Screaming Circuits: Continuous Strips of Parts

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Continuous Strips of Parts

Not long ago (No Need To Waste Parts), I wrote about the use of tiny cut strips here at Screaming Circuits. That's good information, but only part of the story. (When has anything ever been the whole story???).

IC cut stripThere may be some times when you don't want to buy a reel, full or partial, but still want your parts all in one continuous strip. Everyone wants to use up their odds and ends, but once those are gone, it's easier for you if each part is just in one strip. If you want to save a little money here and can use a longer turn-time, you might want to pick our Short-Run production service. If that's the case, you will need to send in continuous strips. Short-Run requires reels or continuous strip of at least 12" in length.

There are two questions you'll probably ask:

1.    How can I make sure my parts add up to at least 12 inches (305 mm)?

There are two ways to do this. First, if you have some of the parts, measure the length and calculate the number of components per inch. Use that to determine the number of parts you need to get 12 inches.. Make sure to calculate the length based on the quantity you need + 10% (+50%) with 0201 passives).

If you don't have any of the parts already on hand, you can download the datasheet for the component. In the pack, you'll usually be able to 

If the length comes out to less than 12 inches, use the parts per inch to figure out the total you need. If it comes out to 12 inches or more, you're set. Passives commonly come in 2 mm pitch tape or 4 mm pitch tape.

2.    How can I make sure that my supplier sends my parts in continuous strips?

It's not uncommon for DigiKey or Mouser to send 50 parts in 5 different strips of tape. I've even received parts in strips of one. Each part was still in the tape, cut from the reel. They were just cut into strips of one. We can use those in our Full-Proto service, but it's a hassle for you and you can't use them with Short-Run.

Neither distributor has a setting for "continuous strip", however, they do have a place to enter special instructions. Simply state in the special instructions that you need uncut, continuous tape for all parts that come in strips of tape.

Duane Benson
What is the airspeed velocity of an unladen swallow?

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