Any tips for spraying Morrell's pigmented lacquer?

[flanajb]

I have a Fuji 3 stage HVLP sprayer and am currently trying to respray out kitchen doors that were sprayed by a professional 13 years ago. Although the finish looks good it is nowhere as flat as the original spray job. My finish is quite bumpy. I am using the stock needle which according to the manual is the correct one.

Just trying to understand whether I should dial down the spray pattern so it is more narrow, reduce the amount of spray or increase the spray. I did notice that having sprayed the bumps were present when it was wet so I wonder if I didn't put down enough of a coat and hence it didn't level out?

The lacquer is waterborne lacquer.

Any tips would be welcome as I suspect I should in theory be able to get a very flat finish with the spray setup.

 

[Droogs]

just check your atomisation, like all heavy pigment paints it can dry before you get most of it on the piece and get a bitty finish

 

[flanajb]

just check your atomisation, like all heavy pigment paints it can dry before you get most of it on the piece and get a bitty finish

Sorry if I am appearing vacant, but how do I do that or even change that. Is it a case of reducing the temperature in the room or thinning down the product?

 

[flanajb]

A follow issue that I am experiencing today as well is that I have loads of micro bubbles that don't pop and dry in the finish. So yesterday was the product not flowing out level and today it is micro bubbles. Tried everything today to get rid of them and in the end gave up.

Same finish too. I even 10% floetrol to see if that would help, but the bubbles were still present. I love spraying, but it can be so unpredictable when you are spraying in an environment that is not temperature / humidity controlled.

 

[Droogs]

Spray on scrap first and check the finish if looking bitty then adjust gun down or thin paint if you cant. Get a viscosity cup to check the paint is at the right runniness. Don't have the place too warm while spraying or too cold either

 

[flanajb]

If anyone else has sprayed morrells Fastmatch pigmented waterborne lacquer using a hvlp spray setup. Can you tell me what needle size you used and did you thin down the material.

I have the standard 1.4mm needle, but when I did a viscosity test it took 60 seconds to run through and therefore suggests I need the 1.8mm Fuji needle.

The paint was quite cold mind so that wouldn't have helped. A new needle for the Fuji XPC gun is £62 and given I only need to spray 6 cabinet doors it's more expense I could do with out.

 

[johnnyb]

just to put my twopence in. the 1.4 is best for clear lacquer I reckon. the 1.8 is a better size. but i dont like fuji guns. i much prefer graco.the turbine doesnt seem to make any difference tbh.

 

[flanajb]

Thanks. I eventually purchased a 1.8mm needle, but found that thinning the product down and using the 1.4mm gave the best results.

 

[Droogs]

Do you feel that the V cup helped. i wouldn't prepare paint without mine

 

[sometimewoodworker]

While in a completely different environment to yours and using completely different equipment and finish, but still water based, I’ve just been spraying about 20 panels most 60cm square and spraying them flat gives me the best results.

They start out bumpy but then flow flat. They are dry To the touch in less than an hour

 

[flanajb]

Do you feel that the V cup helped. i wouldn't prepare paint without mine

Yes. I hadn't really used it before. It certainly made me realise just how much temperature affects viscosity. A cold can in the garage, compared to said can stored in the airing cupboard was about 30 seconds.

 

[RobinBHM]

Waterborne finishes are tricky.

There is a fine line between spraying a coat that has insufficient film build and doesn't have full wet coverage and at the other end too heavy a coat that runs.

I use a 1.6 tip on a SATA 1000 B gun (actually I mostly use air assisted airless with an 11 thou tip, but not the same technology)

Thin the material about 5% and try spray outs. You need to get an even wet coat.
If it's coming out dry the material is far to thick. If it's orange peel it's a bit too thick.

When drying you need airflow and steady warmth.

I find sayerlack is one of the easiest lacquers to spray. I've not used morrrells for many years

 

[flanajb]

Waterborne finishes are tricky.

There is a fine line between spraying a coat that has insufficient film build and doesn't have full wet coverage and at the other end too heavy a coat that runs.

I use a 1.6 tip on a SATA 1000 B gun (actually I mostly use air assisted airless with an 11 thou tip, but not the same technology)

Thin the material about 5% and try spray outs. You need to get an even wet coat.
If it's coming out dry the material is far to thick. If it's orange peel it's a bit too thick.

When drying you need airflow and steady warmth.

I find sayerlack is one of the easiest lacquers to spray. I've not used morrrells for many years

Clear lacquer is a dream to spray and for that I use a 1mm needle and get great results. It's the pigmented stuff that's tricky.

I'll make a note of Sayerlack for future projects.

Overall I'm pleased with the results, but if I was doing it for a living I'd want the results more consistent as I had problems with orange peel and microbubbles and found the process rather hit and miss.

I suppose a lot of that is down to inexperience of spraying.