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Spark plug wire for tubes with a top cap?

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Spark plug wire has well thought insulation layers very high dielectric strength, its very flexible, the boots can be repurposed to grommet into the chassis, and it looks cool and safe to the touch due to its thick insulation.

Construction-wise, there is straight copper wire, carbon core, spiral wound types and other methods of EMI reduction.


Do you think the straight copper spark plug wire would be a good choice for top capped tubes?
The wire I have just looks so dinky coming off a top cap. I'd replace the actual terminal to the tube with the correct size for the tube of course, or just fix a proper sized ceramic boot.


Constructions:

Getting Wired: Spark Plug Wires 101

A typical copper core set:

Amazon.com: JDMSPEED New 10.5mm Spark Plug Wire Set Replacement for HEI SBC BBC 350 383 454 Electronic: Automotive
 
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Do you think the straight copper spark plug wire would be a good choice for top capped tubes?

The short answer is yes. A concern is present. Low purity, "tough pitch", copper can contain copper oxide micro diodes that cause distortion. Obviously, "super duper" OFC cabling will not be used for spark ignition. Whether or not the copper used is pure enough is (IMO) an open question.
 
I use 18 AWG silicone slot car wire - it's nice and limp and comes in a wide range of colors. It doesn't have a specific voltage rating, but the insulation is rather thick, and being silicone, will stand up to heat and not get brittle with age. 18AWG is just the right size to fit in the hole of your usual plate cap.
 
Spark plug wire has well thought insulation layers very high dielectric strength, its very flexible, the boots can be repurposed to grommet into the chassis, and it looks cool and safe to the touch due to its thick insulation.

Construction-wise, there is straight copper wire, carbon core, spiral wound types and other methods of EMI reduction.


Do you think the straight copper spark plug wire would be a good choice for top capped tubes?
The wire I have just looks so dinky coming off a top cap. I'd replace the actual terminal to the tube with the correct size for the tube of course, or just fix a proper sized ceramic boot.


Constructions:

Getting Wired: Spark Plug Wires 101

A typical copper core set:

Amazon.com: JDMSPEED New 10.5mm Spark Plug Wire Set Replacement for HEI SBC BBC 350 383 454 Electronic: Automotive

Spark plug wire is about 1 kilohm per foot for current limiting of the spark (unless that changed) and usually uses carbon wire. I recommend heater cord Amazon.com: Power cord, 8', HPN 16/2, fits Heaters and Irons Must be Hardwired: Home Audio & Theater unless you are talking over 600V, in which case This: High Voltage Silver Plated Copper PTFE 20 AWG Wire 13 KV Gore F01B080 5 ft | eBay might do
 
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My bad. I should have read more closely. If it's truly low resistance wire, it should work. One of the reviews said it melted in one persons use so keep it away from the tubes. Also, it's gonna be pretty fat - it wouldn't fit into any of the plate caps I use.

You can get heater cord at any hardware store by the foot. I paid 20 cents/foot for mine. Just saying...
 
My bad. I should have read more closely. If it's truly low resistance wire, it should work. One of the reviews said it melted in one persons use so keep it away from the tubes. Also, it's gonna be pretty fat - it wouldn't fit into any of the plate caps I use.

You can get heater cord at any hardware store by the foot. I paid 20 cents/foot for mine. Just saying...

This was all a passing thought I had not liking the dinky wire I see coming off the 807 on my breadboard. I like the idea of having the harness to the cap be very flexible and with very thick insulation and look professional.

I wire up motorcycle accessories in my riding club using braided PET loom in many cool colors and snakeskin patterns. So a bit of that loom around the heater cord might be just the ticket to make it look cool and more shock proof!

Spark plug wire is just too specialized for EMI, if this subject ever comes up again here.
 
Belden test probe wire is perfect. It reminds me of spark plug wire but with somewhat smaller diameter insulation, so it should work with pretty much any plate cap. It is cheap and it is definitely not made of anything weird to enhance its performance as a spark plug wire that will cause problems in your application.

I mean, give spark plug wire a shot if you want to and let us know how it goes, but test probe wire will definitely give you what you want and isn't expensive.
 
I'd use 10KV silicone test lead wire - I may still have some white 40KV silicone CRT wire that would look good with the ceramic caps...

Good idea Tom! Amazon has 30KV white, pretty cheap too. It would match the ceramic caps and should be pretty safe for curious people that just have to touch everything. This one is about 4.5 mm .18 inch, it should make it into the cap.

XJS Electric Copper Core Flexible Silicone Wire Cable White 10M 32.8Ft (18AWG 30KV) - - Amazon.com
 
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Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.