Burned a capacitor...

[cobblepots]

So I was working on my crossovers yesterday and accidently let the side of the iron touch a capacitor. The black casing melted away slightly (about the size of a pea). The white underneath is visible. Should I be worried? Should I buy a new one? Slightly anoyed at myself about that

[dmalphur]

At worst you shorted a few layers of the capacitor together, reducing the capacitance slightly. Do you have a multimeter to measure the capacitance? If its within 10% or so of the needed value don't worry about it, you'll likely not notice.

-David

[cobblepots]

I don't have a multi-meter available. Best I have at the moment is a lightbulb continuity tester for faulty soldering jobs. It's a very small burn and from what you are saying I'll stick with what I've got. Thanks for the input!

[---k---]

Pictures!

[Mike B]

Test to see if it's shorted. If shorted toss it, it could damage your amp.

[Amphiprion]

I would toss it. It's doubtful you improved it's performance any Even if it passes a continuity test its performance still might not be too good.

[pedroskova]

If it's a metalized polypropylene, don't worry about it.

[cobblepots]

I don't have any pictures with me at the office. Off the top of my head I can't remeber which one it is exactly. It was a Jantzen 5.6 or 3.3mh on the high frequency circuit of the Mini statments network. It's a polypropylene capacitor.

Another question while I'm at it, how far back has everyone been placing the foam lining in the transmission tunnel? Should I place it all the way back against the baffle? I will tune the length to listening tastes but I havn't read anything about where to place the foam in relation to the TB. Thanks for the great advice as always!

The speakers are very close to being finished. I have all the x-overs finished and ready to test and the baffles painted. But with my trip to Japan next week and the extra work I have to do at the office I don't think I'll be making any noise out of them until the first weekend of November. The polishing, grills, and veneer work will come at a later date and I'll probably only do one at a time.

[Jim Holtz]

Another question while I'm at it, how far back has everyone been placing the foam lining in the transmission tunnel? Should I place it all the way back against the baffle? I will tune the length to listening tastes but I havn't read anything about where to place the foam in relation to the TB. Thanks for the great advice as always!

The 1" foam lining in the mid tunnel is a bit touchy in that it must be held back from the back of the W4-1337SA about 2" with the driver end of the foam beveled at a 45 degree angle. I just flush the foam at the back of the speaker.

Following the process I outlined will allow the mid to match the woofers/ribbon and have the mid range clarity the Statements series is known for. If the foam is too close to the back of the mid and isn't beveled, it kills the mids.

HTH

Jim

[cobblepots]

Thanks for your input!

[Luke]

At worst you shorted a few layers of the capacitor together, reducing the capacitance slightly. Do you have a multimeter to measure the capacitance? If its within 10% or so of the needed value don't worry about it, you'll likely not notice.

-David

If he shorted a few layers together it doesn't reduce capacitance slightly. IT's caput!
Just measure resistance with ohmeter and you will see if it's shorted.
If it is shorted the cap is destroyed, whatever dielectric technology.

Luke

[Amphiprion]

Even if it's not shorted, there are a lot of other things that can be wrong with it. I'd toss it.

[cobblepots]

Now it looks like the forum is leaning towards tossing it. Looks like that's what I'll do. It's not worth frying a TB AND buying a new capacitor

[fbov]

Pictures!

I bump Ryan's request because your description may not mean the same thing to us as it does to you. Pictures are also cheaper than new parts ... And I bet responses will be more uniform.

Frank

[cobblepots]

I'm new to the post pictures thing. what res/size does it have to be? How do I post it?

I've been at work 8-5 every day and working on night school from 5-11. Little time for anything during the week...

[Luke]

Now it looks like the forum is leaning towards tossing it. Looks like that's what I'll do. It's not worth frying a TB AND buying a new capacitor

Yeah. And if your cap is shorted and your crossover has a shunt coil, the whole amp will be shorted!
Get rid of this cap as, anyway specs are all changed.

Luke

[---k---]

I'm new to the post pictures thing. what res/size does it have to be? How do I post it?

800x600 jpg less than 100k works well.
In advance posting mode, use the "Manage Attachments" button to upload the picture to the post.

[dmalphur]

Doh. I thought about it more and Luke (and the others) are right. I still doubt that anything is wrong with it, but since you can't test it, I agree that tossing it would be best.

-David