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no tru-hole on wave

Ramon I Garcia C


no tru-hole on wave | 26 August, 2000

Hi friends:

I have a problem in the process of one PCB, I have a lot of insuficients of solder in top of the board, this pcb already was working good, but sudenly began there isn't flow thru hole, I ran the profile and it was ok, if I inmerse in a tray with flux the pcb, this work ok, I tried incresing the amount of flux but the problem continued, I have a Seho solder wave machine and it has a spray fluxer, ant my flux is no clean, MAY SOMEBODY GIVE ME A TIP HOW FIX THIS?

The others pcbs are working well.



excuse my English

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Re: no tru-hole on wave | 27 August, 2000

If you have another container of flux that is a different batch try that. Dont forget to clear lines of old flux. check spray pattern width. The activators needed may be dead in flux.Since it is sudden my question would be what just changed?

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Travis Slaughter


Re: no tru-hole on wave | 28 August, 2000

Being its sudden and only 1 product I would suspect the PCB particularly the barrels in the plated through holes being contaminated.

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Steve Harshbarger


Re: no tru-hole on wave | 28 August, 2000

Hello Ramon,

This is a very common problem that usually can be overcome. Can you tell me the flux type you are using (manufacturer, and flux number)? Has your board vendor, or type of PCB's changed (are they entec coated - bare copper)?

What is the topside temperature you are getting on the PCB (measured just prior to the solder pot)?

As Travis mentions, contamination would be the most likely problem, but there are also a number of other variables that can affect top side fill. I have a chart that can be emailed to you, which specifies the areas to look at for topside fill problems. If you send me your email address I will forward this chart to you.


Steve Harshbarger

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Re: no tru-hole on wave | 30 August, 2000

Hi Ramon,

We have had this problem before on our Seho Wave Solder Machine. We are currently using a spray fluxer as well.

By imersing the PCB into the flux you stated you are getting good results.

What you need to do is check your spray pattern. Make sure the nozzle holes are going in the correct direction. Check all flux lines for air and replace fittings if necessary. Also check all gaskets that support the nozzle. We had one just last week disintegrate (using VOC Free No Clean) and had to replace it. It caused major insufficients as well. You also need to monitor the nozzle air pressure has not changed. Just by increasing the flux will not help you, if the nozzle air pressure is not sufficent. We normally run ours on 28. Good luck, Nance Lykus (

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Ramon I Garcia C


Re: no tru-hole on wave | 30 August, 2000

Hi friends;

Steve I'm using flux Kester 959, my top temperature is 187 celcius degrees, my e-mail is, Travis I'll check the pcb for contamination, but how may I clean the pcb? may I use alcohol? Nance I cleaned the pipes of the fluxer,but not changed any gasket, I'm going to change this, RJ I was checking the flux with a paper roll for fax (thermic paper) and it's colored dark there another way to test? maybe another one more confiable.

Thanks guys for your advises.

Ramon I

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Travis Slaughter


Re: no tru-hole on wave | 31 August, 2000

How to clean a contaminated board would depend on what it�s contaminated by, alcohol may be just the thing. If there is bare copper that has corroded that could be more of a problem, or maybe not if its due to poor tinning by the board house you could reject the boards back to them. Another possible solution could be a more active flux if that is an option.

PS. Steve I would like to take a look at that list of yours too if you don�t mind.


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