View Full Version : Question about wave soldering machine

05-15-2003, 02:38 PM
What kind of pump is used for wave soldering machine? I've alway wondered and the previous thread got me reminded.


Forrest Addy
05-15-2003, 03:29 PM
Linka looks like a coolant pump on steroids. Very little throw but a fair volume. The motor and housing extends far out of the solder and has a heat flinger on the shaft.

I saw only once but and that was long ago. I could see that it was intended to survive being solidified in solder. I understand modern ones are made with ceramic parts to prefent iron contamination of the solder.

[This message has been edited by Forrest Addy (edited 05-15-2003).]

05-16-2003, 12:12 AM
Yeah, that's a good description. Big clearances, nothing tight tolerance. Centrifugal pump. Not very high speed, either. Impeller is about 6" diameter if I recall.

It "only" has to produce a head of about 2 or 3 inches, but that's a heavy weight of solder. And, the wave on ours, which i think is an Electrovert, is about 2" by 20 inches wide in area.

The tank and pump on ours is all stainless steel, with some other material, maybe titanium, for certain parts.

For all its molten solder, it isn't so very hot, something like 250 to 275 C. The solder looks like mercury as it comes up and spills over the guide in the nicest shiny "solderfall".

The pump drives it up from below so that the dross will be washed aside and not contaminate things that touch the wave itself. The wave is shiny, and the metal in the rest of the pot is more drossy on top, despite having some flux on it.

Oh, yeah, the volume is such that there is always about 5/16 thick of solder flowing over both sides of the guide. That is a total cross-section of nearly 5/16 x 40 inches of solder being pumped continuously.

[This message has been edited by Oso (edited 05-16-2003).]

05-16-2003, 02:32 AM
yeah... what they said.
Just got home from work, and dug around a bit in the back of the wave.
The pump is producing 3 or 4 inches of lift on about 20% of the surface area of the solder pot.
We use nitrogen flooding to control the dross buildup inside the pump housing.

Weston Bye
05-16-2003, 06:10 AM
Yep. What they said. I built a soldering machine, pump and all. Fairly small as we had to do just 2 solder joints. Pump was made of stainless and immersed in an ordinary solder pot. Parts were placed in bottomless fixtures around the edge of a small index table driven by a geneva mechanism. As each part came into position a DC motor turned the pump so squirt a fountain of solder onto the bottom of the board to make the 2 joints. Dross buildup was a major problem in the pump passages and my design was hard to service. The maintenance techs hated it so I wound up doing the dirty work. (Picture engineer in white shirt working on machine) We eventually replaced the machine, but not before we ran a half a milion parts on it.

05-16-2003, 09:12 AM
Running the wave intermittently is dirtier than running it all the time. The first "spout up" carries up all the accumulated surface dross up before it washes over the sides of the wave.

The wave as it runs is self-cleaning, as long as stuff isn't sunk in the pot where the inlet is. So you probably should have started the wave prior to the part getting there, and then dipped the part into it.

05-16-2003, 10:45 AM
What OSO described is correct, as well as others. I was given a wave machine when a company when out of business. I didn't want the machine so much a the solder, it was high in silver and tin. Which makes for great cast bullets. Throw in a few wheel weights and got a really great alloy for casting.

05-16-2003, 10:52 AM
Thanks for the reply guys. Is there anything that you guys don't know? You have fullfilled my curiosity.

BTW, I won't be participating on this board for a while. I'm off with my family on a long over due vacation. Take care and may the machine gods be on your side.



[This message has been edited by Rotate (edited 05-16-2003).]

Weston Bye
05-16-2003, 12:24 PM
Now that you describe it, the dross accumulation makes perfect sense. I should have used two flow speeds. Low flow to keep the solder flowing through the system, high flow to apply solder to the part. Could have done it too, even with the relay controls I was using. Well, live and learn. Thanks Oso, I may have to do this again.