It’s always awkward joining a new community and being new. I go to several forums and get answers to certain topics. Most notably, cadillacforums.com There, I’m not the new guy, and I feel more comfy. Lol! That being said, here we go....

So, I recently decided to get into painting cars as a hobby. Bought a big air compressor,spray gun, and all the other things needed to get the job done. Da-um! This is an expensive hobby. But for as long as I remember, I’ve been fascinated with wanting to learn auto paint and body. My high school best bud ended up(and was always able to paint) opening up a very successful paint and body shop in the Dallas Ft Worth area. Although I don’t speak to him much anymore, I was around his shop a few times back in the day(I’m 51 now). So I do have a little knowledge of the trade. So far, getting all this new stuff, it’s been a lot of fun. I wasn’t planning on getting my first project the way I did, but it came sooner than expected. I accidentally hit a mail box about a month ago and damaged my hood of my truck. I went to the junkyard, excuse me, salvage yard, and bought a hood to replace my damaged one. It had the OEM paint on it so I didn’t think I’d have to do much work but sand and paint. Turns out, after getting it home, it had a few dings and one big ding on the top that needed body filler. So off to the races to learn auto, paint, and body! I have a lot of questions, but I’ll stick to the one that I came here for, and maybe others later.
Since I ended up doing a lot of body work on the hood, I ended up 2K priming the whole hood. But I thought I may have mixed the wrong stuff with the primer. I keep hearing “which reducer did you mix your primer with” like in this thread

viewtopic.php?f=5&t=27339

I didn’t mix no reducer with my 2K primer. I mixed activator. I thought that’s what the guy at the paint store told me to do. I do know a little about activator being a hardener and all, and the reducer thins primer and paint(I think). My question is:

Can someone explain when the activator and reducer is used? For the paint? For the primer? And sometimes I believe both are used? I’m a little confused

Thanks, and very glad I found this community! I’ve found and learned a whole lot so far

Kenny
Ft Worth, Texas

I think I know a little

You're okay....not really even that confused. Here's the deal....Anything that is a 2K (means 2 components) means that some type of catalyst/hardener/activator is used to start the chemical reaction needed to cross link the material on a molecular level and poof! harden. Notice how I slid all those terms together....That's because the slang has started to be thrown around quite loosely like this. Now, reducers....This is a word I really had to get used to when it came on the scene almost 40 years ago. Back in the old days we did indeed have thinners to use with old lacquers. Thinners made thick stuff easier to shoot and could be different temp.s for different conditions. When these newer cross linked coatings came along you couldn't just use a simple thinner with them....instead they required viscosity adjustment by using "reducers". ALL 2K style coatings will usually require an activator and some guys will also activate their base in a base/clear system. Now the reducers, depends on your gun, gun settings, etc., may or may not be needed with your set-up. You can indeed live without reducers but you will definitely NEED those catalyst/hardener/activators for the coating to harden/cure correctly...... An example of some reducer being needed would be me....I shoot with turbine (think warm air at low pressure and high cfm) systems so a multi-stage turbine can actually make enough heat to prematurely evaporate some of the solvent in my mix. By simply adding some matching reducer I can balance that mix back out for proper flash/dry/cure......
So does any of that help?????

To put it simply:

Activators: activate the curing cycle. They come in different speeds: slow, medium, fast for use in different temperatures. Personally I use slow activator all the time.

Reducers: reduce (old term was thin) the activated products. These also come in different speeds: Fast, Medium, Slow and Extra Slow for use in different temperatures.

When it is hot, like it gets here in Arizona, using a slow activator and a slow reducer allows more time for the paint to lay down.

Yes Darrell, a lot of it helps. Thank you!
My spray gun is the Devilbiss Finishline 4 FLG-670 And plan on shootin Nason Ful Base “IF” paint and Nason Select Clear 497-00. I believe the paint store guy told me to mix it 4:1. He gave me some reducer but told me I may mix it 4:1:1. But honestly, I can’t remember why. I’m concerned that the Texas weather is going to effect my spraying, and I’m trying to wait until it warms up. It’s for some odd reason 20 degrees below our normal average the past week(I’m trying to be patient).
Any more advice with my scenario? Should I wait til it warms above 70? And any thing on my mixing ratios?
Btw, I just mixed my primer(5Star Extreme) 4:1 w/activator. It was my first shoot and turned out fairly well, but was thin in some places. I definitely made some mistakes that I plan on correcting for the bc/cc. Like, more room to shoot, and ,definitely more light! But over all, the primer is going to work.
Thanks again
Kenny

Yes, and 68 is right about the temp.s on all of this.... I was waiting for you to "digest"all of the other stuff before moving on to the temperature thing with all of these products. Since you are in Texas (once you come into your warmer temps.) you will be shooting a lot like him and preferring to use the "slow" versions of most of the activators and reducers. If you are running into cool temp.s at this point you have to watch metal temps. and room temp.s not getting so cool that the chemistry can't properly flow out and cross link. Your patience will be rewarded if you can wait on some moderating temp.s. I really don't like any working environment for coatings to drop lower than 65 F. I know there are some guys that work stuff colder but that's too much like hard work for me...... Oh, and about mix ratios....get P. or Product Sheets on every coating you use. They will tell you exactly how to mix and adjust your mixes.

Kenny
Every thing said so far is the God honest truth PLUS some good advice.
I too like Cold OR SLOW activators AND Reducers.

Do you understand how a Paint Mixing cup works?
How and what all the different Scales are for and how to use them to mix your Paint correctly? When I first started I didn't know how to use one correctly.

Ok copy on the temps. I will definitely be patient. I don’t expect my first shoot to be perfect, but since I am a little OCD, I tend to want to do things exactly right when possible. Next Sunday it’s supposed to be in the mid 70’s. I know you said that about the metal temp, would mid 70’s outside temps be good? Today I finished up all my sanding and have it ready to go when the time is right. So I am super excited to paint this hood. And the hood is as smooth as a baby’s bottom everywhere(400 grit).
Real quick, I did run into one issue where I put some body filler, and maybe y’all could help me out and make sure I did this right. After priming, I started my sanding with 220 or 320( I can’t remember to be honest) I noticed where I laid some body filler I could see the outline of the filler(an area of about 5x5 inches). I couldn’t believe it bc I thought I did everything right. It was too obvious, but I could see it. I was out of activator and couldn’t mix up anymore 2K primer. But honestly, I didn’t really wanna get all that out again anyway. Boy was that a mess! I had made 2 mistakes on my priming day. 1 was I didn’t have enough light where I was. Corrrected that problem since then for my next shoot and 2. I didn’t give myself enough space with my plastic tarps,or curtains. So spraying was vert tight in my little area. That too will be corrected next time. So I’’m guessing maybe I didn’t get enough primer on the body filler spot. But that’s only a guess. So what I did was I sprayed some SEM primer filler on that spot and sanded it again. Now, today, like I said earlier, that spot is nowhere in sight. My concern is, what if I’m all wrong with what I did and after I spray the bc/cc that spot comes through and I’m able to see it?

Doright, I do know how to read the measuring cups. They gave me the mixing cup and told me to mix it 4:1. So I went to the 4 column and filled the primer up to the 4, then the activator up to the next 4. Correct? Had I added a reducer, I’d have gone to the next 4(but I didn’t add reducer)
Appreciate everything guys!
Kenny

Explain your painting technique to us.
How do you set up your gun?
Distance from the panel?
Speed of travel?
Overlap?

The reason I ask is that if the above are correct you shouldn't have any thin spots.

when ever you buy paint or most paint products you can get a product information sheet, not an ASDS but a product info sheet. it will give you a lot of information about your particular product, like temp ranges, mix ratios, application suggestions and a lot more its a must have.
Jay D.

You will not be able to see were your filler is once primed but it will show thru in the paint unless you use a guide coat and block sand.