Fuse holder repair

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jmurtap
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Fuse holder repair

Post by jmurtap »

I've been having trouble with my landing light fuse holder, I would have the push/twist it just right to make it work. Looking under the dash I've confirmed that this is a bad solder connection at the fuse holder. This looks like a repair that will be painful either way. My question is can we desolder the connection and install a crimped connection? Or are we best to just try and resolder? Any tips to doing this job from those that have done it would be greatly appreciated. Of course the best action would be a complete rewire with circuit breakers, but that's not going to happen anytime soon.
Thanks-
Jason
Jason P
53 170
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bagarre
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Re: Fuse holder repair

Post by bagarre »

You're best bet is to try to re-solder the joint by crawling up under the panel with a gun.
You'll want a good gun or pen that is going to melt the solder quickly (80 watt?) and put some flux on the joint.
It probably doesn't even need any more solder added. Just re-flow whats there.
Once you're curled up in place, have someone throw a heavy blanket (welding blanket?) over you in case it drips on your stomach. 8O

If you've never done this before, you're probably good for one shot before you decide to replace everything with fuses :)
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Bruce Fenstermacher
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Re: Fuse holder repair

Post by Bruce Fenstermacher »

Yes solder dripping on your stomach is not fun, I know. It's not fun when the joint gets so hot the solder melts and drips on your sock while flying either. That is how I new I had to do something to the joint to begin with.
  1. You need a good solder iron that has some mass and some heat because the terminal and wire have mass that needs to be heated. And you need to heat just the joint quickly without over heating the fuse holder.
  2. Remove the fuse while soldering so it does not draw heat from the solder joint.
  3. Clean the solder joint best you can prior to doing anything. Using a small wire brush which looks like a tooth brush, works best.
  4. Apply flux to help clean the joint.
  5. Be ready to apply more solder if necessary.
  6. If the fuse holder gets to hot you could ruin it. A heat sink on it might be required. At least don't over heat the fuse holder. If the joint doesn't solder quickly, remove the heat and allow the fuse holder cool.
If you don't know how to solder or don't have decent experience doing it, this is not the joint to learn on.

I know how to solder, have the experience and the tools. It is not a joint to be done without thought or the proper tools. I have done it and I'd do it again without question. I would not try to convert it to a crimp on connector. That is just not proper as the fuse holder is not that type but a solder type.
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blueldr
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Re: Fuse holder repair

Post by blueldr »

It shouldn't take much heat to solder the connection on a fuse holder so a soldering gun or pen should be capable of doing the job. It is not a good idea to use an acid core wire solder on an electrical connection. Rosin core is a better flux selection to preclude developing corrosion on the electrical connection. Very, very little additional solder should be needed if any at all. If you're not familiar with soldering, a little outside practice on some small pieces of copper wire is a good idea. A wire connection is , or should be, a very quick job. By that, I mean that it should be a job that heats very quickly since since the heat sink is such a snmall area. One of the principal requirements of soldering is that the parts to be soldered should be scrupulously cleaned, either mechanically or chemically, down to bare metal.
BL
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jmurtap
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Re: Fuse holder repair

Post by jmurtap »

I'm can solder fairly well with the right equipment, I currently have a crappy iron that rarely does any job very well. I guess I'll be shopping for a good one. Thanks Guys!
Jason P
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Bruce Fenstermacher
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Re: Fuse holder repair

Post by Bruce Fenstermacher »

The fuse holders we are talking about are in 25 amp circuits. The wires attached are significant gauge. This picture of a '48 right hand side with the 2 - 25 amp circuits in the middle and the right of the picture.
Fuses.JPG

A 15 watt pencil iron won't heat the wire and the tab of the fuse holder fast enough and thoroughly enough for a proper solder joint.

Note the corrosion in the fuse holder joint in the center holder in this picture. This all needs to be cleaned.
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jmurtap
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Re: Fuse holder repair

Post by jmurtap »

Look at all the room you've got.. Lol mine is a lot more cramped, we'll wish me luck.. Ha maybe I'll hire it out..
Jason P
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Re: Fuse holder repair

Post by jmurtap »

No easy task to even take a picture and hold a light..
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170C
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Re: Fuse holder repair

Post by 170C »

Time to make a buying trip to that aviation hardware store (Harbor Freight) for a new soldering gun :D
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jmurtap
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Re: Fuse holder repair

Post by jmurtap »

Found me a nice 60w weller, should work nicely.
Jason P
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jmurtap
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Re: Fuse holder repair

Post by jmurtap »

Success!! That went better that I had expected. Turns out the two wires, was a single wire through the eye. Sure made the job easy. I was really afraid that I would unsolder both wires and have no way to hold them while I resoldered. New iron worked great!! Thanks everyone!!
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Bruce Fenstermacher
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Re: Fuse holder repair

Post by Bruce Fenstermacher »

Great. And I learned I should through away my soldering station sponge, that is never wet anyway, for a fancy $9 gold tube with a $2 brass/copper pot scrubber in it. Of course being frugal I just stole a copper pot scrubber from my kitchen and jammed it in a ring cut from a Jiffy peanut butter jar. Works great.
IMG_1563.jpg
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lowNslow
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Re: Fuse holder repair

Post by lowNslow »

Bruce Fenstermacher wrote:Of course being frugal I just stole a copper pot scrubber from my kitchen and jammed it in a ring cut from a Jiffy peanut butter jar. Works great.
Love it! Great tip.
Karl
'53 170B N3158B SN:25400
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