From Brian Willoughby Sent Fri, Jun 29th 2018, 01:53
From Brian Willoughby Sent Fri, Jun 29th 2018, 01:53
It=E2=80=99s a bit of a Catch-22. You have to heat up the pads to = desolder them, but heating up the pads can separate them from the board. = On top of that, these vintage synths were made as cheaply as possible, = so they=E2=80=99re more likely to suffer a copper pad separating from = the board. The challenge is to develop the skills enough to where you can move = fast. Only heat the pads enough to melt the solder, then suck it out = thoroughly. You might have to do that a couple of times. Having a clean board probably helps the iron conduct heat quickly and = safely. Resin/rosin can vastly improve this. When people say to add a = fresh dab of solder, I believe it is mostly the resin from the new = solder that helps things. However, the molten solder does conduct heat = to the old solder really well. I have never liked solder wick. Because it=E2=80=99s slow, you end up = adding heat to these fragile old boards for much longer, and that = increases the risk. The challenge with solder sucker is to have one with a solid vacuum. I = tried a heated solder pump, but its O-rings got old and it didn=E2=80=99t = produce much vacuum. In other words, it sucked and sucking. A good = Weller solder pump does a better job even though it requires heat from a = separate iron. If you align the solder pump correctly, it will evacuate even = plated-through holes. Nothing will save you if you have a ground plane on a through-hole pin. = Those are impossible to do by hand, and mostly likely require a rework = station to apply heat to the whole board. Some lifted pads can be repaired, but that=E2=80=99s yet another skill = that you need to develop before you start working on a masterpiece. Brian On Jun 27, 2018, at 9:59 AM, A. Horton <xxxxxx.xxxxxx@xxxxx.xxx> wrote: > How do you avoid damaging them? >=20 > On Wed, Jun 27, 2018 at 12:38 PM Kenny Balys <xxxxx@xxxxxxxx.xxx> = wrote: >>=20 >> Thats a really good point about the circuit boards. >>=20 >> They damage far too easily so its really not an ideal first timer = job. >>=20 >> On Jun 27, 2018, at 10:36 AM, A. Horton <xxxxxx.xxxxxx@xxxxx.xxx> = wrote: >>> Do you have any tips or guides for how to desolder and replace the = old >>> slider? It's my first real repair like this. >>> On Wed, Jun 27, 2018 at 11:32 AM DJ Maytag <xxxxxxxx@xxxxxxxx.xxx> = wrote: >>>>=20 >>>> +1 on Syntaur, but make sure to also get replacement slider caps at = the >>>> same time. My original caps don=E2=80=99t stay on the new sliders = very well. I=E2=80=99m >>>> sure there=E2=80=99s an easy solution to that though. >>>>=20 >>>> Anyway, I bought a full set last fall and finally got around to = replacing >>>> all of the sliders and pots a few weeks ago. It=E2=80=99s also a = VERY good idea >>>> to replace the power inlet and power switch while you are at it. I = think >>>> there was another part or two I replaced beyond Syntaur=E2=80=99s = 101 Service >>>> Kit. >>>>=20 >>>> As an improvement, to its sound, Tubbetec recommends adding an = extra >>>> ground wire from the D/A chip to the power inlet ground. It adds a = TON of >>>> noise, and adding an extra heavy ground wire reduces the noise = floor >>>> significantly. >>>>=20 >>>> On Jun 27, 2018, at 9:54 AM, A. Horton <xxxxxx.xxxxxx@xxxxx.xxx> = wrote: >>>>> I'm finally getting into servicing my own gear - where's the best = place >>>>> to pick vintage spare parts like this? >>>>=20 >=20 >=20