Primer advice

[Bucks]

I am spraying doors in our house with water-based Dulux Trade Diamond Satinwood using a HLVP sprayer.
Up to now I have sprayed old varnished doors after priming with Zinsser BIN, then a couple of coats of Dulux Trade quick drying primer Undercoat before about 5-6 coats of the Satinwood,
They look pretty dam good if i may say so myself

My problem now is with the new/bare wood doors, I have started with priming with the above primer, but with it being water-based I am getting a lot of raised grain, after a good sanding & about 6 coats of the Satinwood you can still see the pattern in the wood grain.

So finally to the question, how can I prevent this raised grain?
Can I prime with oil based, then the satinwood on top of that
Prime with the Zinsser Bin, but my instinct is that it will just sit on top of the bare wood & not realy soak in.
I am wanting the best professional looking job which will last.

Any advise would be much appreciated

 

[opps]

BIN is fine as a primer but if your HVLP gun has a non stick lining on the cup clean it out immediately after use as it will eat the non stick.

Wash the gun through with meths then household amonia

You might need to add a little pure alcohol or meths to aid atomisation as BIN is quite thick.

 

[Bucks]

Thanks opps, for your valued advice once again,
with the BIN I am buying the aerosol cans as I realised that it would probably ruin the spray gun putting bin in it, I am just using the HVLP for the water based.
I think we are going to stick with the water based primer on this next pair of doors, otherwise we will have one pair that will look flat like MDF & another pair that have the woodgrain showing, we have decided the woodgrain showing through looks ok, you can tell it is a timber door rather than looks like MDF.

Thanks again for your help, It is worth knowing that I can use the BIN on bare wood for other areas.

 

[joe-90]

Six coats of Satinwood? What did you do that for?

 

[Bucks]

It was sprayed on, so the coats are a lot thinner than if it was brushed on.

 

[opps]

To be fair that does sound like a lot of coats, or that you have thinned more than you needed too. Waterbased paints are very difficult to atomise. I have a £500 Fuji unit that struggles. You might want to add less water and add some Floetrol instead, then hopefully 2 or 3 coats will suffice.

I don't know which HVLP unit you are using, most are shipped with the "general" size 4 needle, that should be ok for what you are doing.

Ultimately if you are happy to apply that many coats then go for it, more is better

 

[Bucks]

I have the Earlex HV5000 came with a 2mm needle set, but I bought & use the 1.5mm needle set.
I don't seem to be able to get the Primer/undercoat to atomise properly, but when its dry it looks fine.
With the satinwood I thin it down with 50% water & it atomises fine, about 3 coats might be ok, but as you said more is better, once I'm set up for spraying, a few more coats doesn't take much more time & effort.

With the two above water based paints with my Earlex HV5000, Floetrol just doesn't work, it just spits & farts the paint out, I had a right carry on when I first bought the sprayer, until I realised it was because of the Floetrol I was automatically adding, my conclusion was that the Floetrol was more for the high pressure sprayers.

 

[JohnD]

with all these coats and sanding, and the extra water thinners making the grain swell, I wonder if it might have been less trouble to use a brush

 

[joe-90]

Boyz with their toyz.

 

[Bucks]

with all these coats and sanding, and the extra water thinners making the grain swell, I wonder if it might have been less trouble to use a brush

The grain also swelled when we brushed on the water based primer on some new dado rails, so I'm not sure if it is down to the thinning for spraying,
The raised grain isn't realy a problem, you can see a slight wood-grain so you can tell the doors are solid wood & not Flat like MDF.

These sprayed doors still look 1000% better than any doors that anyone can paint by brush,

My motto is if a jobs worth doing its worth doing properly, or if your not going to do it properly don't bother doing it in the first place.

 

[Bucks]

sorry, removed this last post after reading a couple of recent ongoing threads.

 

[opps]

Hi bucks

I too have a turbine based HVLP- one of the Fuji units but I do believe that floetrol helps- i do still need to add water as well, just less of it.

Did they give you a viscosity gun. It is like a funnel, you count the speed at which the paint drips thru it.

With regard to grain swell I totally understand what you are saying, indeed it might be the case that pre painting the grain was swollen anyway as the timber adjusts to the relative humidity of the room.

Anyway glad it is working out for you.

BTW don't forget to clean the air filters out on a regular basis, if the turbine gets dust on the blades it could burn the motor out.

Best of luck

 

[Bucks]

Thanks for the info opps,
I did get a viscosity cup with it, also thanks for letting me know how important it is to clean the filters.

Just got two more glazed doors fitted today, so I am about to spray a couple of coats of the primer/undercoat on tonight, so I can get the satinwood on tomorrow.

 

[Bucks]

Hi opps,

I am usually spraying a couple of coats, then a light sanding just to de-nib,
is this ok/right?

 

[opps]

Sound fine. keep it up!!!