Ben Hart
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Base can be thinned more, but really shouldn’t need too much. If you thin it too much the colour becomes too transparent and the viscosity changes too much. If you do thin it you must apply it in lighter coats or you will run it
The clear can be thinned more. This isn’t all that uncommon with some clears. As a general rule though, you do not want to thin it more than 10% beyond what is called for.
Thinning a product allows you apply it in thinner coats. Thinner coats tend to dry faster, however I wouldn’t change the flash time solely based on this.
Flash time is minimum. Tech sheets usually have a max recoat time. That is basically the maximum flash time. If you go beyond this, in most cases, you will need to sand/scuff what you sprayed and reapply. Typically I go by the flash time since I am spraying in a heated booth with good airflow. In cooler temperatures and/or less air flow you NEED to increase the flash time. Judgement/experience is what generally dictates how long to allow something to flash.
Welcome to the site.
I have used ChromaBase in the past, it is a decent system. As for your questions, the panel to be painted needs to be prepped before basecoat (in this case, basecoat being ground coats and mid coats). Chromabase seems to hide scratches a little better than some other products and may even be able to cover as coarse as 400 grit dry. In any case, I would want the panel finished with 500-600 dry (on a DA) or about 600-800 wet. The tech sheet will read something similar.
As for application, apply your gound coats with adequate flash time between coats. Allow the ground coat to flash about 15-20 before proceeding to midcoats…DO NOT sand or scuff the ground coat. Apply your midcoats with adequate flash between coats. Allow a longer than normal flash before clearing, again, DO NOT sand or scuff the midcoat. As for flash before clear it depends on the number of coats, airflow temp etc. When I used Chroma base I usually waited about 45-60 minutes before clear just to be safe.
I recently saw a Cadillac I did tri-stage white with Chromabase about 3 1/2 years ago, still looks good and is holding up well.
On another note, did you read anything about let down panels for matching tri-stage colours?
[quote=”DailyDrivenMini” post=26573]That was the feeling that I was getting. LOL
Some wasted paint but I learned something. Other than excessive paint, why did that happen? I did not have any run on the base coat.
I do have 2 moisture filters in the line, may be that was not enough? Too thick of paint trapping air?
As you can see the hood is on the car now.
I got a few other panels to paint, I will re-paint when I am painting that.
I still want to learn why it happened though.
Thanks.[/quote]
Your hood has quite a bit of orange peel (texture) an the large sag/run. When the paint is really thick (like in the run) the top layer can dry quicker (skin over) before the inner parts can flash off solvent and dry. This traps the solvent in there. The bubbles you see are from that, and called solvent pop.
Your hood also needs to be sanded a bit more before painting. There are still some shiny areas and some texture left in it.
As mentioned, paint it in a flat position (as it would be on the car). Your basecoat doesn’t need to be applied as heavy/wet as the clear. If you can apply the clear in thin wet coats, with even overlap (when passing with the paint gun) you will get better results. Also, it is a good idea to have some masking paper, or anything you can spray on to setup your gun before you start spraying. This way you can see how the product is spraying & laying down before you move onto your panel.
Keep it up, you will learn from your mistakes are get better.
So, just to clarify, the first coat of epoxy that was done 1 year before everything else came up as well?
How old were the products when you used them, particularly the activator? Was there ever any humidity issues, or water in the air line?
I’ve used that stuff before (sorta like their cheaper polyurethane, very similar to Endura, but crappier). It is an epoxy, but much thicker than traditional automotive epoxies. It has some filling and sanding ability, but no replacement for 2k urethane. I believe its filling abilities are more intended for sandblast profile and minor metal work imperfection on industrial parts.
Personally I wouldn’t have even considered using this on an automotive application 🙁
In any case, I would grind it off, back to bare metal anywhere you want to fill. Not the same type of automotive epoxy you can fill directly over.
Prep the booth with whatever grit it takes (sand scratches showing aren’t an issue). Basically feathered out the nasty spots and used the grinder in a few areas. I didn’t have a lot of dis-coloured areas after sanding and not a whole lot of bare steel, so I just spot primed with aerosol primer, then 2 coats of colour. Takes no time at all to spray.
Yeah, booth coating is that clear film you hose off…
I just painted our booth, I used U-Tech 3.5 Polyurethane. In other shops we have used similar products.
I would think any decent 2k single stage paint would be great. Use whatever you have available on the bare metal. I assume you will apply booth coating after the paint cures, so it really doesn’t matter what it looks like, as long as its clean, white and durable.
You really can’t go wrong with either of the Sata’s. And although the 3000 is faster than the 4000, unless you have enough of a feel for painting, you may not notice a huge difference.
The video shows the method, however, what I do is put a piece of 3/4″ tape on both ends of the razor blade so I am just filing with the centre section. This prevents causing damage from the sharp corners of the blade. I also go further with the razor then the guy with the video, and minimize sanding. Sanding, even with a coarser grit and hard block will not get it as straight as the razor will.
It is tricky and dangerous, so be very cautious. Also, be prepared to possibly have to respray it, just in case…
Looks great. I’m having a cement parking pad poured beside my garage in the coming weeks…now I’m just embarrassed to admit how much it costs. Looks like you got a killer deal there!
Well, I’ve used the 3000RP & HVLP and 4000RP a fair bit, both great guns. The 3000RP is the faster of the 2, however, I prefer the 4000. I’ve only used the Iwata once. It seemed nice and sprayed well, but just didn’t feel “right” to me.
What are you looking to use it for? Just as a clear gun?
Overnight is usually best.
For minor defects in clear, stating with 1500 and finishing with 2000-3000 is typical.
If you are getting a run out it is usually easier (and will make it flatter) to use something else first. I usually use a new razor blade (with tape on the edges) to file it down. Then proceed to blocking with 1500, then 2000, then a little 3000 before cut polishing.
If the run is really bad, it is generally quicker to flatten it down then re-sand the entire panel and reclear it.
Don’t worry about it. There is a steep learning curve to painting. No one gets perfect results the first time…it takes years to get good, and even professionals get runs now and then
Is this in the basecoat or clear coat?
If it is in the base, you can let the base dry for a while (probably at least 1/2 hour) and gently wet sand out with 800-1000 grit, you will need to rebase after. If the runs are bad, you may not be able to fix them easily this way.
If you ran the clear, minor issues can be sanded out and polished after it is dry (next day). If there are major issues you are better off to let it dry a day or two and start over.
Post some pics if you can
Looks great!
Now you need a ramp and a door to convert to a pull through booth! 🙂