Absolutely correct.



-----Original Message-----

From: TechNet [mailto:[log in to unmask]] On Behalf Of lduso - Diamond-MT.com

Sent: Thursday, September 22, 2016 9:19 AM

To: [log in to unmask]

Subject: Re: [TN] Fwd: coating complaint



A very common mistake people make: if it does not glow, then there cannot be any coating there. It's hard to deny that it is present when you can plainly see the material under white light. Granted, it may not be at the minimum thickness required but it is there. I like inspecting the overall coating under white light first and use the UV light to inspect the coating-free areas that are tougher to see.



Lloyd Duso

Plant Manager

Diamond-MT

(814) 535-3505

www.Diamond-mt.com



On Thu, Sep 22, 2016 at 9:56 AM, Guy Ramsey <[log in to unmask]> wrote:



> I am in over my head. I have little to no experience with conformal 

> coating. Can anyone with more experience comment?

> thanks,

> Guy

> ---------- Forwarded message ----------

> From: Guy Ramsey <[log in to unmask]>

> Date: Thu, Sep 22, 2016 at 9:51 AM

> Subject: Fwd: coating complaint

> To: [log in to unmask]

>

>

> I sent this message on to a friend who posts images for review by 

> members of the IPC technet.

> We are looking for technical support and user experiences with this 

> material.

> If we inspect at 5x-10x magnification we can observe the conditions 

> that our customer is complaining about.

> But, our application process seems well controlled and the condition 

> does not exist when the material is first dispensed. The material 

> flows as it cures and becomes thin at the edges of the components. 

> Thin enough so that is does not glow under UV light. In some instances 

> components appear to have no coating (when viewed under UV). However 

> under normal light it is easy to see the parts are coated.

> Is this normal behavior for the material?  Can we expect normal 

> performance from the the coating?

> Guy Ramsey

>

> ---------- Forwarded message ----------

> From: Guy Ramsey <[log in to unmask]>

> Date: Thu, Sep 22, 2016 at 9:41 AM

> Subject: coating complaint

> To: Steve Gregory <[log in to unmask]>

>

>

> Hi Steve,

> Can you post these images on your homestead page for the group please?

> The images are of acrylic coating  Humiseal 1B31. We are applying a 

> thinned mix using a dispenser through a fine needle (25AWG).

>

> Under room lighting we can see coating. Under UV light, at this 

> magnification our customer is complaining about skips. I don't have 

> enough experience with the material to know if this is normal or not.

> Notice how the resistor appears to have no coating under UV, but in 

> normal light it is clearly coated.

> Also notice how the coating flows off of the components at the edges, 

> leaving only a thin coating that may not glow under UV light.

> Are these normal attributes of this type coating.

>

> We do not see this with Urethane spray coatings.

>