DIY speaker: braid vs twist vs straight


I'm looking to make some speaker cables between Musical Fidelity amp and B&W Nautilus speakers. Cable lengths are 4 feet and 12 feet. My questions:
1) Could I go with solid core enameled copper magnet wire? Maybe 2 strands of 18 ga for the tweeters? 4 strands for bass? Or should I use a finer wire with more strands like what Belden makes? I can't get any heavier than 18 ga. But I heard solid core was only good for Magnepan planer-type speakers.
2) Should the wires be twisted or braided? How many twists per foot? Or just left straight?
3) Should I use heat shrink tubing to hold the strands tightly together or just slide them through some 1/32" wall teflon tubing?
4) I would like to use bare wire into the binding posts and just use Caig Pro-Gold to treat the copper. Is this the best method?
Thanks
cdc
Dekay, the magnet wire I found has a clear enamel coating. So you're saying I don't need ANY tubing to protection it?

* Would this wire configuration have any funky inductance or capacitance like the Goertz stuff? Probably not, but I want to make sure.
* Should I separate the runs by 1/4" or more? Or can the 4 bi-wire runs be bundled together?
* I found the Radio Shack wire. It too is enamel-covered copper and has 40 ft) 22 Ga / 75 ft) 26 Ga / 200 ft) 30 Ga. Not sure about enamel vs. lacquer coating.
I guess it couldn't hurt to try thinner stuff. I am bi-wiring and could do 26 for the top and 22 gauge on the bottom.
Southwire (800) 444-3600 sells round, rectangular, and square magnet wire with nomex, kapton, or paper insulation. MWS (888) 697-9473 sells MULTIFILAR parallel bonded magnet wire said to offer consistent capacitance and impedance. Phelps Dodge Magnet Wire co sells coaings to apply to magnet wire. I couldn't find Michael Percy.

Going to http://www.sundial.net/~rogerr/wire.htm they recommend:
Wire Size 2 ohm 4 ohm 6 ohm
22 ga 3 ft max 6 ft max 9 ft max
20 ga 5 ft max 10 ft max 15 ft max
18 ga 8 ft max 15 ft max 23 ft max

This site also says when resistance gets too high it makes the amplifier look like a current source. "This means the speaker frequency response will tend to follow the rise and fall of the speaker's impedance curve. The impedance of most speakers is not constant with frequency". This could cause frequency response inconsistencies.

So since my speakers are 4 ohm and the run is 12 feet I felt safe with 18 ga. However since I'm bi-wiring I guess the 22 ga may work.
==>I don't want to burn the house down from overheating some micro-thin copper wire! <== Hence the thought on using teflon tubing.
If people have been using 26 ga with50 watts or more, I would wonder how long a run they had.
Cdc, I used the 22ga radio shack magnet wire on my 3 meter speaker runs. You can go without the tubing because of the protective enamel, but the enamel can get rubbed off and there is a small chance of shorting the wires together. For this reason I used tubing on mine. I also separated the runs by 2 1/2" all the way. With single-conductor runs, capacitance is really not an issue. With wires separated beyond the distance where the fields can interact, inductance is not an issue. I used 3/8" tubing around my wires in order to get mostly air-dielectric, except for the few small contact areas where the wire occasionally touches the tubing. In this case, even the dielectric is not an issue. The tubing provides a sound-wave barrier for the wire, so it will get less vibration, than if it was bare. Since the wire hardly touches the tubing, the tranferred vibration is minimal.
You will not heat up the speaker wires or damage anything. The tables you looked at are about 1% loss tables, and they really bear no relevence to this discussion, where the cable length is under 4 meters. The resistance difference at 4 meters is negligable. There is no risk of damage or fire with this type of wire and a 50 watt amp.
Twisting is usually a better performer because it locates the forwards and return wires in close proximity and creates some field cancellation. When the forward and return paths are in parallel or twisted, this lowers the inductance substantially over separated wires. Braiding is really only for convenience to hold multiple pairs together. Braiding actually degrades the performance. If you select a braid that mostly makes the pairs orthogonal to each other, this will help. I would recommend using enough twisted-pairs to equal 10-12 gauge.
(Thanks TWL)

CDC: TWL pretty much covers it. Also I like and will try his "big" tubing idea on the magnet wire that I have when I set up the second system.

Yes, the thin coating on magnet wire can become compromised (I always kept +/- separated with cotton ties/ribbon placed @ various places along the path), but again will try "big" tubing next time as it's more a sure thing (plus to see if it sounds better due to added damping).

TWL: Are you using clear inexpensive Lab tubing (the kind also used on ice makers in refrigerators), or is it Teflon tubing? Just curious as I have a bunch of the Lab stuff (used it for bare wire IC's once). Fry's has Teflon tubing now (and it is also not too expensive).

CDC: If you also end up trying the 18 gauge magnet wire then by all means experiment with Audioengr's recipe. When we (TWL & myself) recommend not twisting/braiding, this is in regard to the smaller gauge wire (not larger gauge solid core wire, such as 18 gauge).

Again, don't worry about the smaller gauges as long as the runs do not exceed 12' (8'-12' is the best range, IMO, for the smaller gauge wire based on trial and error).

As far as your BI-wirable speakers go, yes try 22/bottom and 26/top. Other options are running a single gauge through the bottom binding posts and then on up to the top posts all in one piece (you will have to strip the sections that make contact with the bottom posts, a well as the ends). If your speakers are out of warranty you could remove the internal leads from the top posts and attach them to the bottom posts (the speakers are no longer BI-wirable, but you have eliminated a set of binding posts in the signal path).

You could also try the "twisted" 18 gauge (two ply should be fine) on the bottom and then run a "short" single wire "jumper" (22-26 gauge) from the bottom posts to the top ones. I would not combine a single 12' run of the smaller wire on the top with a run of the twisted 18 gauge on the bottom as these cables will have very different voices and will sound odd. A short jumper (3"-6") however does not have this effect (guess such a short run does not have much character @ all:-) as I have tried this with braided Kimber Kable (on the bottom) and short 26 gauge jumpers running to the top (sounded good on a pair of Castle Isis speakers).

Don't mean to confuse you, but I am remembering all of the "cheap" things that I tried when I had the Castle's (current speakers are not BI-wirable). The best thing that I did (right off the bat) was to get rid of the stock plate jumpers and use a short run of speaker cable instead (big improvement in the mids and HF's).

I have to install some other gear in the living system next week (a preamp and a tuner) in order to test it and maybe I will get around to messing around with TWL's "big" tube idea. I will let you know if I do (I have the magnet wire and tubing on hand). The second system probably won't go up anytime in the near future (the room needs to be cleared out first).
Dekay, my big tubing is from Lowe's. I think it is polyethelene. I would have liked to have gotten Teflon, but I wanted to get the wires done, and didn't want to wait for mail order. Also, I figured that if the wire was not having alot of contact with the tubing that it wouldn't matter as much. I used 22ga, because my reading of the skin-effect literature said that 22ga is still under the skin-effect depth of copper. Single conductor runs reduce smear. To separate the runs, I used plastic Tee nipples about every 18" and connected them with a 2" piece of tube. This creates a kind of "ladder" appearance to the speaker cables, with the 2 runs staying about 2 1/2" apart. I guesstimated that 2 1/2" spacing would eliminate/reduce field interaction between the feed and return. If this is increasing the inductance, I sure can't hear it in any loss of high freq's. They look pretty exotic.I really don't know how much all this affected the sound, as I didn't A/B them without the tubing, and then with it. I just did it because I thought it would work out right. I am happy with the result. I will say this much: If these wires are holding any of my signal back, then I will sh!t bricks when I hear it with better cables. It is sounding REAL good right now.