A few questions about waterborne basecoats.
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Hey everyone.
I’m a hobbyist living in Canada so I’ll have to use waterborne around July.
I do not have a paint booth, I work in an auto repair garage and paint during weekends. I did not have problems with too many dust nibs or trash *knock on wood* and the R-M BC I use is really user friendly, If I get mottles or nibs I can just sand and spray again.
Anyways here are my questions:
1) I’ve used my Sata HVLP with solvent based BC, how do I clean it to use it with waterborne? Acetone? Rubbing alcohol?
2) I lubricate my guns after cleaning them using devlbiss lubricant, is it compatible with waterbrne? I apply it on threads, and needle.
3) Before spraying, can I wipe down the surface with same cleaner that is used for solvent based paints? (sem solve, sikkens M600 etc)
4) If you need to blend, how to do it? Just wrist your gun like you do when spraying solvent?
5)I’ll be using a hair dryer for my first job, see how it turn out. What do you think? :blush:
Thanks in advance! :blush:
1. Depends on the brand your using. Dupont cleaned well with warm water then an Acetone flush. Sikkens does well with a 10 to 1 water to Acetone mix. Just put it in one of the pump bottles used for degreasing and flush your gun with it while holding the trigger and air going through the gun. Just like spraying paint. Always follow with an Acetone flush. Maybe some other water users can give their cleaning methods.
2. That’s fine. I prefer the Iwata lube. It’s just mineral oil and cheap.
3.Yes. Be sure to always use a waterborne cleaner and a solventborne cleaner before paint.
4. Again depends on the brand, but generally don’t flick your wrist. Just pull back.
5. Buy a cheap box fan for larger jobs. Hair drier will work good for smaller stuff. Just remember not to hot, it needs airflow more than heat. Some waters don’t like alot of heat.
Well Ryan’s covered everything extremely well, but I’ll add my bit too if you don’t mind 🙂
1) If it’s clean, it’s clean, so won’t need any major work to convert over to water borne. I use an aqueous detergent solution in my gunwash machine for most of my cleaning, then finish off with DeBeer WB gun cleaner, which I believe is some kind of water/alcohol mix.
2) Exactly like Ryan, I’ve used the Devilbiss lube and it works fine, but I generally use a clear mineral oil.
3) We use a solvent based cleaner during prep (DeBeer silicon remover), then a water based cleaner for a final wipe down in the booth just before spraying. It’s really important that you used both types, as each will remove it’s own set of contaminants
4) I’ve found blending quite different with the various types of WB I’ve used. Once you get the hang of it I think it’s easier than solvent, but I don’t really flick at the edge. Have a look on YouTube for “shopsmart debeer fade out”, which shows you the method used with my particular brand.
5) A good flow of warm air is much better than just heat, so a hairdryer should do the trick, although it’ll be slow on larger jobs.
Lots of air flow and flash time you will be fine…..dont load it up or it will never dry…
Rather then start a new thread I’ll add a few questions to this one in regards to waterborne:
1) Can my painter use his devilbiss GTI to spray waterborne
2) Would the PPS (or another) mixing system be the best way to go, I know he will fight using it to the death… thoughts?
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:hij: :hij: :hij: [/center]You have to get the correct pps cups for water, has a different screen in it. We use the RPS cups from Sata, they work really nice. I would get a new gun dedicated to water, probably a Sata 3000 1.4. Good luck with RM water, we found it to be a huge disappointment coming from Diamont.
You don’t have to use PPS, you can use a plastic cup.
Might want to call Devilbiss, I don’t think the regular GTI is setup to handle water. They make a GTIW that is blue. Might be a different material used internally.
Jimmo – I’d never go back from using the PPS system, but as said you don’t have to use it (or any other similar system) if you don’t want to. And again as said, the finer screens/filters are recommended (I use 125 micron ones). I won’t get too techie about it, but water base can have a hell of a lot of lumps in it.
A standard GTI [b]gun[/b] will be fine for WB, but what you don’t want to do is keep switching that gun between water and solvent all the time. One for each is the way to go.
The set up of that gun is quite product dependant though. Many manufacturers recommend the #115 air cap for water base, which comes as standard on the GTI-W. The only other difference with the GTI-W is it’s colour. It’s a lighter blue so you can tell it apart from your solvent guns. Some brands favour the #110 Trans tech cap (assuming you guys get the same caps as us in the UK), so it’s best to check with your particular paint company, or try them out yourself.
Thanks guys,
Andy I ended up calling the Devilbiss customer support and they told me that the GTI isn’t made with the same high quality stainless steel parts and won’t last long if we use it for water. He suggested when done to rinse it with water and the solvent after…I don’t know exact what would happen, he also said the GTI-W is discontinued…only really the tekna gun for water now. I’ve got one of them on order now anyhow so not to worry (it’s not costing us), i’m not sure if they are just trying to get you to buy a new gun or what…..how goods your source on the info out of curiousity Andy?
Thanks for reply guys. :cheer:
Lots of great info. Good thing I got the Sata 3000 HVLP. Since I have the 1.3 tip I will try either sikkens or Glasurit.
Probably sikkens since I hear lots of raves about it. It better be compatible with Nason 465 clear! 👿 (I almost have a gallon left)Aw crap I just realized Sikkens asks for 1.4-1.5 for their waterborne. :S
[b]jimmo wrote:[/b]
[quote].how goods your source on the info out of curiousity Andy?[/quote]
No source as such Jimmo, and if I’m wrong I apologise, but I’ve interchanged parts between the GTI and the GTI-W with no issues, and I’ve never had any problems using the non -W gun with water borne (nor have any of the painters I’ve ever worked with). Maybe some of the internal valve parts are made of a different material, but normally these wouldn’t be exposed to water anyway.I’d always recommended thoroughly drying out any gun once it’s been cleaned with water though. I’ve been a bit lax in that department with my W400WBX, and even though all Iwata’s are supposed to be fully WB compatible, it has suffered some corrosion and pitting internally, and the fluid nozzle adjustment screw is just about shot.
So as I say – no source or any way of backing up what I said, but I’ve never heard of anyone having any problems after using a regular GTI with water borne base.
Some questions for Sikkens Autowave users. :blush:
1) I just got 1/2 quart of BMW 309 silver. Whats the mix ratio? Guy told me its
10:1 (10 parts BC to 1 parts actovator WB)But I see the Sikkens TDS varies from 10-50 parts. I’m lost.
2)Whats the shelf life of autowave if its not mixed with actiwator WB?
3)Whats the pot life once mixed with activator wb?
4)does activator WB go bad after a while once it has been opened (like clearcoat activator?)
Reduction depends on the humidity,under 40%rh I reduce metallic and pearl colors 30%,if it is hot and dry you can use 50%,solid colors I reduce 10%.
Shelf life is as follows,metallic and pearls one week,solid colors 3 months,metallics and pearls with MM777 are only good for 24hrs,activator has no effect on potlife.Activator is not sensitive like a urethane hardener,it is basically alcohol and water.As soon as you mix a formula and before you add activator your potlife has started.
What are you painting?A pint is not going to go very far.If you have never sprayed autowave it is a lot different than solvent.You spray it at 29-30psi for you first coat(should be wet like clear,almost running your metallics should be swimming,this is very important for metallic control)second coat is medium wet,third coat is tricky,drop your pressure to 22-24psi and increase your distance to 12-16 inches using full trigger.If you have any questions just ask I spray this stuff every day.Oh by the way nason clear won’t work.
Jayson’s advice is very good. Follow it and you will be good. The only tricky part can be the control coat. Go slow and not to dry and not wet. Kinda peppered looking.
If it’s a silver it probably contains 777. It only has a 24 hour potlife. I’m not sure if that is after mixed or after activated. I can check for you tomorrow or maybe Jayson or Joe will know. If the guy at the store added LP to it don’t worry but I would check on it before spraying. I always mix and spray it so I haven’t run into this.
For a metallic reduce at least 30-40%.
Play with different guns also. I mainly use a Sata 1.4 HC but some colors that have been tricky my Iwata 1.4 LVX has worked really well.
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