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Problems with SN100C in a Soltec Delta C Wave

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Hi, We have spent the day trying to profile our Vitroncis... - Jun 09, 2006 by Grant  

#42071

Problems with SN100C in a Soltec Delta C Wave | 9 June, 2006

Hi,

We have spent the day trying to profile our Vitroncis Soltec Delta C wave with the new SN100C solder, but having problems with the heavy pins on some BNC connectors we are using.

We have Interflux no residue flux, and we are using palettes, which are a little thick, but worked ok with lead based solder. We have two heat zones on the bottom, with cal rods, and then convection zone just before the wave. We also have top side heat lamps just before the wave as well.

We have tried the pot at various temperatures of 270, 280 and we even tried 290 dec C.

We don't seem to be getting enough top side heat into the BNC connectors which are all metal, with fairly heavy pins into the PCB. Everything we try it's like there is not enough heat into the PCB. But slowing down the conveyer causes bridging.

We also cannot raise the top side heating greater than 60%, so we cannot do what we normally would with a BNC connector not soldering and that's raise the top side heat.

We have kind of given up at the moment, and will try again on Monday with some other fluxes to see what's happening.

However someone said to us we might need three heat zones on the wave. Is that true?

Is anyone else running a Delta C for lead free soldering of multi layer boards with heavy connectors such as BNC connectors in them?

Regards,

Grant

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Professor Besserwisser Dr Dr PhD

#42072

Problems with SN100C in a Soltec Delta C Wave | 9 June, 2006

I think You should try to do the Delta X test, because there is a mine somewhere in the universe that has the bahodium who take care of all of this. Hahahaha I couldn't resist.

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Professor Besserwisser Dr Dr PhD

#42074

Problems with SN100C in a Soltec Delta C Wave | 9 June, 2006

I am sorry, but I hope No hard feelings? :) As for an answer to Your question: No I can not see the reason for using three heat zones on the wave. Anybody else?

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#42077

Problems with SN100C in a Soltec Delta C Wave | 9 June, 2006

Hi,

Very funny, and I feel so much better not because of your advice, but because your a Dr Dr PhD, and we all know thats more important than experience!

Seriously though, so you think we should be ok with the zones we have? We are not sure, and some suppliers told us we should have three zones, so you never know. They just want to sell us the upgrade, so you don't know if their advice is good or not.

The same suppliers suggested we replace the bath, however it's titanium coated for lead free, and does not need to be changes, and it was only on the forums that people suggested flushing it with tin, which worked really well.

So I thought I would put up a post asking people about their experiences profiling with a Delta C. Everyone seems to love the SN100C alloy, and from the smaller components that are soldering nice, it looks good, we just need to get a handle on getting the BNC connector body pins soldering correctly.

Thanks for your help

Grant

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#42080

Problems with SN100C in a Soltec Delta C Wave | 10 June, 2006

Dont't bother to answer real idiots!

I can relate to a similar problem. We also use SN100C alloy and the solder pot get(got?) contaminated with the alloys from the SAC305! How can this be? Strange thing happens during the soldering process, and it only req. 0.2 % of cantamination of our/any solderpot to cause problems. The copper for instansce; it is just enough to heat it up in the solder pot and it will immediately give away enough material so that it will be almost impossible to use the solder pot afterwords. How can we determine the solder pot life time? This very exspensive stuff! Before we took samples of the solder once/month and send to (haha) a mine laboratory that has the equipment to do analysis. But now, after the RoHS, hey, we don't even know the "the how and to" and how more often we need to do these analysis anymore. So, soldering connectors are by far the hardest task to do in a RoHS environmet! I don't know if You feel any better after this, but You are sure as h-ll not alone. I hope that I understod Your problem correctly, sorry that I could not give You the right answer. /Sincerly

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Dr. Bocephus H good time budwieser Expert Guru Phd. DDs. Wow!

#42082

Problems with SN100C in a Soltec Delta C Wave | 10 June, 2006

Yeehaa! there little doggies, y'all just got to mine that there smuckonium or that there, other stuff that fella dr. guru recomends. Doin' that and all yer problems magically dispear. Grant, sounds like you're in a tree like a one balled coon chasin' a buckaroo sitting on a pimple. Being that I put a Dr. and a Expert Guru in front of and after my name I am an expert in this field. So here goes! I reccomend usin' a propane torch and liberal doses of Organic flux on the top side of your board. But don't wash off the flux, because some guy in shipping said it was ok to ship like that.That way you kin gittteeeeer duun! As Larry the cable guy would say if he was a wave master or an expert guru. Garunteeed, that ifin y'all follow my expert advise, Y'all won't have to worry about this problem for very much longer, But make sure y'all do an expert analysis of the ramifications of the synergy that this problem or opportunity creates for your organization, maybe you should ignore the problem because it creates so much synergy and gasification with in your plant. Dr. Bocephus H good time budwieser Expert Guru Phd. DDs. Wow!

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Wave Master Larry

#42086

Problems with SN100C in a Soltec Delta C Wave | 11 June, 2006

Grant,

I beleive your problem may lie in the top side heater. Only 60% seems too little. I need to run my Soltec way past 60% to get top side wetting on larger part. You may want to have someone fix that. Perhaps Dr. Bocephus H good time budwieser Expert Guru Phd. DDs suggets why its only running 60%.

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JimC

#42093

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

Flux: Getting enough- is the spray fluxer getting good through-hole penetration. Try cranking it up. Soltec spray fluxers are not really as good as Ultrasonic Systems or Sonotek ultrasonics or the new ServoJET, but should do the job. Also, try another flux. Just because it worked for Pb process does not mean its up to Pb Free Top Side Preheat: Soltec has weak preheaters in general. I like forced convection top and bottom. Try cranking that up to the maximum. Try to achieve equal board temp top and bottom (top location where you're having the problems) just before you hit the wave. Pot Temp: Is high at 270C, try 255-260C which is normal. In this case too hot may not be good.

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Chunks

#42094

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

Hi Grant,

Boy, how do I say this - I might have to agree with Wave Master Larry. (Yeah, yeah - I know; Davef and Dr. Shocker will "burn me" again) "We" also solder large thru-hole connectors on with a selective solder machine. They measure 4 by 8 inches in fact. While running evaluations between machine manufacturers, top side preheaters made a world of difference in top side wetting. So maybe only running your top preheater at 60% just isn't hot enough. As for 3 preheaters from the bottom may help, but top side heating is truly the key for larger thru-hole parts.

Dr. Bocephus H good time budwieser Expert Guru Phd. DDs. brings up many good points, but I never trust anyone that can't spell Budweiser right, or with DDS in their title!

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#42096

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

Hi Grant,

You definitely have a pre-heat problem and not a flux problem. Pallets together with the BNC connectors put a large thermal demand on your pre-heating. 3 zones would be a good investment even with leaded solder due to the high thermal demand of your thick pallets and connectors. 3 zones will give more "time" and more "energy" needed in your situation. Lamps are not a good way of heating; they are short wave and can only heat the surface not a mass. By the way the flux you're using can handle heat very well and can solder leaded as well as no-lead. This doesn't mean I endorse lead-free as a reliable process. Similar thread here: http://www.smtnet.com//forums/index.cfm?fuseaction=view_thread&CFApp=1&Thread_ID=9674&#Message38754

Best Regards, Patrick

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cuculi54986@yahoo.com

#42101

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

My brother-in-law is a DDS and I trust him. We had some problems with solder voids in the past, and he was invaluable. He'd drill them out and fill them with SAC3240X+.

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Chunks

#42105

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

It's hard to believe MoonMan spends this much time typing these rants. Guess the boys at ever so much higher I.Q. standard of engineering, IPC, kicked him out there too.

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#42114

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

Hi,

Thanks guys for all the suggestions. I am going to check what options we have for top side heating.

Do people recommend we get convection for that?

Also, we seem limited to 60% in the machine setup, and does anyone know how to run the top lamps at a higher level.

It does seem like a top side heating issue causing the issues because the signal pins seem ok on BNC connector and they are soldering well, but the large pins on the metal of the connector are not soldering right, and that's normally solved by top side heating.

But in this case we cannot run the top side lamps more than 60%. When we enter in a larger value, the number reverts back to 60%.

Regards,

Grant

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Kip the Expert at all Things SMT

#42115

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

Hi.

I agree that the Soltec has weak, low-wattage preheaters, and also, the Soltec's fluxer is flippin' weak too. It doesn't do a good jab of atomizing the flux and getting good, huh-huh, penetration on the holes. I cranked up my Soltec's pressure to 200 BAR.

I, too, have had issues with BNC connectors. It appeared that the mechanical hold-down leads on the sides were made of a non-wettable brass-type material.

Grant - go back and do process characterization. Determine through thermal profiling how much heat that area is REALLY getting, and pull the data sheet on that BNC connector as well to get confirmation on alloy type. i don't want to tell you how to do your jwob or anything.....

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#42126

Problems with SN100C in a Soltec Delta C Wave | 12 June, 2006

Hi,

Thanks, and we are doing that today. After spending the day playing with all the usual things that used to work, we are focusing today on profiling and data to get things right.

The only worry I have is did we get a wave that can handle this, and have others got better pre heating than we have, so we might have to upgrade.

Has anyone upgraded a Delta C with top side convection? Can it be done?

Grant

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Grant

#42132

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

Hi,

ok, I have a bit more info after playing further with the profiling.

We are getting close, but we don't have enough top side heat I think. The IR lamps just don't give enough, but we can get better connector that should help.

But we have another weird issue on another board we are doing. We have a profile that's perfect on a board that's previously been waved, where all the connectors are soldered.

However when we run it first time with new connectors, we get serious bridging on the DVI connector. It's odd, because everything else is soldered ok, but the DVI connector is bridging.

We are also getting some solder stuck to the PCB in various spots, and it's like small solder smears.

The problem I have is I am not a wave guy, but more of an SMT guy. So any help people can suggest would be great!

What is the typical cause of bridging, and smear of solder on the PCB?

Grant

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#42136

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

Well grant just to let you know i feel your pain. I've been wavesoldering with sn100c since January and let's say i'm still learning everyday. Some of the typical causes of bridges are not enough flux when the board hits the solder. Also it can be board is in the solder bath too long. And the big difference between lead and lead free solder is if the board is too deep in the solder this also can cause bridging. But since you say you are getting solder spots on the pcb i'm leaning towards not enough flux. Now if this is only happening on the first board you are running it sounds like your fluxer might be the problem.Without being familiar with the fluxer you are using it might be it's cleaning itself in between runs and might have some alcohol or water in the head of the fluxer instead of just flux depending the flux you are using. An easy solution is if it's just the first boards on the pallet is put blank boards in those locations. If you are going to be trying different fluxes out,I personally have found out that more active fluxes have worked better for me. A little suggestion on your original problem is if your connector is on the board edge leading into the wave and if your pallets are thick try taking a file and put an angled egde leading up the board edges so the solder can rise up quicker there instead of skipping across the difference between the pallet and board thicknesses. You also can try running a sample board the opposite way you normally run it and see if you still have the problem. The one thing you have to realize between lead solder and lead free solder is that the surface tension on lead free solder is a lot greater then lead solder. Hope i was some help to you.

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RDR

#42141

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

Your new problem is inadequate flux coverage.

This may be a contributer as well to the BNC issue.

Russ

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#42142

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

As I mentioned in another thread, I've always been one to flux the living crap out of a board until the ICT guys start yelling at me, which actually did happen last week. I had a little oriental guy (an immigrant to Riyadh from Vietnam), clicking and popping that he's having to clean his ICT bada-bings (pins) too much because, Nagheenanajar, the wave guy, puts too much flux on the board.

Anyway, I'm rambling...back to your solder shorts...I have no experience yet with SN100, but to combat shorts on Sn-Pb, I've always, 1.) Flux the Bejeezus out of the board...and 2.) SLOW DOWN your conveyor and/or 3.) Turn down your chip and laminar wave.

The slower you run, the less your overall contact length will be (ie you're dragging less solder), and the better the peel-back. If you're running a weak flux where the activators burn off in the chip wave, shut the chip wave off if you absolutely don't need it.

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#42143

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

Hi,

Your right guys, and we turned off the chip wave, and most of the problem went away. It looks much better, and we are getting a slight bridging on a USB connector at the front edge of the PCB and a little adhesion, but not any where as much as when we had the chip wave on.

So it must be the chip wave burning off the flux. We had a fair bit of flux, and perhaps we might turn up the pressure, and reduce the pump pressure, to get better atomization of the flux.

Funny, with all the stuff we have learned going through this process, we are actually getting better top side fillets on all the connectors than we had with lead based solder. It's just a few connectors that are still causing a problem, and once those are sorted out we should be ok.

Thanks for the ideas, and I will keep working on it, but we should be back in production with some products tomorrow, so my heart can start running again hopefully!

Regards,

Grant

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#42168

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

Hi,

Is it possible to have too much flux?

Grant

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Hoss

#42169

Problems with SN100C in a Soltec Delta C Wave | 13 June, 2006

Samir's ICT guy says YES.

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#42177

Problems with SN100C in a Soltec Delta C Wave | 14 June, 2006

Yes it's definately possible to have too much flux. You'll see a white residue film on the board. In the past we have had hipot issues cause of too much flux residue ,left on the boards. You defininately don't want to be using a no clean flux and still have to clean boards kinda kills the whole purpose of it.

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Rob

#42189

Problems with SN100C in a Soltec Delta C Wave | 14 June, 2006

What rpm is the Delta wave going at? (I think it was recommended to have it running at 700-800 rpm even if you are not using it, otherwise you get a dip in the main wave)

At least that's what I think I remember from a trip to their factory, but they may have been beer re-inforced recollections, or implanted memories from the esteemed Dr Shocker.

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#42199

Problems with SN100C in a Soltec Delta C Wave | 14 June, 2006

Hi,

Thanks for all the help guys, and we did a bunch of things to get it working. We raised the pump speed, and also went to a water based flux, which helped a lot. We also reduce pre heat as we were burning off the flux.

It's doing really nice joints now, and this SN100C is very nice. We are fully RoHS finally now, just in time, and it took longer than I expected to change over, but seems to be working really well. The boards are more shiny than I expected, as a lot of people had commented on how dull the joints look, but the Koki paste looks good, and the SN100C wave also looks good.

Regards,

Grant

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