Spark plug wire boot material

[bluestringer]

What is everyone using for spark plug wire boots. I'm using 30awg for the wires. I found some beads at HL, but they seem to large. 

[bluestringer]

I guess everyone buys ready made boots. 

[NOBLNG]

Get some old usb cable, phone charger wire or similar. Strip the wires out and use the insulation.
Google search: (site:modelcarsmag.com spark plug boots) will get a bunch of threads on the topic.

[Erik Smith]

I just use the insulation from a larger size wire. 

[Bainford]

I use a product called lacing cord (aka looming cord) marketed by RS Components. It is a 0.75 mm (.030") thin wall tube made of flexible, black PVC with a matte finish. It comes on a spool of 25 m (82') for about $10-12. The cord has some type of synthetic fibre running through it which must be pulled out of any piece you cut off the spool using pointed tweezers. The flexible and slow elastic nature of the stuff makes it easy to work with. The end of the tube can be bell-mouthed with a sewing needle, etc, and slipped over the ignition wire, distributor post, spark plug, etc, and eventually it relaxes and grips the item. I also use it for a number of plumbing jobs around the model, and many other uses. It is thinner wall and more flexible than next-size-up wire insulation, which was my old method before finding this stuff. RS PRO Lacing Cord Black PVC 0.75 mm x 25m | RS Components (rs-online.com)

Apologies for the lousy cell phone pics. Some wire boots in the first photo, the ones on the distributor are 90 degree boots. The second photo shows oil cooler lines down deep in the engine bay. In the third photo I even sliced a length of the stuff in half and made door window weather stripping.

Edited February 10, 2022 by Bainford

[R. Thorne]

Nothing lousy about those pics.  Great engine detailing.  Is the lacing .030” outside diameter?  If so, I assume, after removing the core, the inside diameter would be about .020”?  It appears this is on back order.  This is a UK company, I guess, so additional shipping adventures and delays are involved.  As my other post indicated, I am looking mainly for distributor cap boots (1/25 scale) and your suggestion looks good.  I don’t like the 1mm shrink tubing I am currently using because of the hassle of heating to shrink it.  Looks like the lacing is flexible enough to do the job.  I will try to find an equivalent US based product not on back order.  The wire loom separators are scratch built?  What material?  Your input is greatly appreciated.

[Mike C.]

I have a little of the black flexible tubing for the clutch and ignition cables from my 1/8 Chopper build that I was planning to use for this (provided it looks good size wize). My question is is there a source for this type of thing. This would also help James.

[Bainford]

On 2/10/2022 at 8:51 PM, R. Thorne said:

Nothing lousy about those pics.  Great engine detailing.  Is the lacing .030” outside diameter?  If so, I assume, after removing the core, the inside diameter would be about .020”?  It appears this is on back order.  This is a UK company, I guess, so additional shipping adventures and delays are involved.  As my other post indicated, I am looking mainly for distributor cap boots (1/25 scale) and your suggestion looks good.  I don’t like the 1mm shrink tubing I am currently using because of the hassle of heating to shrink it.  Looks like the lacing is flexible enough to do the job.  I will try to find an equivalent US based product not on back order.  The wire loom separators are scratch built?  What material?  Your input is greatly appreciated.

Thanks for the good words, Ron. Please check your inbox, you have a PM.

The .030" dimension was taken from the site info. I just measured a piece and it measured .035", which actually sounds a bit large, but not excessive. That would scale out to 7/8". The 90 degree boots are made by  cutting a notch halfway along a length of the cord, folding it 90 degrees at the bend, then touching it with a spot of CA and trim the ends to length. The photo below shows a 90 degree boot, though that one is not particularly tidy and was rejected.

The wire looms were made from .010" sheet plastic. I drilled a series of holes in the plastic until I had four that were sufficiently aligned and equally spaced, then trimmed away the material around them. I think the next time I make them I think I will try pop can aluminum instead of plastic. The plastic piece is pretty delicate when trimmed to size, and threading the wires through them was a bit nerve wracking.

[R. Thorne]

Thanks so much.  Sent you a reply.

[Zippi]

James, I'm also using 30 AWG wire.  I go to ACE hardware and buy some of their old beige phone line.  It's less than a buck a foot.  Peel the beige outer skin off and it has yellow, black, red, and green wires inside.  I strip off what I need from one of the wires and use that as the boots for my plug wires.  They are a little hard to fit onto the 30 AWG wire so I run a needle in the end to spread it open.  Hope this helps man.     

[Mike C.]

I like that idea. I have a few spools of that stuff somewhere.

[gary jackson]

yep telephone wire insulation   been using it for years