Experiences with re-reeling / custom reels - how reliable? - Page 1
Forum section: electronics / general

author: gooligumelec
author_rank: Contributor
timestamp: February 16, 2021, 06:31:14 am
content: I'm about to order a manufacturing run for just 100 units for a product I'm intending to (try to!) sell. That means purchasing just 100 of some parts, no more than 400 of any.My CM requires reels, with sufficient (at least 30cm) leader. And he says that he doesn't like Digi-Reels, or especially the custom reels from Element 14. Says that the leader is often poorly connected, just a bit of sticky tape that jams the feeder, or breaks. He recommends his turnkey service, where he orders everything and uses some jellybean parts out of the CM's stock, and that's tempting because any issues become the CM's problem. However it costs a bit more than if I purchase my own reels, and I like the idea of being sure of exactly what's gone onto my boards.Does anyone have any experience, good or bad, with the custom (re-reeled) reels from major distributors such as Digi-Key or Element 14 (/Farnell etc.)?Some of the parts are available at good prices from the manufactures, namely Wurth and TI in this case. Both offer custom reels. Does anyone have any experiences with manufacturer's re-reeling services? Is there any reason to believe that they would be higher quality than Digi-key's efforts? That's assuming that Digi-key etc. really do have badly attached leaders?I'm also aware that it can be more economical to simply order more parts than are needed, instead of attaching a separate leader. Then the first 100 or so get wasted, but for chip resistors or caps, who cares if they get thrown out? Problem is, the various distributors do not guarantee that if you order say 500 parts on cut tape, that it will be a single length that you can re-reel. Might be 5 pieces each of 100, and then it's no good. The Wurth salesman assured me that Wurth can guarantee cut tape in a single length. But am I right to be worried about this if I take the "order extra and waste some" approach with Digi-Key? Their T&C's say yes, I shouldn't assume anything... Just wondering about real world experiences.If I was sure this product would sell, I'd just buy full reels up front and keep them between assembly batches. Not a risk I can take on this first one though, trying to minimise cost while ensuring a successful build....All advice much appreciated!

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: February 16, 2021, 08:46:10 am
content: Based on my experience:Element-14 - horrible especially on plastic black tapes. They even had 2 piece tape in between once! But they provide this service for free, I won't complain.Digikey - spot on most of the time but their wider tape (16mm) re-reel is just bad and almost certain jam my feeder. For $7 per reel, I expect something better.RS - similar to Element-14 and also free.LCSC - provided the re-reel service for their passive components only not long ago at $3 per reel. Not as professional as the above and many times it just break.TI - Similar to Digikey.The key is usually when they load the reel onto the feeder, they have to ensure the component tape itself is being lifted up a bit at the connection point. In any case, this would mean losing 1-2 components usually. Nowadays I bought my own splicing tapes and leader tapes as these are awfully cheap. As long as the connecting tapes is properly applied (use a hard metal ruler to ensure the adhesive is applied throughout the connection point), it is more reliable than the above services.If those 100 could fit into a tray or tube, maybe that will work for them?

author: SMTech
author_rank: Frequent Contributor
timestamp: February 16, 2021, 09:00:00 am
content: Re Reeling from Farnell/RS is often terrible, splicing is supposed to be accurate with the two ends meeting almost spot on and being the same material, instead they seem to use plastic leader for just about everything and its often mounted over the top of the first pocket in the tape with the cover tape extensions slapped on any old how. This obviously does not work.Different SMT feeder designs have different requirements for leader and trailer tape, on our Essemtec feeders I can easily accept no leader at all, although ~3 empty pockets reduces the risk of something snagging right at the beginning when presenting the first part. By contrast a trailer is quite important, as these feeders wind the cover tape round a spool, if you put in a strip that will run out, that cover tape comes loose and winds itself around whatever it fancies, which can cause a different part to end up all over the floor/inside the feeder. A Mydata agilis feeder has a blade that pushes under the cover tape and shoves it to one side, a spliced on bit of leader tape with no attached cover probably doesn't work well here either, and this kind of action is not uncommon (because unwinding cover tape form a spool afterwards is a PITA.The main issue I see with what you are suggesting is the exact quantities, that won't fly with most CMs there needs to be a few spare to cover everything from the multiple exposed pockets in some feeders, damaged tape or parts, losses during handling or placement and indeed the supplier being unable to count. Different CMs will have different requirements here, I prefer at least 10 on all your tiny shrapnel parts and higher on 2mm pitch just because low volumes of that is too fiddly to handle.If you don't trust your supplier to use trustworthy generic jellybean parts, why do you trust them to assemble your product? Let your CM use their own stock of the stuff they have loaded and ready to go, it should save them time and you money. Supply yourself the parts that are expensive difficult to source or you have already.As a small CM I can tell you for instance we have discount structures in place that get us better prices than you from Wurth and for passives, end or one from end column pricing on most passives and semis regardless of volume from the vendors that sell that way.

author: tszaboo
author_rank: Super Contributor
timestamp: February 16, 2021, 09:41:28 am
content: If the assembler offers turnkey, and the qoute is too high for components, there is an easy explanation for that.So you used Würth components, and asked a qoute for it. The same part that is 0.001 dollar for the quote is uploaded to Digikey or Farnell at 0.1 dollar. Your CM didn't bother asking them directly for their price, they just buy it from the distributor and pass the extra cost down to you.if you really care about the price, I would ask for a detailed breakdown for the price, and cherry pick the components, that are a lot more expensive than they should be. Send them only those on reels, let them purchase the rest. 20% of the BOM lines usually give you 80% of the cost.

author: SMTech
author_rank: Frequent Contributor
timestamp: February 16, 2021, 10:02:29 am
content: Quote from: NANDBlog on February 16, 2021, 09:41:28 amWell how much work a CM puts into pricing is up to them. However the Wurth example is poor, anyone who has dealt with them will know their shipping charges and methods often mean their low price is meaningless when they drop ship a single line of a multi-line order from 3 continents and charge you shipping for every single shipment.In our case we put some work into the pricing we ome up with, components get a (small) margin to cover handling, losses, changes in availability and pricing between quote and order etc, and frankly the breakdown is really none of your business for a small one off order, and just leads to a silly negotiations over pennies where we end up making no money. Either you like the total price or you don't, if its way out from where you think it it then you need to ask why, sometimes its because rival quotes have taken a price and ignred the stock/lead time required to get it.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 16, 2021, 10:45:10 am
content: For cheap passives just order enough excess to cover leader/trailer - as long as it's continuous tape and not creased, the CM should be happy with it - they will have hundreds of empty reels if they need it reeled.If it's a part that the CM stocks then use theirs as they will have it on reels already.Considering how long it can take to put kits together it may just be easiest to get the CM to order everything, then any issues with reeling etc. are down to them

author: tszaboo
author_rank: Super Contributor
timestamp: February 16, 2021, 01:33:51 pm
content: Quote from: SMTech on February 16, 2021, 10:02:29 amThat's not my experience with Würth. Although, they have a local office here, maybe that makes a difference. Also he incoterms.Quote from: SMTech on February 16, 2021, 10:02:29 amHaving a margin on the components is fine, and accepted way of doing this.gooligumelec said he is not happy about the price of the CM, there is always room for negotiations. The buyer really has a lot of other options, so he could just walk, I'm actually saying he should put some effort to mend the existing contract so everyone is satisfied.For example, I did the same at another project. Price didn't seem right, I asked for a breakdown. There was two IC that I had a quote from Avnet, which was a lot better. I just talked to the CM and Avnet, so the CM could buy the parts for me at that price. Everyone was happy, took me half an hour work. The CM already had to do the work, because they base the price on that.Or I had CM, that based their pricing on the method of "pulling numbers out of their asses". Every single quote I received from them was ending with three zeros, with one or two EUR difference.

author: SMTech
author_rank: Frequent Contributor
timestamp: February 16, 2021, 02:01:58 pm
content: .. yup, as a customer you should have some idea of the value of your BOM, but you certainly see a few where they pay no attention whatsoever. It certainly doesn't hurt to put target pricing on your BOM lines, at least the ones that might make a difference or where you have agreed contract pricing with the supplier/manufacturer when you designed in their specific product. This lets the CM know if one of their quoted prices is out of kilter for some reason, you certainly see some oddities now and again. Of course the downside is they might just use that number and save themselves the effort, but if they do that there's only so much they want the work.Wurth have local offices in the UK, we used to buy 1000's of those 5mm pitch industrial green terminals as well as all the usual Molex knockoffs etc they churn out, which are offered by the world and his dog. In theory their pricing and their offering is good, but this delivery behavior was a frequent a recurring issue and devalued their offering both by undoing the cost saving and the endless arguing with them about the excess delivery charges. One can only assume this has got worse this year, with the extra Brexit costs unless they have improved their logistics for the UK.

author: jmelson
author_rank: Super Contributor
timestamp: February 16, 2021, 05:03:40 pm
content: Without knowing what specific feeders they use, it is hard to say. I have never used the Digi-Reel service. If they just splice on leader, it may not work at all. I have gotten spliced leaders from Newark, I think, and they were not well done. The crimped-on metal splices for the sprocket holes ABSOLUTELY would not work in our Philips/Yamaha feeders. The holes were about half the normal size.Both the old Philips/Yamaha and the Quad feeders on my new machine will run with essentially no leader on the component tape.So, you only need to splice some old cover tape to the new cover tape and get it threaded. Of course, a contract manufacturer might not want to deal with that much fiddling.Jon

author: gooligumelec
author_rank: Contributor
timestamp: February 16, 2021, 10:45:52 pm
content: Quote from: SMTech on February 16, 2021, 09:00:00 amThanks - that's exactly the type of feedback I was after! Won't go with Farnell (Element14 over here) then...Quote from: SMTech on February 16, 2021, 09:00:00 amSorry, should have been clearer. I understand that 10 or more spare parts is useful. So where I wrote "100 parts", read "110" but the comparison with a reel of 4000 still stands, i.e. I'm still looking at re-reeling.Quote from: SMTech on February 16, 2021, 09:00:00 amYes, that makes sense. Still have the issue of sourcing partial reels for the more expensive parts, but this information has been very useful - thanks!

author: gooligumelec
author_rank: Contributor
timestamp: February 16, 2021, 11:14:34 pm
content: Quote from: NANDBlog on February 16, 2021, 09:41:28 amGood advice, thanks!Quote from: NANDBlog on February 16, 2021, 09:41:28 amJust for kicks I thought I'd test this with the BOM for this product - just the parts that go onto the PCB, not including the PCB itself, or enclosure or cable assembly.So, I have 41 components to be loaded onto the PCB. Just 5 (12%) of those account for 80% of the total cost.But maybe that's unfair, because one of those components is a Bluetooth module that's more than half of the total. Excluding the BLE module, 11 of the remaining 40 components (27.5%) account for 80% of the remaining cost.So yeah, don't sweat the small stuff. Selecting a cheaper regulator or ADC or shielded inductor (in this design) overwhelms a few cents on chip resistors!But then, those more expensive parts are where the magic happens. Engineering is all about trade-offs... Keeps it interesting!

author: gooligumelec
author_rank: Contributor
timestamp: February 16, 2021, 11:22:44 pm
content: Quote from: mikeselectricstuff on February 16, 2021, 10:45:10 amYep, makes sense. The challenge, as I mentioned, is that distributors don't guarantee that cut tape will be continuous.Quote from: mikeselectricstuff on February 16, 2021, 10:45:10 amYes, making it the CM's problem has a lot to be said for it. Lower profit margin, but I get to spend that time inventing the next widget or (ick!) marketing, instead of chasing parts suppliers.

author: gooligumelec
author_rank: Contributor
timestamp: February 16, 2021, 11:32:18 pm
content: Quote from: jmelson on February 16, 2021, 05:03:40 pmEspecially not for a small order from a customer who might not be recurring.This is a CM in Sydney, and labour cost is very much to be avoided here. I've had PCBA for a couple of products done in China before, quite successfully, with them sourcing parts locally in Shenzhen at prices I couldn't complain about. Actually just placed another order with them just a couple of weeks ago. But going local for this new product, which means leaning on the automation as much as possible to keep pricing not too much higher than Chinese assembly.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 17, 2021, 01:24:47 am
content: Quote from: gooligumelec on February 16, 2021, 11:22:44 pmI find it pretty rare that parts don't come on a single piece of tape. Digikey are the only occasional offenders - I think you can spec continuous tape in order notes but I always forget( ignoring RS of course who are just hopeless at packaging)

author: Mangozac
author_rank: Frequent Contributor
timestamp: February 17, 2021, 03:26:46 am
content: For another data point, we get plenty of re-reels from arrow.com (they don't charge for them once you build up plenty of arrow points to be a bronze level customer). Not chip parts (it's rare we order these in anything but a full reel). I haven't noted any issues with them. Digikey we have found to be hit-and-miss.Note that it's common for CMs to not charge for jellybean passives. When they're paying less than 0.1 cent per 10k resistor the cost can be absorbed fairly easily.

author: tszaboo
author_rank: Super Contributor
timestamp: February 17, 2021, 08:44:24 am
content: Quote from: mikeselectricstuff on February 17, 2021, 01:24:47 amI remember ordering some 50 ICs from RS.It arrived in 5 small bags, each with a cut tape of 10 ICs.

author: tszaboo
author_rank: Super Contributor
timestamp: February 17, 2021, 08:49:39 am
content: Quote from: gooligumelec on February 16, 2021, 11:14:34 pmMost project will be like that. There will be a microcontroller, an expensive ADC some connector or a power supply part, that is significantly more expensive than the part you place next to it. If you place an ADC, it will require bunch of analog rails bypassing, and some NP0 or COG part filtering the input, and you place 5-10 times more passive parts around it, that are cheap. A microcontroller is similar.I've rarely seen a board that would be an exception to this.

author: SMTech
author_rank: Frequent Contributor
timestamp: February 17, 2021, 09:50:56 am
content: Quote from: NANDBlog on February 17, 2021, 08:44:24 amThat's pretty minor for them, these days they quite like sending PICs individually wrapped in a weird card/foam wedge with a piece of tape holding it shut. Years ago we used to use lots of INA139s from TI, RS was the UK stockist, we used 4/800 at a time. I kid you not they send them in cut tape, 1 per bag for a SOT25, they showed stock of over 2000 and every single one was already prepped like that. Its not a typical volume part I grant you, even TI happily reels them as standard in 250s but this was not unique and it continues to this day. MBRS340 diodes, 3 times cheaper than elsewhere, bagged in singles, doesn't matter if you tick the production pack radio box, that is what was coming. If you order via your internal contact they do at least tell you, "whoops they come packed like this, do you still want them" ; do it off the website tho' and it really is pot luck.I have at least 4 items this year that have got as far as the SMT line where they have sent completely the wrong thing, they include M3 split washers instead of a 43K 0805 (honestly our own stores must have been sleeping when they put that in the job box), an SO8 driver instead of a SOT-223 Mosfet, QFN device that should have been a 1206 inductor and two different (but related) not exactly cheap diodes instead of some passives. I don't even kn ow how they manage it half the time, quite a lot of the warehouse is robotic.

author: jmelson
author_rank: Super Contributor
timestamp: February 18, 2021, 04:17:11 pm
content: Just to elaborate on my earlier post. My old Philips CSM84 had Yamaha feeders with a sprocket that pulled the tape after the pick-up area. This required you to peel the cover tape and spill about 5 small passives or 1-2 chips. You spliced the cover tape to a piece of old cover tape with masking tape.My new Quad QSA30 machine has the sprocket pushing tape from behind the pick-up area. My scheme with unused tapes is to peel just a tiny bit of the cover tape and then feed it in. When the tape has arrived at the pick-up area, I use tweezers to pluck the cover tape up and make the splice as above. The trick there is to not have the leading edge of the component tape catch in the return track. I'm still figuring out how to deal with this on plastic tapes. If the tape catches in the track, the sprocket drive is strong enough to shred the sprocket hole side of the tape.This is definitely a fiddly task.With tapes that have at least some leader, it is easier to thread the Quad.Jon