Making ALK Univ Crossovers From Kit - a couple of Qs.

[nola]

1st - I want to thank Mr Al K. for shipping the kit about a month ahead of what I expected.

I am more than 1/2 way thru. Not everything went according to his nice directions. The soldering tip was usually nasty. The glue gun often gave 1 tiny bead. Etc.

I think I tinned the multistrand "Litz" inductor ends properly. Had a terrible time removing the red coating. The soldering iron kept getting sso nasty. So I have 1 or 2 "funky" tips. The rest I cleaned off with a Harbor Freight equiv of a Dremmel tool with a coarse tip. Not pretty, but seemed ok. A few of the wire tips were less red than others.

However, some the wires had lots of excess length from the coil area to where I solderd the tips.

So 2 Qs:

if I messed up on cleaning off 1 or 2 of each of the 6-8 strands in the inductor wire (Solen .2 and .3 mF) is that a big problem?

Is the "excess"ok to leave as the wire is not coiled now? (It would be a real pain to cut, de-insulate the tips, and re solder.)

I can add pics if you folks want.

Thx

[WMcD]

Having some extra lenght is not going to hurt. And if a few of the strands are not quite clean that is probably not going to hurt either.

I can't speak to Al K's components but I do "feel your pain" about soldering stranded wire which come with enamel. Generally this comes from making Heathkits decades ago. No one has the skill to do a good job the first time, yet our beloved projects ARE our first efforts.

The good news is that remarkably sloppy looking stuff can be electrically okay. But that is not always true.

If you have the time and there is extra wire length, I'd start again.

The power tool was way overkill. I'd fan out the stands over a finger and then use 320 or 400 sandpaper to buff off the ename on one side, and then the other. Then twist them and apply solder before hooking them around a terminal. You should be able to get a shiny surface of solder on them.

Soldering is another skill which take some experience. None the less, the second time you try, you're getting way farther up the learning curve.

Wm McD

[J.4knee]

Even if your solder iron tips are grunky as all get out from stripping the litz wire coating, cleaning them should be simple and not require a Dremmel. Simply heat the iron to solder melt temp and thermal shock it (use a wet sponge to do this while the iron is hot press it into the wet sponge and drag it to remove residue). In a worst case scenario just use a little steel wool to clean off any really stubborn residue. I would avoid the use of a dremmel to clean your tips. Once you've removed the grunky stuff simply add small amount of flux to the tip while it is hot and apply solder to re-tin the tip leave an excess small amount of solder on the tip and let it cool to room temp to store it. When you want to use the tip again attach it to the iron/pencil heat it, shock it to clean off the excess solder and you are ready to go.

[tigerwoodKhorns]

I used a razor blade to scrape off the coating Spread the out and scrape them, it comes off relatively easy.

And don't feel bad, I tink that I put my first one together without scraping the stuff off first and had to go back and re-do it.

[Al Klappenberger]

Nola,

Getting the coating off the ends of the Litz wire is the hardest part of building my networks. It's not hard but it takes practice! It IS quite important to get the coating off every strand of the wire. All the strands must make contact at both ends. There should be no need to scrape. The soldering iron will do the job completely. You need to clean the tip of the iron after each wire end you strip. You can do that with a wet spunge or paper towell. I used to do it with my finger with a single flick. These days, since I do it so much, I use a dual rotating brush device (HAKKO FT-700) designed for that purpose.

The inductors have leads that are a lot longer than needed. I suggest that you practice using the extra length. Try stripping one lead and if it doesn't look right, cut off what you did and try again. My kit gives you 4 Litz inductors. that's at least 8 chances practice! The trick is to start at the very tip of the strands, where the copper is showing right at the ends where the wire was cut. As soon as the solder drop forms completely around the end of the wire turn the iron flat against the wire, on the side and "drag" the solder drop up the wire as you feed solder to the "drop" off the spool. It should take about 5 seconds to drag the drop about 1/2 inch. The striped end should look like any other tinned stranded wire when you are done. There will be some burnt "crud" left, but it will scrape off with you finger nail and will casue no harm. It will float away when you solder the connection to the terminal.

Al k.

[mark1101]

Another helpful hint. I use GE silicone instead of hot glue on the caps. I also use it to fasten the inductors, but I also use tie wraps through the board for the inductors. With tie wraps and silicone, the inductors can't move at all. Works great. Holds tightly, and components can be removed off the board with a sharp shop knife and reused in another project. I have built many networks with GE silicone. Never an issue.

[nola]

Thanx for the replies

At least I don't feel like a @#$%%^> now. BTW the Dremmel type tool kit was just a few dollars on sale at Harbor Freight. I had poor luck with small sandpaper sheets and the soldering iron.

Is there a way to test the integrity of the components soldered onto the board? Maybe testing the volts or ohms across the inductor or a soldered portion of the inductor / components would let me know that the electrical connection is within spec - but I don't know what values are to be expected via my multimeter, especially on partially or wholly soldered portions of the network. I have 1.5v and 9v batteries. I tested my homemade Audioquest intereconnects this way (volts, 9v battery) and heritage spkr components (ohms) this way.

I am around the step for figure 31 now. Most of the caps are in. The resistor and last 3 solders for the caps are not done yet. None of the transformer solders are done. One 1 wire of each inductor is currently soldered. The other is only tinned.

As always, any thoughts appreciated and thanx for the hand holding. That's what makes this place so great (and why I try to answer some Qs too - however much of a noob I am).

NOLA (whoo-wheee is it hot in the South now)

[Al Klappenberger]

Nola,

The inductors would have to be tested for "Q" to determine if all the strands were making connection. That requires a rather expensive RLC meter or impedance bridge. DC resistance could tell but would require a lot more expensive instrument than a simple muitimeter. It would require the LCR meter again. If the leads to the inductor look completely tinned, it should be right.

BTW: I dislike the hot glue too. I just need the glue to harden right away. The silicon glue takes too long! I really hate the "spider webs" that hot glue generates. Nobody makes a good quality small hot-melt gun. They are all dime-store junk! The only good ones I have found use the large glue sticks.

AL K.

[greg928gts]

BTW: I dislike the hot glue too. I just need the glue to harden right away. The silicon glue takes too long! I really hate the "spider webs" that hot glue generates. Nobody makes a good quality small hot-melt gun. They are all dime-store junk! The only good ones I have found use the large glue sticks.

I wonder if there's an epoxy that would work for this? The twin caps could be glued up ahead of time, and with a little planning, they could be glued to the boards and left to dry for a few minutes before working on them. I might try that next time.

Although I don't really mind the hot glue that much. My biggest problem with it is the durability during shipping.

Greg

[Al Klappenberger]

I am not well versed on modern glue types. Maybe there is some glue that will harden in just a few minutes. If there is, I don't know of it, other then "super glue" maybe. I also glue parts down to keep them in place during shipping. I usually use "Liquid nails" in addition to the cable ties to hold large inductors down. I do this under the woofer inductors of the Universal networks I build. Hot glue is not very strong and often will break loose when used under larger value caps, like 33 uF or larger Solen FastCaps. I have had cable ties break as well. Keeping things from breaking in shipping is mostly the quality of packing though. If two things touch each other inside the box, or move around, they will be damaged no matter how they are built!

Al K.

[djk]

I use GOOP.

Use like contact cement and in 5 minutes stick the parts together, about half strength right away, it will fully cure overnight.

[Guest David H]

Keeping things from breaking in shipping is mostly the quality of packing though.

I call this UPS proofing, a good way to protect the crossovers during shipping is to wrap them tightly, and mutitiple directions with shrink wrap.

[Blvdre]

There are also 5-minute epoxies that harden very quickly. I know it's called 5-minute, but you know how that goes.

[djk]

GOOP is better than silicone or epoxy, and it costs less too.

http://www.eclecticproducts.com/all_purpose.htm

[Al Klappenberger]

I'm going to look for "Goop" the next time I need another tube of "Liquid nails". It should work for the large inductors even if it's too slow curing for the caps.

My packing trick is to stuff Wal-Mart plastic bags with peanuts to form pillows that I stuff around everyting after wraping them with bubble wrap. I have also found that FedEx ground is more careful than UPS. Martinelli used to ship the Trachorns to me by UPS. The box would come in with holes in the sides an peanuts falling out every time. Now he is using FedEx ground. The box is virtually perfect every time. I have never lost anything by FedEx. Once in a while a cable tie will bust, but that's about it. On the few ocasions when networks are returned to me they get busted about half the time becasue they are not packed properly no matter which carrier delivers them.

Al K.

[greg928gts]

Keeping things from breaking in shipping is mostly the quality of packing though.

I call this UPS proofing, a good way to protect the crossovers during shipping is to wrap them tightly, and mutitiple directions with shrink wrap.

+1

I've recently discovered how valuable shrink wrap can be when packing things. Bubble wrap something and then shrink wrap it - amazing.

For caps, I was thinking of the 5-minute epoxy that comes in the dual tubes.

How long does it take Goop to set up?

Liquid nails would be very durable, but it takes a day for it to set up, so you'd have to mount everything on the board and then come back the next day. Or use some other method of attachment in addition to the liquid nails. It's not clear like hot melt glue, so it wouldn't look as neat showing between caps or under them.

Greg

[PrestonTom]

Regarding the adhesives .....

If you use silicone in a speaker box or with electronics, then I would suggest that you shy away from the formulations that have a vinegar smell.

[Al Klappenberger]

About the earlier question of making sure all the strands of the Litz wire are making connections I just did a little experiment. I am building a set of "Universal" networks right now. I intentionally unwound a single strand of the wire from one end of a .30 mHy inductor. I measured the inductance and Q of the coil at 10 KHz using my Stanford Research 720 LCR meter. With one strand hanging the measurement was .308 mHy Q= 40.0. I soldered the missing strand back into the tinned end and measrue the coil again. It came out .3076 mHy Q = 42.6. That says there's no way you could ever tell the difference without the fancy instrument. I would have thought the difference would be larger.

Al k.

[bigrfish]

NOLA says,

"NOLA (whoo-wheee is it hot in the South now)"

Dude, I was down at the quarter for a "Tomato Festival" in I think May or possibly June of 2003 and we nearly melted. A quick dive into the Central Grocery Store saved my life, and I was able to buy some nice vanilla beans in the bargain. I started visiting and frequenting NOLA when my old friend the poet Everette Maddox was holding forth down there. He passed in '89, the victim of his Dylan Thomas artist lifestyle illusions. He believed it was impossible to produce true art without living in complicated and mysteriously self-induced suffering.

In one of his poems he said,

'My life is under the bed with the beer bottles. I will never write another line about anything but love in this town where mist rises from the street after a rain like bosoms heaving'

He would have enjoyed your stereo system. They still have a poetry reading named after him at the Maple Leaf Bar on Oak Street every Sunday at either 3 or 2 pm.

Stay cool,

Chuck/Doc

[nola]

After being in Indy and Toronto for over a week I too almost died when I arrived last Sunday night back in New Orleans. Car thermometer read 104 degrees fahrfegnugen, about 41 degrees centipede. In 10 years here it had never read over a 100 before, unless it was broken. As Rosanne RosanaDana, once said......."It's aways something".

Just finished making them. I am making some pics smaller in kb size. I will then edit them in PowerPoint and add a few more Qs in a new posting.

I did not follow all of Mr Ks directions, but usually tried. I connected the 7.5 uF cap directly ino the terminal strip. Moving the Hovland was easy. As Mr. K said, the cheap hot glue gun sucked and the cap easily pryed off. When reglued, I had better luck. Took 2 of the small glue sticks....oy vey.....

Because I almost destroyed an autotransformer by melting it a bit while desoldering a capacitor on a network (while doing recaps a few weeks ago), I purposely tried not to solder these wires. Instead I used extra disconnects to hold the wires in place. I only soldered 1 set of wires to the AT. Bought extra disconnects for attaching the wires to the AT. Shall we say that some of the "attachments" are more creative than others.

I had a bad time with poorly designed 14g Philips speaker wire. Yes you can screw up even spkr wire insulation. So most of these connection had to be redone with some 14G "Primary wire" $5.00 for 17 ft at Home Depot (larger strand size, looks like for home or car electrical use).

All in all, took 5 nights at a few hours per night. For those of you with teenage kids that are not klutzy, this would make a great father-son, mother-daughter project.

One of the engineers at the hospital said Mr. Ks price for the kit was extremely fair given the couple of things he looked up. You see, I dropped solder on one of the inductors and couldn't scrape it all off and I had an almost oopsie with another inductor. So I wanted to know how much a new one would cost, just in case I shorted the loops on 1 (.2 mH) and broke a wire on the other (1.3 mH).

I did test all 6 inductors such as I could. All read .6-.8 ohms across and all read the 9v battery as about 9v. So at least 1 of the litz wires is ok per inductor.

As always, the folks on the forum are super. I again wish to thank Mr. K. Pics will follow in a new thread.