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Selective moving pot vs fixed pot

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#55369

Selective moving pot vs fixed pot | 3 July, 2008

Looking at the different Selective solder machines. Are there any process considerations with a moving pot versus a fixed pot. What about the angle and peel off on the moving pot?

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#55371

Selective moving pot vs fixed pot | 3 July, 2008

On an ACE KISS machine we could program a drop in Z height to give a peel off angle after the component was soldered. Usually not necessary as the solder at the nozzle is falling away from the lead down the nozzle. If possible, we would program a free area to overtravel to at the end of a row (still at soldering height). Bridging (and dross) was greatly diminished with N2. If N2 quality was poor you would see bridging or icicles begin to form on tighter pitch and/or longer lead length parts.

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#55393

Selective moving pot vs fixed pot | 7 July, 2008

Biggest differnce is tooling. Tooling cost with a fixed pot - no tooling cost with programable "moving"pot.

There are various way to control peel off with a moving pot. Depending on the machine, you can use either the Z axis or the actual pump speed that controls your solder height. We sometimes use both at the same time to avoid solder shorting. But it mostly depends on your design.

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#55417

Selective moving pot vs fixed pot | 8 July, 2008

> Biggest differnce is tooling. Tooling cost with > a fixed pot - no tooling cost with programable > "moving"pot. > > There are various way to control > peel off with a moving pot. Depending on the > machine, you can use either the Z axis or the > actual pump speed that controls your solder > height. We sometimes use both at the same time > to avoid solder shorting. But it mostly depends > on your design.

Chunks, What conditions would you need tooling or fixtures. Can you give examples

Thanks, PCBHELP

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#55419

Selective moving pot vs fixed pot | 8 July, 2008

Most "non-moving pots" are tooled piece of steel with pockets full of solder. At least that's what the marble in my head understands it be (?).

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#55432

Selective moving pot vs fixed pot | 9 July, 2008

Chunks, It sounds like you are referring to the construction of the solder pot. Not sure how that would require additional tooling cost? Thanks PCBHELP

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#55433

Selective moving pot vs fixed pot | 9 July, 2008

I think what Chunks meant is... TOOLING = THOSE POTS

So basically, if some of your SMT or Through-Hole parts move around via a redesign or a respin, you will incur tooling costs (TOOLING is "THOSE LITTLE POTS FULL O' SOLDER.")

When you're researching which direction to go - movable vs. static little pots o' solder, you'll have to consider things like:

1. Product Mix

You'll have to change those little pots in a high mix environment. That's lots of change-over..not to mention, where're ya gonna store all these things. These pots are good, I suppose, if you're building lots of one kind of product, and it's an easy one.

2. Product Volume

See above.

3. Obsolesence

You looking to move existing grandfathered in products and incur tooling cost on these?

4. New Product Frequency

Do you guys introduce lots of new products that have lots of respins, etc.?

I'd say, your best bet would be selective wave pallets if you wanna go in that direction. You can use the existing wave solder machine, the tooling cost is probably the same, etc.

Also, movable pots simulate wave solder better than the static ones. Like Chunk states, if you're a good select soldering programmer with a good attitude, you can fenagle and finesse that select solder nozzle.

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#55434

Selective moving pot vs fixed pot | 9 July, 2008

Out of curiousity... What is the benefit of the selective solder machine that does NOT have a moveable nozzel?

I am curious since this can be accomplished using a wave pallet.

Thanks

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#55438

Selective moving pot vs fixed pot | 9 July, 2008

Some machines have the pot fixed and the board moves around it (typically at an angle like a wavesolder machine), I think Vitronics takes this approach. No tooling is required per se.

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#55453

Selective moving pot vs fixed pot | 10 July, 2008

We have a Vitronics mySelective machine (model 6749, or "the Fat Bastard" as we affectionately call it). It's configurable with various combinations of "select wave" and "multi wave" pots. Ours has one of each. The "select wave" is for the most part a single point wave, though through nozzle selection we can, and do, solder multiple pins at a time. Tooling required would be the appropriate sized nozzles.

The "multi wave" portion consists of a custom plate with nozzles for each device/area to be soldered. The board is lowered onto the plate and all points solder simultaneously. Big time savings, but at a cost- especially if the machine is used for lead free, as is ours. The PB-free plate requires a special coating process which is long lead-time and expensive. A large plate with many nozzles could easily set you back $20K. A SnPb plate would be quicker to get and more reasonably priced. If thruput- especially with many points to be soldered- is your goal, the cost may be palatable to you. Using the selectwave can result in very long processing time, depending on what you're trying to solder.

Board enters the machine on a conveyor and is transported to the soldering station(s) via overhead gantry with a gripper setup. Depending on the size of the board(s) you process, you may require multiple gripper assemblies of different sizes. In some cases you can process without a process carrier but in many cases one is required.

It's definitely not a "no-tooling" approach.

Other machine notes: Head moves in X,Y,Z,U (rotation) and 3 different tilt axes (angle configurable at installation); IR preheater station, with convection option; independent pick-up and put-down stations allow for continuous processing. We purchased a 2nd, external fluxer so we can alternate between OA and no clean fluxes if desired (internal for NC). Programming can be somewhat cumbersome but can be picked up in a reasonable amount of time by a good tech/process eng.

We have no connection with Vitronics other than as a customer of many years as they are our preferred reflow oven supplier. This post is for FYI purposes only, and is not a recommendation for or against buying this machine.

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#55502

Selective moving pot vs fixed pot | 14 July, 2008

> Most "non-moving pots" are tooled piece of steel > with pockets full of solder. At least that's > what the marble in my head understands it be (?).

Our Selective solder machine has a fixed pot with a fountain in the middle of it. The table moves the board to the fountain then down to it. The board holder can be adjusted to hold most boards. But it's not so fast.

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