Re: Re-Capping a Mac LCII (Soldering Issues)
Use pure alcohol to clean the rosin flux off of the board. q-tips help. don't use acid flux. ALSO, check out the desolding stations on Amazon - if you have a couple hundred $ to spare. On 10/06/2013 11:16 PM, Hardware Mack wrote: it's messy, corrosive and with these small surfaces um no, its not I don't think it's needed its more important when you are trying to clean up the pads, especially when they are all corroded up / nasty. To each is own.. i have a production environment here, I recap mac boards just about every day now. On Oct 6, 2013, at 11:05 PM, Dylan McDermond wrote: On Oct 6, 2013, at 8:02 PM, Hardware Mack wrote: i have a fan, but the whole corner gets all smoky from the flux. the best bet is to use flux / solder wick / iron and get those pads nice and new looking. I prefer not to use any flux at all. It's messy, corrosive and with these small surfaces I don't think it's needed. I just use silver bearing solder. - Dylan -- -- - You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to vintage-macs@googlegroups.com To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to vintage-macs+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out. -- -- - You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to vintage-macs@googlegroups.com To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to vintage-macs+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
RE: Re-Capping a Mac LCII (Soldering Issues)
LOL...somehow that doesn't surprise me. Heaven forbid a few kids work with a small amount of lead in a reasonable manner. I'm definitely not using lead-free...pretty sure I crossed paths with that trying to repair a newer computer motherboard...what a pain. I got some Radio Shack silver bearing solder - 62/36/2. It seems to work fine compared to other solder I've used. Per a guide or two I found online for replacing the surface mount capacitors, I flowed a little solder onto the pads, then laid the capacitor on top of the small mound of solder...then I used a small flat-tip screwdriver to hold it down so it didn't move, as well as to force it down onto the pad as the solder melted on one side. Then the theory is, after that side sinks in, repeat on the other side. In reality, half the time the screwdriver moves it off of perfect center as soon as I touch it...then when I finally do get it pretty much where I want it, the solder doesn't seem to want to re-melt and drop the capacitor down into it...leaving me worried I'm going to fry the poor capacitor with the excess heat. Just doesn't seem to be quite enough pad or capacitor lead sticking out the sides to get the heat to it. When I do finally get one side in, then the other side doesn't want to budge at all...possibly because the other side is too firm? I've tried adding some flux, but it still doesn't seem to help much...though it did do wonders for removing the legs of the old capacitors. How do you guys install the new ones? Is there a way I should be doing it other than mounding up a bit and trying to melt it into place? I'm using a YiHua 936 soldering station...from what I see (found a Youtube review/comparison), a pretty decent clone of the Hakko 936. It's still new to me, pretty much started using it for this project. Seems to be doing ok...though I seem to default to cranking the heat all the way up to get it working like I would like. In the past, I've been using a 25 or 30w off-brand pencil iron. Figured it was time for something better and more controlled. It has a very nice fine point to it...though heat transfer at the very tip seems hit or miss. I've got a couple of circuit boards to try assembling...will probably try starting one of those this evening with it and see how it does for through-hole stuff...whilst waiting on further advice from all the surface-mount experts here... :-) Thanks everyone! Wesley -Original Message- The last time I saw that kind of problem it was a club of students trying to build a robot. Someone told them they had to use lead free solder. Don't try that! 60/40 tin lead solder works well with some rosin based flux which is likely inside of your hollow core solder. The lead free stuff requires a weak acid flux that has to be carefully cleaned off and requires another 15 degrees C to flow.. -- -- - You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to vintage-macs@googlegroups.com To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to vintage-macs+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: Re-Capping a Mac LCII (Soldering Issues)
Are you using a conical tip or a chisel tip? Any chance you could take a couple photos of the joints you're having trouble with? There are a couple things I'd suggest based on what you've described; the first is to not put too much solder on the pad initially. You want it slightly more than just tinned, but not much - that will help with getting the cap level. It will wick with less than you think. As far tip heating goes, how much solder do you have on the tip? Carrying a little more on the tip sometimes helps heat transfer to be more reliable, especially for reflowing. That will also flow into the joint a bit so you're not relying solely on the pad blob. Tip shape will make a difference here as well, chisel usually transfer heat better. Keep using the flux, it does help for reflowing even though it's hard to tell sometimes. On Mon, Oct 7, 2013 at 8:40 AM, Wesley Furr wrote: > LOL...somehow that doesn't surprise me. Heaven forbid a few kids work with > a small amount of lead in a reasonable manner. > > I'm definitely not using lead-free...pretty sure I crossed paths with that > trying to repair a newer computer motherboard...what a pain. I got some > Radio Shack silver bearing solder - 62/36/2. It seems to work fine > compared > to other solder I've used. > > Per a guide or two I found online for replacing the surface mount > capacitors, I flowed a little solder onto the pads, then laid the capacitor > on top of the small mound of solder...then I used a small flat-tip > screwdriver to hold it down so it didn't move, as well as to force it down > onto the pad as the solder melted on one side. Then the theory is, after > that side sinks in, repeat on the other side. In reality, half the time > the > screwdriver moves it off of perfect center as soon as I touch it...then > when > I finally do get it pretty much where I want it, the solder doesn't seem to > want to re-melt and drop the capacitor down into it...leaving me worried > I'm > going to fry the poor capacitor with the excess heat. Just doesn't seem to > be quite enough pad or capacitor lead sticking out the sides to get the > heat > to it. When I do finally get one side in, then the other side doesn't want > to budge at all...possibly because the other side is too firm? I've tried > adding some flux, but it still doesn't seem to help much...though it did do > wonders for removing the legs of the old capacitors. How do you guys > install the new ones? Is there a way I should be doing it other than > mounding up a bit and trying to melt it into place? > > I'm using a YiHua 936 soldering station...from what I see (found a Youtube > review/comparison), a pretty decent clone of the Hakko 936. It's still new > to me, pretty much started using it for this project. Seems to be doing > ok...though I seem to default to cranking the heat all the way up to get it > working like I would like. In the past, I've been using a 25 or 30w > off-brand pencil iron. Figured it was time for something better and more > controlled. It has a very nice fine point to it...though heat transfer at > the very tip seems hit or miss. I've got a couple of circuit boards to try > assembling...will probably try starting one of those this evening with it > and see how it does for through-hole stuff...whilst waiting on further > advice from all the surface-mount experts here... :-) > > Thanks everyone! > > Wesley > > > -Original Message- > > The last time I saw that kind of problem it was a club of students trying > to > build a robot. Someone told them they had to use lead free solder. > > Don't try that! 60/40 tin lead solder works well with some rosin based > flux > which is likely inside of your hollow core solder. The lead free stuff > requires a weak acid flux that has to be carefully cleaned off and requires > another 15 degrees C to flow.. > > > -- > -- > - > You received this message because you are a member of the Vintage Macs > group. > The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > To post to this group, send email to vintage-macs@googlegroups.com > To leave this group, send email to > vintage-macs+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/vintage-macs > > Support for older Macs: http://lowendmac.com/services/ > --- > You received this message because you are subscribed to the Google Groups > "Vintage Macs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to vintage-macs+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > -- -- - You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email
Re: Re-Capping a Mac LCII (Soldering Issues)
On Monday, October 7, 2013 7:40:58 AM UTC-5, Wesley wrote: > > Per a guide or two I found online for replacing the surface mount > capacitors, I flowed a little solder onto the pads, then laid the > capacitor > on top of the small mound of solder...then I used a small flat-tip > screwdriver to hold it down so it didn't move, as well as to force it down > onto the pad as the solder melted on one side. When I do finally get one side in, then the other side doesn't want > to budge at all...possibly because the other side is too firm? I've tried > adding some flux, but it still doesn't seem to help much...though it did > do > wonders for removing the legs of the old capacitors. > Do not tin both pads. Tin only one pad. This is what I recommend in all the places where I've written instructions for this. As you have observed, if you tin both pads, one you get one terminal soldered down, the other terminal cannot move. So, the trick is to tin one pad and not the other. Then solder the terminal on the tinned side so that the terminal of the cap sinks down to the pad in the puddle of solder. Then solder the other terminal and pad together using pencil and solder. It also sounds like you may be using a little too much solder, because you shouldn't be having that much trouble getting the solder to melt. Jeff Walther -- -- - You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to vintage-macs@googlegroups.com To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to vintage-macs+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
