lot of books, a couple great posts on this forum, and a lot of Google searching. There were many things that factored into my final decisions, things like cost, quality (or at least perceived quality), ease of use, and some of it just tossing the proverbial coin.

A few books I highly recommend at least checking out from the library if not just outright buying them, are any of the painting books by Joanne Bortles. She paints mainly motorcycles for a living, and of all the books I read hers were the most in depth on the little things and had great pics on how to do things.

OK, lets get started.

I chose to use Kustom Shop paint (you can find it at tcpglobal.com) because in all my researching I couldn't find a single negative thing about them. In fairness I couldn't find anything about them much at all, but my reasoning was nothing travels faster than negative reviews so if I couldn't find any, then that was a point in their favor. Cost was also a big factor. They cost about half of what House of Kolor does, and since at the time I was on a budget (that was overshot by a lot, but that's a story for another thread) this was a big factor. Also, they have a lot of products that are Isocyanate free. In all my searching I learned that a lot of the Urethane based  products have this Isocyanate in them, and it turns out it is a derivative of Cyanide. If inhaled it will destroy your kidneys in short order. No, I don't know how much you can get away with breathing, but the older I've managed to get the more I realize my own mortality. So, definitely a bonus.

Alrighty, something I just learned today, aparently the Urethane clear catalyst is what contains the Isocyanate. I already knew this, but it can also be absorbed through the skin, so when spraying the clear, wear a Tyvek suit!

Since I was using the Kustom Shop stuff I bought a DVD by Ed Hubbs ( I think he's the creator of the paint line) and he walks you through the steps from basic metal prep and body work all the way to clear coating. It was very helpful in giving me the basics to build on. He also has a lot of airbrushing vids on Youtube that are pretty cool.

Now that I had decided on what paint to use I needed to figure out how to apply it and where to do so.

Where:

Last year I sprayed some exhaust pipes using a couple cans of VHT high temp paint. The pipes came out looking pretty good, but the garage was covered in this lovely dusting of matte black paint. I had to mop it a couple times and I still find smudges of it. Plus the garage doubles as a woodworking shop and whatever else we need, so dust was a major concern I had. I didn't want to go through all the effort of doing a top notch paint job only to have some random booger appear in the wrong spot while it was drying. I decided I needed to construct a paint booth. After a ton of research and a few posted threads here (thanks to those who answered!) I decided on a basic design and filter system.

One thing to consider when venting your booth is that the stuff you are spraying has the potential to be flammable. I am not sure what all it would take to make it light up, and I wasn't interested in finding out. So having a fan with the motor in the center located on the exhaust side, sucking the air out was not ideal. I located the fan on the intake side right behind some paint filters. I've heard of people using the air filters you put in your furnace with good success, but since I'm me I chose to buy the floss type paint filters. I found them on eBay, something like 50 of them for $30. Thats more than I'll need for this project, but hey, there will be others   . I'm just using a $14 box fan that we found at Lowes to push the air in and so far it is doing a decent job. You don't want a ton of air movement as it will stir up dry overspray and get that on your piece, but you do need it to move the cubic feet or your booth several times in an hour otherwise you'll be painting in a haze and your part will not cure properly.

Here's a few pics of my paint booth.

Pic 1:

Here's the exterior of the paint booth. It's constructed of 2x4's, 6mil Visqueen (painters plastic) and uses tarp zippers for the door. It's relatively air tight and keeps the overspray from getting on everything else. It's 7ft x 7ft square and about 6.5 feet tall. Believe it or not it is too small. When I went to paint the frame it was quite interesting getting to all the angles without bumping the frame. If I ever get the chance to build a permanent one it will be at least 10ft x 10ft square, and I'd like to have the floor made out of some sort of grating and have the exhaust filters located in the floor. The advantage to this would be less likely to kick up dust due to moving around. We'll see if that ever happens   I have lights on every side and a couple on top. It does a pretty decent job of lighting up anything I'm working on.

Pic 2:

Here's the intake side of the filter. As you can see it's just a simple box fan. I built a square tube that channels the air and a frame to put the paint booth filters in. It works fairly well, again, I'd make a few changes if I ever built a permanent one.

Pic 3:

Here's the inside, I have a "bench" which is just some 2x4s that are screwed together. This gives me somewhere to put the spray gun while I get the paint filter ready and also somewhere to put the empty containers and a few common premixed colors.

Pic 4:

I hung the little fiddly bits from these pieces of string with little bits of hanger bent into hooks. It worked pretty good. Ideally you'd only have one row so that when you are spraying your clear you don't have to worry about overspray getting on your already cleared parts. When I hug the frame I used some chain to go through the steering tube and the passenger peg mounting holes. It worked pretty well, though I had to touch up some areas due to missing them the first time around  

Pic 5:

Here is my test spray paper. Every time you shoot paint you have to disassemble your spay gun to clean it. The first few times I put it together and would either have the pattern to wide or too narrow, too much or too little paint, etc. This gives me somewhere to test the spray before I spray my part. I've done well over 50 spray sessions and I use it every single time. It also allows me to test how fast I need to move the gun to get the correct coverage without getting runs.

I'll be going over more later, but it's getting late so I will call it a night.

Brandon

[manjisann]

How To Apply It:

I did a lot of research on this part. There are many different air compressors, air filtration systems, and spray guns to say the least. Then you have to worry about personal safety.

Safety

Before I go any further I want to point out, I have absolutely no special training on any of this, only what knowledge I gained from reading books and the internet. Any do it yourselfer stuff I show, while I firmly believe to work and be safe, you use at your own risk!

No matter what paint product you go with, and no matter what is in it, you'll want to wear some sort of respirator. I'm sure all of us have used spray paint and not worn a respirator. As I mentioned before, I sprayed some pipes in a garage and barely had the door cracked. In addition to being rather hazy, it wasn't really good for my lungs and brain cells I'm sure. For any paint other than the stuff with the Isocyanate in it, you can most likely get away with a cartridge respirator, provided you change the cartridges regularly.

When I was first planning this whole adventure I read that ALL urethane based paints have Isocyanate in them. So I researched what my options were for breathing filters. I tried and I tried to find a cartridge filter that said it would handle Isocyanates, but couldn't. Everything I read said that a fresh air mask was the only way to deal with this potentially deadly chemical. So I looked up fresh air systems, but couldn't find any in my price range (less than $100 was my range, the lowest I found before giving up the search was $500, but that came with it's own compressor). At that point I faced a choice, I could either give up on using this paint system, or build my own air mask. I chose the second option  .

I bought an Australian made gas mask, I believe the manufacturer is SEA, and I think it cost me around $40 US. It didn't come with the funny looking filter cartridge, but I didn't care as I had no plans to use it. I used a male to female pvc coupler ( I believe it was 1.25" but don't remember for sure) that fit in the filter hole. I roughed up the sides a bit with sand paper to give the epoxy something to bite into, and used two orings to help keep the coupler evenly spaced in the hole. I fitted the two orings on the coupler on the outside of the female side. I seated one as far up as it would go and the other down near the bottom of the coupler, and used a popsicle stick to seat it at the bottom without popping it off the coupler. This served two purposes, first it kept the coupler evenly spaced from the sides of the hole, and second, it kept the epoxy from seeping past the coupler into the airway and possibly causing problems there. I then mixed up the epoxy and used the popsicle stick to spoon it into a syringe which I then used to fill the hole around the coupler. It worked pretty well, and once it was filled to the top of the hole I pushed the second oring into it and used the popsicle stick to make it as level as possible. I let this dry overnight just to be sure it was good and solid. When I tested it to see if the coupler would come out it wouldn't, the coupler and epoxy would spin around in the hole. At this point I realized that scoring the sides of the hole would have been a good idea, so if you do this be sure to score them. It wasn't too huge a deal, I just used a bit of epoxy covered the top oring and went down the sides of the top of the filter hole a bit. Spinning problem solved.

I then used a 90 degree pvc elbow, some air hose, a threaded brass adapter to fit the hose to the pvc elbow and a regulator. This really doesn't use a lot of air, maybe 5psi continuous, it's a little noisy but nothing really annoying in my opinion. Best of all, IT WORKS!!

See pic 1 for pics of the Fresh Air Mask on the left, and a cartridge filter mask.


Air Delivery:

You are going to need an air compressor. How big of one depends on how much painting you are going to do, and how close an eye you want to keep on your regulator. If your machine can't deliver consistant pressure to the gun, your spray pattern will not be consistant and that is bad. I'm using two air compressors hooked together by a manifold I made which then hooks into a air\water separator, which I bought at Harbor Freight. I did this because in addition to painting I was also sandblasting and that takes a lot of CFM. When I set up my own garage the way I want, I'll have a compressor with at least a 5hp belt driven motor (they are a lot quieter than the direct drive ones, I'm using both) with at least a 60 gallon tank, and I'll probably add another auxiliary air tank just to be safe. Thats just me, you don't need it that elaborate. You do want to be sure it can deliver consistant pressure to your gun, and if you are using one, your fresh air mask.

Pic 2 shows the two compressors I am using. The belt drive one is a 220v system, I'm not entirely sure of the advantage of 220 over 110, but with the way this garage is set up I had to run it this way or else blow a breaker every few minutes 

Pic 3 shows the air/water separator and air manifold I put together. This allows me to have 2 dedicated hoses in the spray booth and one with an air gun on it to blow off dust when I am sanding stuff. The big red thing you see on one of the hoses is a dessicant snake, it filters out the water vapor that the water separator misses.


The HVLP Guns:

When using HVLP guns (stands for High Velocity Low Pressure) you use only about 30psi of air pressure to the gun. By the time it comes out the tip it's only 10psi. The advantage of this set up over the old school sprayers that used around 60psi at the gun is there is less over spray. Less overspray means more of the paint hits the project surface and sticks, which means less waste. It's really nice.

I'm not going to go over the guns controls, as they vary a bit from manufacturer to manufacturer. As for price, you can pay anywhere from $40 all the way up to over $500 per gun. The difference between the $40 and $500 gun from what I am told is atomization, or how finely it can atomize the paint. From what I understand, seeing as how I've never seen a high end HVLP gun used, it equates down to sanding. The less expensive guns (I am intentionally avoiding the word cheap(er) ) don't spray as fine so the paint doesn't go on as smooth. For a pro sprayer where time is money, the less sanding they do the better I'd imagine. For us home users, unless you are blessed with a big wallet, the less expensive guns work just fine. As of this writing I've purchased a set of guns from TCPglobal, it came with 2 full sized guns and one smaller touchup gun, and I purchased a second touchup gun for spraying only clear (I'll explain why later.) I paid about $100 for the 3 gun set and $45 for the single touchup gun, and in all honesty the two touchp guns appear to be nearly identical. I wouldn't be surprised in the least if they were made in the same factory. The only difference I've found is the one from TCPglobal says to use 45 psi to the gun (weird, but instructions are meant to be followed, sort of  ) and the one I bought locally says 21psi to the gun.  My point is, provided there was reasonable attention to detail, any gun will most likely work for you.

Pic 4 shows the three guns I use regularly. From left to right, one of the TCP full sized guns with a 1.8mm nozzle, center is the new touchup gun I had just picked up earlier that day with a 1.0mm nozzle, and left is the touchup gun that came with the TCP kit and it also has a 1.0mm nozzle.

The big gun with the 1.8mm nozzle I use for spraying the high build primer, and that is all I use it for. The biggest problem I've run into with this gun is it's size! For painting a car or other large project I'm sure it is great, but for painting a motorcycle it's a bit on the large size. I'm not sure if the 1.0mm touchup guns would be able to properly atomize the high build primer or not. I'll try it next time I have to spray some and include the results in this thread.

The center "shiney" touchup gun with the 1.0mm nozzle I will be using to shoot the clear coat ONLY!! I've learned the hard way that no matter how hard I try to clean my gun there are always going to be errant particles of paint that come out when I clear coat  and lets face it, I'm using this type of paint to try and replicate a very nice finish. Stray sparkles in the clear will ruin that. If you can afford it, I highly recommend dedicating a gun to clear coating only, it will save you a lot of heartache.

The touchup gun on the left as you can see from the pics has seen a lot of use. Believe it or not I clean it after every coat I spray, but it still looks well loved  It also has a 1.0mm nozzle, which seems to be standard on these lower priced touchup guns. I believe TCP carries a 1.2mm nozzle setup, but I don't have it so I can't say how useful it is. The biggest downside to using this as my main spray guns is if I wanted to spray large flake paint, I probably couldn't through the 1.0mm nozzle. I'd have to move back up to the larger bodied gun and use a 1.4mm tip at least.

The funny looking white thing on the bottom of the guns is another dessicant filter. These ones are great as they will change colors when the dessicant is spent and then you know to change them. The big gun also has an air regulator on it still as I haven't removed it yet. I decided to install the regulator on the airhose side so I didn't have to have so many of them.

Cleaning the guns:

As for cleaning them after spraying, I use Laquer Thinner. I have an empty 1 gallon metal paint can I'll empty any remaining paint I don't want to save in it. I squirt some thinner into the cup, put the cap back on, plug the hole in the cap and shake twice. I then take my finger off the hole, replug and shake again twice. This may seem like some sort of ritualistic dance to the gods of paint, but trust me it isn't. I've found that if I shake more than twice the pressure from the evaporating laquer thinner will blow dirty crud everywhere, which isn't that much fun. I then dump the dirty solvent into the paint can, spray in some clean solvent, hook it back up to the air line and spray the clean solvent through the gun into the paint can until it starts spraying clean solvent. Be sure you are wearing at least the cartridge respirator, a lung full of this crap will have you hacking for a bit, and is definately not good. Once it starts to spray clear you can dump any remaining solvent cleaner our, or just finish spraying it out.

I then take off the cup and cap, clean them both as good as I can get them, and set them aside. I have the little mason jar you see for the filter that is in the guns neck, the atomizer, and the needle seat. I'll take all these things out of the gun, put them in the solvent, swirl it around a bit, and then pull them out. I use the squeezy bottle to spray solvent through all the passages in the atomizer and needle seat and to spray off the filter. Set these aside.

Remove and wipe off the needle real well and set it aside. Using Qtips (I recommend using the name brand ones as the cheapie ones seem to leave fuzzies behind) clean out the neck of the gun, and the front where the needle seat went. I then will spray some thinner through the gun using the squeezy bottle.

I use the little brushes you see (pic 5) if any of the orifices get plugged up, especially on the atomizer.

You don't have to clean the gun in this order, it's just how I do it.

If anyone has any questions, please feel free to post them. I'm trying to cover all the questions I had, but I'm not sure I can remember them, or you may have one I didn't.

Brandon

[manjisann]

You will need to either scuff up the old paint so the primer will adhere, or even better, remove it. There are many ways to remove it, chemical strippers, sand blasting, or abrasive sanding.

On the fuel tank and fenders I chose to use a 3M nylon stripping wheel. I found a version of these at Harbor Freight and bought it figuring it would be the same thing. It did a good job but wore out fast and became very flimsy after a while. The 3M one has remained rigid the entire time and has lasted through 2 tank strippings, one of which was very thick. (see pic 1 for the strip wheel)

Body filler is a lot like makeup, too much and whatever you are trying to do looks like a clown, but the right use of it and you will have a super model (one that eats  )

If whatever you are trying to fill in is more than an 1/8 of an inch deep, you will need to do it in multiple layers. If you don't you can run into adhesion problems, pin holes and other stuff you won't enjoy. I know the metal workers out there are ready to burn me in effigy for suggesting we use body filler instead of hammering or pulling out the dent, but if you lack the metal working skills necessary to do this you may really want to consider the dreaded Bondo Fix. In my opinion, where this all went wrong was using body filler to do something it was never meant to do, and that was cover over rusty holes in fenders and body panels. If you have rust or holes you need to address those before using the body filler.

There are as many types of filler as there are fish in the sea... OK, maybe only a few dozen, but still plenty to choose from. I've been using two different ones.

Pic 2. Evercoat and All Metal body fillers

I use the all metal if I need to build an area up a lot, like in the case of my fuel tank. Remember how I told you if you don't have the appropriate metal working skills that body filler may be the route you want to take... well I don't have those skills.

Long story short, in the course of trying to remove a creased dent out of the shoulder of an otherwise perfectly sound tank I tore some holes in the metal. In order to fix this I ended up cutting out the entire dented area and stitch welding in a patch piece. Fortunately my tank is sheet metal so I could do this. I was able to get it water tight, but I wasn't able to match the exact contours of the piece I had hacked out. My only option was to use body filler to build this back up.

I would put a layer of All Metal on, use a cheese grater to shape it down a bit, add another layer, shape it, so on and so forth. Once the basic shape is roughed in I started sanding. I used 60 grit paper wrapped around a sponge sanding block (see pic 3)  that you can pick up at your local hardware store. It works great for this. To ensure I matched the other side as closely as my meager talents and skills would allow I used a contour guide. (See Pic 4.) This has a bunch of little pins that will slide through the middle. They are under tension so they don't move freely you do have to press on them a bit. I would push this on the non buggered side and then flip it over and check it against the other side. This would show me where I was built up to high, or where I needed more body filler.

Once I had the filler built up so it was really very close to the other side there were still pin holes in it. This was due to it being fairly thick and when it was mixed air would get introduced and dry in there. As I sanded the filler down the holes would show up. The All Metal is too thick to fill in pin holes reliably, this is where the Evercoat comes in. It is a glaze/pinhole filler.  When it is first mixed it is pretty runny and will fill in the pin holes.

Both of these body fillers have a catalyst that is added, and once mixed in you only have approx 3-5 Min's to use whatever is mixed before it hardens to much to spread. It takes approx 30 Min's after that before it can be filed down with the grater (see pic 5).  In the beginning I was using a plastic mixing board that I would have to clean off after every use. This was really a pain so I bought some onion paper. This paper won't absorb any of the chemicals in the body filler so it won't mess it up, but when you are done you just tear off the top layer and you are ready for the next batch. (see pic 4) The body filler is the large blob and the activator is the white ribbon across it. This is the approx mix ratio for most of these, but be sure to read the instructions of whatever you are using.

Just a heads up, I'm told none activated fillers will shrink, which is a pain after you just got them to look so good.

[manjisann]

If anyone else who has experience with urethane painting wants to include their experiences or tips, please feel free. The purpose of this thread is to try and consolidate some of this info into one place, and answer some questions that there may be. I know before I started I had a thousand questions, and now that I've started, it's down to 999  If you want to pm me with your tips or experiences, I'd be happy to add it to the appropriate section of this post so it all kind of flows, and I'll definately give you credit for the info. I'm looking for things you've found that work, things that don't work, paint systems you've used and what you thought of them, equipment you've used, etc.

Thanks, and if anyone finds this info useful, please feel free to reply and say so. Otherwise I feel like I'm just writing to myself 

Brandon

[manjisann]

NOW to the whole reason you have been reading this thread, the painting portion!!

I've read it a dozen times at least, if not more. A paint job is only as good as the prep work that went into it!
I can tell you right now, this is 100% true. The more time you take to prep the surface and make it as even and smooth as you can, the better your spray job will look. If you do it right there will be minimal wet sanding in between clear coats, and when you do clear it, you will almost stop breathing from how incredible the clear looks!

OK, the painting:

After you have finally got the body work where you want it, blow the surface off with a clean air source. If you haven't set up some decent filtration of your air you are just setting yourself up for problems. I live in a desert and I still have to empty my water separator and air compressors.

Now wipe the surface down with a quality wax/grease remover. At this point if you haven't already been, I'd highly recommend wearing either Latex or Nitrile disposable gloves. You do not want to get your body oil on the surface or you will cause yourself no end of grief! After you have wiped it down, you can very very lightly tack it down. If you press too firmly while tacking the surface down you will transfer some of the goo on the tack cloth onto your project and you will have problems.

At this point I transfer the item into my spray booth. Unless you are absolutely sure your surfaces are smooth, you'll start off with a high build primer. I know some people will seal the surface with an epoxy primer first to cut down on the risk of rust, I don't. I know I'll be shooting the full coat quickly enough that I don't think rust is that big of an issue, but only time will tell.

High build primers purpose is to help level out very minor surface hills and valleys. If the surface is too uneven you won't get it to level out without a ton of primer, and you really want to avoid that. While it is true that a custom paint job is frequently thicker than an oem spray job, you don't want it to be too thick, and primer is usually one of the major contributors (at least it was on my first spray job on the tank).

At this point I want to point out that every paint system has it's own set of flash times that need to be followed, so be sure you get the Tech sheets for what you are spraying and study them. If you have any doubts or questions, ask the store you bought it from or contact the manufacturer. Trust me, you don't want to screw this up, it is no fun to remove an otherwise beautiful paint job.

For the system I use, I mixed the primer with it's catalyst, using the proper mix ratio. There are two ways I know of you can do this, there are disposable cups with the different scales on them (see pic 1). These are great, as when you are done you just chuck them and there is minimal mess to clean up. I've also heard of metal stir sticks that have the scales on them, but I haven't used one.

Keep track of what mixes with what and don't have anything you aren't using on your table. After you have mixed the paint you only have a certain length of time to use it before it will begin to cure and ruin your spray gun, this is know as "pot life." The primer I was using had a pot life of 2 hrs at 70F, but I have seen them as low as 20 Min's once the catalyst is mixed. You want to be done spraying and cleaning your gun before this time elapses or you will be buying a new gun.

Spray a good layer of High Build primer on your project, and then let it dry. The time for the stuff I'm using is 2 hrs before it can be sanded. A good way to tell if it is cured enough to sand is try poking it with a fingernail, if you leave an indent it isn't ready. Don't start sanding too early or it will make a nasty mess. If you choose to wait longer to sand, no biggie, I've waited a few days because I got distracted with something else. Once it's ready to sand, mist on a guide coat of a contrasting color. This will allow you to see where you have sanded and any low or high spots that still remain.

See Pic 2 for an example.

Hopefully you are able to sand it smooth and all your guide coat disappears, but if it doesn't you can apply some pinhole filler to help even it out. If you have to do a lot of rework you may want to spray another layer of high build and guide coat it again. Remember, proper prep is what will make your paint job into a masterpiece and easier to finish.

Once you have your project sanded smooth it's time to seal it. The primer I'm using can be used as both a high build and a sealer. To seal it I just add reducer in addition to the catalyst. I spray one medium heavy coat and let it flash off or 30 minutes. You'll know its flashed off when the surface goes from shiny to a dull look, this means the reducer solvent has mostly evaporated. At this point you add your base coat. For my project I'm going with a Gunmetal metallic undercoat and a Kobalt Blue Candy over it. I sprayed the Gunmetal, waited a few minutes for it too sort of flash and sprayed another coat, this is as per the manufacturers instruction. I then waited 30 Min's for it to flash off and sprayed my candy coat. The more layers of candy you use, the darker and richer it gets. I did three.

(see pics 3-5 for the different coats)

I then let this flash off for 30 minutes. Between all these different color coats you are cleaning your gun really well, or else you are throwing it away and buying a new one.

After the candy coat has had time to flash off it's time for the clear coat. This it the coat that brings it all together. When I spray it I spray a medium light coat and let it sit for 5 or 10 Min's, just long enough to become kinda stringy. What this means is if I touch it and pull my finger away, stringy looking stuff follows my finger off. You want to do this in an inconspicuous place. Once this happens I'll lay down a medium thick layer, hopefully not heavy enough to sag or run. If you do have small sags or runs, all is not lost, it just means I get to introduce you to my friend the Nib File. I'll show you this next post.

As promised, this thread would entail not only the how too's, but also the mistakes I've made.

The last few days I've been trying to figure out why I'm suddenly getting fish eyes in my clear coats. I've sprayed over a dozen pieces with no problem, but my gas tank and front fender are plagued with them. At first I thought it was due to the fact I hadn't emptied the water traps on the compressors and water separator, so I did that. Still getting fish eyes  After a couple different clear coat, wet sand sessions, I think I've finally figured out what is going on. Up till now I wouldn't really do anything between the base coat clear coat step. Now that I'm painting the show pieces though, I've been really careful of dust and other stuff getting on the surfaces between coats. I started tacking the pieces down with a clean tack cloth between the base coat and clear coat. What I didn't know was that no matter how lightly I tried to do it, the tack cloth was leaving contaminants that was causing fish eyes. At least that is what I currently think it is. I won't know for sure until Wednesday, since I'll wet sand them tomorrow and have to let them off gas overnight. I'll report back what I determine.

Brandon

[stainy]

Thanks for the tips I copied them all for later use !!

[manjisann]

Thanks for the tips I copied them all for later use !!

You're welcome!! Stop back by and let us know how it goes!

Brandon

[manjisann]

Ok, so I removed all the paint from the tank and reworked the filler a bit more. If you get fisheyes you don't automatically have to remove the paint down to the bare metal, you can wet sand it using 800 grit until everything is a uniform dull. Be careful on corners though, and that you don't go through the clear as 800 is fairly aggressive when it comes to clears. If you were wet sanding just to put another coat of clear or do some art work you'd actually want to you 1000 grit. I'll discuss this more in detail when I get there. Right now I'm getting ready to go out and spray the high build on the tank, and start the process all over 

I wanted to copy a post from another thread I had started when I realized it was my tack cloth that was causing the fish eyes. One of our other members is a automotive refinishing tech and was kind enough to drop in and point out what I likely did wrong and the proper way to use a tack cloth.

Heres the link to the actual thread, as there is a little more detail from some of the other posts in it:

http://forums.sohc4.net/index.php?topic=57264.0

Here is the post from Fishhead:

Quote from: manjisann on August 25, 2009, 05:10:04 pm
http://forums.sohc4.net/index.php?topic=57137.0



Quote
You're prolly on the right track vis a vis the tack cloth = fisheyes expecially as someone said if you press hard.

Unless my hand is fatter than I think it is, I was actually pressing really light.

(JMO)You shouldnt be pressing at all. A gentle touch is all that is needed.

 The tack cloth is the final cleaning of the surface to be painted and should have very little dust.etc on it. The other cleaning processes (blowing it off with air, wax/grease remover,etc) should get 99 % of the unwanted stuff off. The tach rag should be gently "wiped" over the surface to get any remaining dust particles off.

   19 yrs as an "automotive refinishing technition" (AKA= painter ) and the only time I have had tack rags cause a problem was when the "automotive refinishing technition assistant" (AKA= prep dweeb ) wiped the car down with too much pressure with the tack rag. Fisheyes out the wazoo. Never had anyone wipe down anything for me again.

  I always open up the tack rag completely (unfold it)  and then lightly bunch it up to give a lighter touch on the surface. Using the tack rags the way they come out of the package (Flat and squished) makes it harder to use a light touch when wiping down a surface.

Thanks Fishhead for the information!!

Brandon

[manjisann]

OK, so quick rundown. I stripped the tank of all the paint trying to do as little damage to the body work as I could. I then touched up the body work and shot the first coat of high build primer. The black is the guidecoat for contrast, sand sand, oh dear more body filler for some areas I missed. At this point I was really wanting just to paint it, but since I touched up a fair amount of body work I sprayed a second coat of filler primer, extra thick. I sanded this one down really well but it filled in the minor stuff that would have popped up in the paint job.

I sprayed the sealer coat and it went on pretty well I felt. There were no runs in it that I can remember, a couple of minor sags. I felt they were minor enough that they would level out in the clear coat. Since I'm spraying candy the sags would show up a little in the candy, but being this was my third time shooting this tank I was fine with it.

I wend to spray my metallic paint and started having issues with the paint not flowing properly in the gun, grrr! It would start out nice and heavy like I wanted it to, but after a few seconds start to peter out. If I put my finger over the tip so it forced air back up the needle and into the cup it would bubble and clear it for a sec. I'd pull the trigger again and after just a second get that nice solid spray I wanted, but again it would peter out a bit. The frustrating this is this was a new gun I had just bought to replace another that wasn't working right  I hobbled along like this so I could get two coats of the metallic on. Once I was done spraying the metallic I cleaned the gun thoroughly again and popped off the knob that adjusts the pattern width to see if any paint had somehow backflushed into the air passages. Nope, looked good. As I was reassembling......*SNAP* I overtightened the nut and snapped the top off of it! @#$%$# I had literally just bought the gun the day before! Long story short, the store I bought it from went above and beyond and just replaced it even though I'm sure I'm among their lowest grossing customers. They now have a customer for life, or until they show they don't know what decent customer service is. I was all set to buy a new one since I was the one who broke it. Great place, National Coating Supply here in Utah.

OK so rewind, I was in a bind so I grabbed the gun I swore I'd only use for clear and shot the candy with it. If it had been any other color than candy I wouldn't have done so, but candy doesn't have much in the way of pigments or solids so I felt sure it would clean out well. I love the spray on this gun, it's by a company called VAPOR, I'd imagine it's NCS's in house brand. Anyhow, it is a beautiful pattern for a $45 gun. I unfortunately got a few runs, again, I felt nothing major and pressed forward. 3 coats of candy for the color I wanted. I let it flash off at this point for the required 30 Min's.

I should point out that I ever so lightly tacked off the metallic coat before I sprayed the candy. I wanted to see if a light touch was what would fix my problem before I gave up on tack cloths all together. It picked up a surprising amount of dry spray, but also left a few fuzzies, which you will see caused a few problems.

Fishhead suggested that between the metallic and candy coat, spraying some urethane clear coat. This will help to even out any sharp bumps produced by the micro flakes in the metallic paint and apparently adds a lot of depth to the effect once you spray your candy. I'll try this on the remaining pieces and report back.

Once the candy coat flashed I sprayed a couple coats of urethane clear and let it cure for 24 hours.

Here's some progression pics just to show this time around.

Brandon

[manjisann]

After it had dried I wetsanded it using 1000 grit. For those who haven't wet sanded before here's the basics.

You buy wet sandpaper that you soak in water. Wrap it around a foam sanding block (I'm using one made by Meguars) and sand with medium pressure. Be sure to frequently wipe off the area with a wet rag and dip your sander in the water bucket. This keeps the sand paper from loading up with gunk.  Be very careful of edges or any high spots as sanding through it depressingly easy (see the pics, it happens). Sand until the surface is a uniform dull, and then you are done.

Before wetsanding be sure to clean the surface with wax/grease remover otherwise you risk forcing it into the sand grooves.

The bottom pic shows the top has been sanded and is dull and the side is still unsanded and shiny.

Brandon

[azuredesign]

Wonderfully instructive tutorial.
Thanks big time!

[manjisann]

Wonderfully instructive tutorial.
Thanks big time!

You're welcome!

Sorry it's so wordy everyone, once I'm all done I'll go back through and see if I can stream line it a bit, but for now just trying to ensure I get all the info in there. Like my bike (and me, I'm sure my wife would say  ) it's a work in progress.

Brandon

[lynchj]

Very nice! Thanks.

[manjisann]

Very nice! Thanks.

You're welcome, hope you find it helpful!

OK class, now that we've had a long break, on to what I did next.

I love the blue that I chose, it's very intense, but I don't like it on it's own. The tank had a graphic that I thought was pretty OK, but I wanted something for the fenders, side covers, trunk and sidebags (as a side note, funding has run short so the side bags and trunk will hopefully be next years project!)

The biggest problem I had with the graphic is how long it took me to tape off. I think it was at least 4 hours of tracing it onto the tank and then taping and frisketing it. Was it worth it, I think so. Would I ever do it again, not on this project, but definitely would like to get better at it! Lets face it, for all the pain in the a$$ painting has been, it's also be very fun and rewarding to see how it turned out. Is it perfect, not by a long shot, but I can honestly say I tried my best and am very happy with the results, and for me that's enough at this point.

Back to the bike. I wanted something that would kinda break up the blue but not be wayy overpowering, or take a ton of time to tape up. I was discussing this conundrum with a coworker and he pointed out "Hey, everything goes faster with a stripe!" After I stopped chuckling I really thought about it. He suggested an off center stripe. At first blush I wasn't super thrilled with the idea, but the more I thought about it the more it grew on me. I decided to go with a simple two color stripe. The beauty of a stripe is it's straight, so it only took about 20 minutes each piece to do. It might have taken less time, but I used a ruler to check it at regular intervals to ensure it wasn't bulging or getting skinny.

The first two pics show the parts taped off for the stripe. I laid down fine line tape first for the stripe. This gives it that nice crisp clean edge. I then taped these non fuzzy paper towels on the areas I didn't want paint. A note here, if I had it to do over again, I'd either cover all of it in the green painters tape, or tape the towels down better as I got a few sparkles on the tank from this. Also, don't flip the towels over after you've taken them off, the sparkles go everywhere and you'll never get them all up 

Before taping this down I had put some frisked paper over the graphic as I needed to do some touching up on the candy coat I had nicked when doing the graphic. I'll touch more on this after I finish explaining the line.

One thing I learned doing the graphic, this plastic fine line tape, and the plastic frisket I bought, don't really like to stick together very well, this was also why I decided to use the green painters tape. The paper tape stuck to the plastic fine line tape pretty well.

After I was done taping it up, using an airbrush (I didn't want to put to heavy a paint layer down, or else when I clear and then wet sand I'll run a greater risk of sanding through the clear and into the stripe,) I laid down a good thin layer of the gunmetal paint. I did two coats to ensure there weren't any light spots, but it should still be thinner than if I sprayed it with a full gun. I let that dry for 30 minutes ( I actually use a kitchen timer as my sense of the passing of time is pretty poor, especially when I'm paying attention to it!)

After 30 minutes it had flashed off, I did a quick tack off with the tack rag, being VERY careful to not put any pressure on it so as not to get fisheyes! I then took my 1/8 inch fine line tape and carefully lined it up on either edge.  I then sprayed a couple thin but covering layers of black. I allowed this to flash for only 15 minutes and then I removed all the tape. If you let paint dry for too long before removing the tape you run the risk of pulling up the paint as well. If you don't wait long enough you can also goof it up. When removing the tape, pull it sharply back on itself and you will run into much less problems with the paint trying to come up with it.

Once the tape was all pulled off of both pieces, I used a brown 3m scuff pad to carefully scuff off any stay sparkles I could see from the metallic paint.

I then cut the frisket that I already laid over the graphic to expose the spots that needed to be touched up. I am still a complete novice when it comes to painting, and doubly so with an airbrush. After a bit I found that if I turned the paint knob down so only a small amount of paint came out, I could very carefully build up the candy and feather it out a bit. Unfortunately before I discovered this, I had already created a line where the frisket was covering the graphic to keep it from getting the candy on it. It's only noticeable if you look directly at it and is better than the shiny silver gouges that were there before. But if I had known about turning the brush down to slowly build it up, I may have be able to keep that well defined edge from forming. Oh well, you live and learn.

I then very very carefully wiped down the areas I hadn't sprayed with wax/grease remover. I mainly did this to help remove any of the scuff dust that was still on it. I let it flash for another 30 minutes to be sure everything was properly cured and then sprayed my clear coat.

I've decided at least with what I am spraying now that unless I am doing a final clear, I won't worry about adding the flow enhancer. All this does is helps to thin it out just a bit and make it flow more (hence the name  ) But since I'm trying to build up the clear coat layers and I'll just be wetsanding between clear coats anyway, I'd rather not add the Flow Enhancer and build the clear up a little faster. This is just my conclusion, everyone must decide for themselves based on what they are trying to accomplish, and what paint system they are using.

The next couple pics are ones shortly before I cleared. You can see some of the scuff marks and also the clear frisket over the graphic.

Also, before clearing and after wiping it down with the grease/wax remove, I gently tacked the tank and fender off. This actually removed a lot of the metallic looking overspray and some of the scuffing dust. Again, I just caution you, be so gentle on the pressure when using the tack cloth that if it was on a sensitive scale, it would register no weight change. Other wise you risk fisheyes, and there are few feelings more frustrating that seeing fisheyes looking back at you from an otherwise beautiful clear coat spray!

The last pic shows the tank after clear coating. I think the line really really compliments the piece and on the fender (not pictured, sorry) It's very striking. All in all I really like how the line turned out.

Brandon

[manjisann]

Ok, so a bit of an update. I found out the hard way that you aren't supposed to tack between clear coats    It made an absolutely awesome mess like I had never seen. At first I thought it was cracking, but in retrospect and after talking with the paints manufacturer, I think it was fuzzies left behind by the tack cloth.

What you say, tack cloths are supposed to pick up fuzzies not leave them?? Normally that would be absolutely correct, and on any other coat it would be so. However, at least with the Urethane clear I am using, the pot life is 5 hrs, that means it takes a lot longer to set up than any of the other coats. It may be "Dust Free" after 30 mins, but if you even ever so lightly tack it, you'll imbed fuzzies, and it's not pretty.

To fix this I will be wetsanding off the last layer of clear. The biggest dissapointment is of all the stuff I've sprayed, this was one of the best in terms of no runs or sags. Oh well, this is how you learn. Here's some pics, unfortunately the overall effect doesn't photograph well. Both pics are the same part I promise.

Brandon

[masonryman]

I don't think that is from the tack cloth, there is a problem with the set time or volume applied you need a faster reducer, more catalyst, or something. I would defiantly get some fisheye eliminator and some accelerator

Mark

[masonryman]

Looking at pic 1294 the clear looks like the viscocity is heavy are you thinning it, how much, with what

[lockpn]

Interesting read so far.  Let me ask some questions and add comments for thought.  No particular order.

1. Are you truly using a basecoat/clearcoat system or just clearing over what could be used as a topcoat?  Thought is if you are using a catylized base coat it may be setting up before the clear is applied.  This is related to #2.

2. Have you considered temperature in the pot-life time.  As temps go up pot-life decreases, which means paint consistency goes up quicker.  I'm in FL and believe temps here are close to what you have, humidity is of course totally different.  You can get two good coats on but if they start to set-up they will interact with the third coat and cause an alligator effect. (which is what I believe you have, not fisheyes).  I try to get my clear coat done within 20-30 min from when I mix the paint.  Of course, to quick and solvent pop is an issue. (no one said this is easy)

3.  You souldn't use a tack cloth (personal opinion).  If dust is a problem maybe you have a static issue.  Talk to a local painter to see how they deal with this.  One way to help may be to use a water based wax/degreaser rather than a solvent based one.

4. Last thing, you mention wiping paint dust with the tack cloth.  My thoughts are, they shouldn't be any paint dust.  Re-reading I noticed you use a touch-up gun with a 1.0 nozzle.  These guns are just that, touch-up.  They atomize the paint finer with less paint flow and designed for painting small areas.  Adjusting the pattern for painting a tank would be difficult and is probably causing the premature drying of the paint, especially at the outer edges of the fan.  Also try experimenting by reducing the air pressure.  I recommend a 1.4 gun for topcoat.  This may solve may problems.

Hope there is some useful info for you here or at least some things to think about.  Keep trying, you'll get it.

Paul

[masonryman]

Lockpn

I mentioned the fisheye producted (we use Rubber seal) because of it's flow characteristics and the accelerator so maybe it would not cause the clear to kick. thoughts?  what about build up and consistency (thickness)?

[lockpn]

I don't used fisheye eliminator products.  As was mentioned elsewhere it is just a bandaid solution and I don't how it will react to different paints.  You should find the root cause of the fisheyes and correct it.

Things I do:
1. Use a good wax remover/degreaser between stages
2. Use it before initial sanding so you don't sand silicones into the paint
3. Seal the bare metal or old paint with epoxy primer
4. Eliminate oil and moisture in air line

I use a HVLP turbine system for color and clears, so oil and moisture are not a problem.  I use a compressed air HVLP gun for high build primers (1.8 mm) and when I have a problem it's usually because of poor surface prep (in a hurry and cutting corners).  Haven't seen problems with flow following manufacturers specs.

I think adding an accelerator will make the clear to kick faster.  This would be for colder climates, which is not the situation here.  To slow down the reaction you could cool the mixture (not very practical).

Hard to judge buildup and consistency from photos.  Three or four good coats with a 1.4 mm tip is perfered especially since these parts will be sanded and buffed.

Brandon:
For reference, how long does it take to lay down one coat on the tank?  I'm trying to time it mentally and think I take about 15 secs.

Paul

[manjisann]

I think I mentioned earlier in this thread that fisheye eliminators contain a large amount of silicone. The way they work (or so I understand) is you so contaminate the paint that it has no choice but to bond with whatever is causing the fisheyes. The biggest problem with this IMO is you have then contaminated your booth and spray equipment and so you will have to continue using the product or else decontaminate your equipment. This wasn't something I'm willing to do at this point, and I ended up tracing the fisheye problem to me pressing down too hard on the tack cloth and getting the tack substance on the paint. Once I stopped being so heavy handed the problem went away.

Please forgive my poor photography skills, they don't show the current problem well and as you can see, make it look like something else. I haven't wetsanded the paint yet to prove what it is (I'm a bit burned out on painting, so I'm going to try and reassemble the bike a bit this week) but I honestly am thinking the rep from the paint distributor was right and I ended up getting fuzzies in my clear from the tack cloth. Once he said that I looked at the problem and it does look like a ton of fuzzies just fell in there (again, my pics aren't good enough to show this, you'd have to see the part.) I'll be sure to post what I discover.

Lockpn, 15 sec or so sounds about right for a single coat to be sprayed on the tank. Too much slower and it gets to thick or heavy and runs or sags. I'm using a 1.0mm touchup gun since the pattern is smaller and the overspray isn't as bad. This is just a personal preference.

Thanks guys for your thoughts and brainstorms!

Brandon

[masonryman]

manjisann

From rubber seal
RS-2501 is Silicone Free. Will not contaminate paint guns or paint gun washers.
http://www.rubber-seal.com/prodview.asp?prodID=1457 

I work in a very low volume restoration shop, we paint parts all the time, but doing total restorations in a 2 man shop we only do an all over paint job (Whole car) at the rate of 8-10 a year so we some times paint in less than perfect conditions. I don't want to come off as a know it all, because I don't. We are offten told that what we do should'nt work,  but we do OK

Good luck

Mark

[manjisann]

I work in a very low volume restoration shop, we paint parts all the time, but doing total restorations in a 2 man shop we only do an all over paint job (Whole car) at the rate of 8-10 a year so we some times paint in less than perfect conditions. I don't want to come off as a know it all, because I don't. We are offten told that what we do should'nt work,  but we do OK

Good luck

Mark

Mark, if I said something that made you think I thought you were saying you knew it all, then I apologize, as that isn't the case. I read what you were kind enough to share as your experience and opinion as someone who has painted, and I greatly appreciate you taking the time to stop by and post! Unfortunately the camera I'm using and my own skills aren't the greatest and the pics I posted of the side covers don't show the real issue very well. The problem is bumpy and hard, so I know it's not fisheyes, and what I initially thought was cracking or crazing I don't think is the correct diagnosis either. If there was just one of the little bumps I wouldnt' have given it a second thought and would have just hit it with a nib file, wet sanded and gone on. But it was the large volume of crud that threw me and made me suspect something other than dust. After talking to the paint rep where I bought the paint through and going over my process and him pointing out that it may have been dust or fuzzies from the tack cloth, it all made sense. The paint is on there solidly so it didn't seem like an adhesion problem, so that ruled out a lot of stuff. I really won't know for absolute sure until I wet sand it, but that won't be for another week or so as I'm a bit burned out on painting and have to wait for more clear coat and reducer to come in, so I've decided to piece the bike back together this week.

From rubber seal
RS-2501 is Silicone Free. Will not contaminate paint guns or paint gun washers.
http://www.rubber-seal.com/prodview.asp?prodID=1457 

Ok, I have no problems admitting when I'm wrong, and I definately don't want anyone to get the impression that I think I know it all. If I'm wrong, feel free to point it out as MasonryMan has. I did a quick google search of fisheye eliminators and found that many of them have silicone oil or silicone based products in them, including the one from the Kustom Shop line. I'm not saying NEVER use this stuff, I just think you need to know what you are using before you use it. If you use the silicone based Fisheye Eliminator, it is my understanding that your booth and equipment become contaminated and you have to do a thorough clean up. I really would rather track down what was causing the issue and determine at that point if I wanted to use the eliminator. Since it turned out to be more of a process issue on my part and not an uncontrolable environmental element, I chose to fix what I was doing wrong. Now if you have no choice but to spray in a less than ideal environment and you are always getting fisheyes, then make the choice based on that.

MasonryMan, have you had any issues with delamination of the layers using this product? I've read (again, showing my lack of experience here  ) that fisheye reducers can have bonding issues. 

My goal with this thread is to create an informative jumping off point for anyone who is thinking of trying Urethane based paints (and really just painting in general, as many of the prep tips and other stuff still applies.) When I first started, I could find a lot of info on using this stuff but it all said "For Professional Use Only" and would assume you already knew what you were doing. I had no idea what Flash Off meant, or any of that stuff, so I'm just trying to in a way make a Urethane Painting for Dummies type thing, without insinuating we're dumb. I think that this stuff can be safely used by the home hobbiest as long as certain precautions are taken.

I know many pro painters and who knows maybe even the firemarshal would flame me for doing this in the garage of a home, but I feel that I have taken every reasonable precaution to ensure my safety and the safety of my family. The exhaust of my paint booth is only inches from the garage door, so when it is on, it exhausts outside the garage. Any trace of paint fumes that I get in the garage is largely due to when I unzip the door to exit and is quickly gone. I don't store the open paint containers in the house, since where I would store them is fairly close to the furnace. In my mind this is an unreasonable fire hazard, so I leave them in the garage. This also has the added advantage that they will be the same temp as outside. The biggest issue with this is when it becomes winter and freezes the paint will be ruined, but I was planning on tossing it anyhow. I've been very happy with this line of paint, but the inconvenience of having to order it online and wait a few days while it arrives offsets that. Next year when I paint, I'm going to go to the NCS store and buy the paint from them. My suggestion, support your local paint stores as long as they give you good service, and this store IMO has given me 110% service, so they've earned my meager business. ok, err soap box going back in it's hidey spot.

Seriously though, MasonryMan and everyone else, please feel free to post your experience or questions here. And if I come off like I'm sounding like I know it all, or as if I'm implying you're sounding that way, either call me on it and I'll try and reword it, or just know it's never meant that way. The biggest thing I love about this forum is the exchange of information and ideas, and I don't want to stifle that on this thread.

Brandon

[blake255]

Wow.  This is one great thread.  Keep up the good work Brandon.  Perseverance!

Blake

[masonryman]

I think your doing fine, the only de-lamination issues we have had in a very long time was on some bright silver, which always seems to have issues.

We use the rubber seal fish eye eliminator more for the flow characteristics than anything urethane is usually very tolerant and you usually done get fisheyes you are more prone to get a kick, raising of the basecoat or first coat of clear.

 

Mark