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Lead Filled Bean Bags for Thru-Hole Wave Solder Components

Tooling Guy

#22711

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 13 December, 2002

I have heard of people using tiny lead-shot filled bags to hold down thru-hole components on circuit boards while running through a wave solder machine on selective solder pallets. How successful has this been? What kind of material is being used for the bags? Has anyone used an alternative material to lead shot..ie stainless steel shot? Going to make up some bags for those lil buggers that you can't get to with a clamping style hold-down.

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#22713

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 14 December, 2002

This is a good idea.

Heck, you could fill the bags with sand, if you wanted.

Like anything else in the shop, bean bags require attention and maintenance. If you don't, eventually the seams on the bags loosen / break and you have to do a "clean-up in Aisle 6".

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MA/NY DDave

#22714

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 14 December, 2002

Hi

To me, something seems wrong with your process.

I have never had to do what you are suggesting, yet I can imagine your difficulty with fluffy (easily floating) components.

I won't give all the technical details, instead I would ask you to have an advisor or a consultant visit your shop since something seems off. Wave Pressure, etc.

YiE, MA/NY DDave

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Randy Villeneuve

#22720

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 16 December, 2002

We trasfered a product in some time ago and they were using erasers to hold down parts. Some parts will move around during wave and some parts just need to be positioned correctly after wave so hold downs are required. I personaly have never used a bag full of shot but it should work as long as you engineer it correctly.

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blnorman

#22722

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 16 December, 2002

We had the same problem and solution with one of our components on one of our lines. Don't know for sure what the "weight" was that they used, but it did solve the problem. Since then the same line is looking a putting an adhesive on the part to hold it in place.

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#22736

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 16 December, 2002

I made a small bean bag from 100% cotton filled with rice, to hold down small resistors that wanted to tilt over solder wave. It worked fairly well as long as I didn't try to take it off the components to soon, as sometimes they would want to stick to the bag and would lift if the solder wasn't set.

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JohnW

#22778

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 18 December, 2002

Soup mix works well for this as well.......

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RDR

#22780

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 18 December, 2002

We sometime use a temporary solder mask to "glue the parts down" if bean bags don't work

Russ

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Mike F

#22782

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 18 December, 2002

I've used rice, too. The trick is to make the bag big enough to hold down the part or parts, but not so big it interferes with the top side heating of the parts around it. I've never actually used lead or steel shot, the heaviest fill material I ever used was BB's. If the bag is too heavy it can cause the board to sag over the wave, which could lead to other problems.

If you need to both align and hold down the parts, you might try a piece of thick FR4 that is machined to match the parts. I've done this for LED's when I worked for a company that made LED based signs.

Mike F

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#22783

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 18 December, 2002

I have used these bean bags for several years now. They work great for holding down odd formed components during the wave process. I use the cotton ESD smock material and cut out what ever size I need. Works Great!.

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Tooling Guy

#22816

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 20 December, 2002

Thanks for all of your input. Soup mix??? well at least i got a chuckle from that one. :) Anyway got some good ideas here and going to try some of them out.

Thanks again.

Tooling Guy

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#22817

Lead Filled Bean Bags for Thru-Hole Wave Solder Components | 20 December, 2002

The rice and soup mix illustrate the point that you probably should NOT be using the lead shot mentioned in the initial post on this thread. The oxide powder on the lead shot could work its way to the surface of the "bag", get onto troops' hands, and could end-up creating health problems for the troops working in the wave soldering area.

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