Snipping old caps

soop · 04/13/2018, 02:13 PM

I'm watching GametechUS on youtube (on a Friday night, go me) and he snips the caps with short nosed snippers, and it actually seems to do a decent job. What's the consensus of this technique? Any downsides?

crazydean · 04/13/2018, 03:37 PM

As opposed to what? De-soldering?

soop · 04/13/2018, 03:51 PM

Yeah

crazydean · 04/13/2018, 04:03 PM

Personally, I prefer it because you don't have de-solder both legs of the cap simultaneously. Also, you're not adding any heat into a possibly damaged cap.

The only downside I see is if you get sloppy and cut into the cap, causing electrolytic fluid to spill out. If you don't have enough room to get snips between the board and the cap, and try to cut it anyway, that could cause a rupture in your cap.

Cordelay · 04/13/2018, 04:05 PM

I know next to nothing about soldering/desoldering, but I tend to think that the more cautious you can be with old hardware, the better.

Voultar talks in one of his videos about the risks of snipping a corroded cap and taking the pad with it (might be this one, but can't be certain https://youtu.be/oe0DvzKMNe4). He uses a hot air station instead, but maybe you could desolder and lift them one leg at a time...

Best of luck!!!

crazydean · 04/13/2018, 04:25 PM

Wait, are you talking about SMD caps? If so, then you are definitely going to ruin a pad. I thought we were talking about radial.

If a component is soldered to a pad, always heat the solder. If it has legs, feel free to snip away.

Cordelay · 04/13/2018, 04:42 PM

I assumed Soop was talking about SMD caps, since I've seen various GameTechUS where he does that, and maybe if you know how to do it without applying to much force upwards it works well...
(I won't try it with my pc engine gt though

)

MNKyDeth · 04/13/2018, 05:02 PM

Its really trial and error to see what works best for you.

I have had caps that were so dried out that once I put a hot air station to the cap to heat the solder for removal the cap exploded and I didn't have the hot air station on it for more then 2-3 seconds.

Some solder corrosion is so bad that it's nearly impossible to heat and melt it before cap popping and other damage happens to the traces from all the heat.

Honestly, imo... Remove the caps carefully any way that is within your capability to fix if something should go wrong. And remember.... Wash the entire boards thoroughly before putting new caps back on. And remove the op-amps in the audio area so you clean under them. Test the traces through the board before putting caps back on can help to find bad traces with less stuff in your way for testing.

soop · 04/13/2018, 05:19 PM

Yeah, I'm talking about the og surface mount electrolytic caps. But tbh, I'm still scared to do it myself

Cordelay · 04/13/2018, 06:20 PM

This guy does a damn fine job repairing broken pads in this video

Hope you don't need it though!

soop · 04/14/2018, 09:47 AM

Quote from: Cordelay on 04/13/2018, 06:20 PMThis guy does a damn fine job repairing broken pads in this video
Hope you don't need it though!

Dude, this guy is hella good!! One of the best solderers I've seen, I think I'll subscribe

ToyMachine78 · 04/14/2018, 10:58 AM

Quote from: soop on 04/14/2018, 09:47 AM
Quote from: Cordelay on 04/13/2018, 06:20 PMThis guy does a damn fine job repairing broken pads in this video
https://youtu.be/vx50YtEC2S8

Hope you don't need it though!
Dude, this guy is hella good!! One of the best solderers I've seen, I think I'll subscribe

The guy looks like he has a pretty expensive setup. Having the proper tools makes any job easier.

Keith Courage · 04/18/2018, 08:49 PM

I like to grab and twist the old caps off using a pair of small pliers.

Ergot_Cholera · 04/27/2018, 05:33 PM

I usually remove SMD electrolytic caps by wiggling them back and forth until they break from the board and leave their legs behind on the pads.

soop · 04/27/2018, 05:53 PM

I literally don't know. Like... It can't be worth fucking up a boxed GT over the wrong decision... And Keith is someone I hugely respect as being way more talented than me. Yet I've seen others who say in bold capitals DO NOT DO THIS. Agghhh

Keith Courage · 04/27/2018, 07:12 PM

Out of all the methods I've tried, the twisting method just works best for me. Not saying it's the only way to go about it. I find that twisting them off generally works best especially if the cap had been leaking on the board. Anytime I've tried heating up and removing a cap that was a leaker it would end up lifting a pad.

NightWolve · 04/27/2018, 09:17 PM

Quote from: soop on 04/13/2018, 02:13 PMI'm watching GametechUS on youtube (on a Friday night, go me) and he snips the caps with short nosed snippers, and it actually seems to do a decent job. What's the consensus of this technique? Any downsides?

I never trusted his technique, I saw the same video you're talking about. I think I'd rather have 2 solder irons to heat up both legs of pesky, leaky surface mount capacitors when it comes to their removal.

After removal, I'm conflicted about replacement between low ESR Panasonic caps and Steve's idea of switching to dry tantalum caps so they never leak again and you gain other possible pros/cons.

soop · 04/28/2018, 08:27 AM

Quote from: NightWolve on 04/27/2018, 09:17 PM
Quote from: soop on 04/13/2018, 02:13 PMI'm watching GametechUS on youtube (on a Friday night, go me) and he snips the caps with short nosed snippers, and it actually seems to do a decent job. What's the consensus of this technique? Any downsides?
I never trusted his technique, I saw the same video you're talking about. I think I'd rather have 2 solder irons to heat up both legs of pesky, leaky surface mount capacitors when it comes to their removal.

After removal, I'm conflicted about replacement between low ESR Panasonic caps and Steve's idea of switching to dry tantalum caps so they never leak again and you gain other possible pros/cons.

I was thinking that as well actually. What are the cons of using tantalum caps?

Cordelay · 04/28/2018, 08:31 AM

Well, I did it. I tried both twisting and snipping smd electros on a couple of old pcbs and I must have been twisting wrong, either too fast or too slow, because I lifted several pads... So I snipped very carefully my way through the PC Engine GT and my newly adquired PC Engine Duo.
It was scary for a newbie, but I managed to change all 73 caps succesfully! Now I just need the Duo's AV cable to arrive to try and adjust the CD pots.
Had to use the stock conical tip included on the TS100 soldering iron (it's been more than a month since I ordered a couple of flat and beveled tips) and at first I couldn't get good soldrr joints, but I managed applying the heat parallel to the pads.
Thanks a lot for the kind advices Keith, Soop et al.!!!

Any tuts for CD pots adjusting and PCE GT Lion battery mod?

NightWolve · 04/28/2018, 01:46 PM

Quote from: soop on 04/28/2018, 08:27 AMI was thinking that as well actually. What are the cons of using tantalum caps?

From what I remember they're less forgiving to voltage spikes, but you can just pay more for models with higher breakdown voltages. If max breakdown is 16V, doesn't hurt to buy a bigger one at 32V with same capacitance value. There are other details but we need an EE pro to answer.

One useful pro-tip I learned from Steve is if you at least target the 4 power-related capacitors in a Turbo Express, you can get rid of that annoying hum sound when a game is paused, that you hear very clearly when using headphones. Thought that was interesting, I remember that hum from early on after playing my TE.

Thing is, Steve does the whole PCB using tantalums, but he knows what he's doing! For us "hacks" with solder irons, we're probably better off staying in our lanes and sticking with regular caps, preferably not be cheap and pay more for low-ESR Panasonic caps which are much better for the PCB!

If you care about your NEC hardware working for as long as possible, you'll pay for premium Panasonic instead of cheap Chinese as I almost did.

Quote from: Cordelay on 04/28/2018, 08:31 AMAny tuts for CD pots adjusting and PCE GT Lion battery mod?

Any tips you mean for those 3 potentiometers related to the CD laser ??

Yeah actually, but do you have an oscilloscope ? Cause then you can adjust them like a pro to the best possible setting instead of going by "gut" where if a burned CD-R is working that's "good enough."

Le Steve has a video somewhere demonstrating his technique which turbokon also learned and made his own video if I recall correctly. We have the regular guide if you search the forum to adjust them without an oscilloscope.

I would wait before messing with them, test CD games first. For sure if you change the laser or CD-Rs stop working, you'll have to try your luck but I'm not sure you need adjustment after a full capacitor replacement job.

Cordelay · 04/28/2018, 04:45 PM

I don't have oscilloscope, but I might buy one on Amazon and return it afterwards, can't afford to buy one just yet. Is the Steve's tutorial here? I'll look for it when I get home later. Thanks for the tip

crazydean · 04/28/2018, 11:09 PM

Quote from: Cordelay on 04/28/2018, 04:45 PMI don't have oscilloscope, but I might buy one on Amazon and return it afterwards, can't afford to buy one just yet. Is the Steve's tutorial here? I'll look for it when I get home later. Thanks for the tip

Remind me not to sell to you.

Cordelay · 04/29/2018, 05:41 AM

Quote from: NightWolve on 04/28/2018, 01:46 PMAny tips you mean for those 3 potentiometers related to the CD laser ??

Yeah actually, but do you have an oscilloscope ? Cause then you can adjust them like a pro to the best possible setting instead of going by "gut" where if a burned CD-R is working that's "good enough."

Le Steve has a video somewhere demonstrating his technique which turbokon also learned and made his own video if I recall correctly. We have the regular guide if you search the forum to adjust them without an oscilloscope.

I would wait before messing with them, test CD games first. For sure if you change the laser or CD-Rs stop working, you'll have to try your luck but I'm not sure you need adjustment after a full capacitor replacement job.

I couldn't find any of the videos you mentioned, but read the tutorial on the tuts section yesterday and TheSteve and others kept mentioning the importance of marking the starting point before adjusting any of the five pots. The problem here is that the guy who sold the Turbo Duo to me told me he had tried to adjust them to no luck, so the damage might already be done (also the console smelled at first like cat piss, it was disgusting

).

I've seen some members have written their ohms readings but, man, I don't even know how to read the pots with the multimeter... such a newbie...

Are the ABC points the three legs of the pot? I think I'll better ask these questions there

Quote from: crazydean on 04/28/2018, 11:09 PMRemind me not to sell to you.

K, will do!

SamIAm · 04/29/2018, 11:25 AM

I recently recapped a Super Famicom and encountered a few surface-mount electrolytics. Twisting them - not tilting them side to side or pulling them or any motion other than as if turning a screw - seemed to me to put the least stress on the board. They came off with tremendous ease and the board seemed to be able to hand the torque with no trouble. YMMV with Duos or whatever else.

If you're feeling like being a big-spender to get good capacitors, try to identify which caps are doing power decoupling and replace them with Panasonic OS-CONs. They look a bit like electrolytics, but they're solid-polymer based. They have lower ESR/better frequency response than tantalums, come in fairly high capacitance values, and have the side benefit of not using blood minerals (no offense to anyone who uses tantalums; they're in most modern electronics anyway). In positions other than decoupling, their super-low ESR can actually screw things up a bit, so do watch out for that.

soop · 04/29/2018, 11:54 AM

Quote from: SamIAm on 04/29/2018, 11:25 AMI recently recapped a Super Famicom and encountered a few surface-mount electrolytics. Twisting them - not tilting them side to side or pulling them or any motion other than as if turning a screw - seemed to me to put the least stress on the board. They came off with tremendous ease and the board seemed to be able to hand the torque with no trouble. YMMV with Duos or whatever else.

If you're feeling like being a big-spender to get good capacitors, try to identify which caps are doing power decoupling and replace them with Panasonic OS-CONs. They look a bit like electrolytics, but they're solid-polymer based. They have lower ESR/better frequency response than tantalums, come in fairly high capacitance values, and have the side benefit of not using blood minerals (no offense to anyone who uses tantalums; they're in most modern electronics anyway). In positions other than decoupling, their super-low ESR can actually screw things up a bit, so do watch out for that.

I wish I could figure that all out

NightWolve · 05/02/2018, 02:01 AM

Quote from: Cordelay on 04/29/2018, 05:41 AMI couldn't find any of the videos you mentioned, but read the tutorial on the tuts section yesterday and TheSteve and others kept mentioning the importance of marking the starting point before adjusting any of the five pots.

Yeah, I have some screenshots to make for you with thesteve, and the videos are on Facebook, both on steve's account somewhere (Steven Hanley) and turbokon's. If I find them when I get a chance, I'll link 'em back up here.

Cordelay · 05/02/2018, 05:51 AM

Man, thanks a lot, I've tried looking for either Turbokon or TheSteve facebook profiles, but couldn't find any of them (there are a couple of Steven Hanley's but they were either private or not likely to be TheSteve himself) so if you post the video/s when you find the time it'll be much appreciated.

On another matter, I read your xseed facebook post and I couldn't believe it. Having worked for years on the music bussiness (and left it willingly!) I can relate to all the greedy-backstabbing-corporative-upstarts-schemers theme.

At least it feels fine to have supported NIS buying Ys 8 for the Vita on release. I was on the fence on buying Origins for the Vita on Play Asia, but I can only find publisher info about the PC version (which seems to be indeed published by xseed). Do you think the English translation on the Vita Multi Asia physical release will be one of the projects you were involved with?

Sorry if I asked too much or it is a sensitive question.

And thanks for your help!!!

Vimtoman · 05/09/2018, 01:22 PM

Quote from: Keith Courage on 04/18/2018, 08:49 PMI like to grab and twist the old caps off using a pair of small pliers.

Thats what I do also . Saves the pads.

PunkCryborg · 05/09/2018, 01:47 PM

I snip the caps with some small and very sharp hobby side cutters right above the bottom ring at the base of the cap. What's left is the bottom ring that lifts off and leaves just the leg stub and pad which I de-solder after cleaning the PCB and electrolytic shit that leaked out Takes 2 or 3 snips and it's very quick and safe. I haven't lifted a single pad since I started doing it like this and can de-cap a board very quickly.

MobiusStripTech · 05/09/2018, 04:05 PM

I always remove with hot air. Fresh solder to all the pads first. I never lift pads using this method.

soop · 05/09/2018, 05:12 PM

Quote from: MobiusStripTech on 05/09/2018, 04:05 PMI always remove with hot air. Fresh solder to all the pads first. I never lift pads using this method.

See that's exactly what I'm thinking. Have you got a youtube channel by any chance?

NightWolve · 05/09/2018, 06:32 PM

Might as well learn the hot air gun method so you can replace a chip/CPU some day like a pro. My SNES needs one of the 32KB x 8-bit SRAM (D43256AGU-10L) chips replaced some time when I get around to it. The pins are far enough to try with a solder iron (a good one!), but it's risky to go one by one...