Pcb coating and Resistors?

kb0jjn

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I am wondering if there is a coating I can put on my board before soldering to prevent shorting. I have read somewhere about some kind of coating but I think the final answer was "not for a repair." I was thinking something like a Sharpie marker to coat the exposed traces.
Also I bought some resistors, with a credit, from Digi Key and they look like 1/8 watt resistors. Are the two resistors in the pic the same?
 

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I am wondering if there is a coating I can put on my board before soldering to prevent shorting.
I can't imagine why you'd need to do this if you're just replacing a part. Sure, there are plenty of substances you could use for insulation but a picture would be needed to understand the situation.

Also I bought some resistors, with a credit, from Digi Key and they look like 1/8 watt resistors. Are the two resistors in the pic the same?
No. Here's a color code guide: http://www.dannyg.com/examples/res2/resistor.htm

The first one looks like brown-black-red (1kohm 5%). The second looks like brown-grey-orange (18kohm %) but it's tough to tell from the photo. They're also different size so they're probably different wattage. It looks like you have two very different parts.
 
The resistor came from the bag in the pic...

here I will try to post a pic about the trace problem.

The problem is when I de soldered the sockets the traces became exposed. The coating on them melted and now when I solder the new sockets in the pins/solder sometimes sticks to the trace. When I try to remove this the trace pulls from the board.
 

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That's enough of a gap that ordinarily you'd be fine. Put a finer tip on your iron, use less solder, use thinner flux-core solder, and approach from the outside. Sure as suggested in other posts you could cover the area in nail polish as insulation but I don't think that's necessary based on the photos.

If that trace has delaminated from the board it's probably not long for this world. Be prepared that you may need to replace the trace with a jumper wire, soon.
 
I did finally pull a trace...After 2 days of desoldering 2 cpu boards. The first pic is the pulled trace to NMI line to pin 17 @ 4M going to pin 19 of 2L running under top half of 3L.
I am going to RS in Easton today to buy some solder and buss wire to repair this.

I want to sell the boards I do get working and would like to coat the final product. I want these to be reliable and that is why I put the time and effort into the renue kit. I would like something that is close to original as possible as these are the orginal boards.
 
I am wondering if there is a coating I can put on my board before soldering to prevent shorting. I have read somewhere about some kind of coating but I think the final answer was "not for a repair." I was thinking something like a Sharpie marker to coat the exposed traces.
Also I bought some resistors, with a credit, from Digi Key and they look like 1/8 watt resistors. Are the two resistors in the pic the same?

Note the "S" in the CFS part number. 'Carbon Film, Small form factor'.
Avoid these for replacing resistor of same size. You could have used a CFS in half watt size to replace an existing quarter watt resistor. But not a CFS in qtr watt size to replace a full size quarter watt resistor. If heat took care of the original quarter watt resistor than heat will more quickly take care of the CFS-1/4.

For trace coating - use an overcoat pen. We often use these for touch up of scraped solder mask. Not cheap, though. Check Mouser, part number CW3300G.
 
Note the "S" in the CFS part number. 'Carbon Film, Small form factor'.
Avoid these for replacing resistor of same size. You could have used a CFS in half watt size to replace an existing quarter watt resistor. But not a CFS in qtr watt size to replace a full size quarter watt resistor. If heat took care of the original quarter watt resistor than heat will more quickly take care of the CFS-1/4.

For trace coating - use an overcoat pen. We often use these for touch up of scraped solder mask. Not cheap, though. Check Mouser, part number CW3300G.

Thank you very much.
This helps me understand the size diffrence. The resistor (R62) broke when I was prying up the cheap plastic ic socket so it really did not fail.

I really did not like what I got. I was going to use these as a sub. for the resistor packs that Digi Key did not have. I bought the Galaga renue kit instead.
 
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