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If I wanted to have a PCB assembled, would I have to give the manufacturer reels of components, or will pick & place machines also work with cut tape?

I ask because I'm thinking of having a low quantity of boards assembled (100-200), but most reels on Digi-Key have several thousand components or ICs on them.

I would rather buy cut tape with a few hundred ICs (even if it means a higher cost per component), since buying a reels with thousands would be a much higher upfront cost.

Tried Googling this but couldn't find an answer anywhere..

Nate
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4 Answers4

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Some P+P machines can use cut tape, others must use reels. Talk to your assembler to find out what their capabilities are.

You could always get the distributor to re-reel the tape though. They may add a surcharge for this. Look for a "Digi-Reel", "MouseReel", etc. packaging option.

Ignacio Vazquez-Abrams
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As Ignacio points out, cut tape and mini-reel configurations are often acceptable. That said, an assembler I used warned me to be a bit careful with all of these mini-reel options, as they've had some experiences with spliced-together fragments of cut-tape causing feed problems. For things like resistors, where not much money buys you a full reel, just go with the full reel. For more expensive parts, do what you have to do. My preference is to make turnkey arrangements, and let my assembler order through whatever mechanism has been successful for them. If I don't like the quote, I call my assembler and see what can be done.

If you choose to fully or partially kit, your assembler might well demand a part count a certain percentage above the boards to be delivered. Again, talk to your assembler to get this right BEFORE the job is started.

Scott Seidman
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    I've spliced motion picture film, and until I got some practice it was not uncommon for splices to fail. Component tape and reel looks a lot like motion picture film; the reel holes look more like Super-8 reels, but the tape looks more like 8mm. I'm not sure how the actual dimensions compare, though (Super-8 uses 72 frames/foot; 8mm uses 80 frames/foot). – supercat May 28 '14 at 23:11
  • Hmm, I wonder if it was originally designed to share parts with 8mm cine technology.. I second "talk to your assembler", they may even be able to source parts cheaper. – pjc50 Dec 02 '15 at 16:51
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At least on the machines i've seen the reel itself is just there to keep the tape neat. It's not really needed if the ammount of tape in the machine is small.

However the feeders are almost certain to need a lead-in on the cover part of the tape and may also need a lead-in on the base of the tape. They may also need a trailer if they are to successfully use the last few components on the tape. When component manufacturers put their components and reels they include a lead-in and lead-out as a continous part of the tape.

Components bought as "cut tape" will not have a leader or trailer so the assembly house may have to attatch one themselves. If you order a "re-reel" service then the vendor will splice on leaders and trailers for you.

None of the prototype assembly houses i've worked with have expressed any concern about components supplied on cut tape. I have sometimes had the components come back with extra cover tape still attatched.

Splices can break or jam so full manufacturer reels are preffered. My rule of thumb is if I think I will use more than 100 of a low cost component in the forseeable future I get a manufacturers reel. Obviously for high cost components that is not so practical.

I'm not sure I see much point in re-reels. If there has to be a splice i'd rather it be done by the same people who are going to run the components through their machine to avoid the possibility of blame games.

With small components it is very likely that some components will be lost when setting up the real. So allow generous overages.

Peter Green
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You want to have a look at this series from Dave: http://www.eevblog.com/2010/11/15/eevblog-127-pcb-design-for-manufacture-tutorial/

He goes into manufacturing, and, more importantly, the in's and out's of tape, reel, etc. Starts at about 5:30 in the video above.

RJR
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