HVLP spraying

[karl]

Hi guys

Anybody got any experience of spraying water based paint/primer using HVLP? I got a Fuji system and am experimenting. It comes with a 1.3mm needle, and Fuji reckon that is what you need. But I think it's too fine - Johnstone's recommend a 1.5mm, and another paint supplier recommend 1.8mm for their waterbased products.

Any input greatly appreciated.

Cheers

Karl

[nickw]

1.8 if you want to use it neat, dilute it for smaller needles.

[york33]

I use 1.8mm for waterbased primer and topcoat, works well.......

[karl]

Cheers guys - i'll order a 1.8mm set for it.

Karl

[york33]

Good plan, at least it works for me that way. Primer sprays out the can, topcoat does in the summer and has a splash of water in the winter!

[karl]

Just a follow up question.

Do you run more than one gun for paint/prime? If so, will any "HVLP" gun work with the Fuji turbine (hose connection???), or does it have to be a Fuji?

Thanks

Karl

[promhandicam]

Hi guys

Anybody got any experience of spraying water based paint/primer using HVLP? I got a Fuji system and am experimenting. It comes with a 1.3mm needle, and Fuji reckon that is what you need. But I think it's too fine - Johnstone's recommend a 1.5mm, and another paint supplier recommend 1.8mm for their waterbased products.

Any input greatly appreciated.

Cheers

Karl

Hi Karl.
Out of interest, what primer are you planning on spraying and is this for furniture or something else? I use Morrell at the moment, but would be interested to know if using a trade primer is a viable alternative. I have in past used Johnstone's mdf primer but have applied it with a roller

[karl]

Hi Steve

I have looked at both Morrells and Symphony Coatings. I know a few people who use Symphony and swear by it.

Water based prime at the moment is Johnstone's, but I found it needed that much watering that it caused lots of fluffing ( - love that word!) issues on the MDF. Curiously the top coat didn't need thinning by more than about 5%, and once the new needle arrives, i'm no thinning at all. I'm also hoping that a dedicated primer designed for spraying will cause less fluffing. If not, I will need to look into getting my extraction vented through the roof so that cellulose primer can be used.

Edit: Latest island unit sprayed with water based. No paintbrushes were used in the painting of this island....



Cheers

Karl

[Tomyjoiner]

I was told by my rep and read that waterbased paint is flamable when spraying just like 2k but not as bad and is toxic coz of the way its made. Watched a few clips on the net of people explaining it. Its water based but with loads of nasty chemicals aswell.

[houtslager]

the environmental aspects of water based paints make me laugh.
The old oil based paints were biodegradable tough and their finishing was great, whilst
the new water based paints are troublesome, finnicky, and are not environment friendly - made from plastic derivatives thus not at all friendly to man or the environment.

There, that's my rant over on WB finishes

[mark270981]

I've just invested in an airless sprayer for priming, It was a recommendation although I am not convinced until i try it out.

[sainty]

I've just invested in an airless sprayer for priming, It was a recommendation although I am not convinced until i try it out.

I think you'll love it mark. We use airless for priming and it's very quick and leaves an excellent base for top coats.

[karl]

What's an airless sprayer? Is that the aaa system???

[mailee]

Think I'll stick with my ozone destroying, cancer causing, anti social solvent stuff, much easier to get on with.

[ispraywood]

AAA is by far the best method for both priming and top coat (with some exceptions where conventional/compliant has benefits) The transfer efficiency is by far the best with AAA too. And I have to agree, I much prefer solvent based paints as they tend to be much quicker, and generally easier to get on with, again with the exception that you have the added expense of having solvent to purchase to clean up with and dispose of afterwards, it is still my preferred choice.

A mistake that lots of people make is that most professional finishes used within our industry are water born, not water based. They are two completely separate things. Water based paints become soluble in water after application which clearly would not work considering most external coatings we use now you clean up with water. Water born paints, however is where the paint solids are suspended in a water carrier, which evaporates, partly at atomisation, but mainly after the finish has coated the surface, and then leaves the paint finish on the surface. As already pointed out, water born paints can still be flammable if there is sufficient PPM within the atmosphere, which is then exposed to a suitable ignition source.

Something to also note, if using a spray booth then care should be taken to avoid the spraying of lots of different types of paint onto the filters, as the mix in materials can cause auto-ignition, much like oily rags.


Hello by the way, just joined so though I would introduce myself.

[promhandicam]

AAA is by far the best method for both priming and top coat (with some exceptions where conventional/compliant has benefits) The transfer efficiency is by far the best with AAA too. And I have to agree, I much prefer solvent based paints as they tend to be much quicker, and generally easier to get on with, again with the exception that you have the added expense of having solvent to purchase to clean up with and dispose of afterwards, it is still my preferred choice.

A mistake that lots of people make is that most professional finishes used within our industry are water born, not water based. They are two completely separate things. Water based paints become soluble in water after application which clearly would not work considering most external coatings we use now you clean up with water. Water born paints, however is where the paint solids are suspended in a water carrier, which evaporates, partly at atomisation, but mainly after the finish has coated the surface, and then leaves the paint finish on the surface. As already pointed out, water born paints can still be flammable if there is sufficient PPM within the atmosphere, which is then exposed to a suitable ignition source.

Something to also note, if using a spray booth then care should be taken to avoid the spraying of lots of different types of paint onto the filters, as the mix in materials can cause auto-ignition, much like oily rags.


Hello by the way, just joined so though I would introduce myself.

Welcome to the forum and thank you for your comments. Do you just do finishing or do you make stuff as well? If you are just doing finishing are you working for a larger company or self employed. The reason I ask is that I think a number of us would like to use the services of a local specialist timber finishing company but they seem to be few and far between. I know that if you did take work in and were fairly local I would be very interested.

[ispraywood]

I am indeed a self employed wood finisher, a rare breed! I have my own workshop that is set up to spray and finish all manor of things interior and exterior. From a small box, to a whole house (literally) and anything in between.

I am based in Hampshire however I do work nationwide, either coming to collect work for processing, or by having it shipped by third party. And of coarse you can always swing by my workshop to drop stuff off.

I am also though of running some finishing schools in the summer if this is of any interest to people. And in the past, people have wanted to have a hands on aproach to finishing so have spent the time with me finishing there projects themselves.

Give me a shout if anyone would like any more information and advice.

Many thanks.

[Oneillkev]

Hi Ispraywood

At the moment I use gravity gun with compresser using 2k paints in a spraybooth.
I am happy with the finish I get but it is very time consuming having refill the cup every few mins and mixing paints, then pouring through filter into cup. Also don't like the amount of overspray.

I am looking for something with same if not better finish but with speed in mind. Pressure pot, hvlp ,aaa?

What would you suggest or what do you use?

Thanks
Kevin

[ispraywood]

Hey Kevin,
It really depends on the volume of paint you use and how frequently you use the equiptment, AAA is by far the more efficient in terms of paint usage, However quite a big investment and you must also have a decent 35cfm at least compressor to run it.

In terms of speed, given the time to prime the AAA pump and cleaning afterwards etc there is not a lot in the terms of gained time.

What gun do you currently spray with and how many litres of paint are you spraying per week? Also do you only spray with solvent based finishes or do you use a mix? When buying a AAA pump, you have to dedicate it for either solvent, or waterbased, something else to consider.