Metallurgical Crossover Question

[Skywave-Rider]

Are brass screws good to use in crossovers when fastening coils down to a wooden panel (using nylon zip ties, for example)? Brass is non ferrous, yes?

[Chas]

Brass non-ferrous? In theory, yes. Personally I use either ty-wraps or a glue gun or both, only.

Note that inductors inductively couple, so it's good practice to leave plently of space between them and keep them at right angles from each other.

[Skywave-Rider]

Thanks, Chas.
On the one I recently made I used hot glue only. But I'm thinking for long term that's not good enough. So maybe a combination of hot glue and nylon -- but on a wooden board I guess just drill through for the zip ties. Ideally I want to screw down a nylon strap of some sort directly to the top of the board.

[Chas]

-- but on a wooden board I guess just drill through for the zip ties.

Yup, That's exactly what I do.

[Baron030]

Hi Skywave-Rider

Here is a trick that I use for mounting large caps and coils to 3/8" birch plywood circuit boards with nylon zip ties. First, I drill holes through the board. And then using a sharp knife, I whittle a slot between the holes. So, that the zip ties are recessed flush with the board’s bottom surface. It helps to round the holes bottle edges, so that the zip tie does not have to bend too sharply as it goes through the hole. It will only take a few minutes of whittling and test fitting for the zip ties to lay flush with the bottom of the board.
Pictured below is an example.

Baron030

[Skywave-Rider]

Baron030,
Hey, that looks very neat!
Should I assume it's 3/8" birch plywood circuit boards? I notice the coil is alone on its own board. Do you remount these on a larger board with other components?. Please forgive me, I have no woodworking skills, LOL, feel free to ridicule me..... But I want to steal your technique.

[Zilch]

Zip ties are available with screw-down tabs.

I don't use glue because I know that inductor will one day likely be back on my crossovr cart.

All of my crossover boards mount on standoffs. You'll notice I never show the backs of them here....

[Baron030]

Actually, the coil pictured is currently stuffed inside a card board box.
Unlike Zilch, I haven’t gotten around to building a crossover cart yet…
No question about it, Zilch has been at this a lot longer then I have.
Hell, sometimes I feel like I am just a beginner around here, still learning a lot.
So, I try to share what little knowledge that I have and contribute where I can.

For a while the coil pictured was used as part of LCR series notch filter for smoothing out a peak in my 2012H drivers. And it’s just a little project that I am still currently proto typing. But, I am very close to come up with the best solution for smoothing out the rising response of that driver in my system. But, I now am really digressing here.

Getting back to the circuit board pictured, no special tools were used, just a drill and an X-Acto hobby knife. Remember it is not important what your circuit boards looks like that matters. It is what it sounds like that matters. And once the circuit board goes inside of your project, nobody else is going to see it away, unless you were to post some pictures here.

Baron030

[Skywave-Rider]

Baron030,
Hey, I want to thank you for showing me your work. It's very helpful. And I think your mounting looks good enough to go right on top of the speaker. Best of luck with your response smoothing project.

Zilch,
Thanks again.

[duaneage]

Remember it is not important what your circuit boards looks like that matters. It is what it sounds like that matters. And once the circuit board goes inside of your project, nobody else is going to see it away, unless you were to post some pictures here.

Baron030

I disagree and take a small measure of pride in the etched boards and proper layout of components. Even though they are out of sight I know what they look like

[Baron030]

Wow, Can I retract one of my own quotes!!!

Yes, it does matter what your circuit board looks like.
So, just any old crap will not do!
Follow the old adage, “Any job worth doing is worth doing right.”
So, take some pride in your work.
And take the time to develop a nice clean circuit board layout.

Keep all ferrous metals away from any air core inductors.
And if your crossover uses multiple coils, then be aware of inductor cross-talk and arrange the coils to minimize this inductive effect.

And when you finish your project, then show off a little bit by posting some pictures.
Because,



Baron030

[Skywave-Rider]

Thanks, guys. Well, here's the crossover I did, but I'm about to trash it and start again for this reason:
http://audioheritage.org/vbulletin/s...ad.php?t=18913

I might try to mount the new "M-19 Z" x-over (Z for Zilch) on the existing board until I figure out what the final configuration is going to be. You see I hot glued the coils and caps here. U think wires running between the coils as shown are OK? How about my spacing for the coils themselves?

Eventually, the new one will go on the outside because I'm keeping the original x-over in the cabinet for historical reasons and maybe place the new one, with a cover, on top, or velcroed to the back. First I gotta build and test it. I've never etched a circuit board; I think that's cool. But for this one I'm already overwhelmed, so I'll leave that concept for the next project.