Never Again!

I decided to try to rework a digital control board rather than build another one (I have four already). I wanted to drop an OLED in for the programmer, swap out the headers, and the LEDs so they line up with the new case. Long story short, I lost the OSC pad in the main analog header and one of the pads connecting to an LED. Getting the LCD off was a bitch. I’m never doing this again.

I managed to make a jumper from the OSC to ATMega Pin 18 (which will be hidden by the new OLED so that’s fine). Can someone check me on this? I think that’s the only place the OSC pad needs to connect to. I fixed the LED pad too with a bit of wire.

Not worth it man! I would much rather have spent a few hours building a new board than partially destroying an old one. Might try this again if I ever get a Sucking Soldering Station™, but not doing this again without one!

I really need one of those desolder things too. But where do you stop? :slight_smile:

I know. Synintegrator on YouTube has one and he repairs/reworks old synths. I think it’s essential for major desoldering. Anything less is futile, like resistance…

I also got a wonky din Jack at the First shruthi i built. It is the Midi out so no big Problem. It still sucks and i am thinking about trying to remove the LCD and fix it. I was Not brave enough to try it so far. But rosch doing it gives me some new hope.

I’ve tried to unsolder a lcd screen, once, because i had badly soldered the din5 connectors.

I ended up cutting the pin header with a dremmel, which proved to be the best technique in my case. Nonetheless, damage had been done and I had to replace the lcd screen. This was a red lcd screen, man! Fortunately, the control board could be saved…

i did it once and it worked. i can’t remember now if i used desolder wick along the row of pins or just moved the iron at full heat along them (horizontally, with the whole length of the tip touching the pads). and pulling a little on the side i just was. i had to do it several times and be very careful, of course.
brute force but it worked.

Me too. Dremeled it. Bleh.

I tried that Rosch, on both sets of pins. With that many solder points they really need to be clean and wick just didn’t suck up enough solder…I started to worry that I would break the controller board pulling on it. That’s when I broke out the Dremel cutter…

Maybe I’m not patient enough…

it was not what i’d love to do every day. basically you have to pull it up while it’s all hot and fluid then keep it till dry. and start at the other side again.
if you have a spare board or 2 days time to wait for a new one, the parts you’d have to buy again are just a few bucks, so probably not worth it.

bought a hot air pencil from hk for desolder work, heat the pins at 400 degrees, blow solder out of the holes etc. Cheap like borsch, good borsch, not that watery stuff they feed to capybaras, no wonder they get mad and carry those tiny axes. Ooops wrong thread.

Hot air pencil? Can you provide a link please? Sounds cool!

The hair driers are like $200. What does a hot air pencil set you back?

I got an hot air aoyue 908+ rework station, bought for about 120 € on ebay.

It’s loaded with an excellent iron (with an heater from hakko, which is known to be pretty robust) and with an hot air pencil. I’ve been using it quite extensively (as an hobbyist though) for like one year and a half and I’m absolutely delighted about that. The iron gets warm very quickly, so i’m constantly switching it on and off, which is better for keeping your iron tip OK. Actually i think i never had to change the iron tip, which i believe is quite remarkable given the amount of work i’ve done with it.

The hot air pencil allows you to focus on just one or two solder joints, as opposed to an hot air drier which is more indicated if you want to completely remove all the components from an old board you want to salvage.

Good choice, MicMicMan. I chose between this and Lukey-702 in favour of the second due to half price and integrated turbine.
Aoyue 908 is more professional. Lukey-702 has few cons: hot air fan needs temperature calibration and bad solderng iron jack. Anyway this is the perfect solution for $80 :slight_smile:

If I ever build any more of these I’m socketing the LCD. I’ve done it. It look/works fine, and if you use the OLED display instead, it’s about the same height.

Problem solved.

Thanks for the info on the pencil. I will check it out!

How did you do it?

I thought about soldering the pin header to the LCD then removing the black plastic surround, shortening the legs and plugging into something like this:

Obviously keeping the display in place is one challenge :slight_smile:

good idea, 6581punkt.

i was thinking on my next shruthi i`ll use only 2 single pins from the heard for the last and first pin (to keep it in place) and small pieces of wire or cut resistor legs for the other pins to make it more easy to desolder if there is need to do so.

Heh. Never again? I did it twice (not OLED, but I had to remove the LCD for stupid brain reasons).

The first time I ended up cutting the headers through the plastic spacers.
Second time I got lucky and didn’t destroy anything.

But I did find great use from this:

Oddly the same model number as this:

I will post pics of the build as soon as it’s done. It’s coming together nicely but I haven’t done a sound check yet so there’s still a long way to go… need to hook up power, audio, and midi jacks today.

I did the LCD socketing with this female header:

This piece goes into the Shruthi and then a regular male header is soldered into the LCD/OLED. The socket is nice and tight and makes a good solid fit. Trust me the display isn’t going anywhere. It is difficult to unseat it, but NOWHERE NEAR as difficult as unsoldering a header :frowning:

It’s pretty low profile too, but it does raise the display up. For an OLED it’s no big deal because they’re thinner to begin with. But I don’t think it’s a problem either way. I’m going with this method regardless of the display I choose. I have a piece of cardboard under it now to support it and keep it flat. Not sure what I will do permanently (I kind of like the garage-style piece of cardboard personally…). I bet the display would (or could) be dipped slightly forward at an angle, which wouldn’t be such a bad thing. It would make the display easier to see when not directly on top of the device.

Change cases? Change display colors! It’s like the swatch watch of the shruthiverse!

Can anyone post a link to an LCD bezel that will fit the displays we’re working with? I’m guessing a bezel without a window would be better…

Looks like the socket header I linked to.

But you can get separate PCB pins which might work instead of messing around with pin headers. They push in and the splines on the pin hold it in place.