#88

If that’s Kester 44 or similar solder, the flux isn’t intended to be cleaned and will just smear.

Edit: Also note, do NOT use just any “rubbing alcohol” to clean alcohol-solvent flux - ideally it should be ~99%. Less than that and there starts to be enough water content in the alcohol to be potentially problematic - most “rubbing alcohol” is in the 70% range, and that is neither going to do a great job of removing some fluxes but will also leave quite a bit of unevaporated water on the surface for a while. That’s why most people use “IPA” (Isopropyl Alcohol) - that variant usually comes in high purity inexpensively, since it doesn’t cross with the ethanol usually used in rubbing alcohol which must by law be adulterated in order to sell for non-liquour purposes.

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#89

Wow, thanks for this! I have kester 44 and I couldn’t understand why it was making a huge mess when I tried to clean up with IPA.

#90

Miniware is irons are good for travel. The new usb-c ts80p seems to be well received and close to ts100 power specs. There are still some PD related firmware issues, but I can confirm it does run from a usb powerbank. Here is a link to github were the are discussing alternative firmwares for the device.

#91

What does the other side look like?

#92

it depends what the other side looks like. in itself, the lack of visible solder coming through the hole would not concern me.

but i see a lot of evidence of insufficient iron contact / too much solder = potential cold joints. for example D3, R4, etc. the spherical blobs are not good because the solder should be sucked down against the parts / traces. the dull colored spheres are near-certain signs of cold joints. if you were soldering through the other side, i’d guess the solder melted, dripped through the hole, and collected in a droplet without bonding sufficiently to the parts.

i would reflow all the blobby-looking stuff, being sure to make simultaneous contact with the component leg and the pad.

1 Like
#93

@zebra @JaggedNZ here’s what the other side looks like.

IMG_1588
IMG_15883978×2399 1.84 MB
IMG_1589 2
IMG_1589 24032×2704 2.73 MB

So, to me, the joints look pretty good on the side I actually soldered (don’t get me wrong, this thing isn’t winning any beauty contests). Should I remove the blobby solder that leaked through to the other side? Or just heat the leg on that side so that it moves to the pad?

Or not worry about it?

#94

yeah ok, there’s just too much solder on the joints where it has blobbed through. i would clean up the blobs because in the long run they are liable to crack and fall apart, etc.

the joints you circled actually look much better to me. you don’t really want or need solder coming through to the other side, it should pretty much stay in the hole / on the pad. those are a little on the light side but i think that’s better than too heavy.

i’m maybe over-emphasizing this point because the great majority of the DIY photos i’ve seen on the forum are using too much solder, and this is a pretty prime example.

i still think there are some potential cold joints. any time you’re seeing a spherical blob it’s a red flag.

#95

Very good. I’ll do some reflowing this evening. Thanks for the help!

#96

This is a two year old comment but want to add that breathing out while soldering decreases cussing during complicated builds, as well.

2 Likes
#97

does anyone have any tips or tricks for desoldering a potentiometer from a fates board? i cant seem to get all 4 or however many solder points loose at once and i feel like im damaging the board by holding it there so long. the desoldering braid i have is almost completely useless and i havent had much luck with my cheap solder sucker (just the kind that pulls back and then triggers). that worked for a pin header once, but that was kind of a different scenario it seems like

#98

Solder suckers can help, which one are you using… if you don’t have an Engineer SS-02 Solder Sucker, get one and try it… What you really want is an air reflow station to get that thing out…

Or you can try to use a larger iron tip to hold across the 3 pins to heat all 3 up at once and pull it out while they’re hot, it’s tricky but it can be done… I never solder the retaining clips on my pots for just this reason, just fold them over it’s good enough but if those are tacked down too it’s going to be a lot harder.

1 Like
#99

Are you trying to salvage the potentiometer to use again? If not, it’s easiest to cut the part away from the pins, so then you can desolder the pins individually.

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#100

im trying to take one from my old fates board that i fucked up elsewhere and then take off K2 from my current fates board very carefully and put the one i took of the old board onto the new board. im having a lot of jumpy encoder issues with that one

#101

this piece of garbage

image
image679×776 78.8 KB

the ss-02 looks helpful. from what i remember, the reflow stations can be kind of expensive but im sure they’re worth it.

that’s a good tip, i’ll try that next time. wish i knew that before. thank you

#102

I find solder suckers are ok to remove most of the solder but usually won’t get you to the finish line. Do you have flux you can apply before desoldering with the braid? If not, try applying the iron to the braid to the joint and then some solder to that combo with the idea that that will seep through the braid and the braid can then soak up some of the joint solder. The braids are supposed to have flux on them but I find they always need a little help with flux applied to the joint or fresh solder (which is a tricky as obviously that solder will need to wicked away too but that solder will at least provide some flux for the old solder to join to). Ugly business.

Like @DMR mentioned, if you’re going to junk one encoder, definitely cut the encoder away from the soldered bits first.

2 Likes
#103

i got a silicon solder sucker a while ago and it’s a gamechanger. way easier than braid or plastic solder suckers

1 Like
#104

A powered desoldering vacuum like the Hakko FR-301 is the best thing in my experience, but it is also way overkill (and $250-300) if you’re just using it occasionally. If you have a makerspace in your area you could try to see if they have one you could use for a 1-off job.

#105

How hot does your iron get? Big pieces like potentiometers act like heat sinks and it can be difficult to get the solder hot enough to use braid

Getting a variable temperature digital control iron was really big for me, you can do a lot of things so much quicker at the hotter temps

#106

A nice wick in a smaller size,1.5 or 2mm, has always worked well for me. Some nice flux if it’s giving you a hassle. Never found suckers to work on small things.

Depending on what iron you are using, if it is removable I would look for a knife tip. Pressing the edge flat against the wick on the joint spreads out the heat and works really well.

Gootwick
https://store.rossmanngroup.com/ab20-gootwick-cp2015-pink.html

This is only place I’ve found to get small quantities with fast cheap shipping. They have the 1.5mm as well. Useful to stock up. They also sell Amtech flux which is #1 for SMD stuff

Beware of knockoffs on eBay, got some fake Gootwick and it was rough to use! Also theres fake Amtech flux out there :sob::skull:

Good luck!

2 Likes
#107

i guess 900° F/40 W. this one:
https://www.amazon.com/dp/B000AS28UC?ref_=pe_2640190_261118450_302_E_DDE_dt_1

it was a big improvement over my radioshack style piece of shit that was like the type that just has the power cord attached and no stand or heat adjustment. it made soldering go from impossible to very easy, but i think i got some bad solder or maybe my tip was bad for a little because when i soldered the trellis grids together for my diy grid, it was very weak and flaky. i dont think that had anything to do with the iron. i know its not the best option, but any other time it has seemed to work really well

it may not get to an ideal heat though, i have no idea how it compares to other irons. i have never gotten more than a tiny bit of solder stuck to the braid i bought

@alley_cam thanks for the link, i thinki will grab some, but that knife trick may work

@philmaguire i think that is what i need ultimately, thank you

@addamm i have tried that with the braid, but not with flux. i grabbed some paste flux from the hardware store, but i think that’s for like pipes or something. i was looking sort of recently online for a small amount of the liquid flux but im not sure which kind to get exactly

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