How I did a temporary repair to a coil cable

[otlew]

My Excalibur became erratic, it would not sound off on coins consistently as it should. I grasped the coil wire where it enters the control pod, moved it a bit and started working again. I suspected frayed broken outer strands in one or more of the 4 coil wires inside the jacket. The problem wire is not totally open or it would not work at all. So here is what I did as a temporary fix until I can tear it down and make a proper repair.

1. I unscrewed the strain relief boot and slid it back out of the way. I noticed a bump on the jacket of the coil wire, so I gently pressed it flat, after this the detector signals returned to normal.

2. I wrapped that area of the cable with a short piece of the "fixes anything silicone tape" (water pipes, garden hoses etc) perhaps you've seen the commercials. I bought it at Home Depot and the brand name is "Nashua Stretch and Seal" $7. When I wrapped the tape around the cable and pulled it tight it stiffened that area very well. I does not stick to the cable, it will only stick to its self, so you have to overlap it about 50%. Now the damaged area is fairly immobile.

3. I tried to slide the rubber strain relief boot backup the cable to the control pod, but it didn't want to pass over this very thin tape, a tight fit. I applied silicone grease to the cable and tape and with a twisting motion brought the rubber strain relief boot back up and screwed it on the control pod.

4. I applied some black flex guard cable shield for 1/4" cables (available at Frys/Radio Shack) , it comes split along its length and can be opened and slid over the cable then zip tied it at several places. I used about 8 inches in length and pushed the flex guard up onto the tapered rubber boot. I did a two inch piece on the battery cable and zip tied those two cables together to further stiffen the cables.

Now the the cable at the pod connection is not swinging around with each pass of the coil over the ground. The erratic behavior is now gone, hopefully until I can get the chance to fix it properly in the next few days. I intend to use this support system on all my detector coil cables.

 

[erikk]

Had U been using a hip,chest mount or on a straight shaft? BTW fix looks good

 

[otlew]

Yes I use a chest mount, but I am the second owner and have not put many hours on this unit. It came with the original shaft and as far as I know the person I bought it from did not have it on a straight shaft, but that might not be case. He may have kept his straight shaft and used with a new Excalibur.

 

[erikk]

Still one of the pitfalls of not using it mounted on a shaft. I have hundreds and hundreds of hours on my excals and the wires do not move while mounted on my straight shaft

 

[otlew]

I agree totally. The pods on a shaft should eliminate this issue.

Plugger has put a nice reusable tie down on his harness for the coil wire between the pod and the coil connector and if coil wire movement is restrained by this fixing point and at the coil shaft end also, I think it should greatly reduce the number of stress reversals which cause the fatigue failure in the copper coil wires. Especially if you add a bit of stiffening to the coil connection area at the control pod to minimize deflection. However, you are really only moving the fixed point further down the cable to the tie down where it will most likely occur again given enough time.

I would guess a large percentage of Excaliburs sent in for repair have been converted to hip or harness and that this mount contributed to a faulty coil wire, or have been improperly restrained at the shaft end near the coil. In other words many of the repairs probably are nothing more that failed coil wires at the connectors which could have been avoided.

Bottom line is if you want a harness or waist mount you should be prepared to repair/replace coils at some point in the future.

Still one of the pitfalls of not using it mounted on a shaft. I have hundreds and hundreds of hours on my excals and the wires do not move while mounted on my straight shaft

 

[erikk]

I agree totally. The pods on a shaft should eliminate this issue.

Plugger has put a nice reusable tie down on his harness for the coil wire between the pod and the coil connector and if coil wire movement is restrained by this fixing point and at the coil shaft end also, I think it should greatly reduce the number of stress reversals which cause the fatigue failure in the copper coil wires. Especially if you add a bit of stiffening to the coil connection area at the control pod to minimize deflection. However, you are really only moving the fixed point further down the cable to the tie down where it will most likely occur again given enough time.

I would guess a large percentage of Excaliburs sent in for repair have been converted to hip or harness and that this mount contributed to a faulty coil wire, or have been improperly restrained at the shaft end near the coil. In other words many of the repairs probably are nothing more that failed coil wires at the connectors which could have been avoided.

Bottom line is if you want a harness or waist mount you should be prepared to repair/replace coils at some point in the future.


I agree 100%

Still one of the pitfalls of not using it mounted on a shaft. I have hundreds and hundreds of hours on my excals and the wires do not move while mounted on my straight shaft

 

[OldBeechnut]

Hey..that is good stuff. Here is the same just a different company. I nicked my battery cable on the excal with the soildering iron, went to west marine.. guy said this will WP just about everything. Fixed the nick, and used it on my PP switch install....tuff as steel once you build up the layers.............then fix a leak on 3/4 copper tubing at the joint at GF's house...Good stuff for the road trips....

 

[synthnut]

Good Job Otlew !!......I keep a roll of this stuff in my kit when I go hunting .....I don't leave home without it !!......Great stuff ..... You just have to figure that any wire that it constantly moving back and forth is going to develop a weak spot sooner or later ....It's not if , but when ...... Jim

 

[erikk]

How about a demo video???

 

[otlew]

How about a demo video???

I will be tearing it down in 3 or 4 days to install the new coil. I will take some photos and post those in reverse order. I might do a video also, just depends on time available.

 

[Bling]

the end of the tube where 2 wires come out (battery and coil wire) is zip tie them together so there is double the strenght at the entry point.iv never had a broken wire there.

 

[otlew]

I put a zip tie near the end of the strain relief boots, not up by the connectors. The cable damage is about half way down the length of the sleeve.