Drag Soldering a 0.5 mm Pitch SMD Connector

[@nikofpv]

In my previous job I was used to solder a lot of this kind of connectors components, I personnaly started to apply just the right quantity of tin on board, uniformaly spread. After that next step was to mechanicaly soldering the connector to insure no displacement during legs soldering, each legs can have a light mechanical tension on reasonable quantity of tin you would have been put previously, this increased the final result quality. I personnaly used way less flux because it can be spread in connector itself when heated and results to a random electrical conductivity with the flex cable. Finally I avoided to pass multiple times on same place with soldering iron, flux is highly effective in first pass but lose its effect when re-heated. We clearly see that your first pass is very clean, but the second goes wrong with a lot of shortcuts (1:06 cut scene ^^) You'd better cleanup and reapply fresh flux in case of first pass failure. Don't get me wrong I don't criticize your work result is finally really clean, I just wanted to share my old personnal experience on this subject.

[@jessihawkins9116]

please learn to spell and edit your comment thanks 👍

[@tvoovm7254]

​@@jessihawkins9116*Please.

[@TheRomanceOfMachines]

My word, you make it look so easy.

[@MG-kw1kb]

Here's an easier & faster tip to ensure that each point is connected to the ribbon connector. After checking that you haven't created any bridges between the lines, take a piece of wire and temporarily create a bridge on the ribbon connector, now firmly press your multimeter's one lead to that temporary Bridge - - and the other lead can be touched to each of the numbered spots quickly and easily and with continuity selected on your multimeter you will hear the beep just by touching each spot for a split second so basically you can then just drag the second multimeter lead over the numbered contact points and if there's a spot without a beep you know that there is an incomplete circuit.

[@GadgetReboot]

yeah that does sound like it’s a lot faster and less hassle. Thanks!

[@giuliobuccini208]

Or, if you have to solder many of this, just prepare another similar board with all of the pins shorted. Then simply plug his ribbon into the one you have to test.

[@giuliobuccini208]

I use the same tecnique, but I simply apply a tiny blob of silicone on the two pads to hold the connector in place. After 24 hours you can then solder the pins. (Use only alkoxy-based silicone to not damage copper.)

[@yoyopei3793]

Successfully solder the little connector! Thanks a lot!

[@RepairsMX]

there are many kinds of connectors that are sometimes a headache to solder hehe. plus do it in a with air conditioner in the room.

[@mestari33]

Very good job! I have to do the same! Thanks.

[@vkdem]

Thank you.

[@Tore_Lund]

How come that every time I try drag soldering, it is a disaster?? I use the ordinary cheap liquid flux, but I presume it is incompability of lead free reflow solder on the board and the leaded solder I'm using, that makes it flow badly creating bridges all over the place?

[@GadgetReboot]

I don’t think the flux is any more or less compatible with lead or lead free solder but definitely leaded solder is going to be easier to work with so that’s good to use. I think the gel flux though is much easier to work with because the liquid just kind of runs off because it’s already flat to the board and if you add more it just spreads out but the gel piles up and as you keep heating it and dragging the iron, there’s a continuous supply Of great quantity of flux and it keeps everything from bridging. I just found it easier to work with so I would try that. It also takes a lot of practice I messed up a lot of connecters first.

[@Tore_Lund]

The ordinary cheap flux pen I'm using is usually very effective, but connectors are of course soldered on professionally made PCBs and I think It is the solder that is incompatible. It is like the two solders form an alloy that is matte, rough and mash potato like = it doesn't really flow. So I think what I have to do is to completely remove the factory solder on the pads with wick and then re-tin them with leaded solder, before I attempt to solder anything to them. I'm soldering a SODIMM connector and it has been a hassle: The pads were nicely flow soldered from the factory, so I thought, just clean the PCB with alcohol and use the tinned pads! Big mistake. I have essentially had to remove the solder again with solder wick and resolder all 200 pins, with all the burnt flux and bridges resulting from that!! So far this single connector has taken me two days to fix. and I still need to test it before applying power!

[@liamyoung6959]

Why doesn't it all bridge when you bring the iron across all the pins?

[@devincress5258]

Flux

[@mrdhksan]

Hi. What kind of equipment or setup do use (if any) for magnifying the component you are soldering?

[@GadgetReboot]

I am soon hoping to set up a microscope for soldering but for now I just do it without anything and if I am recording the video I just try to zoom in as much as I can.

[@MG-kw1kb]

If you're just needing to magnify the piece in order to see your process (not magnifying to record the job) then I find that regular "reader spectacles" (usually sold at most pharmacies etc.) They work quite nicely to just slightly enlarge those tiny parts of a project that you need to see... Or if you need to magnify it even more, use those "Reader Spectacles" PLUS a common magnifying glass. The combination of the 2 lenses make a Massive difference. If you want to record your work, you can take a regular webcam & If you unscrew it's lens a little bit, you'll be able to close-up focus on the tiniest components. That is essentially what a digital microscope is ~ a normal webcam with it's lens adjusted. (No need to buy a specialised digital microscope)

[@13thChip]

I have a similiar connector but all the pin legs are bridged due to soler. Despite using a solder wick, I am unable to remove all the solder from shorting the pins. What is my best way to resolve this mess? Any suggestion would be helpful. Thank you for this wonderful video.

[@rupert274]

I used a jumbo solder sucker and it worked for me. If using wick, make sure to add flux if it doesn't have flux on it from the manufacturer.

[@TMS5100]

I hate soldering 0.5mm pitch FFC connectors so much.

[@giuliobuccini208]

I wonder if solder paste could be a better tecnique. I mean, less frustrating... nobody tried?

[@TMS5100]

@@giuliobuccini208 i tried, all you get is solder bridge hell. drag soldering is also very unreliable and results in many bridges as you can see in this video. the most reliable i've found is to tin the hell out of the pads, drown everything in flux, and then heat the pads while pushing the part down.

[@giuliobuccini208]

@@TMS5100 Very intriguing technique. I have to try it!

[@GnuReligion]

Am curious how you held the connector in place, as you applied that critical first tacking glob. Recently, I use liquid flux as a kind of glue ... it sticks hard when it dries. Have also used Kapton tape, and (rock) hard resin for the same purpose. 0.5mm QFP48s drive me nuts, getting them aligned.

[@GadgetReboot]

The flux paste was acting like a jig holding the connecter in place when I put the first layer on the pad and then positioned the connecter straight on the pins. Then I applied the thicker glob on top of the pins and that held it down from the bottom and the top of the pins at the same time and I guess between that and surface tension as the flux became liquid and also maybe adding that by the time the far end of the connecter had all melted flux, maybe the first couple of pins were already soldered down so there was always something holding the connector. That was my second attempt. My first attempt was to try holding the connecter in place and soldering one of those bigger mechanical tabs on the side but then all the pins were floating above the footprint because the connecter was too high off the board so this way at least the connecter pins would pivot down to the pads and would be in contact.

[@Shamino0]

I haven't tried this myself yet, but after watching a soldering video over on EEVBlog, it seems that his technique is to manually solder one pin (tin the board, then reflow it to connect it) in order to hold the entire connector in place. Then drag across the rest of the pins to complete the job.

[@egeltje68]

Perfect info..... Top... 😉 👍

[@brunofporto]

Great video, thank you very much!

[@tommyoles946]

Where can I find these ribbon connectors ? And I have 2 of those tiny traces gone... Any help would be great !!

[@GadgetReboot]

If you search for example on eBay for FFC or FPC connectors, that’s where you find them. Flat flex cable or flexible printed circuit. www.ebay.ca/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311.R1.TR2.TRC0.A0.H0.Xffc+fpc.TRS0&_nkw=ffc%2Ffpc+connector&_sacat=0 If you have a connector footprint on the circuitboard were a couple of the traces are ripped away, I recently fixed something like that with a micro USB connector that was starting to rip away from a board and had no pad for two of the connector pins so I had to get the thinnest wire I could and try to use a lot of flux to keep things from bridging and just use the soldering iron and heat up the connector pin itself while it’s full of flux, using an iron with solder on the tip and then getting ready to try to put the wire in position on the pin and hold it and hope everything makes a connection straight on without bridging. It can take many tries but using the flux helps keep things clean and using a copper solder wick braid braid to remove solder helps give multiple attempts at a clean work piece. Of course one of the main tricks is not to keep the iron there for more than two or three seconds so damage is avoided. Then I had to solder the other end of the wire directly onto the other component at the other end of the broken trace which in my case was a nearby surface mount capacitor. But if the other end of the trace is not visible because it disappears into the board or something, sometimes I have to use a sharp hobby knife to scrape away some of the solder mask on the broken trace to expose the copper and then just try to solder the wire onto there the same as onto the connector. Create my own footprint.

[@Shamino0]

DigiKey sells these connectors. The problem there is that you're drinking from the firehose - a search will find hundreds of connectors so yo need to know exactly what you want. Also, some brands/models can only be purchased in bulk, and you probably don't need a thousand of them, so you need to look really carefully when placing your order.

[@AnNguyen-hn5gq]

Thanks!

[@GadgetReboot]

thank you!

[@Naked_Snake]

At 0:00 What are the two grey boxes at the bottom? Are those conductive or just visual indications to show where to attach the connector?

[@GadgetReboot]

conductive but just used to solder the connector tabs for mechanical support

[@Naked_Snake]

@@GadgetReboot Ah gotcha makes sense, thanks for replying so quickly! I broke the connector for my laptop touchpad but when I just press the ribbon connector on the bare solder joints it wasn't working. Thought it had something to do with the connector tabs.

[@HDgaming345]

Hi I need to know the female connector name. One end goes into this connector in the video and the other end of cable goes into a vertical female header thing. I don't know the name could you please tell

[@稻米宁]

Nice video，very useful for me！

[@electronic7979]

Useful video 👍

[@Steven-e7c]

Hi. What's the name of this type of board? I'm needing to extend four 68pin FFC cables for an LG signage monitor. The cables are EAD64926601. I'm trying to extend by an additional 6ft.

[@GadgetReboot]

Those types of breakout boards and adapters can be found on ebay and aliexpress like these: www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20210318060653&SearchText=ffc+pcb

[@StreetArtillery]

Im about to end my nintendo 3ds whole career. Broken zif connector replacement challenge. But first i will buy the tools from Va-Chai-Chai-China. Wish me luck yall

[@DaGleese]

And how did it go?

[@jamesbucek2534]

I have a connector that needs to be soldered back to its spot on a circuit board. It looks like a drag solder job smiler to what you did. I want to show you a pic of it and tell me if it can in fact be done. Please contact me

[@Xiryum]

nice

[@andresbudihardja]

how to do it with 88i6745-TFJ1?

[@dofrint2027]

It's an fpc connector

[@giuliobuccini208]

It's a PITA to solder, whatever you name it... 😂