madbeanpedals::forum

Projects => How Do I? Beginner's Paradise. => Topic started by: satchmo1991 on December 04, 2024, 08:52:05 PM

Title: Should I Add Extra Space to What the Datasheet Says?
Post by: satchmo1991 on December 04, 2024, 08:52:05 PM
When a datasheet like the one attached gives "Mounting Hole Details", am I meant to drill the PCB holes with the measurements provided (in the example  2.1 x 1.8mm) or should I add extra room?
Title: Re: Should I Add Extra Space to What the Datasheet Says?
Post by: Aleph Null on December 04, 2024, 10:46:01 PM
There are tolerances to be accounted for: the legs could be an extra 0.2mm larger than the nominal size, also if the holes on the PCB are plated, that will reduce the diameter of the opening. How much wiggle room you need will depend on the manufacturer of the part as well as the PCB. I usually make a hole .25–40mm larger than the nominal size of the leg.
Title: Re: Should I Add Extra Space to What the Datasheet Says?
Post by: madbean on December 04, 2024, 10:46:54 PM
It's rare to find a drill bit that fits exactly for a lot of parts. I usually pick the next size up in millimeters or imperial.
Title: Re: Should I Add Extra Space to What the Datasheet Says?
Post by: satchmo1991 on December 05, 2024, 12:13:45 AM
Quote from: Aleph Null on December 04, 2024, 10:46:01 PMThere are tolerances to be accounted for: the legs could be an extra 0.2mm larger than the nominal size, also if the holes on the PCB are plated, that will reduce the diameter of the opening. How much wiggle room you need will depend on the manufacturer of the part as well as the PCB. I usually make a hole .25–40mm larger than the nominal size of the leg.

It looks like in the image I attached the nominal size of the legs on the side is 2mm wide and the hole they mark out on  the right side is 2.1mm, so it looks like they are already accounting for some tolerances, but I think I'll take your advice and add 0.25mm to be safe.