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Author	Comments
Yvan Richard Posted: Jun 01, 2010 11:12 PM	Spraying Fingers I have a brand new tip and I am getting fingers. I have taken the tip out to clean while spraying and it works ok for a while then back to fingers. I like to spray with very low pressure around 700-850 psi? Could my pressure be too low? The low pressure normally allows me better control for a better looking job.
quentin Posted: Jun 02, 2010 11:07 AM	You may need to drop your heat too and up the pressures a bit. The foam is setting up too fast in the tip it sounds like. Also remember to drill it out constantly when you see it starting to happen.
mason Posted: Jun 02, 2010 11:46 AM	I would strongly caution against spraying with low pressures. You need to have sufficient pressure to mix the foam properly. Using low pressure can cause a whole host of problems that are not visually apparent, such as insufficient closed cell content, (60-70% instead of 90%, poor cell structure, poor dimensional stability (leading to shrinking foam, incomplete mix of chemicals causing odor problems and more. In order to control the foam better, just use a smaller mixing module and PCD or mixing chamber. If you have a Fusion gun, try using an oval shaped pattern, It is easier to control in stud wall cavities.

Author

Comments

Yvan Richard

Posted: Jun 01, 2010 11:12 PM

Spraying Fingers

I have a brand new tip and I am getting fingers. I have taken the tip out to clean while spraying and it works ok for a while then back to fingers.
I like to spray with very low pressure around 700-850 psi? Could my pressure be too low? The low pressure normally allows me better control for a better looking job.

quentin

Posted: Jun 02, 2010 11:07 AM

You may need to drop your heat too and up the pressures a bit. The foam is setting up too fast in the tip it sounds like. Also remember to drill it out constantly when you see it starting to happen.

mason

Posted: Jun 02, 2010 11:46 AM

I would strongly caution against spraying with low pressures. You need to have sufficient pressure to mix the foam properly. Using low pressure can cause a whole host of problems that are not visually apparent, such as insufficient closed cell content, (60-70% instead of 90%, poor cell structure, poor dimensional stability (leading to shrinking foam, incomplete mix of chemicals causing odor problems and more.

In order to control the foam better, just use a smaller mixing module and PCD or mixing chamber.

If you have a Fusion gun, try using an oval shaped pattern, It is easier to control in stud wall cavities.

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