Stripes after spraying ‍♀️

[Cat007077]

Hi … I’m a novice who now trying to renovate my dad’s house! So far I’ve learned, from this site, how to. Add a docket, got a vanity unit, drain, replace a d install new radiators… I was doing do well!

I borrowed a Wagner 250 and my friend gave me a brief lesson.
Of I went into newly plastered walls … mist coat on like a dream! Coat 2 … great …

Then I put another coat on (leaving correct drying time etc) … a day late I have ‘shadow’ stripes! Can someone help me .. please Paint was diluted to manu instructions
it was hard for me to see where I’d been
Is this why I have stripes?
Can anyone advise me what to do next

 

[Notch7]

what size tip were you using?

did you try any sprayouts first, was the fan pattern nice and even?

airless sprayers rely on high pressure to atomise the tails of the fan...spray pump systems like these are used in joinery but they are air assisted to break up the tails

its possible you might have been spraying slightly too close or not overlapping by 50%

 

[Cat007077]

Thanks for your prompt reply! I was using 517. Have to admit I didn’t test … cos it went on well in mist boat I thought all would be good…

How can I get rid of the stripes?

 

[Cat007077]

The stripes are vertical… should I now go horizontal???

 

[opps]

I suspect that your spray pattern was incorrect, as in not enough overlap. Wet on wet edges is key.

I say that as someone that only has a HVLP rather than airless- the same principles still apply though.

 

[Cat007077]

How do I rectify this? Should I go over horizontally? Or sand

 

[opps]

In theory it shouldn't make any difference if you go up down or left right.

I still think you are not sufficiently overlapping your spray.

Lets say, hypothetically, that the width of each pass is 30cm. About 20cm of that is solid, 5cm either side is much thinner. After the first pass, the next pass needs to ensure that the thinner edge coincides with the middle of the 20cm. It means that with each pass, you are moving over by 15cm each time.

Sorry, I probably haven't explained that very well. Have a look at image 3 on page 18

https://pt.wagnerspraytech.com/wp-content/uploads/2017/05/Control-Spray-250_0529627B_eng.pdf

 

[Cat007077]

Thank you Now I need to know how to get rid or fill in stripes ‍

 

[opps]

Thank you Now I need to know how to get rid or fill in stripes ‍

Are they deep enough to be able to feel them? Based on your description, I assumed that it was simply a case of inconsistent sheen/coverage.

My old HVLP isn't powerful enough to spray emulsion, but when spraying 2 pack paints, I do a wet on wet coat- left right followed by up down, that said, I not spraying anything larger than 8' by 4'.

 

[Cat007077]

Mine is a Wagner 250 control pro . Spraying walls and ceilings … think you are right not enough overlapping Can’t ‘feel’ them as such but can see them … think I’ll try a cost against them … did vertical will try to cover with horizontal???

 

[opps]

Horizontal is going to be awkward- unless you are 8ft tall.

Just try the old up and down but make your passes closer. - BTW most emulsions require two coats after the mist coat anyway.

 

[opps]

I completely understand it being difficult to see where you have just sprayed. If you have a portable light source you can shine it against the wall at an angle, hopefully you will be able to see the edges of the wet paint.

Sometimes, when rolling a ceiling, I turn off the ceiling lights and rely upon the sunlight coming through the window so that I can see where my wet edge is.