Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Pin to Hole ratio

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Theo Doucakis

#35656

Pin to Hole ratio | 20 July, 2005

I am looking for some guidance on the proper pin to hole ratio for waved pins.

Theo

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RDR

#35657

Pin to Hole ratio | 20 July, 2005

IPC has this. I cannot remember which one, Here is what I do for a quick reference.

square pin - add .015" to the pin dimension e.g. .025" square pin gets a .040" hole. OR if the pins are large get the max dimension )e.g. a .025" square pin has a dimension of .035" measured corner to corner) add .005 -.010" for the finshed hole diameter.

round pin - add .010" to the diameter.

These numbers will give you your ratio. We usually suggest 60-70% hole to lead ratio

I would consider these as min hole sizes and they can be increased if necessary. Be careful not to make too large or the solder will get pulled back out of the hole during wave process. Holes too small will result in hard to assemble boards and may prevent top side fillets in some cases.

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#35674

Pin to Hole ratio | 20 July, 2005

IPC-2222 - Sectional Design Standard For Printed Board For Organic Printed Boards, Table 9-3 � Plated Through Hole Diameter To Lead Diameter Relationships will give you the standard information you require.

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RDR

#35696

Pin to Hole ratio | 21 July, 2005

Thanks Dave, Now I am going to find out if I am consistent with the IPC.

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Ken

#35702

Pin to Hole ratio | 21 July, 2005

Anyone else disagree with IPC-2222 for min-lead to max hole in the application of ribbon lead connector styles?

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Reflow Oven

Essemtec Fox Compact Automatic Pick and Place