SW KA+ problems with dark colors only

[GadgetGuy]

We have been shooting KA+ system for our cabinets for past 2 years with good success, except... dark colors mixed by Industrial Coatings group.  Seems to be hit or miss - some darks shoot fine with no issues, but others have following problems:

[list type=decimal]
[*]premature drying - literally top half of a large door/wainscot panel dries before we can finish bottom half!
[*]not sure of this problem (neither is SW) - pin-sized "bumps" - no rhyme or reason -- I believe it be to related to #1 - I think air bubbles trapped under surface are not being released because like #1, paint is drying too quickly for bubbles to release.
[/list]

Notes:

• 65-70 degrees F.
• low relative humidity
• Fuji 4-stage - #4 tip
• KA+ surfacer and top coat
• straight from can -- full strength -- no retardant
• NO issues with light colors - only dark

We dialed down the paint volume on gun -- made slower passes. This seems to help a little, but does not problem go away.  Part of problem with current job is SW formulated the paint with too much sheen and our spray tech did not notice till 1/2 job was completed.  As a result every imperfection is magnified.

Our SW rep wants us to shoot Emerald Urethane for the dark colors, which makes me suspect SW is aware of problem but doesn't want to advertise the problem.

Has anyone with KA+ experience seen this?  How to fix?

Mark

 

[JCLP]

Mark,

Sorry to hear that you are having diffculty. I don't have much experience with KA but have lots with Emerald Urethane. I don't know what sheen you are using, but Emerald Urethane Satin leaves a chalky feel to the surface if you follow the TDS recommndations for tip size and pressure. I hear the semi-gloss version works much better. They only way to get rid of them is to spray the second coat really thick then you run into it not drying and remaining tacky. A useless and crappy product.

I am now using SW Pro Industrial Waterbased Alkyd urethane. Sprays thinner, lays done nicely, levels well and dries much faster and harder then Emerald Urethane. 5H pencil hardness in 7 days. The low gloss version is very dull, so I'm spraying the semi gloss.

Good luck,

JC

 

[tjbnwi]

[member=15240]GadgetGuy[/member],

Problem is your store. That's why they don't know the answer to this situation.

You're describing micro foaming in #2.

You need to call the Products Finishes store in Countryside, they have special binders to make the dark colors work. It holds the pigment in suspension. The Product Finishes store are the only stores that have access to it. Their phone number is 708-482-8131, they used to be my primary finish supplier.

The dark colors are mixed in clear bases, I use a 1.0 tip for the clear based products in the Fuji. Make sure you spray the edges first.

If you're going to be doing a lot of spraying, look into a Graco Merkur pump. A 15 to 1 will shoot the KA+ finishes well using a X09 or x11 flat tip. A 3/0x6/8 door is 15-20 seconds top to bottom. Check Graco's website, they used to have a try before you buy program. It does take a compressor that will supply about 7 CFM@ 100 psi if you're running wide open. I run a Schultz which is 18 CFM @ 180 PSI.

If you go with a Merkur (or Kremlin) let me know, I'll get you through getting it dialed in. In the photo in my other response, you can see the 4 sprayers we use constantly.

Not sure where you are in Chicago, but it's my hometown. Southwest side....

Tom

 

[tjbnwi]

[member=24938]JCLP[/member],

The pre catilized Pro Industrial epoxy is also very nice to shoot.

It was good talking to you the other day, it's been to long.

Tom

 

[Mike Goetzke]

[member=15240]GadgetGuy[/member],

Problem is your store. That's why they don't know the answer to this situation.

You're describing micro foaming in #2.

You need to call the Products Finishes store in Countryside, they have special binders to make the dark colors work. It holds the pigment in suspension. The Product Finishes store are the only stores that have access to it. Their phone number is 708-482-8131, they used to be my primary finish supplier.

The dark colors are mixed in clear bases, I use a 1.0 tip for the clear based products in the Fuji. Make sure you spray the edges first.

If you're going to be doing a lot of spraying, look into a Graco Merkur pump. A 15 to 1 will shoot the KA+ finishes well using a X09 or x11 flat tip. A 3/0x6/8 door is 15-20 seconds top to bottom. Check Graco's website, they used to have a try before you buy program. It does take a compressor that will supply about 7 CFM@ 100 psi if you're running wide open. I run a Schultz which is 18 CFM @ 180 PSI.

If you go with a Merkur (or Kremlin) let me know, I'll get you through getting it dialed in. In the photo in my other response, you can see the 4 sprayers we use constantly.

Not sure where you are in Chicago, but it's my hometown. Southwest side....

Tom

[member=4105]tjbnwi[/member] That place is a stones throw away from my work!

 

[tjbnwi]

@MikeGoetzke,

Then so is this place. Randy and Kathy are in-laws on my wifes side.
https://www.formellagourmet.com

Tom

 

[tjbnwi]

[member=15240]GadgetGuy[/member],

A picture taken in July on the Chicago Riverwalk. (Has nothing to do with the thread, just showing off "my girls").

Tom

 

[GadgetGuy]

[member=15240]GadgetGuy[/member],

Problem is your store. That's why they don't know the answer to this situation.

You're describing micro foaming in #2.

You need to call the Products Finishes store in Countryside, they have special binders to make the dark colors work. It holds the pigment in suspension. The Product Finishes store are the only stores that have access to it. Their phone number is 708-482-8131, they used to be my primary finish supplier.

The dark colors are mixed in clear bases, I use a 1.0 tip for the clear based products in the Fuji. Make sure you spray the edges first.

If you're going to be doing a lot of spraying, look into a Graco Merkur pump. A 15 to 1 will shoot the KA+ finishes well using a X09 or x11 flat tip. A 3/0x6/8 door is 15-20 seconds top to bottom. Check Graco's website, they used to have a try before you buy program. It does take a compressor that will supply about 7 CFM@ 100 psi if you're running wide open. I run a Schultz which is 18 CFM @ 180 PSI.

If you go with a Merkur (or Kremlin) let me know, I'll get you through getting it dialed in. In the photo in my other response, you can see the 4 sprayers we use constantly.

Not sure where you are in Chicago, but it's my hometown. Southwest side....

Tom

Hi Tom - have followed your threads for some time now...  Regarding your comments above:

1) believe it or not, but my store is Countryside.  They have been mixing our dark KA+ colors for past 2 years.  When I first noticed the pin holes, I thought about micrfoaming, but not having seen it, I wasn't sure.  Having shot a few more panels unsuccessfully this week, I have say we have 2 issues (although they may be the same):
  a) pinholes
  b) dried peaks that almost look like dust particles

Neither problem is going away, and I don't have a solution yet.  I will research microfoaming a little more, but can you explain what causes it and how to avoid?  Why only dark colors?  Is it related to the total volume of colorants in the suspension?

btw - we're in Naperville.

Thanks, Mark

 

[tjbnwi]

[member=15240]GadgetGuy[/member],

No reason for me not to believe you. I am amazed they don't have an answer. Never experianced that with the Countryside store.

The dark colors are normally mixed in clear bases. I shoot clears through the 0.8 nozzle/needle set in my Fuji's.

Let me think on thos a bit, I may have to recommend a small pressure pot, sounds like the film build is not there.

Do you have a wet mill gauge? I not SW should be able to give you some.

I think my Napperville electrical license expired last May/June.

Tom