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Reducing basecoat

I find my HOK basecoat doesn't want to flow out evenly and smoothly. It tends to look a bit blotchy and when dry doesn't give a uniform flat sheen. It looks ok once its cleared, but I'd really like it to be more uniform before clearing. I'm wondering about using a bit more reducer than recommended. Would that help do you think? Would it compromise the base? I use a slow reducer currently and usually spray around 65 to 70 degrees. I'm using an Iwata LPH 400 with the purple cap, 1.4 needle. Thanks, Bill


Trying to be the best me, I can be
Some basecoats will look that way. I've noticed it especially with non activated basecoats. Not really an issue as it doesn't affect how it looks after it is cleared. Yes you can over reduce some basecoats, (mainly non activated ones) but that wont' help you in this case. If it's blotchy like tiger striping then you need to adjust how you are spraying it. Go for lighter coats. Less material more coats, or speed up when you are applying it. Some (most?) basecoats you need to go relatively fast as you are spraying.
This might come of dumb or rude, but if it looks great once it's cleared, why mess with it? But if the blotches can still be seen if you know to look for them, you might have a problem. I for one would look at the gun, though my Iwata is great for clear, it was never too great for base, even with the purple cap. If that's not an option, fine tune the gun by spraying some horizontal patterns on some masking paper. The purple cap has a big fan, it likes low pressure and fairly close spray distances on general, and doesn't like to be anywhere but precisely 90° from the panel.
There's no sign of the blotchiness after it's cleared, but I'm getting more orange peel/texture than I'd like, and wondering if some of that relates to the finish of the basecoat. I'm using 20-22 psi at the gun for base and 24-25 for the clear. I take no offense at any constructive hints or criticism. Thanks for offering your opinions.


Trying to be the best me, I can be
You shouldn't be getting any orange peel or texture in your basecoat. If you are you may be laying it on to heavy. If you reduced it according to the TDS and are getting too much texture you're probably applying to heavy. You may need to speed up on your passes. Less material, faster passes, more overlap.
wow, they're recommending 6-10 lbs! I'll try a sample and see how that works. Do they have a manual like that for the silver cap for spraying clear?
Of the paint that I've sprayed, I find that deltron, HOK, matrix, and diamont spray dry/textured no matter what I do. Ive used different guns, tip sizes, air pressures, distances, pass speeds, slowest reducers, catalyzing etc. It's looks ok after clearing but looks like doo doo before.

However, sikkens,wanda and debeer lay down very wet and smooth by nature and the clear looks better because of it.

I thought for a while it was because of mixing ratio but matrix and deltron are 1:1 and they still spray horrible. Wanda and diamont are 2:1. Wanda sprays very smooth but diamont has a bit of texture.

It just comes down to manufacturer design. That's just my experience. I'm always open to someone correcting me.
wow, they're recommending 6-10 lbs! I'll try a sample and see how that works. Do they have a manual like that for the silver cap for spraying clear?
I only see this for the "silver cap" which is just a stock LPH 400 cap:


I don't think I ever used the purple cap below 10psi, if I remember right it seemed like 14 psi was what worked for me, but I would not testify to it.
Thanks for that. I'll try a couple samples on both caps and see what works best. I hadn't considered going that low on pressure, but maybe that will help.


Trying to be the best me, I can be
The polyester basecoats seem to spray better than the others. I've sprayed a lot of Deltron DBC and I know what you are saying. Activating it helps a lot as does using the best reducer you can get. I notice a difference when I use SPI reducer versus PPG DT. SPI reducer really helps DBC lay down much slicker than PPG's DT reducer.
Tried spraying at 12lbs this weekend and it turned out perfect, nice even sheen, smoothed out perfectly. Sprayed about 4 to 6 inches from the surface. Thanks for the tips.
Nice to hear a success story, sometimes getting metallics right is just a real pain. Even the best paint lines seem to have some that are a real challenge to control even if things are just right.