68kMLA Classic Interface
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| Lifted pad... best way to fix? | |
| Posted by: MJ313 on 2015-06-16 18:35:45 Suggestions appreciated on how to fix... my first pad fail (yup I'm new at this recapping thing... good times)  | |
| Posted by: Unknown_K on 2015-06-16 20:04:40 Do you still have the pad stuck to the old capacitor? If so desolder the pad and crazy glue it back on to the motherboard. After the glue has dried use an exacto knife to gently scrape off the coating on the trace then use a solder bridge to join the trace to the pad again. | |
| Posted by: Elfen on 2015-06-16 20:08:31 What type of cap are you using for the recap? Unknown_K's method is the one used the most. But if that fails, solder the cap the board on the remaining cap and then run a wire from the spot where the trace ends to the other side of the cap. | |
| Posted by: raoulduke on 2015-06-16 21:19:27 That's good advice Unknown_K. I have a similar problem on an SE/30. I will try that tomorrow. Elfen I was also recently thinking about that since there's nothing conceptually preventing that as a failsafe - I guess it's just a little sloppy, maybe. Good luck MJ313. | |
| Posted by: archer174 on 2015-06-16 21:59:37 Note that there is a via right next to the pad. I would just solder the capacitor across that via and the remaining pad and call it a day. | |
| Posted by: MJ313 on 2015-06-17 03:30:04 Thanks for all the advice guys- much appreciated! I do still have the pad... it's attached to the old cap. I will go with Unknown_K's suggestion. 🙂 Elfen- I have some panasonic lytics I am using. I recapped a IIsi with them and that works fine, so I am marching onwards. archer174- when you say you would solder the capacitor across the via... what exactly does that mean? Do you mean literally, solder the new cap leg to that via... right to the top of it? Thanks! | |
| Posted by: archer174 on 2015-06-17 11:09:46 Yes, soldering directly to it should be fine. if it's too small then scrape some of the solder mask away using a small flat head screw driver. Perfectionists might cringe, but it's electrically sound. | |
| Posted by: Elfen on 2015-06-17 12:09:28 I keep thinking that the "via" you are stating is the jumper/solder filled grommet to the other side of the board and not the 6522 "VIA" or other chip Mac uses (VIA = Versatile Interface Adapter chip, the 6522 is also used on the 8bit Commodores and Ataris). Archer174 is correct on that. My "problem" is that I use SMD/SMT caps, so soldering to the remaining pad, I have to solder a jumper wire from the other end of the cap to the via. MJ313 - congrats on the IIsi recap. Lets hope you are successful here. BTW - what Mac Board is this? | |
| Posted by: uniserver on 2015-06-17 12:59:48 hey at least the trace is not a frogs hair, as blob likes to call some of them, I would scrape the solder mask off that trace and solder right to it. | |
| Posted by: MJ313 on 2015-06-17 13:12:44 I ain't no perfectionist at this stuff. 🙂 Thanks for all the advice-- I will give it a go tonight and let you know how it goes. This is a Mac II High Resolution video card that came with my dead IIcx. | |
Posted by: trag on 2015-06-17 16:09:34I keep thinking that the "via" you are stating is the jumper/solder filled grommet to the other side of the board and not the 6522 "VIA" or other chip Mac uses (VIA = Versatile Interface Adapter chip, the 6522 is also used on the 8bit Commodores and Ataris).Correct. "vias" are conductor lined holes in the circuit board which electrically connect traces from different layers of the board to each other. A "blind via" is a via which penetrates one or more layers of the circuit board, but not all of the layers of the circuit board. So it does not go all the way through. In this case, there's a nice fat via just a few millimeters north of the lifted pad and a fat trace that once connected the via to the pad. So there are many options for recreating the broken connection. | |
| Posted by: MJ313 on 2015-06-17 18:18:57 I had no super glue for the pad! CA glue, gorilla glue, all kinds of glue but no crazy glue. So plan B went into effect. I scraped off some of the trace... and soldered the cap right to it. lol I have no idea if this works because I have to solder a couple more caps on and I damn near went blind trying to do this and I am shutting down my eyes for the night. I love how it's called a fat trace... cause even though I know it's fat it's still really small to try and carve up 🙂   | |
| Posted by: Elfen on 2015-06-17 18:48:43 Nice recovery! Hope the rest of the card goes well! This the Apple Hi-Res Video card, aka The 8bit Video Card? | |
| Posted by: MJ313 on 2015-06-18 16:54:50 That be the one. And now it works! Thanks everyone here, for the advice. While a small challenge, a challenge for me nonetheless. A good learning experience. Here it is in the IIci .. while the display looks shoddy, it actually looks great in person.  And here's the board.  | |
| Posted by: uniserver on 2015-06-18 17:04:16 :rambo: | |
| Posted by: Elfen on 2015-06-18 17:58:43 That's the one I'm trying to fix. Techknight said that its the rotted traces from one of the caps that leads to RAM. My symptom is that in any Mac II you put the board into, it death Chines. I'm still searching... | |
| Posted by: techknight on 2015-06-18 18:31:25 The cap right above the graphics processor eats the via/traces at that point. That area goes to RAM. Uniserver sent me one with a Mac IIx I got from him, fixed it and works perfectly. | |
| Posted by: Hotdog Zanzibar on 2015-06-25 13:59:32 This is fascinating stuff. I really need to learn how to do this. | |
| Posted by: uniserver on 2015-06-25 14:02:29 when it comes to fixes like the one that he did, you can really appreciate mlcc caps. | |
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