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geekhack Projects => Making Stuff Together! => Topic started by: ajhackerman on Mon, 15 February 2021, 16:50:06

Title: Help on: Desolder, lube and solder an 8x MKII
Post by: ajhackerman on Mon, 15 February 2021, 16:50:06
Hi all,

I've recently got a KBD Fans 8x MII as my first mechanical keyboard. I love the thing but I'm keen to lube the switches for that extra smoothness. I got the board pre-assembled with Gateron Ink v2 yellow and I believe they lubed the stabs only. I reached out to KBD fans directly to ask if it's relatively safe to desolder, lube and resolder back on my switches. To that question they advised against. I'm a relatively handy DIY guy and have watched lots of Taeha Types streams so I have a pretty good idea of what I need to do. I have done bits of soldering in the past but as for lubing switches, well maybe not so much.

I just wanted to reach out to you all for any tips. Is it safe? What is the worst I could do to my board? Is Krytox 205g0 the best lube for my switches. Soldering iron, for a part-timer, any recommendations?

Any help would be highly appreciated.
Cheers,
AJ
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: nevin on Mon, 15 February 2021, 22:13:47
too bad the plate doesn't support switch top removal, then you wouldn't have to desolder at all.
the two in yellow support switch top opening. and alps have always been able to be opened when in plate
[attach=1]
i've changed springs, stems & top housings (everything but bottom housing) in my current board (viterbi) multiple times without ever desoldering a single switch

desoldering, i'd suggest something like this (https://www.amazon.com/Tenma-21-8240-Vacuum-Desoldering-Iron/dp/B008DJRYIG), or a hand solder pump (https://www.amazon.com/Engineer-SS-02-Solder-Sucker/dp/B002MJMXD4) if you're quick

as far as an iron to solder the switches back in, any 30w iron will do. and some 60/40 rosin core solder, DO NOT GET LEAD FREE.
lead free is a lot harder to work with and requires higher temperatures to melt.

do not force the switches out of the pcb, you may lift/tear pads. though you may have to jumper some switches when you solder everything back together even if you are very careful.

if you're really worried about it. get another pcb, plate (that supports switch top opening) and some switches and build yourself another pcb/plate/switch set that you can swap into the case.

lube is up to you. there are different thicknesses and you can apply different amounts for different results. i'd keep the coating light so you don't end up with mushy over lubed switches.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: xudongz on Mon, 15 February 2021, 23:39:12
There's no real risk in desoldering the switches. I'd look up a few desoldering videos and be careful to not heat anything for too long. You don't want to overheat other components (diodes, processors, etc) or accidentally rip them out.

I would also recommend a heated desoldering pump like this (https://www.amazon.com/Velleman-VTDESOL3U-Vacuum-Desoldering-Heater/dp/B07NY9XCJK). It makes desoldering a lot quicker/easier compared to separate soldering iron and desoldering pump.

I'd also make sure that you the lubed switches enough to actually go through this process. Especially if you are new to lubing switches, you may end up doing it inconsistently and need to redo some switches down the road.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: Maledicted on Tue, 16 February 2021, 11:16:13
The worst you can do is lift a pad and/or burn up a trace. Keyboards are pretty forgiving. If this happens, you can usually either (carefully) scrape the solder mask off of the trace and run a jumper wire from the switch leg to the trace, or play around with some scrap wire bridging the undamaged pad to other nearby pads until it registers the correct key press and run a jumper wire from the leg with the damaged/removed pad to that other switch leg/pad.

You want to heat the pad only as much as necessary to melt the solder, and only for long enough to remove it. If you can help it, you don't want to put any stress on the pad (including trying to firmly move the switch leg when there's unmelted solder still bridging it to the pad. It seems to me that lifting a pad is most likely when the pad is hot but the solder isn't quite melted.

As far as tools go, I have only used Chinesium manual pumps. I think one was Radioshack branded. They were a nightmare. I spent almost as much time unclogging them as I did using them once I got the timing right to actually get all of the solder from a single pad in one go. I have heard good things about the higher-end ones by comparison, but have never used one. I have not used the more reasonably-priced combination iron/pumps posted here either. I figured I would be doing a lot of dumb swaps on ancient boards for kicks and giggles, so I jumped straight to one of these bad boys (https://www.amazon.com/s?k=hako+fr-301&ref=nb_sb_noss_2). With this (which have adjustable heat settings), it generally takes me just a few minutes to desolder a whole board if the old solder is decent leaded solder. I like to give it a moment to melt all of the solder on the pad and simultaneously turn on the pump and wiggle the nozzle in a circle. Unless the pump is clogged (yeah, that happens even with these) that usually cleans the whole pad and switch leg of solder in a second or two. If the solder doesn't seem to want to melt, add some fresh leaded solder like mentioned above and/or flux and try again. Some solder OEMs use is pretty terrible.

Once all of the switches are free, the plate should come right off with no force. If you get any resistance at all, double check all of the switch legs to make sure there's no residual solder holding them in place. If your pump isn't that great and/or the original solder isn't that great, you may need to add some quality solder back to the pad/leg and remove it again in order to free it.

You can pull the switches out of the plate with a switch puller like are included in some cap pullers. I usually just pop them out with my thumb once the whole plate is off. When you put all of the switches back into the plate, make sure every single one is oriented exactly as they would sit on the board. Sometimes switches are meant to be installed sideways and it is REALLY easy to bend pins if you try to put the plate back on with any in the wrong orientation. Also make sure that you're not inadvertently using pads not intended for your layout (I can't tell from the product page whether or not the PCB in that kit has solder pads for Windows keys regardless of chosen layout (I would be surprised if it did not).

Once everything looks correct to your eye, you can carefully line the plate up with the PCB and lower all of the switch legs into their corresponding holes. If you meet any resistance, check to make sure that none of the switch legs are bent and bend them back to where they should be and try again. The last thing you want is to rush this and realize halfway through soldering the new switches in that you bent the legs on a few switches. I usually eyeball the legs of every single switch before I even start soldering them into place ... because I have bent some pins in the past without noticing.

When you're ready to start soldering new switches in, you may want to check and see that the big center nub on the switch is relatively center and recessed reasonably well into the hole for it in the plate. You may notice that some of them are not centered and might need to wiggle everything to line it all up reasonably well. If any of the switches seem more shallow than others, I usually just press the PCB into the plate in that area and once they seem relatively flush I'll solder a few switches in that area into place (You don't want to release downward pressure on the PCB until the solder of at least a switch or two is dry again), and repeat for any other areas that look shallow until every switch (soldered or not) looks relatively flush. You obviously don't want to adjust this later when you've already got switches soldered into place near a switch that's sitting somewhat shallowly in the PCB, because then you would be pressing directly against the pads. Only then do I solder all of the rest of the switches into place.

I don't do lube, but I do one heck of a lot of switch swaps, so the above should be helpful. All previous comments are sound advice.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: nevin on Tue, 16 February 2021, 12:18:02
thank you @Maledicted for taking the time to write this wonderfully descriptive how-to, this should be very helpful and covered a lot of good points.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: Maledicted on Tue, 16 February 2021, 13:49:16
thank you @Maledicted for taking the time to write this wonderfully descriptive how-to, this should be very helpful and covered a lot of good points.

You're welcome, and thank you very much for the compliment. I would prefer it if people learned this stuff the easy way rather than the hard way if they can help it.

Maybe somebody knows a good thread that does a deep dive into lubrication that could be linked here?
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: ajhackerman on Tue, 16 February 2021, 14:09:52
Thank you very much @Maledicted. Really appreciate the time and effort put into your replay  :thumb:

I'm on a bit of a budget so I'm probably going to get a hand pump like this (http://"https://www.amazon.co.uk/gp/product/B002MJMXD4?pf_rd_r=0RYT5686P7WJ2DD1YPHJ&pf_rd_p=6e878984-68d5-4fd2-b7b3-7bc79d9c8b60&pd_rd_r=dfb4511e-d8b0-456d-a68a-1f500a5af45c&pd_rd_w=Mtgko&pd_rd_wg=JPTmq&ref_=pd_gw_unk"). I'm probably going to get a relatively cheap iron as well as I'm not planning on doing too many frequent mods. More the part-timer.

I think the lubing part won't be too hard but all in all, I'm excited to have a go. Worst thing I suppose is I'll have to buy a new PCB. Shall keep you posted anyway. Might even do a before and after vid of the sound.

Thanks guys
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: Maledicted on Tue, 16 February 2021, 14:51:40
Thank you very much @Maledicted. Really appreciate the time and effort put into your replay  :thumb:

I'm on a bit of a budget so I'm probably going to get a hand pump like this (http://"https://www.amazon.co.uk/gp/product/B002MJMXD4?pf_rd_r=0RYT5686P7WJ2DD1YPHJ&pf_rd_p=6e878984-68d5-4fd2-b7b3-7bc79d9c8b60&pd_rd_r=dfb4511e-d8b0-456d-a68a-1f500a5af45c&pd_rd_w=Mtgko&pd_rd_wg=JPTmq&ref_=pd_gw_unk"). I'm probably going to get a relatively cheap iron as well as I'm not planning on doing too many frequent mods. More the part-timer.

I think the lubing part won't be too hard but all in all, I'm excited to have a go. Worst thing I suppose is I'll have to buy a new PCB. Shall keep you posted anyway. Might even do a before and after vid of the sound.

Thanks guys

You're welcome, and good luck on your quest. I have heard good things about those Japanese solder suckers. (your link is currently broken, it looks to have an extra http:// and quotation marks on either end of the url). That silicone nozzle will be a godsend over the garbage I was struggling with. Those Teflon nozzles don't get very good suction at all unless they're perfectly perpendicular to the board ... which requires removing the iron from the solder.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: 4sStylZ on Wed, 17 February 2021, 09:47:09
Only risk is to damage pad.
You need to think about the temp. I would recommand a vacuum pump with integrated heater. For 20 buck it's very helpfull, faster, and safer than manual pump with a iron.
The only thing I'll take care of is when legs of the switchs is folded / bendů For example on AEK PCB. I always destroy thoses PCB but I don't care a lot about them. If you have some like that, try to un-bend while heating, for example with a heater tool + twizzer. Never do it when cold : It's the easiest way to lift a pad.

Good luck.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: yui on Wed, 17 February 2021, 10:03:17
if you can set your iron temperature as low as possible while still melting the solder in under 5 seconds, that should allow you to melt the solder fast enough to not melt the switch but also not too hot to overheat the board and lift a pad, it is not super critical but could save you and SO a headache down the line :)
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: suicidal_orange on Fri, 19 February 2021, 10:05:27
could save you and SO a headache down the line :)

(https://cdn.geekhack.org/Smileys/solosmileys/laugh.gif)

If we're preparing for the wost a nice pic of the front side of the PCB side that gets hidden under the plate would be good too.
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: ajhackerman on Thu, 25 February 2021, 13:27:29
Hey all, so it all went down brilliantly! New lubed up 8X feels and sounds great.

I made sure to do a timelapse as well as a before/after so check out the video.


Thank you all for your help and tips  :thumb:
Title: Re: Help on: Desolder, lube and solder an 8x MKII
Post by: nevin on Thu, 25 February 2021, 15:00:50
nice! good job! :thumb: