Ignition/clip whip wire??

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I use #18AWG from RadioShack, dual conductor. But after using it for the first time yesterday, I don't recommend you getting stranded wire. It's not flexible at all, and tends to turn itself off of the ignitors. Maybe something thinner? Not sure.

How many motors do you plan on igniting?
Lamp Cord.

It's great! I have saved every lamp cord from every busted lamp for years, they are six to eight feet long, 18 AWG (that's American Wire Gauge for those across the pond...:D ) and very flexible. I find that I have to replace the aligator clips long before the cord wears out. Also I use the dual stacking banana plugs that you can get at Radio Shack, that way I can stack as many of these as I need for clusters, and not have to make clip whips.

My 2 cents.

Audio speaker wire works wonderfully as well. It comes in a variety of gauges but I use whatever I think isn't too thick nor too thin... I like using it because the wires are in pairs like lamp cord, however, one of the wires is visually marked positive (or negative). Less chance of getting your wires crossed :kill:
18 AWG is about the thickest you want to use. In that case, use lamp cord as it is the most flexible. The thicker you go, the more strands you want for flexibility.

What I usually recommend is that you match the wire in the rest of your system, gauge wise. If you are using 22 AWG from the controller to the pad, for example, it doesn't make any sense to use 18 AWG from the end of the wire to the microclips as the circuit is only as good as the thinnest wire allows.

For all of my *personal* launch controllers, I go with 22 AWG thoroughout as it is adequate for all of my needs, clusters included.

If I am doing a club launcher, I use 18 or 16 AWG throughout.

If you look at lamp cord, you will notice that one of the conductors is different from the other, usually ribbing on the insulation. Some lamp cord will also have a stripe on the conductor as well, it is just not quite as obvious as speaker wire.

I've brought, but not yet used, Silicone Extra Flexible Wire from Maplins (do a search for it on the site, I can't link directly to the product).

Its rated at being able to carry 32A, so it should do the job.

Originally posted by arthur dent
What sort of wire do you guys use for making clip whips??
I don't use wire, I buy Radio Shack jumpers with alligator clips on the ends. They usually come in packs of eight or so. Cut them in half, strip the ends, twist and solder. I've seen folks fold some flat copper braid and solder that over the tip as well. Don't forget to test continuity between the joint and each clip before you use it the first time.
Here is the Maplin wire:


32A @ 500V! Very beefy :D

Using Radio Shack jumper with build in alligator clips is a good idea. The clip whip I built for myself is too heavy to be very useful:

Radioshck sell these little jumper wires with presoldered alligator clips on each end, all different colors. All you dou is cut in half, twist, and solder, and your done. With these, I made a 4 engine clip whip in three minutes. Plus, when you are hooking the wires up, you just hook up the like colors.
Originally posted by Tarc3
Radioshck sell these little jumper wires with presoldered alligator clips on each end, all different colors. All you dou is cut in half, twist, and solder, and your done. With these, I made a 4 engine clip whip in three minutes. Plus, when you are hooking the wires up, you just hook up the like colors.

I have lost count of the number of times I have had the wires break in these Radio Shack clip leads. Then I would have to strip and resolder them. This was with the small variety and I haven't had the larger ones show the same failure mode. Yet.

I use these in a benign electronics workbench environment and I would expect their failure rate as igniter clips to be much higher.
I use 16 TFF or TFFN stranded copper fixture wire for all my cluster ignition systems. I don't actually use whips as such,rather the 18" to 24" *(shorter is better) 3 or 4 wire gangs are connected directly to the load side of my 40amp/contact DPDT power relays. with #6 or #8 stranded copper from the battery to the line side of the relay. the coil control launch circuit can be any size. I usualy use White 16gage lamp cord for contol wiring depending on how the conrtol circuit is wired.
I redid my clip whip today out of boredom. I used the Radio Shack jumper wires and retained the positive/negative coloring along with marking each pair of wires with colored wire ties:


This is much more managable than my previous clunky design :) The thinner wire and design of the clips makes it a lot easier to connect the clips to multiple igniters in my bench testing.

Now my only problem is the wire mess I make when I wrap everything up:


I should have used banana plugs to connect the long wire that runs out to the igniters. Maybe next time. Or I can rebuild this controller for a 4th time :p
I've taken a minimalist approach to clustering recently. I've used the clip whips but always had a concern with shorts. Further it takes a while to get everything ready at the pad.

maxxq gave me an idea about wire wrapping the igniter leads. That works well, but it takes some care. For the last couple of clusters, I successfully tried an arrangement shown in the attached photo. I simply attach wires (actually used old Christmas tree light wire) to each igniter lead with a "nickel sleeve." These sleeves are in the fishing gear area of many stores. You also can use standard "butt connectors," but the fishing sleeves cost something less than $2 for 100 sleeves. I crimp the sleeve to hold the igniter lead to the extended lead. If you're worried about shorts, wrap the crimped sleeve with a bit of masking tape. This is all done at home. Takes about 10 minutes for 3 igniters.

I insert the igniter with the modified leads into the motor and then twist the free ends together at the pad (parallel connection, of course)

To ensure that I have a good igniter, I check the resistance of (1) the igniter alone, (2) the igniter with the extended lead attached, and (3) the igniter with the extended leads after insertion into the motor. Resistance is 0.7-0.8 ohms. The extended lead adds no measureable resistance.

I use about 8-inch wires for the extensions. If you really want to save wire, reuse the wires but by clipping off the old sleeves and stripping off additional insulation. Eventually they'll get too short.

I'm sure this is not a new idea, but I'll not go back to clip whips.