If you are hand soldering think about off setting the holes in the pads so that you do every other one from the opposite side. I also make them a little longer. This isn’t an ‘inline’ example but it should get the idea across.
Thank you, it’s not visible on the 3D representation, but I moved, for the diode in line, an external drill on the left and the other on the right to minimize the risk of over-welding between the pads, I hope this help.
How many of these LED’s do you need to solder?
Is it hand assembly, or automated?
With components like these it is a very big advantage to have plated through holes.
Without the through hole plating you need a “round” solder fillet between the LED pins and the PCB, which easily accomodates short circuits.
But if you have plated through holes, you do not need any round solder fillet on the outside of the PCB. If you only fill the “barrel” hole in the PCB it is enough.
You may also want to think about just spacing the holes further apart in a single line.
If you then cut the length of the pins under a 45 degree angle, each pin has a slightly different length and you can insert the pins one-by-one. (Start with the longest, then push the led aside untill the 2nd longest fits, then push harder to fit the 4th pin, etc).
That part suffers from the same problem as TO-92 transistors, and similar thru-hole packages based on 50-mil (1.27mm) pitch. If you are working with 6 mil (0.15mm) minimum feature size - a typical constraint for a board fabricator’s “standard” product - there simply isn’t enough space between the leads! The lead-to-lead spacing must accommodate:
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The lead’s mounting hole (0.9mm/35 mils - whether or not it’s plated),
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Plus two annular rings (0.15mm/6 mils each - and could be more),
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Plus minimum copper-to-copper spacing (0.15mm/6 mils)
It helps if you reduce the hole size to 0.8mm/32 mils, or even 0.75mm/30 mils if you have a high tolerance for risky behavior. (The smaller holes can be a problem for insertion equipment, especially if the lead dimensions tend toward the large side of their tolerance band.) Elongated pads, and offset drills also help but there’s a limit to how much help they can give. That’s why TO-92 parts are often produced with “formed” leads - either splayed out to a wider spacing, or staggered front-to-back, as previously illustrated by @hermit.
Dale
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I have thirty soldering LEDs per circuit, manually, the idea of a 45 ° cut does not seem to me a solution or I did not grasp your tip.
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